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Sample records for 14c 32p 35s

  1. Infection of neuroblastoma cells with Semliki Forest virus. Incorporation of 35S or 32P

    International Nuclear Information System (INIS)

    Phosphate-free medium is used for the incorporation of 32P and methionine-free medium for 35S-methionine labelling. After virus replication, the culture shows a clear CPE all of the cells appearing round and dead. Materials used are presented and experimental procedure is described

  2. Searches for heavy neutrinos from 35S, 14C, and 63Ni beta decay

    International Nuclear Information System (INIS)

    We have searched for the effect of a neutrino of mass 17 keV/c2 in the beta decay of 35S with an apparatus incorporating a high resolution solid state detector and a super conducting solenoid. The experimental mixing probability of the 17keV neutrino is consistent with zero. The experimental sensitivity is verified by measurements with a mixed source of 35S and 14C, which artificially produces a distortion in the beta spectrum similar to that expected from the massive neutrino. Recently, we have performed similar searches in the beta decay of 14C and 63Ni. Results of these new measurements will be presented

  3. Metabolism and distribution of 14C- and 35S-labeled carbon disulfide in immature rats of different ages

    International Nuclear Information System (INIS)

    The metabolism and distribution of 14C- and 35S-CS2 was examined in 1-, 5-, 10-, 20-, 30-, and 40-day-old rats. During a 3-hr period following an ip dose of 14C-CS2, 58-83% of the dose was expired as CS2 and 4-9% was metabolized to expired CO2 depending on age. Thirty- and forty-day-old rats metabolized significantly more CS2 to CO2 and expired significantly less CS2 than 1- through 20-day-old rats. At the end of the measured expiration period, only biotransformation products of CS2, which were in part covalently bound, remained in tissues from rats of all ages. Tissue levels of 35S-CS2-derived radioactivity exceeded levels of 14C-CS2-derived radioactivity indicating that sulfur metabolites free from the carbon atom of CS2 were formed in rats as young as 1 day of age. The 35S-CS2-derived radioactivity per g of tissue and thus 35S covalently bound to tissue protein was significantly higher in 1- through 20-day-old rats than in 30- and 40-day-old rats. Twenty-four hr after dosing, up to 13 times more 35S-labeled metabolites were covalently bound in organs from 1-day-old rats than in similar organs from 40-day-old rats. The results showed that elimination of the biotransformation products of CS2, in particular the covalently binding sulfur metabolites, was prolonged in newborn rats in comparison to 40-day-old rats

  4. The mineral nutrition of millet (Pennisetum-typhoides): Migration of 32P and 35S - Similarities with the migration of photosynthetic assimilates

    International Nuclear Information System (INIS)

    The paper describes a study of the transport of 32P and 35S injected into leaves or of 14CO2 absorbed thereby. It is shown that the radioisotopes mostly travel towards the upper parts of the plant and towards the seeds when they originate from upper leaves after male flowering. The later fillers, however, do not play any role as a reserve in the mineral or carbon nutrition of adult fillers. No appreciable absorption of 35S or 32P by the roots is observed after male flowering. (author)

  5. Effects of source distribution, dose, and linear energy transfer capacity on inactivation and mutation of mycobacteria after 2H, 35S, and 32P incorporation

    International Nuclear Information System (INIS)

    Using a selected model, the paper makes a contribution to the question whether the energy dose as a macroscopically-physically defined quantity can be usefully applied in cell ranges with linear dimensions of the order of 1 μm, i.e. whether there is still a correlation between the energy dose and quantitatively measurable biological radiation effects. The problem is investigated with the aid of the intracellular β decay of the 3H, 35S, and 32P nuclei on mycobacteria (BCG) in liquid media. Quantitative findings of radiobiological experiments are linked with model dose calculations to form dose-effect curves. The experimental principle consists in adding radioactively labelled compounds to the nutrient solution of bacteria at normal growth temperatures, thus obtaining an intracellular β source region caused by their uptake. The uptake conditions for the three radionuclides are varied by using different chemical bonds (2H) or carrier concentrations (3H, 35S). As biological reactions, inactivation in the form of growth inhibition and mutagenic induction of resistance to isonicotinic acid hydrazide are recorded. (orig./MG)

  6. Effect of aldicarb on growth and radio-carbon (14C) and radio-phosphorus (32P) assimilation by Rhizobium japonicum

    International Nuclear Information System (INIS)

    In vitro studies on the effect of aldicarb (2-methyl-2-(methyl thio) propionaldehde-o-methyl carbamoyl oxime), a soil applied systemic insecticide, on Rhizobium japonicum revealed that the chemical (at 1,2 and 5 ppm levels) stimulated the growth of the organism initially upto 48 hr which declined thereafter upto 72 hr. The incorporation of 14C-glucose by the cells considerably reduced due to the insecticide treatment. The production of extracellular, water-soluble slime (polysacchardes) was also reduced considerably with increased concentrations of the chemical. However, the incorporation of 14C-radio-activity in the extracellular slime generally enhanced due to the treatment, upto 6 hr after injection of the radioactivity, which declined significantly later at 15 hr, indicating a qualitative difference in the extracellular polysaccharides produced by the insecticide treated cells. The insecticide treatment drastically reduced the incorporation of 32P-disodium hydrogen phosphate into Rhizobium cells, but enhanced the specific activity of the extracellular polysacchrides. (author)

  7. Real-time imaging of 35S-sulfate uptake in a rape seed plant

    International Nuclear Information System (INIS)

    We present real-time images of 35S-sulfate uptake in a rapeseed plant visualized by the system we developed. In the leaves of rapeseed plants, 35S accumulated in higher amounts and more rapidly in the more developed leaves. This real-time imaging system can be used to visualize the movement of both 35S and 32P in the same plant. In the pods of rapeseed, images of 35S show that 35S accumulated mostly in the terminal parts; on the other hand 32P, when applied as 32P-phosphoric acid, accumulated in the middle part of the pods. (orig.)

  8. Main: CTRMCAMV35S [PLACE

    Lifescience Database Archive (English)

    Full Text Available CTRMCAMV35S S000460 27-March-2004 (last modified) kehi CT-rich motif (inverted GAGA...) found in a 60-nucleotide region (S1) downstream of the transcription start site of the CaMV 35S RNA; Can e...nhance gene expression; Inverted GAGA; See also S000405, S000427 (GAGA); (TC)4T; CaMV 35S; enhancer; Cauliflower mosaic virus (CaMV) TCTCTCTCT ...

  9. 2012 Rose Site 32P

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — Underwater Site 32P was established off Rose Atoll, American Samoa by Dr. James Maragos, U.S. Fish & Wildlife Service, on August 2, 2004. With a start point...

  10. 2004 Rose Site 32P

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — Underwater Site 32P was established off Rose Atoll, American Samoa by Dr. James Maragos, U.S. Fish & Wildlife Service, on August 2, 2004. With a start point...

  11. Real-time imaging of {sup 35}S-sulfate uptake in a rape seed plant

    Energy Technology Data Exchange (ETDEWEB)

    Nakanishi, T.M.; Yamawaki, M.; Ishibashi, H.; Tanoi, K. [Tokyo Univ. (Japan). Lab. of Radioisotope Plant Physiology

    2011-07-01

    We present real-time images of {sup 35}S-sulfate uptake in a rapeseed plant visualized by the system we developed. In the leaves of rapeseed plants, {sup 35}S accumulated in higher amounts and more rapidly in the more developed leaves. This real-time imaging system can be used to visualize the movement of both {sup 35}S and {sup 32}P in the same plant. In the pods of rapeseed, images of {sup 35}S show that {sup 35}S accumulated mostly in the terminal parts; on the other hand {sup 32}P, when applied as {sup 32}P-phosphoric acid, accumulated in the middle part of the pods. (orig.)

  12. Neuropeptides labelled with [sup 35]S

    Energy Technology Data Exchange (ETDEWEB)

    Kaspersen, F.M.; Nispen, J.W. van; Sperling, E.M.G.; Vader, J.F. (Organon Int BV, Oss (Netherlands))

    1993-01-01

    Methionine and cysteine containing peptides can be labelled with [sup 35]S by coupling of [sup 35]S-cysteine or [sup 35]S-methionine with a large excess of suitability protected peptide precursors. This is illustrated for [pGlu[sup 4], Cyt[sup 6

  13. The use of radioisotopes 32P and 35S in studies on behavior of pesticides in the soil

    International Nuclear Information System (INIS)

    Radioisotopes were used to determine the possibility and extent of contamination of underground waters by pesticides used in agriculture. The sorption and dynamics of the migration of two organo-phosphorous pesticides, fenitrothion and malathion, were studied. These two products are currently being proposed as agricultural pesticides. They would replace other substances of the chrlorinated hydrocarbon group, including DDT, which are more dangerous to health, but are themselves source of potential contamination of underground waters. Studies were carried out on different types of soil: sandy and clay. Isotherms were determined for the sorption of the pesticides examined, together with their distribution coefficients, Kd. The effects of pH values, exchangeable ions, organic substances (organic C and N) and the mechanical composition of the sorption of fenitrothion and malathion were studied

  14. Preparation of 35S labelled thiosemicarbazone

    International Nuclear Information System (INIS)

    A 35S labelled thiosemicarbazone is prepared, on a millimole scale by reacting labelled thiocyanate with hydrazine sulfate in ethanolic medium. The hydrazine thiocyanate so formed is then condensed with aldehyde to form the thiosemicarbazone

  15. Biosynthetic preparation of 35-S labelled methionine

    International Nuclear Information System (INIS)

    High specific activity methionine with sulfur-35 was prepared in our laboratory by growing Baker's yeast cells, in a medium containing 35S-sulfate. L-S35 methionine was prepared from the acid hydrolyzate of the proteins by chromatography on whatman paper. The specific activity was determined using o-phtaladehyde as a fluorophore to form a fluorescent complex. The specific activity was found to be usually greater than 800 Ci/mmol. (Author)

  16. The early history of (32) P as a radioactive tracer in biochemical research: A personal memoir.

    Science.gov (United States)

    Gest, Howard

    2005-05-01

    The concept of using radioactive isotopes as "tracers" of chemical conversions was conceived and developed by inorganic chemist Georg de Hevesy (Nobel Laureate in Chemistry 1943). In 1935, he began to apply the technique to various biological processes using (32) P, and his experiments revealed the dynamic character of physiology and metabolism. Following de Hevesy's lead, Samuel Ruben (University of California, Berkeley) exploited (32) P in 1937-38 for investigation of phospholipid metabolism. Between 1937 and 1940, Ruben and colleague Martin Kamen spearheaded tracer studies in various biological systems using (32) P, short-lived (11) C, and other radioactive isotopes. During this period, Kamen was responsible for cyclotron-produced radioactive tracers and was able to sustain de Hevesy's research by supplying him with (32) P. In 1940, Ruben and Kamen discovered long-lived (14) C, which later proved to be a very powerful tool for analysis of complex biochemical processes, such as the path of carbon in photosynthesis. Between 1946 and 1950, (32) P was used in studies of bacteriophage replication and photosynthetic metabolism. This memoir surveys the history of these early investigations. PMID:21638569

  17. Thermophilic Anaerobic Biodegradation of [14C]Lignin, [14C]Cellulose, and [14C]Lignocellulose Preparations

    OpenAIRE

    Benner, Ronald; Hodson, Robert E.

    1985-01-01

    Thermophilic (55°C) anaerobic enrichment cultures were incubated with [14C-lignin]lignocellulose, [14C-polysaccharide]lignocellulose, and kraft [14C]lignin prepared from slash pine, Pinus elliottii, and 14C-labeled preparations of synthetic lignin and purified cellulose. Significant but low percentages (2 to 4%) of synthetic and natural pine lignin were recovered as labeled methane and carbon dioxide during 60-day incubations, whereas much greater percentages (13 to 23%) of kraft lignin were ...

  18. Soil 35S Transformation and Availability to Plants

    Institute of Scientific and Technical Information of China (English)

    ZHOUWEI; PANJIARONG

    1999-01-01

    Sulfur transformation in 3 soils maintained in a closed incubation system and its availability to plants were investigated using carrier-free 35S-SO42- and 35S-labeled ryegrass straw.For carrier-free Na235SO4 treatment,78%,70%and 64% of 35S applied were found in Ca(H2PO4)2-extractale S fraction,4%,5% and 7% in slowly soluble inorganic S,11%,15%and 18%in C-O-S,5%,7%,and 6% in C-bonded S,and 5%,7% and 6% in unidentified organic S120 days after incubation in black soil,cinnamon soil and chestnut soil,respectively.Most of 35S uptake by plants came from extractable 35SO42-,and little from C-O-35S and C-bonded 35S,In the treatment with 35S-labeled straw,51%,46%and 36% of 35S incorporated were found in Ca(H2PO4)2-extractable S fraction,7%,6% and 7% in slowly soluble inorganic S,13%,15%and 18% in C-O-S,8%,8%and 6% in C-bonded S,and 18%,25%and 35% in unidentified organic S at the end of incubation in above-mentoned three soils,respectively.Higher availability of C-O-35S,C-bonded 35S and unidentified organic 35S from 35S-labeled straw was observed in 35S-labeled straw treatment compared to carrier-free Na235SO4 treatment.

  19. Incorporation of 14C from [14C]phenylalanine into condensed tannin of sorghum grain

    International Nuclear Information System (INIS)

    A procedure is described for obtaining condensed tannin from sorghum [Sorghum bicolor (L.) Moench] seeds metabolically labeled from [14C]phenylalanine. The [14C]tannin should be useful in determining the metabolic fate of dietary condensed tannin

  20. Dry extraction of 14C02 and 14C0 from Antarctic ice

    NARCIS (Netherlands)

    Roijen, J.J. van; Bintanja, R.; Borg, R. van den; Broeke, M.R. van den; Jong, A.F.M. de; Oerlemans, J.

    1994-01-01

    A dry extraction method was used to obtain trapped CO, of 2-5 kg ice samples from a blue ice zone in East Antarctica. In situ produced 14C was also extracted in 14C0, and 14C0 concentrations at a ratio of 3.4 f 0.9. Correction of trapped 14C0, from in situ resulted in ice dates in the range 5-15 ka.

  1. Separation of 35S-sulfate on neutral aluminium oxide

    International Nuclear Information System (INIS)

    The results of 35S-sulfate chromatography on neutral aluminium oxide (γ-Al2O3) are presented. Possibility of quantitative adsorption of 35S-sulfate on Al2O3 from acidic or neutral potassium chloride solutions of high concentration is shown. Dynamic adsorption capacity of neutral aluminium oxide with respect to sulfate from weakly acidic potassium chloride solution equals near 10 μmol/ml of adsorbent. Optimal parameters for chromatographic isolation of 35S-sulfate without carrier from irradiated KCl target are determined. (author)

  2. Applications of 10Be, 14C, and 32Si to geological questions

    International Nuclear Information System (INIS)

    Radiometric dating is regarded as fundamental to any modern timescale calibration. In terms of available isotopic dating and tracing tools in environmental sciences, the cosmogenic isotopes stand out because of their application in the range from the very recent up to the middle Miocene. At IGNS, three long-lived cosmogenic isotopes can be measured. 14C (half life=5730 years) and 10Be (half-life = 1.5 Ma) are measured by Accelerator Mass Spectrometry (AMS) of 10Be/9Be and 14C/13C ratios, while 32Si (half-life > 140 years) is measured by radioactive decay counting of its daughter-product 32P. The main advantage of AMS over decay counting is the relatively small amount of sample material needed. AMS has made it feasible to measure ultra-low concentrations of long-lived isotopes such as 10Be. (author)

  3. Synthesis of dexamethasone-4-14C

    International Nuclear Information System (INIS)

    The bismethylenedioxy (BMD) derivative of dexamethasone 2 was silylated with trimethylchlorosilane and imidazole in dimethylformamide to give the 11β-trimethylsilyloxy BMD derivative 3. The Δ1-double bond in 3 was hydrogenated over 5% palladium on carbon to give the Δ4-3-oxo steroid 4. Oxidation of 4 with potassium permanganate-sodium metaperiodate gave the seco-acid 5 which on subsequent treatment with acetic anhydride; sodium acetate and triethylamine gave the enol-lactone 6. The enol-lactone 6 was reacted with 14C-methylmagnesium iodide to give an adduct 7a which on heating at reflux with lithium 2,6-di-t-butylphenoxide in dioxane gave the Δ4-3-oxo derivative 8. Compound 8 was heated at reflux with m-iodylbenzoic acid and diphenyl diselenide in toluene to give the Δsup(1,4)-3-oxo steroid 9. The protecting BMD and silyl groups were removed in a single step by reaction with aqueous trifluoroacetic acid containing 2N hydrochloric acid at room temperature to give dexamethasone-4-14C 10. (author)

  4. Measuring 35S of Aerosol Sulfate: Techniques and First Results

    Science.gov (United States)

    Brothers, L. A.; Dominguez, G.; Bluen, B.; Corbin, A.; Abramian, A.; Thiemens, M. H.

    2007-12-01

    On a global and regional level, the cycling of sulfur in the environment has consequences for air quality, human health, and may contribute to global climate change. Due to its multiple oxidation states, the sulfur cycle is very complex and poorly understood. Stable isotopes are currently used to understand reaction pathways as well as sources and sinks of sulfurous compounds in the environment. Sulfur also has one short lived (τ1/2 ~87 d) radioactive isotope (35S) which is continuously made in the atmosphere by the cosmic ray spallation of argon, is then quickly oxidized to 35SO2 and enters the atmospheric sulfur cycle. The short-lived radioactive nature of this isotope of sulfur provides us with potentially powerful tracer for understanding the time scales at which sulfur is oxidized, deposited, and transported in the atmosphere and the deposition of atmospheric sulfate into rivers and water catchments. However, despite its potential, the use of 35S as a tracer of aerosol chemistry has not been fully exploited, Here we present details of instrumental set up for measuring 35S in aerosol sulfate and some preliminary results of measurements of 35S abundances in aerosols from Riverside (inland) and La Jolla (coastal) CA and discuss the sensitivity and limitations of the measurements in providing insights into day/night aerosol chemistry (Riverside) as well as the uptake of SO2 pollution in coastal environments by sea-salt aerosols. Also, we present preliminary results from measurement of sulfate in river water in Ecuador before and after precipitation events.

  5. Decomposition and excretion of 32P-naled in milk

    International Nuclear Information System (INIS)

    The 32P-labelled organophosphorus insecticide naled is decomposed in milk in vitro at 5 0C with a half-life of 35 h with dichlorvos as a metabolite, that is also formed at short time heating and UV-irradiation. The recovery in milk powder is 25% (naled + dichlorvos) of the initial concentration. Following spray application of 0.05 mg naled/kg body mass to 2 lactating cows, 5 - 8 ppb of naled and 7 - 9 ppb of dichlorvos were found in the milk 5 h after application, not exceeding the tolerance level of 0.02 mg/kg according to regulations in the GDR. (author)

  6. Pharmacokinetics and tissue distribution of 14C-5-aminosalicylic acid (14C-5-ASA) in rats

    International Nuclear Information System (INIS)

    5-Aminosalicylic acid (5-ASA) is effective in the treatment of ulcerative colitis and Crohn's disease. As part of a preclinical metabolism profile with 5-ASA, we evaluated the tissue level and distribution of 14C-5-ASA in rats. Biodistribution of 14C-radioactivity was determined in the major organs of rats after a single oral dose (34 mg/kg; 15 uci/rat). Data from tissue area under the curve (AUC 0-72) indicated that the highest amounts of radioactivity were retained in cecum (481.1 hr.ug.equ/gm), colon-rectum (178.5 hr.ug.equ/gm), ileum (166.7 hr.ug.equ/gm), jejunum (65.5 hr.ug.equ/gm), followed by kidneys (58.0 hr.ug.equ/gm) and liver (14.8 hr.ug.equ/gm). The radioactivity retained in tissues at 72 hours postdose was wither nondetectable or less than 0.1 ppm. The radioactivity concentration in blood was highest at 0.5 hr (tmax) postdose and the terminal half-life (t1/2) of 14C-radioactivity (5-ASA + metabolite) was 2.7 hours. 14C-5-ASA is absorbed and distributed in the body. The greatest amount of 14C-radioactivity was found in the stomach and GI tract. 14C-5-ASA was eliminated completely (44.9% in the urine, 51.7% in the feces) 72 hours after administration without significant tissue retention

  7. Forensic applications of 14C at CIRCE

    Science.gov (United States)

    Marzaioli, F.; Fiumano, V.; Capano, M.; Passariello, I.; Cesare, N. De.; Terrasi, F.

    2011-12-01

    The decreasing trend of the radiocarbon pulse produced during the atmospheric tests of nuclear weapons (bomb-carbon) coupled with high sensitivity accelerator mass spectrometry (AMS) measurements, drastically increased the precision of radiocarbon age determinations since the second part of the sixties, allowing the application of radiocarbon AMS to a wide range of studies previously not directly involving conventional radiocarbon dating (i.e. food authenticity, forensic, biochemistry). In the framework of authenticity evaluation of artworks, high precision radiocarbon ( 14C) AMS measurements (Δ R/ R < 0.3%) reduce the conventional uncertainty of the dating to few decades, allowing precise age estimation of materials containing carbon (C). The Centre for Isotopic Research on Cultural and Environmental heritage (CIRCE) during its activity on AMS 14C dating achieved high precision measurements opening the opportunity to these kinds of applications. This paper presents the main results obtained from radiocarbon measurements on a set of bone samples analyzed for the determination of the post-mortem interval in the framework of an unsolved case investigated by the Rome prosecutor office. The chronological characterization of the wooden support of the "Acerenza portrait" is also presented with the aim to evaluate its age and to further investigate the possibility to attribute this artwork to Leonardo da Vinci. Bomb- 14C dating on the lipid and collagen fractions of bones allows the evaluation of the year of the death of the individuals by means of ad hoc calibration data sheet with the typical few years precision and difference between collagen apparent age and the year of death appeared in agreement with the age of one individual estimated by dating of tooth collagen. Conventional radiocarbon dating on both wood and wood extracted cellulose leads to an estimation of the portrait wood board age (2σ) of 1459-1524 AD (57% relative probability), 1571-1631 AD interval (42

  8. Synthesis of. beta. -sitosterol-/sup 14/C

    Energy Technology Data Exchange (ETDEWEB)

    Askinazi, B.Z.; Kivokurtseva, L.N.; Bobrova, N.S.; Kozarinskaya, N.Ya.

    1986-08-01

    The method of synthesis of ..beta..-sitosterol-4-/sup 14/C starting with the enolactone 4-oxa-5-sitosten-3-one is discussed. Methyl-/sup 14/C magnesium iodide is utilized for the introduction of the label. The authors selected this method for the isolation of ..beta..-sitosterol-/sup 14/C, introducing a series of changes into the original method. The authors discuss obtaining sitostenone, the ketoacid of sitostenone, the enol-lactone of the ketoacid of sitostenone, sitostenone-4-/sup 14/C (by different methods), the enol-acetate of sitostenone-/sup 14/C, and ..beta.. sitosterol-4-/sup 14/C.

  9. Production of some inorganic forms of 35S at the Boris Kidric Institute

    International Nuclear Information System (INIS)

    Several inorganic forms of 35S are used as starting material for some chemical syntheses of labelled organic compounds. The choice depends on the desired characteristics of the labelled compound. Preparation of elementary sulphur 35S, sodium sulphide-35S, ferrous sulphide-35S, barium sulphate-35S, barium sulphide-35S, is described. The characteristics of the products are given along with the determination methods. The products are obtained with high specific activities: elementary sulphur-35S, 1 - 5 Ci/gS; sodium sulphide-35S 1 - 5 Ci/gS; ferrous sulphide-35S, 1 - 5 Ci/gS; barium sulphate-35S, 5 - 15 Ci/gS; barium sulphide-35S, 1 - 5 Ci/gS. (author)

  10. A novel synthesis of ethanolamine-2-14C

    International Nuclear Information System (INIS)

    Ethanolamine-2-14C was prepared by the reduction of benzyloxycarbonyl-glycine-1-14C methyl ester. The reduction was carried out with calcium borohydride and the protecting group was removed by hydrogenolysis. (author)

  11. Rarotonga Radiocarbon (delta 14C) for 1950 to 1997

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Rarotonga coral radiocarbon (14C) timeseries. Coral radiocarbon (Delta-14C) on untreated, low-speed drilled samples. Precision is +/- 4 per mil as documented by an...

  12. Quantifying 32P-labeled and unlabeled nucleic acids

    International Nuclear Information System (INIS)

    Recombinant DNA technology depends on detection methods for nucleic acids compatible with amounts ranging from picograms to grams and from tenths of a microliter to liters. In practical terms there are three basic techniques: (1) absorbance methods suitable for a minimum concentration of micrograms per milliliter, (2) fluorescence methods capable of detecting nanograms of DNA and micrograms of RNA, and (3) methods based on the detection of 32P. Because of the overwhelming importance in molecular biology of the third group, this chapter will stress exquisitely sensitive methods for measuring radioactivity in very small volumes. An illustration in which an enzyme-catalyzed reaction performed in 20 μl is monitored by consuming less than 2% of the total volume will be presented

  13. Essential thrombocythemia treated with oral sup(32)P

    International Nuclear Information System (INIS)

    A 65-year old man was admitted due to protracted gum bleeding after dental surgery. The peripheral blood smear showed thrombocytosis(1,160,000/mm3) with bizarre, giant platelets. The paltelet adhesiveness revealed 28% (normal control 31-85%) by Salzman method and the platelet aggregation revealed moderately delayed response to collagen, but normal responsiveness to A.D,P, and no responsiveness to epinephrine, the spleen scan(sup(99m)Tc-NaTcO4) showed the finding of splenic infraction. The gum bleeding ceased after transfusion of 8 units of platelet rich plasma, and he was treated with oral sup(32)P(2.5mCi/m2) under the diagnosis of essential thrombocythemia. The platelet count returned toward normal 2 months after treatment, and he was in good healthy condition. (Author)

  14. [Disintegration and elimination of 32P-naled in milk].

    Science.gov (United States)

    Dedek, W; Scheybal, A; Gabrio, T; Kirst, E

    1981-01-01

    The organophosphorus insecticide naled (O,O-dimethyl-O,O-(1,2-dibromo-2,2-dichloroethyl)-phosphate, labeled by 32P] is degraded in milk in vitro at 5 degrees C with a half-life of 35 h with dichlorvos as a metabolite, that is also formed at short time heating and UV-irradiation. The recovery in milk powder is 25% (naled + dichlorvos) of the initial concentration. Following spray application of 0,05 mg naled/kg body mass to 2 lactating cows, 5-8 ppb of naled and 7-9 ppb of dichlorvos were found in the milk 5 h p.a., not exceeding the given tolerance level of 0,02 mg/kg in the German Democratic Republic. PMID:7290169

  15. 14C-丁草胺、14C-毒死蜱和14C-DDT在日本林蛙中的生物学行为%BEHAVIORS OF 14C-BUTACHLOR,14C-CHLORPYRIFOS AND 14C-DDT IN Rana japonica japonica Guenther

    Institute of Scientific and Technical Information of China (English)

    张奕强; 张海清; 钟创光; 赵小奎; 陈舜华

    2002-01-01

    用同位素示踪技术研究了14C-丁草胺、14C-毒死蜱和14C-DDT在日本林蛙(Rana japonica japonica Guenther)中的生物学行为.结果发现,14C-丁草胺、14C-毒死蜱和14C-DDT在24h后分布到青蛙的各个器官组织,并分别以胆囊、小肠、小肠为它们的特异性浓集器官.与胆囊或小肠的14C放射性活度比较,其它器官组织中的要小得多.14C-DDT在日本林蛙中较难降解,24h后DDT母体在肝和脂肪组织中占DDT代谢物的54.6%和88.4%.青蛙中的14C-丁草胺、14C-毒死蜱和14C-DDT可被丙酮提取,但三者之间以及在青蛙的器官之间有差异.%The research on the behaviors of 14C-butachlor, 14C-chlorpyrifos and 14C-DDT in the frog Rana japonica japonica Guenther was carried out. After administrated per os to the frogs in doses of 380,347,363 Bq/g, 14C-butachlor, 14C-chlorpyrifos and 14C-DDT, were distributed respectively to various organs within 24 h with specific accumulating organs as gallbladder, intestine and intestine, relevantly to the pesticides described. Compared to that in gallbladder and intestine, the radioactivity of many organs was extremely low, and this might due to the characters of the pesticides. Analysis of the metabolites of 14C-DDT in frog at 24th hr demonstrated that DDT was difficult to be degraded. Most 14C-butachlor, 14C-chlorpyrifos 14C-DDT in liver and fat or ovary of frog was extractable with acetone. However, there were some differences between the pesticides, and the organs as well. And 14C-butachlor, 14C-chlorpyrifos or 14C-DDT were better bound in liver than in fat.

  16. {sup 14}C AMS dating Yongcheon cave

    Energy Technology Data Exchange (ETDEWEB)

    Lee, J.H., E-mail: jefflee@snu.ac.kr [AMS Lab., NCIRF, Seoul National University, Seoul 151-742 (Korea, Republic of); Choe, K. [AMS Lab., NCIRF, Seoul National University, Seoul 151-742 (Korea, Republic of); Kim, J.C. [Dept. of Physics and Astronomy, Seoul National University, Seoul 151-742 (Korea, Republic of); Choi, S.H.; Kang, J.; Song, S.; Song, Y.M. [AMS Lab., NCIRF, Seoul National University, Seoul 151-742 (Korea, Republic of); Jang, J.G. [Jeju National Museum, Jeju 690-782 (Korea, Republic of)

    2013-01-15

    The biggest island in South Korea is Jeju Island, which lies 80 km south of the mainland and has one shield volcano, Mt. Halla. The volcanic island and its lava tubes were added to the world heritage list by UNESCO in 2007. Among the many lava tubes on the island, a unique cave had been accidentally found in 2005 while some workers were replacing a telephone pole. Until the discovery, it had been completely isolated from the outside by naturally-built sand blocks. Yongcheon cave is a lime-decorated lava tube showing both the properties of a volcanic lava tube and a limestone cave. This cave, about 3 km in length, is acknowledged to be the best of this type in the world and includes a large clean-water lake, lava falls, and richly developed speleothems inside it. Even though there is archaeological evidence from well preserved pottery that ancient people entered this place, the preservation of artifacts was ensured by a geological change that made later entrance difficult. We have collected charcoal samples scattered around the cave and dated them using AMS. Ages were in the range of ca. 1570-1260 BP (A.D. 340-880) and this corresponds to the Ancient Three Kingdoms and the Unified Silla era in Korean history. The {sup 14}C AMS measurement results presented in this paper on wood charcoal provide precise dates which will be very useful not only to clarify the nature of human activities in this cave but also to provide reference dates when comparing other dating methods.

  17. Atmospheric 14 C CO 2 variations in Japan during 1982--1999 based on 14 C measurements of rice grains.

    Science.gov (United States)

    Shibata, Setsuko; Kawano, Eiko; Nakabayashi, Takeshige

    2005-08-01

    (14)C in rice grains is a useful tracer of atmospheric (14)C(CO(2)). (14)C measurement in rice grains for 17 years during 1982--1999 reveals the following. There is negative correlation between Delta(14)C and the population densities of localities in Japan. Under-populated areas in the northern area of Japan and Okinawa remained clean in the 1990s. The (14)C(CO(2)) decline rates at those areas are near to that of Shauinsland. A latitudinal effect due to Chinese nuclear tests is observed in 1982. Small Seuss effects is observed at the middle latitudes in East Asia after 1995.

  18. Fate of 14C-labelled compounds in marine environment

    International Nuclear Information System (INIS)

    Model ecosystems have played an important role in predicting environmental behavior of agrochemicals. The microcosms used in these studies generally include soil units containing usual biotic components common for that ecosystem. In present studies, scope of two such ecosystems has been extended to study the fate of 14C-labelled pesticides in marine environment. 14C-labelled pesticides used in these studies were chlorpyrifos, DDT and HCH. Two systems were developed in laboratory simulating marine environment to study the fate of these pesticides. The first system was developed in an all glass aquarium tank with marine sediments, seawater, clams and algae and is referred to as marine ecosystem. The second system was developed to permit the total 14C-mass balance studies. It contained marine sediments under moist (60% water holding capacity) or flooded conditions and it is referred to as continuous flow system. Fate of 14C-DDT was studied in marine ecosystem while degradation of 14C-chlorpyrifos and 14C-HCH was studied in continuous flow system. 14C-DDT did not bioaccumulate in clams while at the end of 60 days 50% of the applied 14C-activity was present in sediment fraction of marine ecosystem. 14C-HCH degradation showed about 22-26% mineralization while 45-55% of the applied activity was recovered as organic volatiles. No significant bound residues were formed. 14C-chorpyrifos underwent considerable degradation in marine environment. TCP was the major degradation product. (author)

  19. An overview of DNA fingerprinting with sup 32 P nucleotides

    Energy Technology Data Exchange (ETDEWEB)

    Pappas, G.G.

    1992-01-01

    The DNA probes radiolabeled with {sup 32}P, a primary tool employed by researchers in the life sciences for > 20 yr, are used by private companies, state-run laboratories, and the FBI to generate autoradiographs displaying the unique banding patterns that constitute the DNA fingerprint. The ability to identify an individual or animal from a biological sample has profound implications. Unidentified bodies, unrecognizable remains, and missing children can be tested and the DNA fingerprint compared to those of family members for positive identification. Paternity can be established before a child's birth. Immigration disputes can easily be resolved. Other uses include pedigree determination and testing for cell-line cross-contamination. Using a DNA fingerprint to determine the guilt or innocence of an individual allegedly involved in a violent crime is very controversial and has great legal and moral implications for society. Forensic laboratories have been challenged to ensure a level of quality control and quality assurance consistent with the weight given to these tests when used as evidence in a court of law.

  20. An overview of DNA fingerprinting with 32P nucleotides

    International Nuclear Information System (INIS)

    The DNA probes radiolabeled with 32P, a primary tool employed by researchers in the life sciences for > 20 yr, are used by private companies, state-run laboratories, and the FBI to generate autoradiographs displaying the unique banding patterns that constitute the DNA fingerprint. The ability to identify an individual or animal from a biological sample has profound implications. Unidentified bodies, unrecognizable remains, and missing children can be tested and the DNA fingerprint compared to those of family members for positive identification. Paternity can be established before a child's birth. Immigration disputes can easily be resolved. Other uses include pedigree determination and testing for cell-line cross-contamination. Using a DNA fingerprint to determine the guilt or innocence of an individual allegedly involved in a violent crime is very controversial and has great legal and moral implications for society. Forensic laboratories have been challenged to ensure a level of quality control and quality assurance consistent with the weight given to these tests when used as evidence in a court of law

  1. Transfer of 14C to prenatal and neonatal rats from their mothers exposed to 14C compounds by ingestion

    International Nuclear Information System (INIS)

    The transfer of 14C through placenta or milk was investigated and the radiation dose to fetal and newborn rats was estimated. Female rats at gestational stages or after delivery were exposed to 14C in the form of sodium bicarbonate, thymidine and lysine by a single ingestion. Radioactivity in maternal tissues and conceptuses (placenta, fetal membrane and fetus) and in the newborn was determined at various times after ingestion. After exposure to these 14C compounds, there was no significant difference between the 14C concentration in the fetus and that in the maternal tissues, suggesting that the placenta has no effect in preventing or accelerating the placental transfer of 14C. The concentration and content of 14C in the fetus and newborn were, however, dependent on the chemical form of 14C and on the prenatal or neonatal stage at the time of ingestion. The result of the dose estimation showed that 14C-lysine gave significantly higher prenatal and neonatal doses than 14C-sodium bicarbonate or 14C-thymidine. (author)

  2. Synthesis and quantitative biodistribution of a cardioprotective drug 35S-propargyl-cysteine (35S-SPRC)%心肌保护药物35S-SPRC的制备及其生物分布定量研究

    Institute of Scientific and Technical Information of China (English)

    沈海星; 张金莲; 孙丽; 朱建华

    2012-01-01

    目的 制备心肌保护药物35S-炔丙基半胱氨酸(35S-propargyl-cysteine,35S-SPRC)并以其为示踪剂研究SPRC在SD大鼠体内的生物学分布.方法 以半胱氨酸为起始原料合成非标记的SPRC,通过冷试验确定合成路线、反应条件及分析鉴定方法.在此基础上,以35S-L-半胱氨酸为原料合成35S-SPRC,35S-SPRC的鉴定采用TLC法及放射自显影法.按实验要求,将35S-SPRC配制成一定比活度的放射性溶液.取SD大鼠18只,随机分成3组,按15 mg/kg的剂量通过灌胃给药35S-SPRC.在不同时相将大鼠处死,取各脏器,称重、匀浆、消化,用液体闪烁计数器测定各样本的放射性活度.结果 最终产物35S-SPRC的TLC结果与SPRC完全一致,35S-SPRC的放化纯度大于95%.大鼠体内的生物学分布表明,35S-SPRC在大部分器官内0.5h达到峰值.结论 运用35S-SPRC能准确地测定SPRC在大鼠体内的生物分布.%Objective To prepare 35S-propargyl-cysteine (35S-SPRC) and through the isotopic tracer method to measure the biodistribution of SPRC in vivo of SD rats. Methods Non-radioactive labelled SPRC was synthesized by the starting material of cysteine and the synthetic route, reaction conditions and analytical identification were determined by the acquiration. On this basis,35S-L-cysteine was used to make 35S-SPRC, whose identification involved methods of TLC and phosphorus screen device autoradiography. To meet the experimental requirements,35 S-SPRC was prepared in certain specific activity and radioactive concentration. Eighteen SD rats were randomly divided into 3 groups.35 S-SPRC of 15 mg/kg was given intragastrically. The rats were killed at different time points with viscera organs first taken out, then homogenized, solubilized,and the liquid scintillation gauge was used to determine the radioactivity of each sample. Results TLC behavior of 35 S-SPRC was completely as same as SPRCwith its radiochemical purity being higher than 95%. The biological

  3. Brachytherapy on restenosis. {sup 32}P radioisotope in animal model

    Energy Technology Data Exchange (ETDEWEB)

    Bergoc, R.; Rivera, E.; Cocca, C.; Martin, G.; Cricco, G. [Buenos Aires Univ. (Argentina). School of Pharmacy and Biochemistry; Croci, M.; Guzman, L.

    2000-05-01

    Despite a notorious decline in age-adjusted death rates for cardiovascular pathologies, coronary artery disease still remains as the main cause of mortality above the age of 40 in men and 60 in women. More than 25% of death in persons over the age of 35 are due to coronary disease. In about 50% of men and 30% of women, the first manifestation of the disease is an acute myocardial infarction and 10% a sudden cardiac death. In Argentina it is estimated that in 1998 about 100.000-115.000 people suffered as first manifestation of coronary illness a myocardial acute infarct. Angioplasty has an important and well established site in the treatment of the coronary illness and restenosis represents the principal complication of this method for myocardial re-vascularization. About a 35-40% of treated arteries present restenosis within the first six month the intervention with the concomitant need of re-interventions, re-hospitalizations, by-pass surgery, work discontinuity and the high cost for the health system. A number of drugs were tested as anti-restenosis: anticoagulants, aspirin, antispasmodics and lipid-lowering agents but none was clearly efficient; also, experimental studies in which intravascular irradiation with different source types and energies, radiation doses and doses rate to prevent restenosis was utilized; however, there is no consensus in many aspects of this intravascular brachytherapy. The first step in this work was to induce the experimental model in rabbits. Afterwards, by means of the balloon methodology and stent implantation, brachytherapy experiments were carried out to evaluate the biological effect on different layers of arteries, with different Doses using a beta particle emitting radioisotope ({sup 32}P). The arteriosclerotic lesions were induced in New Zealand rabbits through the administration of a diet with high cholesterol content. Angioplastic interventions on femoral arteries were done with balloon methodology and controlled by

  4. Brachytherapy on restenosis. 32P radioisotope in animal model

    International Nuclear Information System (INIS)

    Despite a notorious decline in age-adjusted death rates for cardiovascular pathologies, coronary artery disease still remains as the main cause of mortality above the age of 40 in men and 60 in women. More than 25% of death in persons over the age of 35 are due to coronary disease. In about 50% of men and 30% of women, the first manifestation of the disease is an acute myocardial infarction and 10% a sudden cardiac death. In Argentina it is estimated that in 1998 about 100.000-115.000 people suffered as first manifestation of coronary illness a myocardial acute infarct. Angioplasty has an important and well established site in the treatment of the coronary illness and restenosis represents the principal complication of this method for myocardial re-vascularization. About a 35-40% of treated arteries present restenosis within the first six month the intervention with the concomitant need of re-interventions, re-hospitalizations, by-pass surgery, work discontinuity and the high cost for the health system. A number of drugs were tested as anti-restenosis: anticoagulants, aspirin, antispasmodics and lipid-lowering agents but none was clearly efficient; also, experimental studies in which intravascular irradiation with different source types and energies, radiation doses and doses rate to prevent restenosis was utilized; however, there is no consensus in many aspects of this intravascular brachytherapy. The first step in this work was to induce the experimental model in rabbits. Afterwards, by means of the balloon methodology and stent implantation, brachytherapy experiments were carried out to evaluate the biological effect on different layers of arteries, with different Doses using a beta particle emitting radioisotope (32P). The arteriosclerotic lesions were induced in New Zealand rabbits through the administration of a diet with high cholesterol content. Angioplastic interventions on femoral arteries were done with balloon methodology and controlled by fluoroscopy

  5. Synthesis of psilocin labelled with 14C and 3H

    International Nuclear Information System (INIS)

    14C- and 3H-labelled psilocin (4-hydroxy-N,N-dimethyl-tryptamine), the principal, active agent of hallucinogenic mushrooms, was synthesized from 2-methyl-3-nitrophenol via 4-benzyloxyindole. 14C-Labelled potassium cyanide was reacted with 4-benzyloxygramine (obtained from 4-benzyloxyindole) to give 14C-4-benzyloxy-3-indole acetic acid, an intermediate for 14C-psilocin synthesis. 3H-Labelled lithium aluminium hydride was used to react with 4-benzyloxy-3-indole-N,N-dimethyl-glyoxylamide (obtained from 4-benzyloxyindole) to give 3H-4-benzyloxy-psilocin which was debenzylated to form 3H-psilocin. (author)

  6. Increased [32P]-phosphorylation of tryptic peptides of erythrocyte spectrin in Duchenne muscular dystrophy

    International Nuclear Information System (INIS)

    Increased [32P]-incorporation in tryptic peptides of the erythrocyte membrane protein spectrin Band 2 in Duchenne muscular dystrophy (DMD) was studied in a consecutive series of 10 matched DMD/control pairs. Spectrin was [32P]-phosphorylated by cyclic AMP-independent endogenous membrane protein kinase in the presence of [gamma-32P]ATP. [32P]-labeled spectrin was isolated, purified, and subjected to tryptic cleavage with excess trypsin. The resulting peptides were separated on a high-resolution 5%/15% stacking SDS--polyacrylamide gel electrophoresis system. Liquid scintillation counting was performed on sequential slices of unstained gels. A broad [32P]-labeled band containing a number of [32P]-polypeptides was found to be more highly [32P]-phosphorylated in DMD patients than in their matched controls. This band migrated with an apparent molecular mass of 4.8-5.2 kilodaltons and contained approximately 55% of total [32P] radioactivity covalently bound to spectrin peptides. These data demonstrated an increased [32P]-phosphorylation of an identifiable tryptic peptide fraction in DMD that is consistent with previous reports of increased spectrin Band 2 [32P]-phosphorylation in DMD

  7. Synthesis of /sup 14/C-propoxur (o-isopropoxyphenyl N-methylcarbamate-/sup 14/C) insecticide

    Energy Technology Data Exchange (ETDEWEB)

    Hossaini, M.A.; Zareh, Z. (Atomic Energy Organization of Iran, Teheran. Nuclear Research Centre)

    1984-08-01

    /sup 14/C-propoxur (Baygonsub(circled R)) is an insecticide with a broad spectrum of activity and a very low order of mammalian toxicity. Radiosynthesis of propoxur was performed by the reaction of acetyl-1-/sup 14/C chloride and sodium azide to produce methyl isocyanate which then reacted with o-isopropoxyphenol at 100 degC. A two-compartment reaction tube with a break seal was utilized. Chromatograhic procedures for isolating the N-methylcarbamates from their reaction mixtures are reported. Acetyl-1-/sup 14/C chloride was prepared from thionyl chloride and sodium acetate-1-/sup 14/C. Grignard reaction between methyl iodide and carbon-14 dioxide yielded acetic acid-/sup 14/C which was neutralized by sodium hydroxide solution to give sodium acetate-1-/sup 14/C. 9 refs.

  8. Root-uptake of {sup 14}C derived from acetic acid and {sup 14}C transfer to rice edible parts

    Energy Technology Data Exchange (ETDEWEB)

    Ogiyama, Shinichi [Office of Biospheric Assessment for Waste Disposal, National Institute of Radiological Sciences, 4-9-1 Anagawa, Inage-ku, Chiba-shi 263-8555 (Japan)], E-mail: ogiyama@nirs.go.jp; Suzuki, Hiroyuki [Graduate School of Pharmaceutical Sciences, Chiba University, 1-33 Yayoi-cho, Inage-ku, Chiba-shi 263-5522 (Japan); Inubushi, Kazuyuki [Graduate School of Horticulture, Chiba University, 648 Matsudo, Matsudo-shi 271-8510 (Japan); Takeda, Hiroshi; Uchida, Shigeo [Office of Biospheric Assessment for Waste Disposal, National Institute of Radiological Sciences, 4-9-1 Anagawa, Inage-ku, Chiba-shi 263-8555 (Japan)

    2010-02-15

    Three types of culture experiments using paddy rice (Oryza sativa L.) were performed to examine root-uptake of {sup 14}C in the form of acetic acid: double pot experiment (hydroponics), wet culture experiment (submerged sand medium), and chamber experiment (hydroponics and submerged sand medium). The {sup 14}C radioactivity in the plant, mediums, and atmospheric carbon dioxide ({sup 14}CO{sub 2}) in the chamber were determined, and the distribution of {sup 14}C in the plant was visualized using autoradiography. In the double pot experiment, the shoot of the plant and the lower root which was soaked in the culture solution had {sup 14}C radioactivity, but the upper root which did not have contact with the solution had none. There were also {sup 14}C radioactivity in the grains and roots in the wet culture experiment. Results of the chamber experiment showed that {sup 14}CO{sub 2} gas was released from the culture solution in both types of cultures. Results indicated that the {sup 14}C-acetic acid absorbed by rice plant through its root would be very small. Most of the {sup 14}C-acetic acid was transformed into gaseous forms either in the culture solution or rhizosphere. A relatively longer time would be needed to assimilate {sup 14}C derived from acetic acid to grain parts after it was once absorbed by the shoot through the root. Availability of {sup 14}C for the plant in sand culture was considered to be decreased compared with that for the plant in the hydroponics experiment. It was suggested that rice plant absorbed and assimilated {sup 14}C through the plant roots not because of uptake of {sup 14}C-acetic acid but because of uptake of {sup 14}C in gaseous forms such as {sup 14}CO{sub 2}.

  9. Root-uptake of 14C derived from acetic acid and 14C transfer to rice edible parts

    International Nuclear Information System (INIS)

    Three types of culture experiments using paddy rice (Oryza sativa L.) were performed to examine root-uptake of 14C in the form of acetic acid: double pot experiment (hydroponics), wet culture experiment (submerged sand medium), and chamber experiment (hydroponics and submerged sand medium). The 14C radioactivity in the plant, mediums, and atmospheric carbon dioxide (14CO2) in the chamber were determined, and the distribution of 14C in the plant was visualized using autoradiography. In the double pot experiment, the shoot of the plant and the lower root which was soaked in the culture solution had 14C radioactivity, but the upper root which did not have contact with the solution had none. There were also 14C radioactivity in the grains and roots in the wet culture experiment. Results of the chamber experiment showed that 14CO2 gas was released from the culture solution in both types of cultures. Results indicated that the 14C-acetic acid absorbed by rice plant through its root would be very small. Most of the 14C-acetic acid was transformed into gaseous forms either in the culture solution or rhizosphere. A relatively longer time would be needed to assimilate 14C derived from acetic acid to grain parts after it was once absorbed by the shoot through the root. Availability of 14C for the plant in sand culture was considered to be decreased compared with that for the plant in the hydroponics experiment. It was suggested that rice plant absorbed and assimilated 14C through the plant roots not because of uptake of 14C-acetic acid but because of uptake of 14C in gaseous forms such as 14CO2.

  10. The use of 14C ethanolamine as a precursor

    International Nuclear Information System (INIS)

    Two new 2 chloroethyl nitrosoureas were labelled on two positions by 14C starting from Na14CN and using 14C ethanolamine as intermediate, i.e. on the carbon 2 of the 2 chloro ethyl group and on the carbon 2 of the cysteamine part. (author)

  11. Irradiation Scheme Design of 14C Production on CARR

    Institute of Scientific and Technical Information of China (English)

    SUN; Zheng; LIU; Xing-min; XU; Zhi-long; DING; Li

    2012-01-01

    <正>14C is a radioisotope of carbon. It is widely used in pharmacy, medical treatment, agriculture, reconnoiter and archaeology. China Advanced Research Reactor (CARR) is a research reactor of high capability, the applications of which includes the radio nuclides production. Therefore, the technical scheme on 14C irradiation in CARR should be prepared elaborately.

  12. Percutaneous absorption of [14C]DDT and [14C]benzo[a]pyrene from soil

    International Nuclear Information System (INIS)

    The objective was to determine percutaneous absorption of DDT and benzo[a]pyrene in vitro and in vivo from soil into and through skin. Soil (Yolo County 65-California-57-8; 26% sand, 26% clay, 48% silt) was passed through 10-, 20-, and 48-mesh sieves. Soil then retained by 80-mesh was mixed with [14C]-labeled chemical at 10 ppm. Acetone solutions at 10 ppm were prepared for comparative analysis. Human cadaver skin was dermatomed to 500 microns and used in glass diffusion cells with human plasma as the receptor fluid (3 ml/hr flow rate) for a 24-hr skin application time. With acetone vehicle, DDT (18.1 +/- 13.4%) readily penetrated into human skin. Significantly less DDT (1.0 +/- 0.7%) penetrated into human skin from soil. DDT would not partition from human skin into human plasma in the receptor phase (less than 0.1%). With acetone vehicle, benzo[a]pyrene (23.7 +/- 9.7%) readily penetrated into human skin. Significantly less benzo[a]pyrene (1.4 +/- 0.9%) penetrated into human skin from soil. Benzo[a]pyrene would not partition from human skin into human plasma in the receptor phase (less than 0.1%). Substantivity (skin retention) was investigated by applying 14C-labeled chemical to human skin in vitro for only 25 min. After soap and water wash, 16.7 +/- 13.2% of DDT applied in acetone remained absorbed to skin. With soil only 0.25 +/- 0.11% of DDT remained absorbed to skin. After soap and water wash 5.1 +/- 2.1% of benzo[a]pyrene applied in acetone remained absorbed to skin. With soil only 0.14 +/- 0.13% of benzo[a]pyrene remained absorbed to skin

  13. Radiocarbon 14C differentiation of sparkling and carbonated wines

    International Nuclear Information System (INIS)

    Specific 14C-activities, percent of modern 14C-activity, and calculated percent of fermentation CO2 are presented for CO2 contained in commercial sparkling wines, labeled as champagne or produced by the bulk (charmat) process. These data are given for the production years 1976-1982. The survey encompassed effervescent wines produced in Spain, Italy, West Germany, California, and New York. Addition of synthetic CO2 to approximately 40 samples represented as sparkling wines was indicated by low 14C-activities of CO2 in these wines. Data for 14C-activity were also presented for the ethanol distilled from sparkling wines for the years 1977-1980. In all cases, the 14C-activity of ethanol was appropriate to the year of vintage

  14. Determination of phagocytosis of 32P-labeled Staphylococcus aureus by bovine polymorphonuclear leukocytes

    International Nuclear Information System (INIS)

    A procedure for the measurement of phagocytosis by bovine polymorphonuclear leukocytes (PMN) of 32P-labeled Staphylococcus aureus was modified so that a larger number of samples could be compared in a single run, and smaller volumes of sample, PMN, and 32P-labeled S aureus could be used. Results were highly reproducible, with a coefficient of variation between duplicate determinations of less than or equal to 2%. Lysostaphin was prepared from the supernatant of S staphylolyticus and was compared with a commercially available preparation. Effects of lysostaphin on PMN and influence of incubation media on release of 32P from 32P-labeled S aureus by lysostaphin were examined

  15. Myo-inositol-14C, phytic acid-14C and ferric phytate-14C metabolism through microbian action in an andosol soil

    International Nuclear Information System (INIS)

    The myo-inositol-14C, phytic acid-14C and ferric phytate-14C compounds were incubated in an andosol soil at 70% of the field capacity and at 36.5 deg C during twelve days. These compounds suffered a microbian oxidation at 14CO2 of 61.0, 1.9 and 0% respectively. The fixation of the phytic acid-14C was observed through the fast decrease in the metabolism, due to the formation of complexes with the Fe and Al (phytates). The myo-inositol-14C metabolism was reduced by a factor of nine at the second incubation day. The following mechanisms were observed in the myo-inositol metabolism: (i) adsorption of the inositol by the soil minerals, (ii) adsorption by humic acids, (iii) myo-inositol phosphorylation and (iv) epimerization of myo-inositol to chiro-inositol. It was found that the (i) and (ii) formation depends on the soil microbian activity. The (i), (ii) and (iii) interactions were considered as possible mechanisms for the inhibition of the myo-inositol microbian oxidation. The inhibition of the myo-inositol oxidation through adsorption or phosphorylation is considered as a chemical blockade for the hydroaxial group, avoiding this way a microbian oxidation stereospecific of this hydroxil group. (author)

  16. Helicobacter pylori infection studies using 14C UBT method

    International Nuclear Information System (INIS)

    Carbon 14 (14C) is a naturally occurring radioactive isotope of carbon. The half-life of 14C is about 5,730 years, and it decays by emitting a low energy beta (â) particle of mean energy 49 KeV. The biological half life of 14C is 10 to 12 days. 14C is present in the environment and in all organic materials and behaves in the environment in the same manner as other carbon isotopes. In medicine, 14C can be injected to study abnormalities of metabolism that underlie diabetes, gout, anaemia and acromegaly (adult 'gigantism'), and for diagnosis of Helicobacterpylori (H pylori), The discovery H Pylori by Warren and Marshall in 1982 changed the approach to treat peptic ulcer disease (PUD), Since then H pylori has been the focus of clinical research and debate. The causal relationship between H pylori infection and chronic gastritis is well established, H pylori infection is one of the most common human infections worldwide. This organism has been shown to infect over half of the world's population. By the application of radiation much progress has been made worldwide in the field of medicine. This article presents the application of 14C Urea Breath Test (14C UBT) for the diagnosis of the H pylori bacteria which present in the stomach and duodenum, 14C UBT relies on the urease activity of H pylori to detect the presence of active infection. Board of Radiation and Isotope Technology (BRIT), Mumbai has developed 14C UBT method and already in regular practice in many hospitals across the country. Orally administered 14C urea will be hydrolyzed into ammonia (NH4) and 14C labelled carbon dioxide (14CO2). The presence of a significant amount of (14CO2) in the exhaled breath indicates active H pylori infection. 14C UBT is relatively inexpensive, is easy to perform, and does not require endoscopy. 14C UBT has proved to be one of the most accurate methods for assessing H pylori status. The ionizing radiation dose involved in this test is extremely low, much lower than the

  17. 14C-age tracers in global ocean circulation models

    Science.gov (United States)

    Koeve, W.; Wagner, H.; Kähler, P.; Oschlies, A.

    2015-07-01

    The natural abundance of 14C in total CO2 dissolved in seawater (DIC) is a property applied to evaluate the water age structure and circulation in the ocean and in ocean models. In this study we use three different representations of the global ocean circulation augmented with a suite of idealised tracers to study the potential and limitations of using natural 14C to determine water age, which is the time elapsed since a body of water has been in contact with the atmosphere. We find that, globally, bulk 14C-age is dominated by two equally important components, one associated with ageing, i.e. the time component of circulation, and one associated with a "preformed 14C-age". The latter quantity exists because of the slow and incomplete atmosphere-ocean equilibration of 14C particularly in high latitudes where many water masses form. In the ocean's interior, preformed 14C-age behaves like a passive tracer. The relative contribution of the preformed component to bulk 14C-age varies regionally within a given model, but also between models. Regional variability in the Atlantic Ocean is associated with the mixing of waters with very different end members of preformed 14C-age. Here, variations in the preformed component over space and time mask the circulation component to an extent that its patterns are not detectable from bulk 14C-age. Between models, the variability of preformed 14C-age can also be considerable (factor of 2), related to the combination of physical model parameters, which influence circulation dynamics or gas exchange. The preformed component was found to be very sensitive to gas exchange and moderately sensitive to ice cover. In our model evaluation, the choice of the gas-exchange constant from within the currently accepted range of uncertainty had such a strong influence on preformed and bulk 14C-age that if model evaluation would be based on bulk 14C-age, it could easily impair the evaluation and tuning of a model's circulation on global and regional

  18. Effects of Pseudomonas species on the release of bound 14C residues from soil treated with [14C]atrazine

    International Nuclear Information System (INIS)

    The release of bound (nonextractable) 14C residues from soil previously treated with [14C]atrazine was investigated by incubation of the solvent-extracted soil with two species of Pseudomonas capable of metabolizing atrazine. The two species, 192 and 194, released bound 14C residues from the soil. Addition of glucose, known to increase microbiological activities, to the incubated soil appeared to enhance the release of soil-bound 14C residues, in particular in the presence of Pseudomonas species 192. The 14C bound residues in soil, mainly present as the parent compound and its hydroxy and monodealkylated analogues, were released into the incubation mixture and were subsequently metabolized by the two species involving dechlorination and dealkylation

  19. TMEM14C is required for erythroid mitochondrial heme metabolism.

    Science.gov (United States)

    Yien, Yvette Y; Robledo, Raymond F; Schultz, Iman J; Takahashi-Makise, Naoko; Gwynn, Babette; Bauer, Daniel E; Dass, Abhishek; Yi, Gloria; Li, Liangtao; Hildick-Smith, Gordon J; Cooney, Jeffrey D; Pierce, Eric L; Mohler, Kyla; Dailey, Tamara A; Miyata, Non; Kingsley, Paul D; Garone, Caterina; Hattangadi, Shilpa M; Huang, Hui; Chen, Wen; Keenan, Ellen M; Shah, Dhvanit I; Schlaeger, Thorsten M; DiMauro, Salvatore; Orkin, Stuart H; Cantor, Alan B; Palis, James; Koehler, Carla M; Lodish, Harvey F; Kaplan, Jerry; Ward, Diane M; Dailey, Harry A; Phillips, John D; Peters, Luanne L; Paw, Barry H

    2014-10-01

    The transport and intracellular trafficking of heme biosynthesis intermediates are crucial for hemoglobin production, which is a critical process in developing red cells. Here, we profiled gene expression in terminally differentiating murine fetal liver-derived erythroid cells to identify regulators of heme metabolism. We determined that TMEM14C, an inner mitochondrial membrane protein that is enriched in vertebrate hematopoietic tissues, is essential for erythropoiesis and heme synthesis in vivo and in cultured erythroid cells. In mice, TMEM14C deficiency resulted in porphyrin accumulation in the fetal liver, erythroid maturation arrest, and embryonic lethality due to profound anemia. Protoporphyrin IX synthesis in TMEM14C-deficient erythroid cells was blocked, leading to an accumulation of porphyrin precursors. The heme synthesis defect in TMEM14C-deficient cells was ameliorated with a protoporphyrin IX analog, indicating that TMEM14C primarily functions in the terminal steps of the heme synthesis pathway. Together, our data demonstrate that TMEM14C facilitates the import of protoporphyrinogen IX into the mitochondrial matrix for heme synthesis and subsequent hemoglobin production. Furthermore, the identification of TMEM14C as a protoporphyrinogen IX importer provides a genetic tool for further exploring erythropoiesis and congenital anemias.

  20. Dating human DNA with the 14C bomb peak

    Energy Technology Data Exchange (ETDEWEB)

    Kutschera, Walter; Liebl, Jakob; Steier, Peter [VERA Laboratory, University of Vienna, Vienna (Austria)

    2013-07-01

    In 1963 the limited nuclear test ban treaty stopped nuclear weapons testing in the atmosphere. By then the addition from bomb-produced {sup 14}C had doubled the {sup 14}C content of the atmosphere. Through the CO{sub 2} cycle this excess exchanged with the hydrosphere and biosphere leading to a rapidly decreasing {sup 14}C level in the atmosphere. Today we are almost back to the pre-nuclear level. As a consequence all people on Earth who lived during the second half of the 20th century were exposed to this rapidly changing {sup 14}C signal. A few years ago, a group at the Department of Cell and Molecular Biology of the Karolinska Institute in Stockholm started to use the {sup 14}C bomb peak signal in DNA to determine retrospectively the age of cells from various parts of the human body (brain, heart, fat). In a collaboration with this group, we have studied the age of olfactory bulb neurons in the human brain. For this investigation, {sup 14}C AMS measurements were developed at VERA for very small carbon samples in the range from 2 to 4 micrograms. In the presentation the general concept of {sup 14}C bomb peak dating of human DNA and several applications are discussed.

  1. TMEM14C is required for erythroid mitochondrial heme metabolism

    Science.gov (United States)

    Yien, Yvette Y.; Robledo, Raymond F.; Schultz, Iman J.; Takahashi-Makise, Naoko; Gwynn, Babette; Bauer, Daniel E.; Dass, Abhishek; Yi, Gloria; Li, Liangtao; Hildick-Smith, Gordon J.; Cooney, Jeffrey D.; Pierce, Eric L.; Mohler, Kyla; Dailey, Tamara A.; Miyata, Non; Kingsley, Paul D.; Garone, Caterina; Hattangadi, Shilpa M.; Huang, Hui; Chen, Wen; Keenan, Ellen M.; Shah, Dhvanit I.; Schlaeger, Thorsten M.; DiMauro, Salvatore; Orkin, Stuart H.; Cantor, Alan B.; Palis, James; Koehler, Carla M.; Lodish, Harvey F.; Kaplan, Jerry; Ward, Diane M.; Dailey, Harry A.; Phillips, John D.; Peters, Luanne L.; Paw, Barry H.

    2014-01-01

    The transport and intracellular trafficking of heme biosynthesis intermediates are crucial for hemoglobin production, which is a critical process in developing red cells. Here, we profiled gene expression in terminally differentiating murine fetal liver-derived erythroid cells to identify regulators of heme metabolism. We determined that TMEM14C, an inner mitochondrial membrane protein that is enriched in vertebrate hematopoietic tissues, is essential for erythropoiesis and heme synthesis in vivo and in cultured erythroid cells. In mice, TMEM14C deficiency resulted in porphyrin accumulation in the fetal liver, erythroid maturation arrest, and embryonic lethality due to profound anemia. Protoporphyrin IX synthesis in TMEM14C-deficient erythroid cells was blocked, leading to an accumulation of porphyrin precursors. The heme synthesis defect in TMEM14C-deficient cells was ameliorated with a protoporphyrin IX analog, indicating that TMEM14C primarily functions in the terminal steps of the heme synthesis pathway. Together, our data demonstrate that TMEM14C facilitates the import of protoporphyrinogen IX into the mitochondrial matrix for heme synthesis and subsequent hemoglobin production. Furthermore, the identification of TMEM14C as a protoporphyrinogen IX importer provides a genetic tool for further exploring erythropoiesis and congenital anemias. PMID:25157825

  2. 14C-carbaryl residues in cotton seed products

    International Nuclear Information System (INIS)

    14C-Methyl and 14C-ring-labelled carbaryl were used to study the magnitude and fate of the insecticide residues in cotton seed products and in the plant. 14C-Residues were found to be 0.08-0.09, 0.23-0.30 and 0.05 ppm in the seed, oil and cake respectively. In the oil, the residue was resolved into four compounds two of which were identified as carbaryl and 1-naphthol. Residues taken up from the soil did not exceed 0.3 ppm after the first week and declined to 0.1 ppm after five weeks. (author)

  3. Radiophosphorus (/sup 32/P) treatment of bone marrow disorders in dogs: 11 cases (1970-1987)

    Energy Technology Data Exchange (ETDEWEB)

    Smith, M.; Turrel, J.M.

    1989-01-01

    Between March 1970 and February 1987, radiophosphorus (/sup 32/P) was used to treat bone marrow disorders in 6 dogs; 4 had polycythemia vera and 2 had essential thrombocythemia. Activities of /sup 32/P given initially ranged from 2.4 to 3.3 mCi/m2. Four dogs responded well to /sup 32/P treatment, with gradual resolution of high RBC or platelet counts. Two of these dogs died of intercurrent disease unrelated to their bone marrow disorder, before blood counts could be stabilized. Two dogs did not respond to the initial /sup 32/P treatment nor to additional treatments with /sup 32/P, and had clinical signs and blood counts stabilized by use of phlebotomy or chemotherapeutic agents. We reviewed and analyzed 5 other cases of bone marrow disorders in dogs treated with /sup 32/P and included the findings from their records with the records of our 6 dogs in this retrospective analysis. Of the 8 dogs with polycythemia vera treated with /sup 32/P, 5 were given a single treatment that controlled clinical signs and blood counts for the remainder of the follow-up period. Of the 3 dogs treated for thrombocytosis with /sup 32/P, 2 had blood counts that responded to a single treatment.

  4. Forensic applications of 14C bomb-pulse dating

    International Nuclear Information System (INIS)

    After a brief review of the basics of 14C bomb-pulse dating, this paper presents two unique forensic applications. Particular attention is dedicated to the use of the 14C bomb-pulse to establish the time of harvest of illicit drugs such as heroin and opium. Preliminary measurements of 14C concentrations in milligram samples taken from seized drugs are presented. 14C bomb-pulse dating can determine whether drug distribution originates from stockpiles or recent manufacture, and support the action of law enforcement authorities against criminal organisations involved in drug trafficking. In addition, we describe the dating of wine vintages for a number of authenticated single label vintage red wines from the Barossa Valley - South Australia. Our results show that radiocarbon dating can be used to accurately determine wine vintages and therefore reveal the addition of unrelated materials of natural and synthetic origin

  5. Residues of 14C-cyolane in cottonseed products

    International Nuclear Information System (INIS)

    The systemic insecticide cyolane [2-(0,0-diethylphosphoryl)-imino-1,3-dithiolane] was prepared from 14C-ethanol, phosphorus oxychloride and 2-amino-1,3-dithiolane. Cotton plants were treated with two applications of the insecticide under conditions of local agricultural practice. 14C-residues in the crude oil and cake of the harvested cotton seeds amounted to 1.63 and 0.014 mg/kg respectively. About 50% of the 14C-activity present in the crude oil was found to be eliminated by simulated commercial processes used for refining of the oil. Alkali treatment and bleaching removed 16% and 25% of the radioactive residues respectively. Winterization of the bleached oil at 5-70C for 3 days effected a further elimination of 13%. 14C-residues in the cotton seed products and in the samples of the refined oil were characterized and the main constituents identified using chromatographic techniques. (author)

  6. Forensic applications of {sup 14}C bomb-pulse dating

    Energy Technology Data Exchange (ETDEWEB)

    Zoppi, U. E-mail: ugo@ansto.gov.au; Skopec, Z.; Skopec, J.; Jones, G.; Fink, D.; Hua, Q.; Jacobsen, G.; Tuniz, C.; Williams, A

    2004-08-01

    After a brief review of the basics of {sup 14}C bomb-pulse dating, this paper presents two unique forensic applications. Particular attention is dedicated to the use of the {sup 14}C bomb-pulse to establish the time of harvest of illicit drugs such as heroin and opium. Preliminary measurements of {sup 14}C concentrations in milligram samples taken from seized drugs are presented. {sup 14}C bomb-pulse dating can determine whether drug distribution originates from stockpiles or recent manufacture, and support the action of law enforcement authorities against criminal organisations involved in drug trafficking. In addition, we describe the dating of wine vintages for a number of authenticated single label vintage red wines from the Barossa Valley - South Australia. Our results show that radiocarbon dating can be used to accurately determine wine vintages and therefore reveal the addition of unrelated materials of natural and synthetic origin.

  7. Patient risk of 14C-urea breath test

    International Nuclear Information System (INIS)

    Helicobacter Pylori bacteria infection is determined by activity measurement of the exhaled 14C-carbon dioxide formed from 14C-urea in stomach. About 37 kBq of capsulated 14C -urea is administered to the patient. Because 14C is a weak beta emitter, patients receive certain radiation dose. This could be the only drawback of this method. Because of that in this paper the effective dose has been determined. On that basis the patient risk has been estimated. The results show that the patient effective dose is at the level of the daily background radiation. So, from the radiation protection point of view this method is very safe. Including other excellent performances of the method like sensitivity, selectivity, noninvasivity, fastness and low costs, it could be recommended in diagnosis and eradication of Helicobacter Pylori infections. (author)

  8. 14C-age tracers in global ocean circulation models

    Directory of Open Access Journals (Sweden)

    W. Koeve

    2014-10-01

    Full Text Available The natural abundance of 14C in total CO2 dissolved in seawater is a property applied to evaluate the water age structure and circulation in the ocean and in ocean models. In this study we use three different representations of the global ocean circulation augmented with a suite of idealised tracers to study the potential and limitations of using natural 14C to determine water age, the time elapsed since a body of water had contact with the atmosphere. We find that, globally, bulk 14C-age is dominated by two equally important components, one associated with aging, i.e. the time component of circulation and one associated with a "preformed 14C-age". This latter quantity exists because of the slow and incomplete atmosphere/ocean equilibration of 14C in particular in high latitudes where many water masses form. The relative contribution of the preformed component to bulk 14C-age varies regionally within a given model, but also between models. Regional variability, e.g. in the Atlantic Ocean is associated with the mixing of waters with very different end members of preformed 14C-age. In the Atlantic, variations in the preformed component over space and time mask the circulation component to an extent that its patterns are not detectable from bulk 14C-age alone. Between models the variability of age can also be considerable (factor of 2, related to the combinations of physical model parameters, which influence circulation dynamics, and gas exchange in the models. The preformed component was found to be very sensitive to gas exchange and moderately sensitive to ice cover. In our model evaluation exercise, the choice of the gas exchange constant from within the current range of uncertainty had such a strong influence on preformed and bulk 14C-age that if model evaluation would be based on bulk 14C-age it could easily impair the evaluation and tuning of a models circulation on global and regional scales. Based on the results of this study, we propose

  9. Synthesis of [14C]-labelled dihydropyridine calcium channel entry blockers: nicardipine-[4[14C] and RS-93522-[4-14C

    International Nuclear Information System (INIS)

    The Hantzsch synthesis has been applied to the general preparation of 4-aryl-dihydropyridines labelled in the metabolically stable 4-position of the dihydropyridine ring. The synthesis is based on the preparation of a key common intermediate, m-nitrobenzaldehyde-[formyl-14C], in high yield from Ba14CO3. (author)

  10. {sup 14}C in human diet in three Spanish locations; {sup 14}C en dieta humana en tres localizaciones espanolas

    Energy Technology Data Exchange (ETDEWEB)

    Gomez Martinez, I.; Santos Arevalo, F. J.; Manjon, G.; Garcia-Tenorio, R.

    2011-07-01

    {sup 14}C reach humans via the diet. In this study we present the results of diet samples from three locations type Spanish, Seville, Caceres and Tenerife. These diets are collected quarterly and historical dates back to early 2008.

  11. A modified method for synthesis of [γ-32P] labelled adenosine triphosphate

    International Nuclear Information System (INIS)

    Production of [γ-32P]-ATP using three glycolysis enzymatic reaction i.e. glyceraldehyde 3-phosphate dehydrogenase, 3-phosphoglyceric phosphokinase and lactate dehydrogenase has been conducted. dl-glyceraldehyde 3-phosphate, Adenosine Diphosphate and H332PO4 was used as precursors for this reaction. Purification of [γ-32P]-ATP was performed by using DEAE-Sephadex column chromatography. The result suggested that this simple method could be used for producing [γ-32P]-ATP to support the provision of radiolabeled nucleotide for biotechnology research in Indonesia. (author)

  12. Study on the dynamics in absorption of 32P by hybrid wheat at elongate stage

    International Nuclear Information System (INIS)

    The dynamics of absorbing 32P of hybrid wheat at elongate stage is studied under pot culture conditions. The results show that the absorption capacity of hybrid wheat to 32P is in agreement with regression equation. The increased extent of absorption for them is greater than that for parent with time, and the reduction rate of absorption is lower than the parent significantly. Their root activity is much higher than that of the parent, too. The overall heterotic vigor of hybrid wheat on the absorption capacity to 32P is the sum of that of all organs

  13. Algal photosynthetic activity measurement by 14C uptake, (1)

    International Nuclear Information System (INIS)

    There are many sample preparation techniques for 14C-labeled phytoplankton for radioactivity measurement by liquid scintillation counting. A number of sample preparation procedures were tested to identify the ones most suitable for the intended experiments. The following results were obtained: 1. The calculated radioactivity of solubilized samples were about 10% lower than that of combusted samples. This was caused by settling out of algal cells. 2. The agreement between calculated radioactivity of solubilized samples and combusted samples was improved by the addition of Cab-O-Sil. 3. Virtually all of the residual inorganic 14C radioactivity was removed during drying. 4. The loss of 14C radioactivity caused by formaldehyde fixation differed from species to species. Based on these results, the following procedure was selected for use in our experiments: 1. After incubation with 14C, the 14C-labeled phytoplankton samples were immediately filtered and rinsed with filtered seawater under low illumination. 2. The filters were then dried in a vacuum desiccator with sodalime and silica gel. 3. The dried filters were solubilized with ethylene glycol monomethyl ether-toluene fluor which contains PPO, POPOP, and Cab-O-Sil. 4. The activity of solubilized samples was measured using liquid scintillation counting. (author)

  14. Measuring the 14C content in liquid scintillators

    Science.gov (United States)

    Enqvist, T.; Barabanov, I. R.; Bezrukov, L. B.; Gangapshev, A. M.; Gavrilyuk, Y. M.; Grishina, V. Yu; Gurentsov, V. I.; Hissa, J.; Joutsenvaara, J.; Kazalov, V. V.; Krokhaleva, S.; Kutuniva, J.; Kuusiniemi, P.; Kuzminov, V. V.; Kurlovich, A. S.; Loo, K.; Lubsandorzhiev, B. K.; Lubsandorzhiev, S.; Morgalyuk, V. P.; Novikova, G. Y.; Pshukov, A. M.; Sinev, V. V.; Słupecki, M.; Trzaska, W. H.; Umerov, Sh I.; Veresnikova, A. V.; Virkajärvi, A.; Yanovich, Y. A.; Zavarzina, V. P.

    2016-05-01

    We are going to perform a series of measurements where the 14C/12 C ratio will be measured from several liquid scintillator samples with a dedicated setup. The setup is designed with the aim of measuring ratios smaller than 10-18. Measurements take place in two underground laboratories: in the Baksan Neutrino Observatory, Russia and in the Pyhäsalmi mine, Finland. In Baksan the measurements started in 2015 and in Pyhäsalmi they start in the beginning of 2015. In order to fully understand the operation of the setup and its background contributions a development of simulation packages has also been started. Low-energy neutrino detection with a liquid scintillator requires that the intrinsic 14C content in the liquid is extremely low. In the Borexino CTF detector at Gran Sasso, Italy the 14C/12C ratio of 2 × 10-18 has been achieved being the lowest 14C concentration ever measured. In principle, the older the oil or gas source that the liquid scintillator is derived of and the deeper it situates, the smaller the 14C/12C ratio is supposed to be. This, however, is not generally the case, and the ratio is probably determined by the U and Th content of the local environment.

  15. Root activity studies of cashew plants (Anacardium Occidentale L.) using 32P radioisotope

    International Nuclear Information System (INIS)

    In this preliminary study, we are looking at levels 32P and depths of soil injections on uptake by plants using the injection techniques in root activity studies. 32P activities can be detected in the leaves and flower parts of plants two weeks after injection in the soil. Reasonable count rate can be obtained by using lower level of 32P (1.6 mCi/tree) than recommended (5 mCi/tree). 32P counts were higher in younger than older leaves. Flowers had the least count. Differences in injection depths (5 and 15 cm) could not be detected. Differences in count rate were detected due to position of leaves and flowers (upper and lower canopy) in some of the sampling intervals. (author)

  16. Determination of phagocytosis of /sup 32/P-labeled Staphylococcus aureus by bovine polymorphonuclear leukocytes

    Energy Technology Data Exchange (ETDEWEB)

    Dulin, A.M.; Paape, M.J.; Weinland, B.T.

    1984-04-01

    A procedure for the measurement of phagocytosis by bovine polymorphonuclear leukocytes (PMN) of /sup 32/P-labeled Staphylococcus aureus was modified so that a larger number of samples could be compared in a single run, and smaller volumes of sample, PMN, and /sup 32/P-labeled S aureus could be used. Results were highly reproducible, with a coefficient of variation between duplicate determinations of less than or equal to 2%. Lysostaphin was prepared from the supernatant of S staphylolyticus and was compared with a commercially available preparation. Effects of lysostaphin on PMN and influence of incubation media on release of /sup 32/P from /sup 32/P-labeled S aureus by lysostaphin were examined.

  17. Uptake and distribution of 32P in the budded and self-rooted grape varieties

    International Nuclear Information System (INIS)

    In the self-rooted and budded varieties of grape (Vitis vinifera L.), the total P and 32P contents were high in 'Anabee-Shahi', but low in in 'Muscat'. The growing shoots contained more P than old stems and roots in all the varieties. In the budded plants, 'Kali Sahebi' scion budded on 'Anab-e-Shani showed the maximum 32P and total P in the shoots, but 'Muscat' scion budded on 'Anab-e-Shahi' accumulated more P in the roots and very low 32P in the growing shoots. Auto-radiographs of shoots also showed that 'Kali Sahebi' budded on 'Anab-e-Shani' rootstock accumulated more 32P in the shoots. (author)

  18. Temporal distribution of bomb 14C in a forest soil

    International Nuclear Information System (INIS)

    Patterns of 14C enrichment in the superficial plant debris and mineral soil horizons of an established woodland have been monitored at regular intervals during the past 15 years. These data are compared with a model evaluation of carbon turnover based on the recorded changes in atmospheric 14C concentration since AD 1900. Leaf litter and decomposing plant debris are characterized by steady-state turnover values of ca 2 and ca 8 years, respectively. A two-component system of fast (≤20 yr) and slow (ca 350 yr) cycling carbon is indicated for the surface (0-5cm) soil humus; below 10cm, the fast component is rare (14C to the soil carbon pool

  19. Persistence of 14C maneb in lettuce plants an soil

    International Nuclear Information System (INIS)

    Maneb residue is studied on lettuce plant and soil after spraying on greenhouse with 14C maneb. The residues declined with time. After 37 days from the application, 14C maneb residues in water extracts declined to 1,5. 10-2ug/g from 5,8. 10-1ug/g of the zero day sample in lettuce plants and 4,6. 10-3ug/g from 1,73. 10-1ug/g in soil. The 14C internals residues in lettuce and soil increase respectively till 16 days and 24 days, then decrease to 88% and 4,05% after 37 days. ETU was present in lettuce plant after 8 days then decreases with time. Two metabolites were identified by TLC (EU,ETU)

  20. Synthesis of paclitaxel-C3`-{sup 14}C

    Energy Technology Data Exchange (ETDEWEB)

    Walker, D.G.; Standridge, R.T.; Swigor, J.E. [Bristol-Myers-Squibb Co., Syracuse, NY (United States). Pharmaceutical Research Inst.

    1995-12-31

    Reductive cleavage of the C13 side chain of paclitaxel (3) followed by regioselective silylation gave 7-triethylsilybaccatin lll (6). Successive reaction of L-threonine methyl ester hydrochloride (7) with tertbutoxydiphenylchlorosilane, benzaldehyde-C7-{sup 14}C and acetoxyacetyl chloride/triethylamine gave a 92:8 ratio (NMR) of azetidinones in 57% yield from 7. Removal of the chiral auxiliary, and 3-O-triethylsilylation and N-benzoylation provided (3R,4S)-cis-1-benzoyl-3-O-(triethylsilyl)-4-phenylazetidin-2-one-C 4-{sup 14}C (18). Coupling of 18 and 6 followed by deprotection gave 1.12 g of paclitaxel-C3`-{sup 14}C having a specific activity of 16.4 mCi/mmol and a radiochemical purity of 96%. (Author).

  1. Transformation of Straw 14C in Ultisol and Vertisol

    Institute of Scientific and Technical Information of China (English)

    WANGZHIMING; HUANGDONGMAI; 等

    1998-01-01

    Laboratory incubation was conducted to investigate transformation of straw 14C in Ultisol and Vertisol under aerobic conditiol for 112 d at 30℃,Dried and ground 14C-labeled rice and majze straws sere mixed with the soils at the rate of 2.5g kg-1 ,Decomposition of the straw C and native soil C both revealed two stages,being faster during the intial day,and slower thereafter,About 37.33%-48.80% of the straw C and 4.22%-6.83% of the native soil C decomposed by the end of the incubation.The kinds of the straws only slightly influenced the rates of their decomposition in soils,however,some retardation was found in Ultisol at the intial decomposition stage due to its lowr pH.Positvie priming effects were observed in the soils spplied with straw ,and the rate of priming effect ranged from 7.23% to 13.80%.Net losses of native soil C were found under such incubation conditions ,except Ultisol with rice straw.Soil biomass of and 14C decreased gradually with incubation time,and seemed to be consistent with the decomposition patterns of straw C and native soil C.The ratio of biomass 12C to biomass 14C ranged from 1.35 to 3.37 .soil biomass C occupied 1.17%-2.32% of the total soil organic C,and the proportion of biomass 14C to the residual 14C varied from 7.3% to 14.3%.

  2. Causes of an AD 774-775 14C increase

    CERN Document Server

    Melott, Adrian L; 10.1038/nature11695

    2012-01-01

    Atmospheric 14C production is a potential window into the energy of solar proton and other cosmic ray events. It was previously concluded that results from AD 774-775 are orders of magnitude greater than known solar events. We find that the coronal mass ejection energy based on 14C production is much smaller than claimed, but still substantially larger than the maximum historical Carrington Event of 1859. Such an event would cause great damage to modern technology, and in view of recent confirmation of superflares on solar-type stars, this issue merits attention.

  3. AMS of {sup 14}C at low energies

    Energy Technology Data Exchange (ETDEWEB)

    Suter, M.; Huber, R.; Jacob, S. [ETHZ, Zurich (Switzerland); Synal, H.A. [Paul Scherrer Inst. (PSI), Villigen (Switzerland)

    1997-09-01

    At the ETH/PSI AMS facility {sup 14}C test measurements have been performed at low terminal voltages of 0.5 and 1 MV in order to study the feasibility of AMS with very small accelerators. These experiments have demonstrated that interfering molecules ({sup 13}CH and {sup 12}CH{sub 2}) in charge states 1{sup +} and 2{sup +} can be destroyed in an adequate Ar gas stripper. These new results imply the feasibility of a new generation of very small accelerator systems for {sup 14}C. (author) 1 fig., 3 refs.

  4. Synthesis of phenyl(1-/sup 14/C)acetylene and 1,4-diphenyl (1,4-/sup 14/C/sub 2/)butadiyne

    Energy Technology Data Exchange (ETDEWEB)

    Dhawan, S.N.; Kagan, J. (Illinois Univ., Chicago (USA). Dept. of Chemistry)

    1982-03-01

    Phenyl(1-/sup 14/C)acetylene (0.012mCi/mmole) was synthesized in 12.5% yield from (1-/sup 14/C)acetic acid through (1-/sup 14/C)acetophenone, its semicarbazone, and 4-phenyl-(4-/sup 14/C)1,2,3-selenadiazole obtained by selenium dioxide oxidation. Oxidative coupling gave 1,4-diphenyl(1,4-/sup 14/C/sub 2/)butadiyne in 80% yield.

  5. Photosynthetic incorporation of 14C by Stevia rebaudiana

    International Nuclear Information System (INIS)

    The photosynthetic incorporation of 14 by Stevia rebaudiana specimens was investigated. The 14C incorporation, when the isotope was furnished to the plant in form of 14CO2, was rapid. After 24 hours, the radioactivity has been incorporated into a great number of compounds including pigments, terpenes, glucose, cellulose and also stevioside and its derivatives. (M.A.C.)

  6. The synthesis of [14C] C I pigment violet 19

    International Nuclear Information System (INIS)

    For the custom synthesis of radiolabeled compounds in the authors laboratory, aside from spectroscopic examination, their identity and radiochemical purity is routinely corroborated by demonstration of cochromatography with an authentic cold standard. In the synthesis of [14C] red pigment 1 for the Cosmetic Toiletry and Fragrance Association, its insolubility precluded this. The preparation as well as characterization of 1 is described

  7. Fungal bio-degradation of 14C-parathion

    International Nuclear Information System (INIS)

    14'C-parathion (670 Bq) was applied to mineral salt medium (MSM) to examine and evaluate its biodegradation by some fungi. The studied isolates were Alternaria alternate, Fusarium oxysporim and trichoderma viride. The inoculated media were incubated at 30 oC for periods of 2, 4, 6 and 8 days. Ta each interval, mycelia were separated from nutrient solution and extracted for its radioactivity. However, non extractable compounds were liberated by combustion. Quantitative and qualitative analysis were carried out for the radioactive compound in mycelia l extracts and residues as well as the fungal culture filtrate. Balance sheet for total recovered radioactive compounds was concluded 14'C-parathion metabolism was expressed as original compound, polar metabolite, non polar metabolites and non extractable residues and then degradation rate was calculated. araesults indicated that there was continuous penetration for the radioactivity into mycelia tissues and the maximum, accumulation was recorded by Fusarium Oxysporium. The fungi under investigation showed considerable variations regarding their capacity to degrade the radioactive pesticide. Trichoderma viride exhibited the maximum capability to catabolism the the 14C-parathion as it exerted the maximum degradation rate. Fusarium and Alternate alter nata showed less degradation rates for the 14C- pesticide under investigation. (Author)

  8. Reconstructing Ocean Circulation using Coral (triangle)14C Time Series

    Energy Technology Data Exchange (ETDEWEB)

    Kashgarian, M; Guilderson, T P

    2001-02-23

    We utilize monthly {sup 14}C data derived from coral archives in conjunction with ocean circulation models to address two questions: (1) how does the shallow circulation of the tropical Pacific vary on seasonal to decadal time scales and (2) which dynamic processes determine the mean vertical structure of the equatorial Pacific thermocline. Our results directly impact the understanding of global climate events such as the El Nino-Southern Oscillation (ENSO). To study changes in ocean circulation and water mass distribution involved in the genesis and evolution of ENSO and decadal climate variability, it is necessary to have records of climate variables several decades in length. Continuous instrumental records are limited because technology for continuous monitoring of ocean currents (e.g. satellites and moored arrays) has only recently been available, and ships of opportunity archives such as COADS contain large spatial and temporal biases. In addition, temperature and salinity in surface waters are not conservative and thus can not be independently relied upon to trace water masses, reducing the utility of historical observations. Radiocarbon in sea water is a quasi-conservative water mass tracer and is incorporated into coral skeletal material, thus coral {sup 14}C records can be used to reconstruct changes in shallow circulation that would be difficult to characterize using instrumental data. High resolution {Delta}{sup 14}C timeseries such as ours, provide a powerful constraint on the rate of surface ocean mixing and hold great promise to augment one time oceanographic surveys. {Delta}{sup 14}C timeseries such as these, not only provide fundamental information about the shallow circulation of the Pacific, but can also be directly used as a benchmark for the next generation of high resolution ocean models used in prognosticating climate. The measurement of {Delta}{sup 14}C in biological archives such as tree rings and coral growth bands is a direct record of

  9. Fractionation of phosphorus added as a vegetal residue (32 P) and a fertilizer (32 P) between soil, plant and microbial biomass

    International Nuclear Information System (INIS)

    Sugar cane straw and/or P-fertilizer phosphorus-32 labelled were added to a Red Yellow podzolic soil from Goiana-PE. The treated samples were used in a pot experiment, growing sorghum plants for 4 and 6 weeks, and in an incubation experiment with incubation periods of 1, 2, 3, 4 and 6 weeks without plants in order to follow the dynamics of the P added. After each harvest and incubation period the soil were analysed for 31 P and 32 P in the microbial biomass and in sequential extracts with resin (Pi), 0.5 M Na H Co3 (Pi, Po) and 0.1 N NaOH (Pi, Po). The 31 P and 32 P contents of the sorghum in the pot experiment were also determined. (author)

  10. Bioaccumulation factor for 32P measured in bluegill, Lepomis macrochirus, and catfish, Ictalurus punctatus

    International Nuclear Information System (INIS)

    The ratio of the bioaccumulation factors for 32P and phosphorus was determined for edible tissue in two species of freshwater fish by measuring the specific activity (32P activity per milligram phosphorus) in muscle relative to feed. The 32P tracer was added to the feed at a uniform level throughout the study. Feeding was at two levels: ad libitum and at a lower but constant intake per body weight. In the main experiment, bluegill were maintained in a large flow-through tank and sacrificed at approximately weekly intervals for 51 d of 32P accumulation and 28 d of depuration to compare the specific activity with values predicted with a calculational model. In experiments performed in smaller aquaria, the specific activity in bluegill and catfish muscle was compared at two feeding levels and two temperatures. In addition, unfed fish were exposed to 32P in water at a known specific activity to determine the extent of phosphorus uptake directly from water. The pattern of specific activity increase and decrease in fish muscle during the accumulation/depuration experiment was consistent with a one-compartment model, so that specific activity ratios at steady state could be predicted from measurements during relatively brief exposures. On this basis, the ratio of the bioaccumulation factors of 32P and phosphorus in fish feeding ad libitum was 0.081 for bluegill and 0.17 for catfish. Hence, at a mean phosphorus bioaccumulation factor of 70,000, the factors for 32P are 6000 and 12,000, respectively. The ratios were less at lower phosphorus intakes associated with lower feeding rates; moreover, the lesser value for bluegill occurred at a much lower phosphorus intake than by catfish

  11. Acetylcholine increases the breakdown of triphosphoinositide of rabbit iris muscle prelabelled with [32P] phosphate.

    Science.gov (United States)

    Abdel-Latif, A A; Akhtar, R A; Hawthorne, J N

    1977-01-15

    1. Paired iris smooth muscles from rabbits were incubated for 30 min at 37 degrees C in an iso-osmotic salt medium containg glucose, inositol, cytidine and [32P]phosphate. 2. One of the pair was then incubated at 37 degrees C for 10 min in unlabelled medium containing 10mM-2-deoxyglucose and the other was incubated in the presence of acetylcholine plus eserine (0.05mM each). 2-Deoxyglucose, which was included in the incubation medium to minimize the biosynthesis of triphosphoinositide from ATP and diphosphoinositide, decreased the amount of labelled ATP by 71% and inhibited further 32P incorporation from ATP into triphosphoinositide by almost 30%. 3. Acetylcholine (0.05mM) increased significantly the loss of 32P from triphosphoinositide (the 'triphosphoinositide effect') in 32P-labelled iris muscle. This effect was measured both chemically and radiochemically. It was also observed when 32Pi was replaced by myo-[3H]inositol in the incubation medium. 4. The triphosphoinositide effect was blocked by atropine but not by D-tubocurarine. Further, muscarinic but not nicotinic agonists were found to provoke this effect. 5. Acetylcholine decreased by 28% the 32P incorporation into triphosphoinositide, presumably by stimulating its breakdown. This decrement in triphosphoinositide was blocked by atropine, but not by D-tubocurarine. 6. The triphosphoinositide effect was accompanied by a significant increase in 32P labelling, but not tissue concentration, of phosphatidylinositol and phosphatidic acid. The possible relationship between the loss of 32P label from triphosphoinositide in response to acetylcholine and the concomitant increase in that of phosphatidylinositol and phosphatidic acid is discussed. 7. The presence of triphosphoinositide phosphomonoesterase, the enzyme that might be stimulated in the iris smooth muscle by the neurotransmitter, was demonstrated, and, under our methods of homogenization and assay, more than 80% of its activity was localized in the

  12. Construction of expression vector containing glnA gene and detection of NPT II activity in the transgenic rice calli using 32P-labelled compound

    International Nuclear Information System (INIS)

    The glnA gene encoding glutamine synthetase (GS) was amplified from Azospirillum brasilense Sp7 by PCR technique. the amplified 1.4 kb DNA fragment was cloned at the EcoRV site of Bluescript-SK. Both sequencing and restriction digestion data showed that the 1.4 kb DNA fragment flanked with BamHI site at each end was really the glnA gene of A. brasilense Sp7. The glnA gene was ligated with Bg1 II site of pCo24. As a result, an expression vector pGSC35 with CaMV35S promoter was obtained. Using colony in situ hybridization with α-32P-dATP labelled probes to screen the positive clones, another glnA gene expression vector pAGNB92 with rice actin 1 promoter was constructed after three rounds of ligation and transformation. Protoplasts isolated from rice cell suspension line cv. T986 were transformed with glnA expression vectors pGSC35 and pAGNB92 containing neomycin phosphotransferase II (NPTII) gene by using PEG fusion and electroporation. Transformed microcalli were selected on media containing G418 disulfate salt. NPT II activity was detected in 37% of G418 resistant calli by using dot blot hybridization with γ-32P-ATP and kanamycin as substrate

  13. Autoradiographic visualization in comparison with the incorporation of 35S-methionine by various tissue protein

    International Nuclear Information System (INIS)

    The purpose of the present study was to observe the incorporation level of 35S-methionine by various tissue protein in organism. By the use of the macro- and micro-autoradiographic technique, the incorporation of 35S-methionine by the tissues has been utilized as an index of tissue protein synthesis. Further experiments showed that 35S-methionine was dominantly incorporated in the liver, kidney and spleen. It indicated that a strong protein metabolism produced in these tissues. In spite of the important physiological function of the heart, lung and skeletal muscle, the protein metabolism in those tissues was in a low level

  14. Dating of groundwater with tritium and 14C

    International Nuclear Information System (INIS)

    Shallow groundwater can be dated with some accuracy on the basis of its bomb tritium content if the unsaturated soil cover and the aquifer itself is sufficiently homogeneous. A few examples from the Rhine valley are presented. The decrease in tritium level from the water table to a few metres below is nearly two orders of magnitude. Agreement between the measured or estimated variation of bomb tritium in rain during the past decade and the tritium found in shallow groundwater can be obtained if one takes into account that (a) practically no summer rain reaches the water table, and (b) water is mixed by diffusion. Both effects can also be observed in the soil moisture of the unsaturated soil above the water table. Carbon-14 increase in groundwater due to bombs is delayed compared to tritium, the reasons being delay in the biological system and exchange with the carbonate in the soil. Nevertheless lysimeters show a marked increase of 14C, which depends on the plant cover, being high in a plant-covered lysimeter and low in a bare one. A simple model is presented, which allows the evaluation of the influence of exchange on the 14C age obtained. It turns out that the deviation from the true age depends on the ratio of the carbonate content in the aquifer material to the carbonate content of the water, on the specific contact surface or the grain size but not on the groundwater velocity. On the basis of this model the experimental finding that 14C ages are usually in agreement with other age estimates despite the loss by exchange is plausible owing to the fact that only material of sufficiently coarse grain size can make up a reasonable aquifer. Assuming only exchange with a monomolecular surface layer of the carbonate grains one finds that the 14C age is likely to differ by not more than a factor of two in the most unfavourable case. Under natural conditions (steady state of cosmic-ray-produced 14C) the 14C content of shallow groundwater is hardly influenced at all by

  15. Insulin and thyroxine effect on 32P incorporation in the phospholipids of chicken intestinal mucosa

    International Nuclear Information System (INIS)

    Trials were conducted with 56-day-old broiler chickens. The effect was followed up of insulin and alloxan as well as of L-thyroxine and 6-methylthiouracil on 32P incorporation in phospholipids of the duodenal mucosa. A segment of the duodenum was isolated and Na2H32PO4 was introduced therein. The lipids were extracted from duodenal mucosa and the individual phospholipids were separated by means of thin layer chromatography on sillica gel-G. Radioactivity was determined of individual phospholipid fractions. Blood glucose level was studied in insulin and alloxan-treated chickens. The inference was drawn that insulin significantly enhances 32P incorporation in the phospholipids in broiler chicken duodenal mucosa. The drop in blood glucose in insulin-treated chickens is inversely proportional to 32 P inclusion in individual phospholipids of duodenal mucosa. L-thyroxine exerts positive effect in chickens concerning 32P incorporation in lecithin and lysolecithin, this effect being negative with respect to sphingomyelin, cephalin and cardiolipin. Thyroid gland inhibition by 6-methylthiouracil induces negligible decline in 32P inclusion. (author)

  16. Preparation and evaluation of various 32P sources for intravascular brachytherapy

    International Nuclear Information System (INIS)

    A relatively high per cent of restenoses, being a long-term complication of percutaneous transluminal coronary angioplasty (PTCA), can be significantly reduced by short-range ionizing radiation applied locally, immediately after PTCA. In search for dosimetrically favourable and easy to handle radiation sources for this purpose, we tried a pure β- emitter 32P (t1/2=14.3 days). Ways of preparation of 32 P sources were the following: (1) Neutron activation of 31P layers implanted into metallic surfaces by ionic methods; (2) Conversion coating of metallic surfaces in aqueous solutions containing 32PO43- ions; (3) Direct application of Na2H32 PO4 solutions in the angioplasty balloon. It was shown that: (1) 32 P sources obtained by 31 P ion implantation followed by neutron activation can be useful, but only if activation of the support material by thermal neutrons is negligible; (2) Phosphate layers on stainless steel surface exhibit rather poor adhesion. Similar layers on titanium require further studies; (3) Liquid 32 P sources ensure very good radial dose distribution but only utmost care in filling the balloon can give a reliable activity-dose dependence. Dosimetry of liquid sources, performed in a PMMA phantom by thermoluminescence method showed that 32 P sources of radioactive concentration of 200 MBq/cm3 can deposit therapeutic dose during about 12 min of exposition. TL detectors manufactured for this purpose in our laboratory show very good spatial resolution and can be recommended for similar studies. (author)

  17. Changes of decay rates of radioactive 111In and 32P induced by mechanic motion

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    The changes of decay rates of radionuclide 111In(electron capture) and 32P(β decay) induced by exter-nal mechanic motion are studied. The results indicate that,in the external circular rotation in clockwise and anticlockwise centrifuge on Northern Hemisphere(radius 8 cm,2000 r/min) ,the half life of 111In compared with the referred(2.83 d) is decreased at 2.83% and increased at 1.77%,respectively;the half life of 32P compared with the referred(14.29 d) is decreased at 3.78% and increased at 1.75%,respec-tively. When the clockwise and anticlockwise rotations increase to 4000 r/min,the half life of 111In is decreased at 11.31% and increased at 6.36%,respectively;the half life of 32P is decreased at 10.08% and increased at 4.34%,respectively. When the circular rotation is removed,the decay rates of 111In and 32P return back to the referred,respectively. It is found that the external circular rotations in clockwise and anticlockwise centrifuge selectively increased and decreased the decay rates of 111In and 32P,respec-tively,and the effects are strongly dependent on the strength of circular rotation. It is suggested that these effects may be caused by the chiral interaction.

  18. Decay of 226Ra by 14C emission

    International Nuclear Information System (INIS)

    Since the pioneering experiment by Rose and Jones in 1984 demonstrating 14C decay of 223Ra, spontaneous emission of clusters heavier than α particles but lighter than fission products could be found in several cases to be a rare decay mode of heavy nuclei. This new kind of radioactivity has branching ratios relative to α decay well below 10-9. For energetical reasons the emitted fragments are even-even and the daughter nucleus lies close to the doubly magic 208Pb. Polycarbonate track-recording foils which are sensitive to energetic carbon nuclei but not to α particles are very well suited detectors for the study of 14C emission radioactivity. The tracks are made visible under a microscope by etching techniques. Observation of spontaneous emission of 14C from 226Ra claimed by Hourani et al. and Barwick et al. has been confirmed. Since thick sources of 226Ra were used in these experiments the experimental definitions of decay energy and mass were not very accurate. The experiment described in the thesis measured for the first time charge and energy of the emitted fragments by using thin 226Ra sources and polycarbonate track-recording films. The decay mode could thus be identified unambiguously. The track detector was calibrated with tandem-accelerated 14C and 16O ions and tested by observing the now well established 14C emission from 223Ra; for this decay mode a branching ratio of (5,0 ± 1,0).10-10 relative to α decay was found in agreement with values from the literature. In the case of 226Ra the result for 14C/α ratio is (2,3 ± 1,2).10-11. The order of magnitude of the branching ratios can be reproduced by theoretical models. Estimates of partial half-lifes of Ra and other heavy isotopes for rare decay modes are discussed in the theoretical section of the thesis. 100 refs., 3 tabs., 30 figs. (Author)

  19. Design and construction of a prototype for the obtention of {sup 32}P; Diseno y construccion de un prototipo para la obtencion de {sup 32}P

    Energy Technology Data Exchange (ETDEWEB)

    Duarte A, C

    2003-07-01

    The {sup 32} P are a pure emitting radioisotope of maximum energy of 1.71 MeV with half life of 14.28 days that he has applications in the industry, in agriculture, in medicine, in biology and in ecology (6,11,12,13,17,21,22,23,24,25,26,27,28,29,30,31,32 33).The {sup 32} P can be used in the industry like radiotracer in the investigation of some operations and processes and as element of measurement of some industrial meters. In agriculture is used as radiotracer (29) in the investigation of diverse biological processes that have to do with the production of diverse nutritious products. In medicine has uses but very therapeutic mainly in the treatment of some become cancerous (28, 31, 25, 27) in the diagnosis of blood disorders (24) and like part of materials of production of aortic prosthesis (6). The {sup 32} P are also used in the molecular investigation in biology and in genetics (33), and in studies of ecosystems (32) and of DNA (22). One can obtain the {sup 32} P by means of diverse nuclear reactions depending on the material used as matter it prevails, since it doesn't exist in the nature. But anyone in the ways of obtaining it it should imply a process of radiochemical separation that involves so many steps like they are required, depending on the material used as matter prevails, of the purity with which he wants himself to obtain and of the resources that it has available. The objective of this work was design, to build and to prove a prototype to obtain the {sup 32} P to leave of the irradiation of S {alpha} with fast neutrons at experimental level, which implies also to design a process that contemplates diverse stages and procedures for each one of them. The process was outlined in five stages: matter purification prevails, preparation of irradiation capsules, irradiation of irradiation capsules, transport and opening capsules of irradiation and radiochemical separation. In the last stage it was where uses the prototype of radiochemical separation

  20. Studies on the shelf-life of L-35S methionine

    International Nuclear Information System (INIS)

    A systematic study conducted on the shelf -life of L-35S- methionine, an important radiotracer used in protein synthesis experiments is reported. Aliquots of 35S-methionine from bulk sample prepared by us were kept under chosen conditions of storage and were analysed by paper chromatography coupled with autoradiography. The radiochemical purity (RCP) of 35S-methionine at various time interval spanning over a period of about one half-life of 35S radioisotope (87.4 days) was determined. It was observed that the RCP came down only to about 89% from the original value of 96% at the end of the period of study under the chosen conditions. (author)

  1. A critical review of atmospheric 14 C activities

    Energy Technology Data Exchange (ETDEWEB)

    Krajcar Bronic, I.; Horvatincic, N.; Baresic, J.; Obelic, B. [Rudjer Boskovic Institute, Zagreb (Croatia); Vreca, P. [Jozef Stefan Institute, Ljubljana, (Slovenia)

    2006-07-01

    14 C activity of atmospheric CO{sub 2} has been measured at the Rudjer Boskovi Institute as a part of environmental monitoring in order to determine possible differences between clean-air sites, industrialized city and sites in the vicinity of nuclear power plant. Samples of Cfrom the atmosphere have been collected by absorption of CO{sub 2} on the saturated carbonate-free NaOH solution for a period of 1 month under stationary conditions. The obtained Na{sub 2} CO{sub 3} has been dissolved in HCl and the produced CO{sub 2} used for CH{sub 4} preparation by catalytic reaction with H{sub 2} at 450 degrees Celsius. A gas proportional counter filled with CH{sub 4} has been used for 14 C activity measurement. The method of collection of CO{sub 2} does not require any power source and can be therefore used for sampling at the remote sites, such as mountains or forests. However,due to the lack of mixing of the Na OH solution, the absorption process is limited on the surface of the solution, and there exists the possibility of fractionation of carbon isotopes due to different reaction rate constants of 12 C and 13 C. A continuous record of atmospheric 14 CO{sub 2} activity exists for the city of Zagreb (1986 to 2005), while shorter records (1-2 years) exist for several other sites of various characteristics: two clean-air sites (Mt. Medvednica, altitude about 1000 m a.s.l., for period 1995 to 1996, and the Plitvice National Park for period 2003 to 2005), and a site close to the Nuclear Power Plant Krsko (1984 to 1986).Within the bilateral Croatian-Slovene project we have recently measured also the stable isotope composition ({delta}13 C) of Na{sub 2}CO{sub 3} collected at two different sampling sites in order to determine seasonal fluctuations in both 14 C and 13 C isotope composition. Unexpectedly low {delta}13 C values have been obtained about (-25{+-}2)0/00 instead of expected (-7{+-}1)0/00. Such low values have been attributed to the carbon isotope fractionation during

  2. Fate of 14C-monocrotophos in lactating goats

    International Nuclear Information System (INIS)

    14C-monocrotophos was fed daily to two groups of lactating goats for five days at 5 and 10 mg per goat per day. The radioactivity in urine and faeces accounted for 50% and 7%, respectively, 24 hours after the first dose. About 25% of the radiocarbon was found in various organs. About 1-2% of the administered radiocarbon was secreted in milk. It was concluded that monocrotophos was rapidly eliminated through urine and faeces of teddy goats. 14C-residues in milk and urine were tentatively identified as monocrotophos, dimethylphosphate and N-desmethyl monocrotophos. The erythrocyte cholinesterase activity was reduced to 50% 24 hours after treatment, but no toxic symptoms were observed. (author)

  3. May 14C be used to date contemporary art?

    Science.gov (United States)

    Fedi, M. E.; Caforio, L.; Mandò, P. A.; Petrucci, F.; Taccetti, F.

    2013-01-01

    The use of radiocarbon in forensics is by now widespread, thanks to the so-called bomb peak, which makes it possible to perform high-precision dating. Since 1955, 14C concentration in the atmosphere had strongly increased due to nuclear explosions, reaching its maximum value in 1963-1965. After the Nuclear Test Ban Treaty, 14C started to decrease as a consequence of the exchanges between atmosphere and the other natural carbon reservoirs. Nowadays, it is still slightly above the pre-bomb value. The work presented in this paper is based on the idea of exploiting the bomb peak to “precisely” date works of contemporary art, with the aim at identifying possible fakes. We analysed two kinds of materials from the 20th century: newspapers and painting canvases. Newspaper samples were taken because they might in principle be considered to represent dated samples (considering the date on the issues). Our data (28 samples) show a trend similar to atmospheric data in the literature, although with some differences; the paper peak is flatter and shifted towards more recent years (about five years) with respect to the atmospheric data. This can be explained by taking paper manufacturing processes into account. As to the canvas samples, the measured 14C concentrations were generally reasonably consistent with the expected concentrations (based on the year on the paintings). However, this does not indicate that the interpretation of the results is simpler and more straightforward. Obviously, we only measure the 14C concentration of the fibre used for the canvas, which does not necessarily measure the date the painting was manufactured. In this paper, sample preparation and experimental results will be discussed, in order to show the potential as well as the limitations of radiocarbon to date contemporary art.

  4. TMEM14C is required for erythroid mitochondrial heme metabolism

    OpenAIRE

    Yien, Yvette Yee; Robledo, Raymond F.; Schultz, Iman J.; Takahashi-Makise, Naoko; Gwynn, Babette; Bauer, Daniel Evan; Dass, Abhishek; Yi, Gloria; Li, Liangtao; Hildick-Smith, Gordon J.; Cooney, Jeffrey D.; Pierce, Eric Adam; Mohler, Kyla; Dailey, Tamara A.; Miyata, Non

    2014-01-01

    The transport and intracellular trafficking of heme biosynthesis intermediates are crucial for hemoglobin production, which is a critical process in developing red cells. Here, we profiled gene expression in terminally differentiating murine fetal liver-derived erythroid cells to identify regulators of heme metabolism. We determined that TMEM14C, an inner mitochondrial membrane protein that is enriched in vertebrate hematopoietic tissues, is essential for erythropoiesis and heme synthesis in ...

  5. Residues of 14C-paclobutrazol in mangoes

    International Nuclear Information System (INIS)

    Paclobutrazol (PBZ) is a growth regulator used in agricultural systems whose purpose is the control of vegetative growth, stimulating the reproductive capacity of plants. This growth regulator remains active in soil for a long time and its half-life varies with the type of soil and climatic conditions, can severely affect the development of crops. This work aimed to study the residues / metabolites of 14C-PBZ in mango pulp Tommy Atkins. The tests were performed with mangoes grown in pots stainless steel and application of 14C-PBZ was performed by the soil projection of the crown, and the mangoes tested in two periods, one year and two years after application. To evaluate the levels of residues of 14C-PBZ was realize the burning of 200 mg of pulp on biological oxidized and detached 14CO2 was detected by liquid scintillation spectrophotometer. The results were 1.65 % of residue of PBZ on fruit collected after two years of application and 4.30 % of residue of PBZ collected on fruit after a year of application and also can see that the product remained in the soil for more than one year, is translocated to the plant and reach the edible part, the pulp fruit. The identification of residual 14C- PBZ/metabolites by thin-layer chromatography did not reveal any pattern of PBZ / metabolites due to the low activity detected in the samples. Therefore, another procedure was performed for extraction and then analyzed by high performance liquid chromatography (HPLC) for detection of metabolites in the PBZ of mango pulp. (author)

  6. 14C content in aerosols in Mexico City

    Science.gov (United States)

    Gómez, V.; Solís, C.; Chávez, E.; Andrade, E.; Ortiz, M. E.; Huerta, A.; Aragón, J.; Rodríguez-Ceja, M.; Martínez, M. A.; Ortiz, E.

    2016-03-01

    14C-AMS of total carbon was determined in aerosols (PM10 fraction), collected in Mexico City during two weeks from 21 November to 3 December 2012. Other tracers such as total carbon (TC), organic carbon (OC), elemental carbon (EC) and trace element contents were also determined. F14C values varied from 0.39 to 0.48 with an average of 0.43. These values are slightly lower than those previously obtained for PM2.5 in 2003 and 2006 and reflect a high contribution of fossil CO2 to the carbonaceous matter in aerosols from Mexico City. In contrast, from 2006 to 2012 PM10 increased; EC, Ca, Ti and Fe concentrations remained constant, while OC, TC and K concentrations decreased. The use of potassium as an indicator of biomass burning showed that this source was negligible during this campaign. Combined analytical approaches allowed us to distinguish temporal variations of anthropogenic and natural inputs to the F14C.

  7. Biodegradation of 14 C-atrazine under outdoor conditions

    International Nuclear Information System (INIS)

    Uniformly 14 C-ring labeled atrazine (5 L/ha) was applied to a Typical Hapludox Brazilian Soil sample which was incubated under outdoor conditions. Sample of 200 g (dry weight base) of fresh soil were distributed in Erlenmeyer flasks and the moisture was adjusted for 2/3 rds of the soil field capacity. The flasks were then buried in the Lysimeter Station when they were incubated. The experiment started jointly with a corn planting. The 14 C O2 was analyzed every 15 day, during a period of 150 days. The desorbed, extracted and bound residues were analyzed. The extracted soil was fractionated and the residues in the humin, fulvic and humic acids were determined. At the end of the incubation period (150 days), the 14 CO2 evolved reached up to 36% of the total applied activity, the bound residues were detected in about the same (34%) during the inoculation period, and were distributed in the fractions of fulvic acids (29,91%), humic acids (6,83%) and humin (63,26%). The metabolites formed in the desorbed residues and in the extracted residues were determined using thin layer chromatography with 14 C-detector. After 150 days incubation, desorbed soil residues were identified as atrazine (52,72%), hydroxiatrazine (44%) and desisopropilatrazine (3,28%). The extractable residues contained atrazine (79,29%), hydroxiatrazine (16,22%), desisopropilatrazine (2,25%) and desetylatrazine (2,24%). (author)

  8. The use of 32P and 15N to estimate fertilizer efficiency in oil palm

    International Nuclear Information System (INIS)

    Improving efficiency of use of fertilizers has attracted a great deal of interest on oil-palm estates because of increasing input costs. It is assumed that higher efficiency of use of fertilizers for estate crops, including oil palm, would result in significant savings and less environmental pollution. One way to enhance efficiency of use of fertilizers by oil palm is to apply them where the most active roots are located. Previous work has indicated the possibility of determining the most active roots of tea and chinchona by using 32P. In this experiment, 32P was again used, to determine the locations of the most active roots of oil palm trees

  9. Uptake of (2-/sup 14/C)abscisic acid and distribution of /sup 14/C in apple embryos

    Energy Technology Data Exchange (ETDEWEB)

    Barthe, P.; Bulard, C.

    1981-01-01

    Pyrus malus L. var. Golden delicious embryos were incubated with (+-)-(2-/sup 14/C) abscisic acid (ABA). After incubations of various durations, the radioactivity was measured in whole embryos, cotyledons, and embryonic axes. With either 48-h or 16-d incubation periods, the uptake of (/sup 14/C) ABA depended upon the mode of culture used. The lowest values corresponded to the absorption by the embryonic axis, the highest to the absorption by the distal parts of the two cotyledons. The cotyledons accumulated the main part of the radioactivity under all conditions. Dormant and almost completely after-ripened embryos cultivated for 4 d showed no significant differences in the radioactivity uptake for identical modes of culture. There was a linear relationship between exogenous ABA concentrations (0.5 to 3.10/sup -5/ M) and ABA uptake for embryos cultivated for 4 d with the distal parts of the cotyledons immersed in the medium.

  10. Amount and identity of (/sup 14/C) residues in bluegills (Lepomis macrochirus) exposed to (/sup 14/C)triclopyr

    Energy Technology Data Exchange (ETDEWEB)

    Lickly, T.D.; Murphy, P.G.

    1987-01-01

    The level and identity of (/sup 14/C) residues in bluegills (Lepomis macrochirus) exposed to 2.5 mg/L (/sup 14/C) triclopyr (3,5,6-trichloro-2-pyridinyloxyacetic acid) have been determined. The highest level of radioactivity observed in the flesh of a fish at any time point (0.13 mg/kg, calculated as equivalent mg triclopyr/kg fish) was less than 5% of the fish exposure level of 2.5 mg/L, while the maximum level in the remainder (head, skin, and viscera) was about 95% (2.33 mg/kg) of the fish exposure level, indicating no concentrating effect. The principal components observed in the fish tissues were triclopyr, 3,5,6-trichloro-2-pyridinol, 2-methoxy-3,5,6-trichloropyridine and a conjugate. These components accounted for greater than 75% of all the residues observed.

  11. Amount and identity of [14C] residues in bluegills (Lepomis macrochirus) exposed to [14C]triclopyr

    International Nuclear Information System (INIS)

    The level and identity of [14C] residues in bluegills (Lepomis macrochirus) exposed to 2.5 mg/L [14C] triclopyr (3,5,6-trichloro-2-pyridinyloxyacetic acid) have been determined. The highest level of radioactivity observed in the flesh of a fish at any time point (0.13 mg/kg, calculated as equivalent mg triclopyr/kg fish) was less than 5% of the fish exposure level of 2.5 mg/L, while the maximum level in the remainder (head, skin, and viscera) was about 95% (2.33 mg/kg) of the fish exposure level, indicating no concentrating effect. The principal components observed in the fish tissues were triclopyr, 3,5,6-trichloro-2-pyridinol, 2-methoxy-3,5,6-trichloropyridine and a conjugate. These components accounted for greater than 75% of all the residues observed

  12. 17 CFR 240.14c-3 - Annual report to be furnished security holders.

    Science.gov (United States)

    2010-04-01

    ... security holders. 240.14c-3 Section 240.14c-3 Commodity and Securities Exchanges SECURITIES AND EXCHANGE... Section 14(c) § 240.14c-3 Annual report to be furnished security holders. (a) If the information statement... such meeting, of security holders at which directors of the registrant, other than an...

  13. Lack of tissue renewal in human adult Achilles tendon is revealed by nuclear bomb (14)C

    DEFF Research Database (Denmark)

    Heinemeier, Katja Maria; Schjerling, Peter; Heinemeier, Jan;

    2013-01-01

    the 14C bomb-pulse method. This method takes advantage of the dramatic increase in atmospheric levels of 14C, produced by nuclear bomb tests in 1955-1963, which is reflected in all living organisms. Levels of 14C were measured in 28 forensic samples of Achilles tendon core and 4 skeletal muscle samples...... is revealed by nuclear bomb 14C....

  14. High-performance liquid chromatography for analysis of 32P-Postlabeled DNA adducts

    OpenAIRE

    Zeisig, Magnus

    1996-01-01

    High-Performance Liquid Chromatography for Analysis of 32P-Postlabeled DNA Adducts Magnus Zeisig Center for Nutrition and Toxicology, Department of Bioscience at Novum, Karolinska Institutet, Novum, S-141 57 Huddinge, SwedenThe formation of DNA adducts, i.e. the covalent binding of chemicals and chemical groups to DNA,isbelieved to be an important step in chemical carciwg...

  15. Uptake of 3HHO and 32P by roots of wheat and rape

    International Nuclear Information System (INIS)

    Direct measurements were made of 3HHO and 32P taken up from labelled soil by roots of wheat (Triticum aestivum L.) and rape (Brassica campestris L.). Single roots were encased in labelled soil for 3 days, and the amount of 3HHO and 32P retained in the shoots was determined. Plants were grown to five stages of maturity in growth boxes under controlled conditions. Roots were labelled at up to four depths (to 90 cm) depending on the rooting depth at each stage of maturity. Uptake of 3HHP per unit length of root increased as the plant age increased, while uptake of 32P decreased to below detection levels by 45 days after germination. Larger amounts of both nutrients were translocated to and retained in the shoots from surface roots than from roots located deeper in the soil although the soil was uniform in temperature, bulk density, and composition through the growth boxes. Wheat roots were more efficient than rape roots in absorbing 3HHO; however, rape roots took up larger amounts of 32P per unit length of root. Neither native nor added P located more than 30 cm deep is of much importance to these annual crops, since uptake is minimal and the main demand for this nutrient occurs at early growth stages when the root system is restricted to the surface layers

  16. Labeling of specific proteins in rat ovarian plasma membranes with [γ-32P]GTP

    International Nuclear Information System (INIS)

    The authors report evidence that [γ-32P]GTP preferentially labels two proteins in rat ovary and parotid membranes that differ structurally from the proteins that are substrates for ADP-ribosylation by cholera toxin and which are thought to be involved in the regulation of adenylate cyclase by GTP. (Auth.)

  17. Rose Atoll Site 32P 2/22/2012 36-37M

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — Onemetersquare 1 meter x 1 meter benthic substrate at Rose Atoll, site 32P 14 32.361S, 168 09.430W, between 36 and 37 meters along a permanent transect.

  18. /sup 32/P and acute leukemia: development of leukemia in a patient with hemoglobin Yakima

    Energy Technology Data Exchange (ETDEWEB)

    Bagby, G.C. Jr.; Richert-Boe, K.; Koler, R.D.

    1978-08-01

    In 1954 a then 31-yr-old male was found to have erythrocytosis. Over the ensuing decade he received 72 mCi /sup 32/P. In 1964 his daughters were found to have erythrocytosis. Further investigation led to the discovery of hemoglobin Yakima, a variant with high oxygen affinity. He received no further therapy and was well until 1975, when he developed the preleukemic syndrome. Within 12 mo he developed acute nonlymphocytic leukemia accompanied by fetal erythropoiesis. Because the initial discovery of this type of hemoglobinopathy came 27 yr after the introduction of /sup 32/P for use in the treatment of polycythemia vera, and because there are now known to be more than 39 different high-oxygen-affinity hemoglobins, we anticipate that more patients such as ours have been exposed to /sup 32/P. The exposed population should be closely followed, since this will likely permit assessment of the risk of /sup 32/P-induced leukemia in a nonneoplastic condition.

  19. Rose Atoll Site 32P 8/2/2004 11-12M

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — One-meter-square (1 meter x 1 meter) benthic substrate at Rose Atoll, site 32P (14 32.361S, 168 09.430W), between 11 and 12 meters along a permanent transect.

  20. Rose Atoll Site 32P 2/22/2012 45-46M

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — Onemetersquare 1 meter x 1 meter benthic substrate at Rose Atoll, site 32P 14 32.361S, 168 09.430W, between 45 and 46 meters along a permanent transect.

  1. Treatment of verruca of hands and feet with 32P application therapy and laser

    International Nuclear Information System (INIS)

    To study and compare the clinical curative effect of extremity verruca with 32P and laser as well as their application values, 229 patients with extremity verruca were chosen by random from outpatient. Out of them, 83 patients were male and 146 were female, with the average age of 34.6 ± 19.5 (x-bar ± s) years. They were randomly divided into two groups: for the laser treatment group consisting of 127 individuals, the wart bodies were eliminated by CO2 laser under local anaesthetization, if there were a lot of locus, the wart bodies were treated in turn. 102 individuals were treated with 32P application therapy. The liquid containing radionuclide 32P was dropped on filter papers, dried and then fixed on the corresponding focus surface for application therapy, applying 4-8 hours continuously (the absorbed dose at the lesion surface reaching 984-1968 cGy) each time and once a week until the lesion recovered. The clinical reaction and curative effect were observed. The clinical effective rate, cure rate, recurrence rate, side effective rate occurrence rate and complication occurrence rate for the laser treatment group are 100%, 55.9%, 44.1%, 17.3% and 25.2%, respectively while they are 100%, 91.2%, 5.9%, 19.6% and 7.8% respectively for the group of 32P application therapy. It is concluded that the treatment of extremity verruca with 32P application therapy is a simple and effective method with features such as safety, little pain, notable curative effect, lower recurrence rate, less side effect and complication. (authors)

  2. Human folate metabolism using 14C-accelerator mass spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Clifford, A. J. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Arjomand, A. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Duecker, S. R. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Johnson, H. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Schneider, P. D. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Zulim, R. A. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Bucholz, B. A. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Vogel, J. S. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

    1999-03-25

    Folate is a water soluble vitamin required for optimal health, growth and development. It occurs naturally in various states of oxidation of the pteridine ring and with varying lengths to its glutamate chain. Folates function as one-carbon donors through methyl transferase catalyzed reactions. Low-folate diets, especially by those with suboptimal methyltransferase activity, are associated with increased risk of neural tube birth defects in children, hyperhomocysteinemic heart disease, and cancer in adults. Rapidly dividing (neoplastic) cells have a high folate need for DNA synthesis. Chemical analogs of folate (antifolates) that interfere with folate metabolism are used as therapeutic agents in cancer treatment. Although much is known about folate chemistry, metabolism of this vitamin in vivo in humans is not well understood. Since folate levels in blood and tissues are very low and methods to measure them are inadequate, the few previous studies that have examined folate metabolism used large doses of radiolabeled folic acid in patients with Hodgkin's disease and cancer (Butterworth et al. 1969, Krumdieck et al. 1978). A subsequent protocol using deuterated folic acid was also insufficiently sensitive to trace a physiologic folate dose (Stites et al. 1997). Accelerator mass spectrometry (AMS) is an emerging bioanalytical tool that overcomes the limitations of traditional mass spectrometry and of decay counting of long lived radioisotopes (Vogel et al. 1995). AMS can detect attomolar concentrations of 14 C in milligram-sized samples enabling in vivo radiotracer studies in healthy humans. We used AMS to study the metabolism of a physiologic 80 nmol oral dose of 14 C-folic acid (1/6 US RDA) by measuring the 14 C-folate levels in serial plasma, urine and feces samples taken over a 150-day period after dosing a healthy adult volunteer.

  3. Effect of anticonvulsant drugs on (35S)t-butylbicyclophosphorothionate binding in vitro and ex vivo

    International Nuclear Information System (INIS)

    Using several concentrations of eight anticonvulsant drugs in clinical use (carbamazepine, clonazepam, phenytoin, phenobarbital, ethosuximide, primidone, sodium valproate, and D,L-γ-vinyl GABA), we studied their abilities in vitro to displace (35S)t-butylbicyclophosphorothionate (35S-TBPS) from its binding site in a homogenate of rat brain. Thereafter ethosuximide (150 mg/kg), phenobarbital (30 mg/kg), clonazepam (0.3 mg/kg), or phenytoin (100 mg/kg) was injected intraperitoneally into rats for 16-20 days; and the effect of drug administration on 35S-TBPS binding was studied in the cortex and hippocampus ex vivo. Phenobarbital (100 μM, P35S-TBPS binding in vitro by 10-16%. After drug administration of phenobarbital (concentration in plasma 168 μM), the number of binding sites decreased and the binding affinity (p35S-TBPS binding in vitro at the concentration analogous to therapeutic plasma levels or ex vivo at the dose used. These results suggest that the use of phenobarbital may modulate the TBPS binding site, but the role of the present findings in the anticonvulsant action of phenobarbital needs to be further studied. (author)

  4. 14C-coumaphos residues in Egyptian lactating goats

    International Nuclear Information System (INIS)

    14C-coumaphos was applied dermally to two lactating goats, with 2 weeks interval. One goat was sacrificed 24 hours after the second application, and the second animal after a withdrawal period of two weeks. The results showed that coumaphos has a slow penetration rate when dermally applied to lactating goats. Milk residues were 0.20-0.25 ppm following appication, declining gradually to 0.03-0.06 ppm after 2 weeks. The liver and kidney were found to contain considerable amounts of coumaphos residues in comparison with other organs and milk after the withdrawal period. (author)

  5. Studies on absorption, conversion of sulfate by rape seedling and accumulation of glucosinolate in rape seed by using 35S

    International Nuclear Information System (INIS)

    The seedlings grown in sandy culture absorbed 35SO42- from cultural solution rapidly and the 35S was incorperated into glucosinolates, amino acids and proteins. Percentage of glucosinolates-35S in extractable 35S with 70% methanol declined and those of amino acid-35S rose regularly with time after labelling. The relative content of 35S incorperated into bound constituents as well as extractable components was constant after 5 days of labelling. From two weeks after flowering, the relative content of GS-35S in pods and seeds increased linearly with time until eight weeks after flowering when all 35S extracted with 70% methanol in seeds were in form of glucosinolate. The amount of 35S-GS per pod increased linearly from the first week to the eighth week after flowering. It seems that the accumulation of GS in seeds is related to the accumulation of dry matter in seeds

  6. A high resolution method for 14C analysis of a coral from South China Sea: Implication for "AD 775" 14C event

    Science.gov (United States)

    Ding, Ping; Shen, Chengde; Yi, Weixi; Wang, Ning; Ding, Xingfang; Liu, Kexin; Fu, Dongpo; Liu, Weiguo; Liu, Yi

    2015-10-01

    A pre-heating method that improves the background and precision of 14C dating significantly was applied for fossil coral dating with high resolution in our lab in Guangzhou Institute of Geochemistry, Chinese Academy of Sciences (GIGCAS). The reaction tube is heated under 300 °C in a vacuum line before it is used for graphitization. The method can reduce the contamination absorbed in TiH2, Zn and Fe power placed in the graphitization tube. With the pre-heating and average drilling method, bi-weekly resolution 14C dating in a fossil coral is carried out to investigate the "AD 775 14C spike event". Different from the tree ring 14C archives with the 14C spike of ∼15‰ (Δ14C), the 14C spike in the coral shows an abrupt peak of 45‰ and two smaller spikes of Δ14C > 20‰ in half a year in AD 776. And then, the 14C content in coral decreases gradually in AD 777. The peak time of the 14C spike event likely occurs in the summer of AD 776 according to the δ18O variation in coral. High-resolution dating of 14C in coral provides not only a more detail process of the event than that from tree rings, but also the first report of the event from sea ecosystem. Both of them suggest an extraterrestrial origin of the event cause.

  7. Fate of 14C-deltamethrin in lactating dairy cows

    International Nuclear Information System (INIS)

    Fate and residues of radiocarbon (14C) labelled (gem-dimethyl or benzyl) deltamethrin were determined in lactating cows after oral administration for three consecutive days and slaughtering the animals 24 hr after the last dose. Orally administered deltamethrin (10 mg/kg of body weight) appeared to be poorly absorbed, but the insecticide which was absorbed was extensively metabolized and excreted in the bile and urine with very little accumulation in major edible tissues. Approximately 36-43% of the total administered radiocarbon was eliminated in feces mostly as deltamethrin within 24 hr after the last dose. Only 4-6% of the administered 14C was eliminated in urine; and 0.42-1.62% was secreted in the milk. Radiocarbon secreted into milk was higher for the gem-dimethyl portion (0.69 μg/g) than from the benzyl moiety (0.36 μg/g); deltamethrin was the major product in milk (0.1-0.14 μg/g). Radiocarbon residues in tissues were low (<0.1 μg/g), except liver and kidney (1.28-3.19 μg/g), abdominal and subcutaneous fats (0.28-0.62 μg/g). (author)

  8. {sup 1}4C Accelerator mass spectrometry in Brazil

    Energy Technology Data Exchange (ETDEWEB)

    Macario, K.D.; Gomes, P.R.S.; Anjos, Roberto M.; Linares, R.; Queiroz, E.A.; Oliveira, F.M.; Cardozo, L. [Universidade Federal Fluminense (UFF), Niteroi, RJ (Brazil). Inst. de Fisica; Carvalho, C.R.A. [Universidade Federal do Rio de Janeiro (UFRJ), RJ (Brazil). Inst. de Fisica

    2011-07-01

    Radiocarbon Accelerator Mass Spectrometry is an ultra-sensitive technique that enables the direct measurement of carbon isotopes in samples as small as a few milligrams. The possibility of dating or tracing rare or even compound specific carbon samples has application in many fields of science such as Archaeology, Geosciences and Biomedicine. Several kinds of material such as wood, charcoal, carbonate and bone can be chemically treated and converted to graphite to be measured in the accelerator system. The Physics Institute of Universidade Federal Fluminense (UFF), in Brazil will soon be able to perform the complete {sup 14}C-AMS measurement of samples. At the Nuclear Chronology Laboratory (LACRON) samples are prepared and converted to carbon dioxide. A stainless steel vacuum system was constructed for carbon dioxide purification and graphitization is performed in sealed tubes in a muffle oven. Graphite samples will be analyzed in a 250 kV Single Stage Accelerator produced by National Electrostatic Corporation which will be installed in the beginning of 2012. With the sample preparation laboratory at LACRON and the SSAMS system, the Physics Institute of UFF will be the first {sup 14}C-AMS facility in Latin America. (author)

  9. Airy structure in $^{16}$O+$^{14}$C nuclear rainbow scattering

    CERN Document Server

    Ohkubo, S

    2015-01-01

    The Airy structure in $^{16}$O+$^{14}$C rainbow scattering is studied with an extended double folding (EDF) model that describes all the diagonal and off-diagonal coupling potentials derived from the microscopic realistic wave functions for $^{16}$O using a density-dependent nucleon-nucleon force. The experimental angular distributions at $E_L$=132, 281 and 382.2 MeV are well reproduced by the calculations. By studying the energy evolution of the Airy structure, the Airy minimum at around $\\theta$=76$^\\circ$ in the angular distribution at $E_L$=132 MeV is assigned as the second order Airy minimum $A2$ in contrast to the recent literature which assigns it as the third order $A3$. The Airy minima in the 90$^\\circ$ excitation function is investigated in comparison with well-known $^{16}$O+$^{16}$O and $^{12}$C+$^{12}$C systems. Evolution of the Airy structure into the molecular resonances with the $^{16}$O+$^{14}$C cluster structure in the low energy region around $E_{c.m.}$=30 MeV is discussed. It is predicted ...

  10. Dissipation of 14C chlorpyrifos in the rhizosphere of rice

    International Nuclear Information System (INIS)

    The root exudates from the plants contribute to the biodegradation of insecticides. Although, different mechanisms have been proposed, there is no clear elucidation of any mechanism. This study investigates the dissipation of an organophosphorus insecticide, chlorpyrifos in the rhizospheric soil planted with rice plant. Two sets of experimental tanks were maintained with or without plants using soil spiked with 1 mg kg-1 and 10 mg kg-1 of chlorpyrifos. Experiment was conducted for 180 days till the rice plant starts bearing seeds. The 14C activity decreased rapidly in the rhizospheric soil as compare to the non-rhizospheric soil. The total culturable microflora were higher in the rhizospheric than the non-rhizospheric soil. The plant extract had given few counts indicating some negligible amount of chlorpyrifos uptake. The 14C activity in the water was disappeared after 30 days. It was observed that very low amount of residue persisted in soil. This studies revealed that the plants play an important role in the dissipation of the chlorpyrifos from the rice flooded rhizospheric soil. (author)

  11. 14C-glycocholate breath test and pathological digestive transit

    International Nuclear Information System (INIS)

    14C-glycine glycocholate breath test is elegant, atraumatic and detects bacterial overgrowth in the proximal portion of small intestine. In such cases an early increase of specific radioactivity of CO2 occurs in expired air. Ileal bile salts malabsorption can also induce such an increase in principle later. However, a modification of transit (acceleration or paresis) can shift the time of appearance of the physiological 14CO2 peak due to colonic deconjugation of the labelled tracer, leading to a diagnostic error. Microbial overgrowth, gastroparesis, accelerated intestinal transit or malabsorption can complicate diabetes mellitus, especially in the case of diabetic neuropathy. Several of these disorder can coexist. It is possible to detect and quantify all these abnormalities in a single examination by the simultaneous use of labelled glycocholate and sup(99m)Tc DTPA. Oral administration of this mixture allows the measurement of gastric emptying half-time and the scintigraphic visualisation of labelled meal progression. Thus, the association of 14C-glycocholate breath-test and sup(99m)Tc DTPA digestive transit insures a correct interpretation in case of associated abnormalities

  12. Biochemical diagnosis of mucopolysaccharidoses by estimation of intracellular 35S-sulfate accumulation

    International Nuclear Information System (INIS)

    The investigation of 35S-sulfate accumulation and of 35SO4-labelled glycosaminoglucane molecules (chase-experiments) in cultured cells was used in post- and prenatal diagnosis of mucopolysaccharidosis (MPS). Cell lines which accumulate 35S-sulfate can be differentiated by means of cross correction or measurement of enzyme activity. 34 patients with the MPS type I, II, III A, III B and VI, respectively, were diagnosed in this way. Four pregnancies at risk for MPS were prenatally monitored by the sulfate accumulation in cultured amniotic fluid cells. One fetus suffering from MPS II was found. (author)

  13. 32P measurement and dose conversion factor evaluation of activated human hair by criticality accident

    International Nuclear Information System (INIS)

    In order to conduct dose assessment of victims in criticality accidents, a method of fast neutron capture-activated 32P measurement of hair in which samples are treated by a chemical and analytical procedure that takes 9 h and measurement is conducted by liquid scintillation counting is presented. To validate this measurement method, hair samples spiked with a 32P reference source were measured and the results analysed and the optimal sample mass and detection efficiency were determined. To verify the correlation between 32P-specific activity and absorbed dose for spectra with two neutron mean energies, samples collected from three normal individuals were irradiated at various neutron energies and irradiation times using the MC50 Cyclotron of the Korea Institute of Radiological and Medical Sciences. The 32P-specific activity trend of the irradiated hair agreed well with the absorbed doses. Based on the results, dose conversion factors, which were 0.67±0.15 and 0.59±0.06 Gy (Bq g-1)-1 at neutron mean energies of 2.33 and 5.36 MeV, respectively, were calculated as a guide for medical treatment of criticality accident victims. In this study, a method for measuring 32P changes activated by the neutron irradiation of hair samples of criticality accident victims was developed and tested. In addition, a dose conversion factor for two neutron mean energy spectra based on these measurement results was developed. These results agree well with measured absorbed doses from exposure to fast neutron fields. The advantage of the proposed activated hair analysis method based on liquid scintillation counting is that it enables the acquisition of dose information from victims in a short time and with relatively high detection efficiency. In addition, sampling of hair is simpler than it is for other biological samples, and, finally, the conversion factor the authors developed using hair analysis data will be useful for dose assessment in real cases. However, the relation between

  14. Design and construction of a prototype for the obtention of {sup 32} P; Diseno y construccion de un prototipo para la obtencion de {sup 32} P

    Energy Technology Data Exchange (ETDEWEB)

    Alanis M, J. [ININ, Departamento de Materiales Radiactivos, 52045 Ocoyoacac, Estado de Mexico (Mexico)

    2003-12-15

    In the National Institute of Nuclear Research (ININ) it was designed, built and proved a prototype to obtain {sup 32}P in form of H{sub 3} {sup 32}PO{sub 4}, starting from irradiated S{alpha}. The beginning of the prototype it is based on a distillation system in dry of the S{alpha} in nitrogen atmosphere, and in the formation of the ion {sup 32}PO{sub 4}{sup 3-} in acid solution. Due to the handling of radioactive material during the process, the prototype is inside a hot cell and it has a cylindrical oven that opens up lengthwise to the half, with controller of temperature and with a system of empty air for to transport reagents and products. The air-vacuum system is provided of filters and traps. The tests showed a recovery from 14 to 15% of the activity obtained during the irradiation. (Author)

  15. Accelerator mass spectrometry analysis of 14C-oxaliplatin concentrations in biological samples and 14C contents in biological samples and antineoplastic agents

    Science.gov (United States)

    Toyoguchi, Teiko; Kobayashi, Takeshi; Konno, Noboru; Shiraishi, Tadashi; Kato, Kazuhiro; Tokanai, Fuyuki

    2015-10-01

    Accelerator mass spectrometry (AMS) is expected to play an important role in microdose trials. In this study, we measured the 14C concentration in 14C-oxaliplatin-spiked serum, urine and supernatant of fecal homogenate samples in our Yamagata University (YU) - AMS system. The calibration curves of 14C concentration in serum, urine and supernatant of fecal homogenate were linear (the correlation coefficients were ⩾0.9893), and the precision and accuracy was within the acceptance criteria. To examine a 14C content of water in three vacuum blood collection tubes and a syringe were measured. 14C was not detected from water in these devices. The mean 14C content in urine samples of 6 healthy Japanese volunteers was 0.144 dpm/mL, and the intra-day fluctuation of 14C content in urine from a volunteer was little. The antineoplastic agents are administered to the patients in combination. Then, 14C contents of the antineoplastic agents were quantitated. 14C contents were different among 10 antineoplastic agents; 14C contents of paclitaxel injection and docetaxel hydrate injection were higher than those of the other injections. These results indicate that our quantitation method using YU-AMS system is suited for microdosing studies and that measurement of baseline and co-administered drugs might be necessary for the studies in low concentrations.

  16. Forensic applications of {sup 14}C at CIRCE

    Energy Technology Data Exchange (ETDEWEB)

    Marzaioli, F., E-mail: fabio.marzaioli@unina2.it [CIRCE, Dipartimento di Scienze Ambientali, Seconda Universita degli Studi di Napoli and INNOVA, Via Vivaldi 43, 81100 Caserta (Italy); Fiumano, V., E-mail: vittoriofiumano85@libero.it [CIRCE, Dipartimento di Scienze della Vita, Seconda Universita degli Studi di Napoli and INNOVA, Via Vivaldi 43, 81100 Caserta (Italy); Capano, M., E-mail: manuela.capano@unina2.it [CIRCE, Dipartimento di Studio delle Componenti Culturali del Territorio, Seconda Universita degli Studi di Napoli and INNOVA, Piazza S. Francesco, 81055 Santa Maria Capua Vetere, Caserta (Italy); Passariello, I., E-mail: isabella.passariello@unina2.it [CIRCE, Dipartimento di Scienze Ambientali, Seconda Universita degli Studi di Napoli and INNOVA, Via Vivaldi 43, 81100 Caserta (Italy); Cesare, N.De., E-mail: nicola.decesare@unina2.it [CIRCE, Dipartimento di Scienze della Vita, Seconda Universita degli Studi di Napoli and INNOVA, Via Vivaldi 43, 81100 Caserta (Italy); Terrasi, F., E-mail: filippo.terrasi@unina2.it [CIRCE, Dipartimento di Scienze Ambientali, Seconda Universita degli Studi di Napoli and INNOVA, Via Vivaldi 43, 81100 Caserta (Italy)

    2011-12-15

    The decreasing trend of the radiocarbon pulse produced during the atmospheric tests of nuclear weapons (bomb-carbon) coupled with high sensitivity accelerator mass spectrometry (AMS) measurements, drastically increased the precision of radiocarbon age determinations since the second part of the sixties, allowing the application of radiocarbon AMS to a wide range of studies previously not directly involving conventional radiocarbon dating (i.e. food authenticity, forensic, biochemistry). In the framework of authenticity evaluation of artworks, high precision radiocarbon ({sup 14}C) AMS measurements ({Delta}R/R < 0.3%) reduce the conventional uncertainty of the dating to few decades, allowing precise age estimation of materials containing carbon (C). The Centre for Isotopic Research on Cultural and Environmental heritage (CIRCE) during its activity on AMS {sup 14}C dating achieved high precision measurements opening the opportunity to these kinds of applications. This paper presents the main results obtained from radiocarbon measurements on a set of bone samples analyzed for the determination of the post-mortem interval in the framework of an unsolved case investigated by the Rome prosecutor office. The chronological characterization of the wooden support of the 'Acerenza portrait' is also presented with the aim to evaluate its age and to further investigate the possibility to attribute this artwork to Leonardo da Vinci. Bomb-{sup 14}C dating on the lipid and collagen fractions of bones allows the evaluation of the year of the death of the individuals by means of ad hoc calibration data sheet with the typical few years precision and difference between collagen apparent age and the year of death appeared in agreement with the age of one individual estimated by dating of tooth collagen. Conventional radiocarbon dating on both wood and wood extracted cellulose leads to an estimation of the portrait wood board age (2{sigma}) of 1459-1524 AD (57% relative

  17. Preparation and HPLC isolation of L-[U-14C]tryptophan from enzyme hydrolysate labelled with 14C

    International Nuclear Information System (INIS)

    Tryptophan was obtained from biomass of the blue-green alga Synechococcus elongatus cultivated under 14CO2. After partial purification, the protein fraction was subjected to enzymatic hydrolysis using pronase. Semipreparative isolation of L-[U-14C]tryptophan was accomplished on a HPLC column of Separon S Hema 1000 CM, 2% ethanol were added to the eluent, and a precolumn packed with the basic anion exchanger Spheron 1000 DEAE was used. Always after the passage of L-[U-14C]tryptophan, the precolumn was decoupled. The substance was collected in 96% ethanol. After removing the solvent by vacuum evaporation, the sample was analyzed on a column packed with Separon SIX C18 in the eluent of 0.1M-NaH2PO4, 2% methanol. When the desired radiochemical purity was not attained, the sample was purified on Separon SIX C18 using 2% methanol. The final radiochemical purity achieved by using this method is 98%. (P.A.). 5 figs., 2 tabs., 4 refs

  18. Effect of radioactive isotope 32P upon alpha amylase activity and glucose concentration in chickens

    International Nuclear Information System (INIS)

    An attempt has been made to investigate whether alpha amylase activity and glucose concentration in blood plasma can serve as the help in establishing on early diagnosis of organic or functional damage caused by ionizing radiation in chickens. Fifty day old hybrid chickens of heavy 'Jata' breeds of both sexes, were treated by 32P administered intramusculary as sodium orthophosphate in a single dose of 333 MBq per kilogram of body weight. Blood samples was taken from the wing vein on day 1, 3, 5, 7 and 10 after administration of 32P. Alpha amylase activity and glucose concentration were determined spectrophotometrically using kits produced by 'Radonja', Sisak. Alpha amylase activity was decreased and glucose concentration was increased during investigated period. Yet, the further investigations are needed to find out whether these two parameters can be used for early diagnosis of injury in chicken organism by ionizing radiation. (author)

  19. Single-Well Technique using 32P for Determining Direction and Velocity of Groundwater Flow

    International Nuclear Information System (INIS)

    A radiographic method for determining the direction, ∅, and the velocity, v, of groundwater flow has been developed. The radioisotope 32P is injected, as a point or a thin-column source, at the centre of the well by means of a simple device. The injection is performed at the desired depth without disturbing the water. The radioisotope is left to follow the horizontal flow of water. Some of the 32P is adsorbed onto the walls of two parallel detecting screens which are separated by a few centimetres and fitted inside the well. Both the inner and outer screens are radiographed; the darkest parts of the emulsions and the north direction marked on another film give the value of ∅. The blackening of each film in the screens is measured. Velocities are determined either by the displacement method or from the calibration curve of the velocity versus relative blackening. (author)

  20. The expression of foreign gene under the control of cauliflower mosaic virus 35s RNA promoter

    Institute of Scientific and Technical Information of China (English)

    WangHao; BaiYongyan

    1990-01-01

    The promoter region of cauliflower mosaic virus (CaMV) 35s RNA was employed to construct an intermediate expression vector which can be used in Ti plasmid system of Agrobacterium iumefaciens.The original plasmid,which contains a polylinker between CaMV 35s RNA and its 3' termination signal in pUC18 was modified to have another antibiotic resistance marker (kanamycin resistance gene Kmr) to facilitate the selection of recombinant with Ti plasmid.Octopine synthase (ocs) structural gene was inserted into this vector downstream of CaMV 35s RNA promoter.This chimaeric gene was introduced into integrative Ti plasmid vector pGV 3850,and then transformed into Nicotiana tobaccum the chimaeric gene into tobacco cells.In both cases,the expression of ocs gene was demonstrated.The amount of octopine was much more than the nopaline synthesized by nopaline synthase (nos) gene transferred at the same time with Ti plasmid vector.This demonstrated that CaMV 35s RNA promoter is stronger in transcriptional function than the promoter of nos in tobacco cells.

  1. Decomposition of 14C - malathion in three Brazilian soil samples

    International Nuclear Information System (INIS)

    The degradation of 14C-malathion in soil was examined using gas chromatography and radiotracer techniques. About half of the malathion added was degraded within a day in soil from three regions of Brazil. Almost all the radiolabelled material extracted from the Red Latosol (Londrina, PR) was malathion, but metabolites were extracted from the 'Sandy' cerrado soil (Planaltina, DF) and Dark-Red Latosol (Passo Fundo, RS). The proportion of metabolites in the extracts increased until most of the malathion was degraded, after four days. Radiocarbon dioxide was liberated from all three soils at similar rates. When about half of the label had been recovered as carbon dioxide after eight weeks, the rate of evolution diminished. (Author)

  2. Radioisotope labelling of several major insect pest. Dipping the pupae in /sup 32/P solution

    Energy Technology Data Exchange (ETDEWEB)

    Sutrisno, S. (National Atomic Energy Agency, Jakarta (Indonesia). Pasar Djumat Research Centre)

    1981-12-01

    Radioisotope uptake by insects could take place through various parts i.e. mouth, cuticula, intersegmental, secretion and excretion organs. Usually insects are labelled internally by feeding them on an artificial diet containing radioisotope solution. Labelling of several insect pests of cabbage (Crocidolomia binotalis) Zell and Plutella maculipennis Curt and rice (Chilo suppressalis Walker) by dipping of the pupae in /sup 32/P solution showed a promising result. Pupae of Crocidolomia binotalis Zell dipped in 3 ml solution of /sup 32/P with specific activities of 1, 3, 5 and 7 ..mu..Ci/ml had developed labelled adults of sufficiently high radioactivity levels for ecological studies. Similar results were also obtained with Plutella maculipennis Curt and Chilo suppressalis Walker with doses of 1, 3, 5, 7 and 9 ..mu..Ci/ml /sup 32/P solution. The best doses for radioisotope labelling by dipping of the insects Crocidolomia binotalis Zell, Plutella maculipennis Curt, and Chilo suppressalis Walker were 1, 9, and 7 ..mu..Ci/ml respectivelly.

  3. DNA Labeled with 32P for Detection of the Resistance of Mycobacterium Tuberculosis to Isoniazid

    International Nuclear Information System (INIS)

    DNA labeled by 32P for detection of the resistance of M.tuberculosis to isoniazid has been carried out with molecular biology technique based on nuclear science. Tuberculosis (TB) is the first rank of death caused infectious diseases in Indonesia. One case of difficulties in controlling TB is the spreading of M.tuberculosis which resistant to the drug such as isoniazid. In this research, resistance to isoniazid can be detected by analyzing inh A gene, which is encoding isoniazid resistance. Analysis was done with polymerase chain reaction (PCR) technique to amplify deoxyribonucleic acid (DNA) from inhA gene and was labeled with alpha 32P deoxy cytosine triphosphate ([α- 32P]dCTP). Amplified product of DNA was analyzed with single strand conformation polymerism (SSCP) technique based on the alteration of DNA band mobility in acrylamide gel after visualization with autoradiography. Analyses that have been done on 100 samples, it was found that 13.0% of them were suspected resistant to isoniazid. Molecular biology technique could be used to detect resistance in a short time and specific, and could be used as supporting data in TB patient treatment. The alteration of mobility of DNA band inhA gene could be used for analyzing the resistance M.tuberculosis to isoniazid. (author)

  4. Chemical digestion and radionuclidic assay of TiNi-encapsulated 32P intravascular brachytherapy sources

    International Nuclear Information System (INIS)

    A very quantitative, destructive assay procedure was devised for accurately measuring the 32P activity content of TiNi-encapsulated intravascular brachytherapy sources and was applied to four different sources (termed 'seeds') which were developed and provided by Guidant Intravascular Intervention (formerly NeoCardia). These seeds are intended for use in the prophylactic treatment of restenosis following balloon angioplasty in heart-disease patients. The assays involved the dissolution of the TiNi jacket, extraction of the activity from the internal 32P-containing source material, quantitative solution transfers, and a gravimetrically-based dilution; followed by liquid scintillation (LS) spectrometry of the resulting master solution with 3H-standard efficiency tracing using composition-matched LS cocktails. The LS spectrometry utilized a previously-developed method for resolving the always-present 33P impurity. The protocol included provisions for accounting for all possible losses of 32P in the digestion procedure (based on radiochemical tracing experiments), for any unrecovered activity in the remaining source material, and for any residual activity in the solution-transfer and containing vessels. Sections of the TiNi jackets adjacent to the cut-off active seed portions were also assayed for any contained activity. Such destructive assays were required for relating measurements of the absorbed dose spatial distribution for the seeds to theoretic dose modelling and for establishing calibration factors for subsequent non-destructive radionuclidic measurements on the seeds

  5. Effect of /sup 32/P treatment for polycythaemia vera on blood lymphocyte subpopulations and their functions

    Energy Technology Data Exchange (ETDEWEB)

    Petrini, B.; Wasserman, J.; Stedingk, L.V.; Blomgren, H.; Svedmyr, E.; Schnell, P.O.

    1987-01-01

    The influence of /sup 32/P treatment on the blood lymphocyte population was examined in 16 patiens with polycythaemia vera who had not previously been treated with cytotoxic drugs or irradiation. Before treatment the lymphocyte counts were within the normal range but the expression of certain membrane structures, as detected by monoclonal antibodies directed against total T cells (CD 3 and 5), helper/inducer (CD 4) and suppressor/cytotoxic T cells (CD 8), were slightly reduced. In addition, mitogenic responses of the lymphocytes to PHA and PWM-induced Ig secretion were severely impaired. Following a single oral dose of /sup 32/P (150-305 MBq), which was shown to normalize the production of erythrocytes and/or platelets, the blood lymphocyte counts were reduced by approximately 40% 12 wk after treatment. Subset analysis showed that the proportion of B cells, as identified by monoclonal antibodies (CD 20), was reduced to the highest relative extent. On the other hand, lymphocytes expressing the above T cell markers were somewhat increased. /sup 32/P treatment sharply increased PHA reactivity but it further reduced PWM-induced Ig secretion. The latter observation was in line with the finding that serum concentrations of Ig were reduced following treatment.

  6. Changes of the blood lymphocyte population following sup 32 P treatment for polycythemia vera

    Energy Technology Data Exchange (ETDEWEB)

    Blomgren, H.; Svedmyr, E. (Radiumhemmet Karolinska Hospital, Stockholm (Sweden)); Petrini, B.; Wasserman, J.; Stedingk, L.-V. von (The Stockholm County Council, Central Microbiological Laboratory, Stockholm (Sweden))

    1990-01-01

    Orally administrated NA{sub 2} {sup 32}PO{sub 4} mainly accumulates in bone marrow where it emits {beta}-particles which may damage cells. Previously, we showed that {sup 32}P treatment for polycythemia vera (PVC) increased the phytohemagglutinin reactivity and proportions of T cells in the blood. Now we have examined the effects of {sup 32}P treatment for PCV on natural killer (NK) and B-lymphocyte subsets which are considered to undergo their maturation in bone marrow. A mean isotope dose of 240 MBq given to 14 patients reduced the peripheral lymphocyte counts to 60% at 6 weeks. B cells and NK cells were reduced to the highest relative extent followed by HNK-1 cells and T cells. Although the proportion of NK cells was reduced to 50% there was no concomitant reduction of NK activity against K562 cells. Pokeweed mitogen-triggered secretion of IgM was significantly reduced, but not that of IgG or IgA. It is suggested that lymphocytes which mature in bone marrow may be affected to the highest extent by {sup 32}P treatment in PCV. (author).

  7. Redistribution of paclobutrazol-14C in soil and plant

    Energy Technology Data Exchange (ETDEWEB)

    Costa, Maria Aparecida; Tornisielo, Valdemar Luiz; Regitano, Jussara Borges [Centro de Energia Nuclear na Agricultura (CENA), Piracicaba, SP (Brazil). Lab. de Ecotoxicologia]. E-mail: macosta@cena.usp.br; vltorrnis@cena.usp.br; regitano@cena.usp.br

    2007-07-01

    Paclobutrazol (PBZ) is important to the mango culture since it works as a growth regulator that inhibits gibberellins synthesis controlling the growth of the trees and thus reducing pruning and manipulation during cultivation. Although PBZ has been used for years in mango in Brazil, there are no studies evaluating its environmental fate under Brazilian conditions. Therefore, the objective of the present work is to evaluate the redistribution of PBZ and its metabolites in soil and plant. For this experiment, radiolabeled ({sup 14}C-PBZ) was used once this technique allows detention of minimum amounts of residues in both soil and plant. In addition, plants were cultivated in vessels (100 L and 1 plant /vessel) and the PBZ were applied to the soils at the recommended rate of 1,0 kg ha{sup -1}, having radioactive concentration of 2,0 MBq/vessel. In order to evaluate PBZ redistribution, the volumes of water percolated with rainfall and senescent leaves were collected to monitor their {sup 14}C-residue concentration by liquid scintillation spectrometry (LSS). In parallel, the sorption and leaching potential of PBZ was determined in order to support the previous study. The results showed that PBZ presented relatively low mobility (0.12 % of the applied amount) and high sorption (91.9 % of the applied amount) in the studied soil, being minimal its leached amount; and that majority of the soil applied radioactivity were redistributed in the plant leaves (1.08% of the applied amount). Needing more inquiries in relation to the contamination of the soil and rain water percolated in period of September, 2nd, 2006 to January, 8th, 2007 was of the 0.06% in relation applied radioactivity being very next the radioactivity to deep, indicating that the product still is not being leached during rains. (author)

  8. The experimental study of 32P-colloid perfusion therapy in the animal-models of chronic maxillary sinusitis

    International Nuclear Information System (INIS)

    Objective: To search for the mechanism of 32P-colloid perfusion therapy in the animal models of chronic maxillary sinusitis. Methods: 32P-colloid were injected into the male sheep maxillary sinuses of the animal-models of chronic maxillary sinusitis in different dosage group. The changes of bacteria and mucosael pathomorphology were observed by periodic germiculture and pathology in 1,3,6 months after injection. Results: After 32P-colloid perfusion therapy, the amounts of bacterial species and chronic phlogistic cells were remarkable reduced, and the structure of cilia cells did not change. The curable rate was 83.3% in 6 months. There were remarkable difference in groups. Conclusions: 32P-colloid was provided with antibiosis and reducing chronic phlogistic responses. The authors had found the optimal dose of 32P-colloid perfusion in the maxillary sinuses through the study. The curable rate of single dose of 32P-colloid perfusion in the maxillary sinuses was higher than other therapy, 32P-colloid perfusion was simple and convenient. There was high selectivity of 32P in the target organ, when there was no effect on other important organs through radiobiological measurement. (authors)

  9. Design and construction of a prototype for the obtention of 32P

    International Nuclear Information System (INIS)

    The 32 P are a pure emitting radioisotope of maximum energy of 1.71 MeV with half life of 14.28 days that he has applications in the industry, in agriculture, in medicine, in biology and in ecology (6,11,12,13,17,21,22,23,24,25,26,27,28,29,30,31,32 33).The 32 P can be used in the industry like radiotracer in the investigation of some operations and processes and as element of measurement of some industrial meters. In agriculture is used as radiotracer (29) in the investigation of diverse biological processes that have to do with the production of diverse nutritious products. In medicine has uses but very therapeutic mainly in the treatment of some become cancerous (28, 31, 25, 27) in the diagnosis of blood disorders (24) and like part of materials of production of aortic prosthesis (6). The 32 P are also used in the molecular investigation in biology and in genetics (33), and in studies of ecosystems (32) and of DNA (22). One can obtain the 32 P by means of diverse nuclear reactions depending on the material used as matter it prevails, since it doesn't exist in the nature. But anyone in the ways of obtaining it it should imply a process of radiochemical separation that involves so many steps like they are required, depending on the material used as matter prevails, of the purity with which he wants himself to obtain and of the resources that it has available. The objective of this work was design, to build and to prove a prototype to obtain the 32 P to leave of the irradiation of S α with fast neutrons at experimental level, which implies also to design a process that contemplates diverse stages and procedures for each one of them. The process was outlined in five stages: matter purification prevails, preparation of irradiation capsules, irradiation of irradiation capsules, transport and opening capsules of irradiation and radiochemical separation. In the last stage it was where uses the prototype of radiochemical separation in basis to the outlined process and

  10. Preparation of highly concentrated super-hot (γ-32P)ATP using small-scale ion-exchange chromatography

    International Nuclear Information System (INIS)

    In order to obtain a highly concentrated, pure and super-hot [γ-32P]ATP, we improved the purification method of super-hot [γ-32P]ATP which was synthesized by the method of Johnson and Walseth (1979). The super-hot [γ-32P]ATP was synthesized in a relatively large volume (2 ml) of reaction mixture and purified using semi-micro scale anion exchange chromatography (Dowex 1 x 2, 60 - 70 μl column volume). In combination with washing the reaction product with certain organic solvents, this chromatography technique makes it possible to obtain a highly concentrated and pure super-hot [γ-32P]ATP (approx. 7000 Ci/mmol; 20 - 30 mCi/ml) from [32P]Pi of any commercial source in a good yield. (author)

  11. Urvina Bay, Galapagos Coral Radiocarbon (delta 14C) Data for 1956 to 1982

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Urvina Bay coral radiocarbon (14C) timeseries. (90 deg W, 0.5 deg S) Coral radiocarbon (Delta-14C) on untreated, low-speed drilled samples. Precision is +/- 4 per...

  12. Defective [U-14 C] palmitic acid oxidation in Duchenne muscular dystrophy

    International Nuclear Information System (INIS)

    Compared with normal skeletal muscle, muscle from patients with Duchenne dystrophy had decreased [U-14 C] palmitic acid oxidation. [1-14 C] palmitic acid oxidation was normal. These results may indicate a defect in intramitochondrial fatty acid oxidation

  13. Simulation of 14C in IAP/LASG L30T63 Ocean Model

    Institute of Scientific and Technical Information of China (English)

    LI Qingquan; SHI Guangyu

    2005-01-01

    14C plays an important role in the study of ocean circulation and anthropogenic CO2. Radioactive 14C is usually used in ocean carbon circulation model to test the physical performance of model. In the present paper, a 14C model is established and coupled with the IAP/LASG L30T63 global ocean circulation model to simulate the distribution of natural 14C in oceans and the penetration and uptake of 14C in oceans after industrial revolution and nuclear bomb test. The simulation of natural 14C reveals the basic characteristics of oceanic ventilation. However, simulation value is "younger" than observation in the Pacific and Indian Oceans, and "older" than observation in the Atlantic deep ocean. The simulation of bomb 14C agrees well with GEOSECS observation, but the volume inventory and averaged penetration depth of bomb 14C in oceans are smaller than observation. The probable reasons for these discrepancies are analyzed.

  14. Synthesis of two 14C-labeled catechol-o-methyltransferase inhibitors

    International Nuclear Information System (INIS)

    14C-labelled 3-(3,4-dihydroxy-5-nitrophenylmethylidene)-2,4-pentanedione and 14C-labelled E-N,N-diethyl-2-cyano-3-(3,4-dihydroxy-5-nitrophenyl)acrylamide have been synthesized from [carbonyl-14C]vanillin. (author)

  15. Disposition of [14C]γ-cyclodextrin in germ-free and conventional rats

    NARCIS (Netherlands)

    Bie, A.T.H.J. de; Ommen, B. van; Bär, A.

    1998-01-01

    The absorption, disposition, metabolism, and excretion of 14C-labeled γ-cyclodextrin ([14C]γ-CD) was examined in four separate experiments with Wistar rats. In experiment 1, [14C]γ-CD (25 μCi, 600 mg/kg body wt) was administered intravenously to four male and four female conventional rats. In experi

  16. {sup 14} C dating by using mass spectrometry with particle accelerator; Datacao por {sup 14} C utilizando espectrometria de massa com acelerador de particulas

    Energy Technology Data Exchange (ETDEWEB)

    Santos, G.M.; Gomes, P.R.S. [Universidade Federal Fluminense, Niteroi, RJ (Brazil). Inst. de Fisica]. E-mail: paulogom@if.uff.br; Yokoyama, Y. [Australian National Univ., Canberra (Australia). Research School of Earth Science; Tada, M.L. di; Cresswell, R.G.; Fifield, L.K. [Australian National Univ., Canberra (Australia). Dept. of Nuclear Physics

    1999-03-01

    The different aspects concerning the {sup 14} C dating are described, including the cosmogenic origin of {sup 14} C, its production and absorption by matter, the procedures to be followed for the age determination and the associated errors, particularly by the Accelerator Mass Spectrometry (AMS) technique, and the different steps of the sample preparation process. (author)

  17. 14C determination in different bio-based products

    Science.gov (United States)

    Santos Arévalo, Francisco-Javier; Gómez Martínez, Isabel; Agulló García, Lidia; Reina Maldonado, María-Teresa; García León, Manuel

    2015-10-01

    Radiocarbon determination can be used as a tool to investigate the presence of biological elements in different bio-based products, such as biodiesel blends. These products may also be produced from fossil materials obtaining the same final molecules, so that composition is chemically indistinguishable. The amount of radiocarbon in these products can reveal how much of these biological elements have been used, usually mixed with petrol derived components, free of 14C. Some of these products are liquid and thus the handling at the laboratory is not as straightforward as with solid samples. At Centro Nacional de Aceleradores (CNA) we have tested the viability of these samples using a graphitization system coupled to an elemental analyzer used for combustion of the samples, thus avoiding any vacuum process. Samples do not follow any chemical pre-treatment procedure and are directly graphitized. Specific equipment for liquid samples related to the elemental analyzer was tested. Measurement of samples was performed by low-energy AMS at the 1 MV HVEE facility at CNA, paying special attention to background limits and reproducibility during sample preparation.

  18. The 14C-AMS Laboratory at IF-UFF

    Energy Technology Data Exchange (ETDEWEB)

    Macario, K.D.; Gomes, P.R.S.; Anjos, R.M.; Linares, R.; Carvalho, C.R.A.; Castro, M.D.; Oliveira, F.M.; Alves, E.Q.; Chanca, I.S. [Universidade Federal Fluminense (UFF), Niteroi, RJ (Brazil)

    2012-07-01

    Full text: In 2009 a radiocarbon sample preparation laboratory dedicated to Accelerator Mass Spectrometry was installed at the Physics Institute of the Fluminense Federal University. At the Radiocarbon Laboratory samples of several kinds of materials such as charcoal, sediments, wood and shells go through specific chemical treatment and conversion to carbon dioxide. Graphite reduction is performed in sealed Pyrex tubes, using Zinc, Titanium Hydrate, and iron catalyst within an inner tube. Samples have been successfully produced yielding fluffy homogeneous graphite leading to high and stable currents in the ion source. For sample measurement an accelerator system produced by the National Electrostatics Corporation (NEC), was installed in the Physics Institute. The machine, specially developed to carbon analysis, is the State of the Art in 14C - AMS studies and its acquisition represent a very important step for Brazil towards the development of science and technology regarding radiocarbon studies. The system includes an open air deck 250 kV single stage electrostatic accelerator with magnetic and electrostatic analyzers that enable isotope separation and detection. Radiocarbon concentrations are measured to 1 part in 10{sup 15} with precision of 0.3 The Nuclear Applied Physics group on Chronological Studies is now performing multidisciplinary research in collaboration with Brazilian and foreign groups from several fields of science such as Archaeology, Geophysics, Oceanography and Biology, in studies on the evolution of marine, terrestrial and Antarctic ecosystems. (author)

  19. Fate of 14C-carbofuran in lactating goats

    International Nuclear Information System (INIS)

    Radiocarbon labeled carbofuran was administered orally to lactating goats at 0.03 mg/kg (single dose), 0.5 and 1.0 mg/kg/day for 7 days, and at 5.0 ppm in the diet (2 kg feed intake/day basis) for 15 days. Radioactive residues were rapidly excreted in the urine after treatment. The major residue identified in urine of the treated goats was carbofuran phenol, a non-toxic metabolite. Only about 1% of the doses was eliminated in the feces of the treated goats. Residues of (14C)carbofuran were secreted into milk, but these residues were in all cases very low. Radioactive residue occurred in tissues at low levels, with patterns as follows: omental fat>liver>subcutaneous fat>kidney>brain>heart>biceps femoris>longissimus dorsi. The residue stored in fat was identified as carbofuran. The liver contained hydroxy carbofuran and one unidentified metabolite but no carbofuran. The other tissues contained only phenolic metabolites. These studies strongly indicate that proper carbofuran use in rice in the Philippines will present no risks to goats that consume treated crop residues, or to humans who consume meat or milk from exposed animals. (author)

  20. Fate of 14C-Labelled Triazine Herbicides in Plants

    International Nuclear Information System (INIS)

    The resistance of certain plant species to triazines is referred to their ability to metabolize the herbicide. In the case of the chloro-triazines the conversion to the 2-hydroxy analogue, a non-phytotoxic product, has been described in the literature already. Studies which have been devoted to the metabolic breakdown of methylmercaptotriazines revealed a conversion to the 2-hydroxy compound to a smaller extent and in a way different from that established with the chloro-triazines. The in vitro oxidation of prometryne (2-methylmercapto-4, 6-bisisopropylamino-striazine) yields the sulphoxy and sulphono analogues which easily hydrolyse to 2-hydroxypropazine. The occurrence of these compounds in peas injected with 14C-prometryne could be established. Some recent findings concerning the occurrence of further metabolites with an intact triazine ring suggest that dealkylation or deamination of the side chains in the 4- and 6-position have to be considered too. Methods used in studying the metabolism of triazines and for the determination of 14CO2 released from treated plants are discussed. (author)

  1. Photolysis of 14C-sulfadiazine in water and manure.

    Science.gov (United States)

    Sukul, Premasis; Lamshöft, Marc; Zühlke, Sebastian; Spiteller, Michael

    2008-03-01

    Photolysis of 14C-sulfadiazine in aqueous solution under simulated sunlight followed first-order kinetics. The impact of H2O2, humic acid, fulvic acid and acetone to enhance the photodegradation of sulfadiazine (SDZ) was studied. Six photoproducts, 4-OH-SDZ, 5-OH-SDZ, N-formyl-SDZ, 4-[2-iminopyrimidine-1(2H)-yl] aniline, 2-aminopyrimidine, and aniline were identified. Extrusion of SO2 was found to be the main degradation process during irradiation. These photoproducts can occur in water and soil upon sunlight exposure, when soil is treated with SDZ contained in manure. Due to photodegradation the experimental half-life of the SDZ in water was 32h and in the presence of photosensitizers the half-life values were 19.3-31.4h, 17.2-31.4h, 12.6-29.8h, and 3.8-30.7h for H2O2, humic acid, fulvic acid, and acetone, respectively depending on the concentration of the photosensitizers. The presence of photosensitizers markedly reduced SDZ persistence, indicating that indirect photolytic processes are important factors governing the photodegradation of SDZ in aqueous environments. Investigation revealed further persistence behavior of SDZ in manure. The half-life value of SDZ in manure was 158h. PMID:18076971

  2. Radioactive sputter cathodes for {sup 32}P plasma-based ion implantation

    Energy Technology Data Exchange (ETDEWEB)

    Fortin, M.A. [INRS-EMT (Universite du Quebec), 1650 boul. Lionel Boulet, Varennes, Quebec, J3X 1S2 (Canada)]. E-mail: fortin@bms.uu.se; Paynter, R.W. [INRS-EMT (Universite du Quebec), 1650 boul. Lionel Boulet, Varennes, Quebec, J3X 1S2 (Canada); Sarkissian, A. [Plasmionique Inc., 1650 boul. Lionel Boulet, Varennes, Quebec, J3X 1S2 (Canada); Stansfield, B.L. [INRS-EMT (Universite du Quebec), 1650 boul. Lionel Boulet, Varennes, Quebec, J3X 1S2 (Canada)

    2006-05-15

    The development of clinical treatments involving the use of beta-emitting millimetric and sub-millimetric devices has been a continuing trend in nuclear medicine. Implanted a few nanometers below the surface of endovascular implants, seeds or beads, beta-emitting radioisotopes can be used in a variety of biomedical applications. Recently, new technologies have emerged to enable the rapid and efficient activation of such devices. A pulsed, coaxial electron cyclotron resonance plasma reactor was designed and tested to demonstrate the feasibility of plasma-based radioactive ion implantation (PBRII). It has been shown that such plasma reactors allow for the implantation of radioisotopes ({sup 32}P) into biomedical devices with higher efficiencies than those obtained with conventional ion beams. Fragments containing radioactive atoms are produced in the implanter by means of a negatively biased solid sputter cathode that is inserted into an argon plasma. Dilute orthophosphoric acid solutions (H{sub 3} {sup 32}PO{sub 4}) are used for the fabrication of flat sputter targets, since they offer a high radioisotope content. However, the aggregation of the radioactive solute into highly hygroscopic ring-like deposits rather than flat, thin radioactive films is observed on certain substrates. This article describes the effect of this nonuniform distribution of the radioisotopes on the efficiency of PBRII, and presents a technique which enables a better distribution of {sup 32}P by coating the substrates with iron. The iron coating is shown to enable optimal radioisotope sputtering rates, which are essential in {sup 32}P-PBRII for the efficient activation of millimetric biomedical devices such as stents or coils.

  3. A rehabilitated greenhouse for 32P radioisotope studies and training in Seibersdorf

    International Nuclear Information System (INIS)

    Full text: Two major activities of the Soil Science Unit in Seibersdorf are to develop and test isotope methodologies and guidelines to support CRPs and TCPs, and to conduct training to strengthen the analytical and professional capabilities of Member States. This is achieved through regional, interregional and laboratory training. Whereas development of methodologies and guidelines for stable isotopes such as (13C, 15N, 18O) in the Unit has advanced in the area of soil-water-nutrient plant continuum, the use of isotopes of phosphorus (32P, 33P) has received little attention in the Unit during the last ten years. The main reason for this has been the lack of a greenhouse and laboratories, that conform to the required safety standards for conducting experiments because of the radioactive nature of the phosphorus isotopes. In most of the developing countries where P bio-availability in the soil is low, the use of 32P and 33P is crucial to understanding P dynamics in soil, and to quantify P pools that can be mobilized by crop genotypes with superior nutrient resource recovery. In response to a demand from Member States to train fellows in the use of P isotopes, and the need to conduct research to support the on-going CRP on Selection and Evaluation of Food (Cereal and Legume) Crop Genotypes Tolerant to Low Nitrogen and Phosphorus Soils through the Use of Isotopic and Nuclear-related Techniques (D1.50.10), the Soil Science Unit has refurbished an old glasshouse (new ventilation and cooling systems, floor renovation etc) and a laboratory to a Type B radiation standard. Fellowship training in the use of 32P and 33P radio-isotopes for soil P dynamics and P nutrition experiments, safety precautions, sample preparation, measurements using a liquid scintillation counter and calculations, will now be conducted at the Soil Science Unit in Seibersdorf. (author)

  4. Biosynthesis of lutropin in ovine pituitary slices: incorporation of [35S]sulfate in carbohydrate units

    International Nuclear Information System (INIS)

    Sulfate incorporation into carbohydrate of lutropin (LH) has been studied in sheep pituitary slices using H2(35)SO4. Labeled ovine LH was purified to homogeneity by Sephadex G-100 and carboxymethyl-Sephadex chromatography from both the incubation medium and tissue extract. Autoradiography of the gel showed only two protein bands which comigrated with the alpha and beta subunits of ovine LH in both the purified ovine LH and the immunoprecipitate obtained with LH-specific rabbit antiserum. Furthermore, [35S]sulfate was also incorporated into several other proteins in addition to LH. The location of 35SO/sub 2-(4)/ in the oligosaccharides of ovine LH was evidenced by its presence in the glycopeptides obtained by exhaustive Pronase digestion. The location and the point of attachment of sulfate in the carbohydrate unit were established by the isolation of 4-O-[35S]sulfo-N-acetylhexosaminyl-glycerols and 4-O-[35S] sulfo-N-acetylglucosaminitol from the Smith degradation products and by the release of 35SO/sub 2-(4)/ by chondro-4-sulfatase. Thus, the present line of experimentation indicates the presence of sulfate on both the terminal N-acetylglucosamine and N-acetylgalactosamine in the oligosaccharide chains of the labeled ovine LH

  5. Atmospheric [{sup 14}C]CO{sub 2} variations in Japan during 1982-1999 based on {sup 14}C measurements of rice grains

    Energy Technology Data Exchange (ETDEWEB)

    Shibata, Setsuko [Research Center for Radiation and Radioisotopes, Osaka Prefecture University, 1-2 Gakuen-cho, Sakai, Osaka 5998570 (Japan)]. E-mail: sshibata60@yahoo.co.jp; Kawano, Eiko [Research Center for Radiation and Radioisotopes, Osaka Prefecture University, 1-2 Gakuen-cho, Sakai, Osaka 5998570 (Japan); Nakabayashi, Takeshige [Research Center for Radiation and Radioisotopes, Osaka Prefecture University, 1-2 Gakuen-cho, Sakai, Osaka 5998570 (Japan)

    2005-08-01

    {sup 14}C in rice grains is a useful tracer of atmospheric {sup 14}C(CO{sub 2}). {sup 14}C measurement in rice grains for 17 years during 1982-1999 reveals the following. There is negative correlation between {delta}{sup 14}C and the population densities of localities in Japan. Under-populated areas in the northern area of Japan and Okinawa remained clean in the 1990s. The {sup 14}C(CO{sub 2}) decline rates at those areas are near to that of Shauinsland. A latitudinal effect due to Chinese nuclear tests is observed in 1982. Small Seuss effects is observed at the middle latitudes in East Asia after 1995.

  6. Detection of irradiation induced modifications in foodstuff DNA using 32p post-labelling

    International Nuclear Information System (INIS)

    DNA post-labelling has been used successfully to detect damage to DNA caused by a range of damaging agents. The assay results in a fingerprint of changes induced in DNA which might, in principle, be useful as a test for the detection of the irradiation of foods. The authors present their DNA extraction and 32p post-labelling methods from chicken or cooked prawn samples and their analysis method (High Performance liquid chromatography). It's hoped that these results could form the basis of a test to detect if foods have been irradiated

  7. Studies on absorption and translocation of phosphorus using radioactive superphosphate (32P) in coffee plants

    International Nuclear Information System (INIS)

    Absorption and translocation (downward as well as lateral) of phosphate ions from foliar applied superphosphate solution (pH 6.5, labelled with 32P) were considerably higher in Coffea arabica L. cv.S. 795 than in Coffea canephera Pierre cv.S. 274 plants. The differential absorption and translocation of phosphate to various plant parts and its accumulation in enlarged flowers buds suggest the possibility that the requirement of phosphorus for flower bud enlargement and blossom (anthesis) is higher in arabica than in robusta. (auth.)

  8. Nine-step synthesis of (/sup 14/C)flupirtine maleate labeled in the pyridine ring

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Y.M.; Kucharczyk, N.; Sofia, R.D.

    1987-01-01

    A nine-step procedure for microscale synthesis of ethyl 2-amino-6-brace((4-fluorophenyl)methyl)aminobrace-3-pyridinyl-2,6-/sup 14/C carbamate maleate, (/sup 14/C)flupirtine maleate, was developed. The synthesis started with potassium cyanide-/sup 14/C and 1,3-dibromopropane making the following intermediates: glutarontrile-/sup 14/C, glutarimide-/sup 14/C, 2,6-dichloropyridine-2,6-/sup 14/C, 2,6-dichloro-3-nitro-pyridine-2,6-/sup 14/C, 2-amino-3-nitro-6-chloropyridine-2,6-/sup 14/C, 2-amino-3-nitro-6-(p-fluorobenzylamino)pyridine-2,6-/sup 14/C, 2,3-diamino-6-(p-fluorobenzylamino)pyridine-2,6-/sup 14/C, and ethyl 2-amino-6-brace((4-fluorophenyl)-methyl)aminobrace-3-pyridinyl-2,6-/sup 14/C carbamic acid ester hydrochloride. The overall yield was 6.3% (5.4 mCi), and the radioactivity was 99.8% as determined by high performance liquid chromatography and liquid scintillation counting.

  9. A nine-step synthesis of [14C]flupirtine maleate labeled in the pyridine ring

    International Nuclear Information System (INIS)

    A nine-step procedure for microscale synthesis of ethyl 2-amino-6-brace[(4-fluorophenyl)methyl]aminobrace-3-pyridinyl-2,6-14C carbamate maleate, [14C]flupirtine maleate, was developed. The synthesis started with potassium cyanide-14C and 1,3-dibromopropane making the following intermediates: glutarontrile-14C, glutarimide-14C, 2,6-dichloropyridine-2,6-14C, 2,6-dichloro-3-nitro-pyridine-2,6-14C, 2-amino-3-nitro-6-chloropyridine-2,6-14C, 2-amino-3-nitro-6-(p-fluorobenzylamino)pyridine-2,6-14C, 2,3-diamino-6-(p-fluorobenzylamino)pyridine-2,6-14C, and ethyl 2-amino-6-brace[(4-fluorophenyl)-methyl)aminobrace-3-pyridinyl-2,6-14C carbamic acid ester hydrochloride. The overall yield was 6.3% (5.4 mCi), and the radioactivity was 99.8% as determined by high performance liquid chromatography and liquid scintillation counting. (author)

  10. 14C ages of Omuroyama volcano, Izu Peninsula

    International Nuclear Information System (INIS)

    A partly carbonized wood trunk was discovered below the Omuroyama tephra covered by a lava, and it was dated to be 3,700±100 y. B.P., by the benzene liquid scintillation method for radiocarbon age determination. We have investigated the circumstance of the discovery of the wood sample based on an interview of the person who collected the sample during his operation of building construction. According to him, the wood specimen was found at 1.5-2 m depth beneath the ground level when the operator removed the massive blackish lava block. This specimen was laid down covered by black sandy pebbles. The size of the wood trunk was 105 cm long and 45 cm and 35 cm along wide and short diameter, respectively. We also revealed the burial environment of the wood to be related with the Omuroyama tephras and lava flow, based on our volcanostratigraphic observation of the surrounding area. The tephras covering the trunk were identified as the Omuroyama tephra B, C, and D, which were defined by Koyano et al. (1996) around this area, and these tephras were covered by the Omuroyama lava flow II (Koyano et al., 1996). The wood trunk was mostly fresh and only its branch was burned. It can be estimated that the trunk has been preserved surrounded by ground water, since several tons of ground water gushed out when the aquifer was opened for construction. On this context, this trunk was buried at the early stage of the volcanism of Omuroyama volcano covered by the tephras, and later also covered by the Omuroyama lava II. We can not conclude that the burned branch is ascribed to direct burning by the Omuroyama lava flow II but this 14C dating resultant is also concordant all archaeological evidences reported. (author)

  11. {sup 14}C ages of Omuroyama volcano, Izu Peninsula

    Energy Technology Data Exchange (ETDEWEB)

    Saito, Toshihito; Takahashi, Shuichi [Shizuoka Univ. (Japan). Graduate School of Science and Engineering; Wada, Hideki [Shizuoka Univ., Hamamatsu (Japan). Faculty of Engineering

    2003-05-01

    A partly carbonized wood trunk was discovered below the Omuroyama tephra covered by a lava, and it was dated to be 3,700{+-}100 y. B.P., by the benzene liquid scintillation method for radiocarbon age determination. We have investigated the circumstance of the discovery of the wood sample based on an interview of the person who collected the sample during his operation of building construction. According to him, the wood specimen was found at 1.5-2 m depth beneath the ground level when the operator removed the massive blackish lava block. This specimen was laid down covered by black sandy pebbles. The size of the wood trunk was 105 cm long and 45 cm and 35 cm along wide and short diameter, respectively. We also revealed the burial environment of the wood to be related with the Omuroyama tephras and lava flow, based on our volcanostratigraphic observation of the surrounding area. The tephras covering the trunk were identified as the Omuroyama tephra B, C, and D, which were defined by Koyano et al. (1996) around this area, and these tephras were covered by the Omuroyama lava flow II (Koyano et al., 1996). The wood trunk was mostly fresh and only its branch was burned. It can be estimated that the trunk has been preserved surrounded by ground water, since several tons of ground water gushed out when the aquifer was opened for construction. On this context, this trunk was buried at the early stage of the volcanism of Omuroyama volcano covered by the tephras, and later also covered by the Omuroyama lava II. We can not conclude that the burned branch is ascribed to direct burning by the Omuroyama lava flow II but this {sup 14}C dating resultant is also concordant all archaeological evidences reported. (author)

  12. Activity measurement of /sup 33/P and /sup 32/P radionuclide mixture

    Energy Technology Data Exchange (ETDEWEB)

    Hanker, I.; Kansky, Z.

    1984-04-01

    The possibilities are briefly summed up of measuring mixtures of /sup 33/P and /sup 32/P with special regard to the method of simultaneous determination of both radionuclides in a liquid scintillator. This method was experimentally tested for special detection sensitivity and intended special applications in plant physiology and biochemistry using a dioxane scintillator (SLD-31, Spolana Neratovice, CSSR) and a Packard Tri-Carb 300 C, USA. The method gave erroneous results. The main cause of the errors in measurements of the /sup 33/P and /sup 32/P mixture in the SLD-31 was the adsorption of radionuclides on the inner wall of glass tubes. This phenomenon is not accompanied by changes in the quenching index. However, the effectiveness of measurement dropped and the relative contribution of the spectra of the two radionuclides changed with the time following sample preparation. The said effects were removed by adding 0.4% silicon dioxide (Cab-O-Sil M5, Serva) to the liquid scintillator.

  13. Multiple DNA adducts in lymphocytes of smokers and nonsmokers determined by 32P-postlabeling analysis

    International Nuclear Information System (INIS)

    Identification of DNA adducts in peripheral lymphocytes could serve as a means of monitoring human exposure to potential genotoxic agents. In the study, DNA from peripheral lymphocytes of smokers and nonsmokers was examined for adducts by the P1 nuclease 32P-post-labeling technique. Thin layer chromatography (TLC) maps from both groups revealed multiple DNA adducts which ranged from no adducts for one individual to six adducts for a different individual. The total DNA adduct concentrations were approximately one adduct in 10 to the seventh-10 to the eighth power normal nucleotides. Comparison of the adduct TLC profiles revealed individual variation in both pattern and level of DNA adducts. The type and amount of adduct was not influenced by smoking history and remained unchanged in four out of six subjects who were resampled after a one month interval. One adduct detected in lymphocyte DNA co-migrated on TLC with an adduct derived by in vitro incubation of lymphocytes with benzo(a)pyrene (B(a)P). The 3H-nucloside values were consistent with values obtained by 32P-postlabeling of the same sample (correlation coefficient of 0.88). No relationship was apparent between the capacity of lymphocytes to form a (3H)-B(a)P-derived adduct in vitro and the concentration of the adduct, or total adducts present in untreated lymphocytes

  14. Intraperitoneal distribution of 32P-chromic phosphate suspension in the dog

    International Nuclear Information System (INIS)

    Intraperitoneal administration of radioactive chromic phosphate suspension is receiving renewed attention as a therapeutic treatment to limit metastatic dissemination of ovarian carcinoma. Our study utilized mongrel dogs to approximate the uptake and distribution of 3.0 millicuries 32P-chromic phosphate suspension administered intraperitoneally (IP). Lymph nodes, omentum, retroperitoneum, peritoneum, diaphragm, abdominal wall muscle, pleura, spleen, liver, kidneys, lung, small intestine, and blood were sampled for liquid scintillation counting and autoradiography. Whole blood showed the least activity (1800 cpm/100 lambda at day one, declining to 2800 cpm/100 lambda by day 16). Omentum and diaphragm maintained the greatest concentrations (183 x 106 dpm/g and 4 x 106 dpm/g respectively). These initial high values were 100 times greater than the highest values found for the small intestine, abdominal wall muscle, mediastinal and retroperitoneal lymph nodes and pleura. The peritoneum increased in specific activity until day three (5.9 x 106 dpm/g) and then rapidly declined. Our results show that following IP administration to the dog, 32P suspension is associated with the serous membranes of the peritoneal cavity (most notably omentum, diaphragm, peritoneum, and retroperitoneum). This distribution could be valuable in adjuvant tumor therapy since serosal surfaces of the peritoneum (both visceral and parietal) and the omentum are the most common sites of tumor metastases associated with ovarian carcinoma

  15. Histological study of the early stage of 32P-induced experimental osteosarcoma

    International Nuclear Information System (INIS)

    32P radioisotope as an orthophosphate solution was injected intraperitoneally into C.F. Wistar strain albino rats to induce primary osteosarcoma. To capture the early stage of tumor formation, bone scintigraphy employing technetium-99m ethane-1-hydroxy-1,1-diphosphonate and soft radiography were conducted from week 16 after the beginning of 32P administration. The histological findings were compared at the stages when both the soft radiogram and bone scintigram showed no abnormalities (Group A), the soft radiogram showed no abnormality but the bone scintigram revealed abnormal deposition (Group B), similar findings to those in Group B were obtained but 2 weeks later (Group C), and both the soft radiogram and bone scintigram were positive (Group D). The histological picture before osteosarcoma formation demonstrated a marked reduction of bone marrow tissue, many irregular bone trabeculae in the metaphysis due to abnormal endochondral ossification, and zonal obliteration of the medullary cavity in the diaphysis. The histological findings at the ultra-early stage of osteosarcoma formation included irregularity in the growing cartilage zone and highly atypical osteoblast-like cells among the irregular trabeculae. Osteoid formation occurred 2 weeks later. In conclusion, we were able to observe the morphological changes of the osteosarcoma tissue at a very early stage of tumor formation. (author)

  16. Sampling system for pulsed signals. Study of the radioactive lifetimes of excited 32P1/2 and 32P3/2 states of Na, excited by a tunable dye laser

    International Nuclear Information System (INIS)

    A system for sampling and averaging repetitive signals in the order of nanoseconds is discussed. The system uses as storage memory a multichannel analyzer operating in multi scaling mode. This instrument is employed for the measurement of atomic level lifetimes using a dye laser to excite the atoms and is applied to the study of lifetimes of the 32P1/2 and 32P3/2 states of sodium. (Author) 32 refs

  17. Dissolved Organic Carbon 14C in Southern Nevada Groundwater and Implications for Groundwater Travel Times

    Energy Technology Data Exchange (ETDEWEB)

    Hershey, Ronald L.; Fereday, Wyall; Thomas, James M

    2016-08-01

    Dissolved inorganic carbon (DIC) carbon-14 (14C) ages must be corrected for complex chemical and physical reactions and processes that change the amount of 14C in groundwater as it flows from recharge to downgradient areas. Because of these reactions, DIC 14C can produce unrealistically old ages and long groundwater travel times that may, or may not, agree with travel times estimated by other methods. Dissolved organic carbon (DOC) 14C ages are often younger than DIC 14C ages because there are few chemical reactions or physical processes that change the amount of DOC 14C in groundwater. However, there are several issues that create uncertainty in DOC 14C groundwater ages including limited knowledge of the initial (A0) DOC 14C in groundwater recharge and potential changes in DOC composition as water moves through an aquifer. This study examines these issues by quantifying A0 DOC 14C in recharge areas of southern Nevada groundwater flow systems and by evaluating changes in DOC composition as water flows from recharge areas to downgradient areas. The effect of these processes on DOC 14C groundwater ages is evaluated and DOC and DIC 14C ages are then compared along several southern Nevada groundwater flow paths. Twenty-seven groundwater samples were collected from springs and wells in southern Nevada in upgradient, midgradient, and downgradient locations. DOC 14C for upgradient samples ranged from 96 to 120 percent modern carbon (pmc) with an average of 106 pmc, verifying modern DOC 14C ages in recharge areas, which decreases uncertainty in DOC 14C A0 values, groundwater ages, and travel times. The HPLC spectra of groundwater along a flow path in the Spring Mountains show the same general pattern indicating that the DOC compound composition does not change along this flow path. Although DOC concentration decreases from recharge-area to downgradient groundwater, the organic compounds are similar, indicating that DOC 14C is unaffected by other processes such as microbial

  18. Reviewing the Mid-First Millennium BC {sup 14}C 'warp' using {sup 14}C/bristlecone pine data

    Energy Technology Data Exchange (ETDEWEB)

    Taylor, R.E., E-mail: retaylor@ucr.edu [Department of Anthropology, University of California, Riverside, Riverside, CA (United States); Cotsen Institute of Archaeology, University of California, Los Angeles, CA (United States); Keck Carbon Cycle Accelerator Mass Spectrometry Laboratory, University of California, Irvine, CA (United States); Southon, John [Keck Carbon Cycle Accelerator Mass Spectrometry Laboratory, University of California, Irvine, CA (United States)

    2013-01-15

    AMS-based {sup 14}C measurements have been obtained on 53 dendrochronologically-dated Bristlecone pine (Pinus longaeva) wood samples in decadal increments spanning 2300-2750 cal BP with particular interest focused on the decades centered on 2405 cal BP and 2625 cal BP. In general, there is overall agreement with the current IntCal04/09 consensus calibration curve for this period. For the 2400-2410 cal BP interval, our Bristlecone-based {sup 14}C value is consistent with the {sup 14}C value obtained by Belfast on Irish oak for that decade but not on German oak values obtained by Seattle. Our {sup 14}C value for the 2620-2630 cal BP interval is consistent with the German oak (Heidelberg)-based {sup 14}C decadal value. The {sup 10}Be-based reconstruction of {sup 14}C variations over the 2620-2630 cal BP interval also supports the Heidelberg data although clearly additional clarifications are required before the current tree ring-based {sup 14}C and ice core-based {sup 10}Be data for this interval can be accurately interpreted and valid inferences obtained.

  19. 32P-adduct assay: Comparative recoveries of structurally diverse DNA adducts in the various enhancement procedures

    International Nuclear Information System (INIS)

    A (32)P-adduct assay for the measurement of low levels (1 adduct per 10(sup 7) nucleotides) of binding of carcinogens to DNA has been reported previously. In this procedure, DNA is enzymatically hydrolyzed to 3'-monophosphates of normal nucleosides and adducts, which are 5'-(32)P-labeled by T4 polynucleotide kinase and (lambda(32)P)ATP. Labeled adducts are resolved by TLC. Enrichment of adducts by extraction in 1-butanol or digestion with nuclease P1 prior to (32)P-labeling, however, increased the sensitivity of detection for many adducts to a level of 1 per 10(sup 9-10) nucleotides, although adduct recovery particularly in the latter assay depended on the chemical nature of adducts. The observation that chemical structure of an adduct may be detrimental in its recovery in the enzyme- and extraction-mediated enrichment procedures may serve as a probe in the structural characterization of adducts of unknown carcinogens

  20. Co-isolation of in vivo 32P-labeled specific transcripts and DNA without phenol extraction of nuclease digestion

    International Nuclear Information System (INIS)

    A method is described for isolation and quantitation of specific intact transcripts, for which a hybridization probe is available, from 32P-labeled bacterial cells. The RNA is extracted in the absence of R Nase activity by incorporating an inert, physically removable R Nase inhibitor throughout the spheroplasting, cell lysis, and pronase digestion steps. [/sup 32/P]RNA is separated from [32P]DNA, without recourse to phenol extraction of DNase treatment, on a Cs2SO/sub 4-/HCONH2 step gradient in which the precipitated RNA forms a sharp band. Specific transcripts are purified from [32P]RNA by physical separation of the transcript and hybridization probe using gel-exclusion chromatography. The gentleness of this technique enables the co-isolation of DNA and can facilitate the analysis of covalently joined RNA-DNA replication intermediates

  1. Preparation of /sup 14/C-labelled AMP, ADP and ATP from adenine-8-/sup 14/C by using Brevibacterium ammoniagenes

    Energy Technology Data Exchange (ETDEWEB)

    Pande, V.N. (Bhabha Atomic Research Centre, Bombay (India). Biochemistry and Food Technology Div.)

    1985-04-01

    High radiochemical yields of /sup 14/C-labelled adenine nucleotides (AMP, 4.6%, ADP, 15.5% and ATP 59.5%) could be obtained by growing the cells of Brevibacterium ammoniagenes in the presence of /sup 14/C-adenine. The specific radioactivity of the adenine nucleotides almost reached that of /sup 14/C-adenine indicating negligible dilution of the label. The procedure is convenient and especially suited for commercial preparation of the radiolabelled nucleotides directly from labelled adenine. Preliminary results indicate that the organism could also be used for the preparation of radiolabelled guanine nucleotides.

  2. Metabolism of ( sup 14 C)cholesterol to C-20 isomeric ( sup 14 C)pregn-5-ene-3,20-diols in the tobacco hornworm, Manduca sexta

    Energy Technology Data Exchange (ETDEWEB)

    Lozano, R.; Thompson, M.J.; Svoboda, J.A.; Lusby, W.R.; Wilzer, K.R. Jr. (Insect and Nematode Hormone Laboratory, Beltsville, MD (USA))

    1989-03-01

    After injection into male and female fifth-instar larvae of Manduca sexta, ({sup 14}C)cholesterol was converted to C21 steroids, ({sup 14}C)pregn-5-ene-3 beta,20-diols. These metabolites were isolated from 8-day-old pupae and were identified by TLC, HPLC, and GC-MS as the C-20 isomers of pregnene-3 beta,20-diol. They also were isolated from male and female meconium fluid (of 16-day-old pupae) following injection of ({sup 14}C)cholesterol into 14-day-old pupae.

  3. Formation and bio release of bound residues of [14 C]-lindane and [14 C]-parathion in two Brazilian soils

    International Nuclear Information System (INIS)

    This work studied the extractable and bound residues formation of 14 C-lindane and 14 C-parathion immediately after application and after 3 months of interaction of the pesticides with the soils. Metabolism, bio release, and the possible bioavailability of bound residues were studied by employing bio meter flasks which allowed a relative comparison of the behaviour of the two different 14 C-pesticides, by a balance of the applied or present radiocarbon in the soils after the bio tests. (author)

  4. Evaluation of 14C abundance in soil respiration using accelerator mass spectrometry

    International Nuclear Information System (INIS)

    To clarify the behavior of 14C in terrestrial ecosystems, 14C abundance in soil respiration was evaluated in an urban forest with a new method involving a closed chamber technique and 14C measurement by accelerator mass spectrometry (AMS). Soil respiration had a higher Δ14C than the contemporary atmosphere. This indicates that a significant portion of soil respiration is derived from the decomposition of soil organic matter enriched in 14C by atmospheric nuclear weapons tests, with a notable time lag between atmospheric 14C addition and re-emission from soil. On the other hand, δ14C in soil respiration demonstrated that 14C abundance ratio itself in soil-respired CO2 is not always high compared with that in atmospheric CO2 because of the isotope fractionation during plant photosynthesis and microbial decomposition of soil organic matter. The Δ14C in soil respiration was slightly lower in August than in March, suggesting a relatively high contribution of plant root respiration and decomposition of newly accumulated and/or 14C-depleted soil organic matter to the total soil respiration in August

  5. A new 14C calibration data set for the last deglaciation based on marine varves

    Energy Technology Data Exchange (ETDEWEB)

    Hughen, K A; Kashgarian, M; Lehman, S J; Overpeck, J T; Peterson, L C; Southon, J R

    1999-02-22

    Varved sediments of the tropical Cariaco basin provide a new {sup 14}C calibration data set for the period of deglaciation (10,000 to 14,500 years before present: 10-14.5 cal ka BP). Independent evaluations of the Cariasco Basin calendar and {sup 14}C chronologies were based on the agreement of varve ages with the GISP2 ice core layer chronology for similar high-resolution paleoclimate records, in addition to {sup 14}C age agreement with terrestrial {sup 14}C dates, even during large climatic changes. These assessments indicate that the Cariaco Basin {sup 14}C reservoir age remained stable throughout the Younger Dryas and late Alleroed climatic events and that the varve and {sup 14}C chronologies provide an accurate alternative to existing calibrations based on coral U/Th dates. The Cariaco Basin calibration generally agrees with coral-derived calibrations but is more continuous and resolves century-scale details of {sup 14}C change not seen in the coral records. {sup 14}C plateaus can be identified at 9.6, 11.4, and 11.7 {sup 14}C ka BP, in addition to a large, sloping plateau during the Younger Dryas ({approximately}10 to 11 {sup 14}C ka BP). Accounting for features such as these is crucial to determining the relative timing and rates of change during abrupt global climate changes of the last deglaciation.

  6. In vitro estimation of rumen protein degradability using 35S to label the bacterial mass

    International Nuclear Information System (INIS)

    An experiment was carried out in order to simplify a previously developed 15N-method for in vitro estimation of rumen protein degradability. Casein (Cas), whole soybeans (Sb) heated at 120oC for 20 min (SbTherm) and sunflower (Sfl) were incubated at 39oC for 4 hours in a water bathshaker with the following media: McDougall's buffer, strained and enriched with particle associated bacteria rumen fluid (2:1), rapidly (maltose, sucrose, glucose) and more slowly (pectin, soluble starch) degradable carbohydrates with final concentration of 815 mg/100 ml and 21.7 μCi/100 ml of35S (from Na235SO4). After the incubation had been ceased, a bacterial fraction was isolated through differential centrifugation and specific activity of bacterial (Bac) and high speed total solids (TS) nitrogen was measured. The ratio was used to calculate bacterial mass in TS and through the Kjeldahl nitrogen concentration in TS - the net bacterial growth (against control vessels without protein). The level of ammonia-N in the supernate after blank correction was used to find the ammonia-N released from protein degradation. The data showed that the rate (and extend) of degradation for the Cas (as a standard protein) was lower compared to those obtained through the 15N-method but it was higher than the rate derived through another in vitro method. The Cas equivalent of the Sb was higher than the figure we found in a previous experiment with solvent extracted soybean meal suggesting that the 35S-method underestimated the degradability of the Cas. After being tested on a wider range of foodstuffs, the proposed 35S-method might be considered as an alternative procedure which is less laborous than the 15N-method. (author)

  7. New metabolic labelling medium for Trichomonas vaginalis and Tritrichomonas foetus using 35S methionine

    Energy Technology Data Exchange (ETDEWEB)

    Torian, B.E.; Kenny, G.E.

    1986-04-01

    A metabolic labelling medium was devised for Trichomonas vaginalis and Tritrichomonas foetus utilizing 35S methionine. T. vaginalis cultured for 24h in the medium took up approximately 27% of the available label and increased greater than two fold in number. Counts per microgram of protein were 32,555 +/- 10% between different strains or identical strains in different labelling runs. T. foetus took up approximately 5% of the available label and increased greater than two fold in 24h. This resulted in specific labelling of 12,704 cpm/ug protein +/- 10% between different runs with the same strain.

  8. Diffusion of sulfur 35S in β-Ni3S2

    International Nuclear Information System (INIS)

    The diffusion of 35S radioisotope in β-Ni3S2 polycrystals was studied at temperatures ranging from 848 to 893 K and at sulfur vapour pressure (5.6 x 10-6 - 3.2 x 10-4) Pa. The autoradiography and the tracer sectioning method were used. It was found that the bulk diffusion is the main process of sulfur transport. The activation energy of the diffusion equals (190±10) kJmol-1. Under the conditions used in the experiments the dominant anionic point defects are single-ionized vacancies and quasi-free electrons. (author)

  9. Comparison of 32P therapy and sequential hemibody irradiation (HBI) for bony metastases as methods of whole body irradiation

    International Nuclear Information System (INIS)

    We report a retrospective study of 15 patients with prostate carcinoma and diffuse bone metastases treated with sodium 32P for palliation of pain at Downstate Medical Center and Kings County Hospital from 1973 to 1978. The response rates, duration of response, and toxicities are compared with those of other series of patients treated with 32P and with sequential hemibody irradiation. The response rates and duration of response are similar with both modalities ranging from 58 to 95% with a duration of 3.3 to 6 months with 32P and from 75 to 86% with a median duration of 5.5 months with hemibody irradiation. There are significant differences in the patterns of response and in the toxicities of the two treatment methods. Both methods cause significant bone marrow depression. Acute radiation syndrome, radiation pneumonitis, and alopecia are seen with sequential hemibody irradiation and not with 32P, but their incidence can be reduced by careful treatment planning. Hemibody irradiation can provide pain relief within 24 to 48 h, while 32P may produce an initial exacerbation of pain. Lower hemibody irradiation alone is less toxic than either upper hemibody irradiation or 32P treatment

  10. Comparison of /sup 32/P therapy and sequential hemibody irradiation (HBI) for bony metastases as methods of whole body irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Aziz, H.; Choi, K.; Sohn, C.; Yaes, R.; Rotman, M.

    1986-06-01

    We report a retrospective study of 15 patients with prostate carcinoma and diffuse bone metastases treated with sodium /sup 32/P for palliation of pain at Downstate Medical Center and Kings County Hospital from 1973 to 1978. The response rates, duration of response, and toxicities are compared with those of other series of patients treated with /sup 32/P and with sequential hemibody irradiation. The response rates and duration of response are similar with both modalities ranging from 58 to 95% with a duration of 3.3 to 6 months with /sup 32/P and from 75 to 86% with a median duration of 5.5 months with hemibody irradiation. There are significant differences in the patterns of response and in the toxicities of the two treatment methods. Both methods cause significant bone marrow depression. Acute radiation syndrome, radiation pneumonitis, and alopecia are seen with sequential hemibody irradiation and not with /sup 32/P, but their incidence can be reduced by careful treatment planning. Hemibody irradiation can provide pain relief within 24 to 48 h, while /sup 32/P may produce an initial exacerbation of pain. Lower hemibody irradiation alone is less toxic than either upper hemibody irradiation or /sup 32/P treatment.

  11. Phosphorus Use Efficiency by Brazilian Common Bean Genotypes Assessed by the 32P Dilution Technique

    International Nuclear Information System (INIS)

    The objectives of this work were to identify the most efficient common bean (Phaseolus vulgaris L.) genotypes on phosphorus (P) utilization, and verify if P from the seed affects the classification of common bean genotypes on P uptake efficiency when the 32P isotopic dilution technique is used. The experiment was conducted in a greenhouse, and plants were grown in pots with surface samples of a dystrophic Typic Haplustox. The treatments consisted of 50 common bean genotypes and two standard plant species, efficient or inefficient in P uptake. The results were assessed through correlation and cluster analysis (multivariate). Sangue de Boi, Rosinha, Thayu, Grafite, Horizonte, Pioneiro and Jalo Precoce common bean genotypes were the most efficient on P uptake, and Carioca 80, CNF 10, Perola, IAPAR 31, Roxao EEP, Apore, Pioneiro, Pontal, Timbo and Ruda were the most efficient in P utilization. The P derived from seed influences the identification of common bean genotypes for P uptake efficiency. (author)

  12. Phosphorus Use Efficiency by Brazilian Upland Rice Genotypes Evaluated by the 32P Dilution Technique

    International Nuclear Information System (INIS)

    The objectives of this work were to identify the most efficient upland rice genotypes in phosphorus (P) utilization, and to verify if P from the seed affects the classification of upland rice genotypes on P uptake efficiency. The experiment was conducted in a greenhouse of the Center for Nuclear Energy in Agriculture (CENA/USP), Piracicaba, Sao Paulo, Brazil, using the 32P isotope technique, and plants were grown in pots with samples of dystrophic Typic Haplustox (Oxisol). The experimental design was completely randomized with four replications. The treatments consisted of 47 upland rice genotypes and two standard plant species, efficient or inefficient in P uptake. The results were assessed through correlation and cluster analysis (multivariate). The Carisma upland rice genotype was the most efficient in P uptake, and Caripuna was the most efficient on P utilization. The P derived from seed does not influence the identification of upland rice genotypes in P uptake efficiency. (author)

  13. Separation of phosphorous by liquid-liquid extraction for the measurement of 32P

    International Nuclear Information System (INIS)

    Phosphorous containing radioisotope waste was separated and determined by liquid-liquid extraction method through liquid scintillation counter (LSC). In this process, ammonium phosphate was converted to phosphomolybdate (PMo) by the reaction of ammonium molybdate (Mo) in HCl solution (0.02 M) and maximum UV/VIS absorbance (λmax) 218 nm was observed. The PMo solution was extracted with TOA (Tri-n-Octylamine)/xylene mixture and λmax 290 nm was found for this organic layer. Absorbance of aqueous and organic layer was linear through concentration. The impurities such as Co, Cr, Gd, etc. remain in aqueous layer by treating with Mo which was determined by ICP-AES and AAS. The quenching correction curve for 32P was calculated using LSC results. No counting change was observed as the volume of quenchers increased. The recovery was 98% and 81% for the extraction and separation process from the test using H332PO4 as standard tracer. (author)

  14. Design and construction of a prototype for the obtention of 32 P

    International Nuclear Information System (INIS)

    In the National Institute of Nuclear Research (ININ) it was designed, built and proved a prototype to obtain 32P in form of H332PO4, starting from irradiated Sα. The beginning of the prototype it is based on a distillation system in dry of the Sα in nitrogen atmosphere, and in the formation of the ion 32PO43- in acid solution. Due to the handling of radioactive material during the process, the prototype is inside a hot cell and it has a cylindrical oven that opens up lengthwise to the half, with controller of temperature and with a system of empty air for to transport reagents and products. The air-vacuum system is provided of filters and traps. The tests showed a recovery from 14 to 15% of the activity obtained during the irradiation. (Author)

  15. {sup 14}C emission from Swedish nuclear power plants and its effect on the {sup 14}C levels in the environment

    Energy Technology Data Exchange (ETDEWEB)

    Stenstroem, K.; Erlandsson, Bengt; Hellborg, R.; Kiisk, M.; Persson, Per [Lund Univ. (Sweden). Dept. of Nuclear Physics; Mattsson, Soeren; Thornberg, C. [Lund Univ., Malmoe (Sweden). Dept. of Radiation Physics; Skog, G. [Lund Univ. (Sweden). Dept. of Quaternary Geology

    2000-02-15

    The radionuclide {sup 14}C is produced in all types of nuclear reactors mainly by neutron induced reactions in oxygen ({sup 17}O), nitrogen ({sup 14}N) and carbon ({sup 13}C). Part of the {sup 14}C created is continuously released during normal operation as airborne effluents in various chemical forms (such as CO{sub 2}, CO and hydrocarbons) to the surroundings. Because of the biological importance of carbon and the long physical half-life of {sup 14}C, it is of interest to measure the releases and their incorporation into living material. The {sup 14}C activity concentrations in annual tree rings and air around two Swedish nuclear power plants (Barsebaeck and Forsmark) as well as the background {sup 14}C activity levels from two reference sites in southern Sweden during 1973-1996 are presented in this report. In order to verify the reliability of the method some investigations have been conducted at two foreign nuclear sites, Sellafield fuel reprocessing plant in England, and Pickering nuclear generating station in Canada, where the releases of {sup 14}C are known to be substantial. Furthermore, results from some measurements in the vicinity of Paldiski submarine training centre in Estonia are presented. The results of the {sup 14}C measurements of air, vegetation and annual tree rings around the two Swedish nuclear power plants show very low enhancements of {sup 14}C, if at all above the uncertainty of the measurements. Even if the accuracy of the measurements of the annual tree rings is rather good (1-2%) the contribution of {sup 14}C from the reactors to the environment is so small that it is difficult to separate it from the prevailing background levels of {sup 14}C . This is the case for all sampling procedures: in air and vegetation as well as in annual tree rings. Only on a few occasions an actual increase is observed. However, although the calculations suffer from rather large uncertainties, the calculated release rate from Barsebaeck is in fair agreement

  16. Effect of dead carbon on the 14C dating of the speleothem

    Institute of Scientific and Technical Information of China (English)

    CAI Yanjun; Warren Beck; PENG Zicheng; ZHANG Zhaofeng

    2005-01-01

    Based on the comparison of dating results among high-precision TIMS U-series and AMS 14C as well as the published 14C dating results and their band counting ages (i.e. calendar ages), this paper discusses the effect of dead carbon on the speleothem 14C dating. The result shows that the fraction of incorporated dead carbon during the formation of speleothem varies. The change in the fraction of dead carbon would result in big deviation in the 14C age of the speleothem. It is indispensable to take the dead carbon into consideration when dating the speleothem using the 14C method or studying the atmospheric 14C concentration during the past with the speleothem.

  17. 32P analysis of DNA adducts in tissues of benzene-treated rats

    International Nuclear Information System (INIS)

    Solid tumors have been reported in the Zymbal gland, oral and nasal cavities, liver, and mammary gland of Sprague-Dawley rats following chronic, high-dose administration of benzene. The carcinogenic activity of benzene is thought to be caused by activation to toxic metabolites that can interact with DNA, forming covalent adducts. A nuclease P1-enhanced 32P-postlabeling assay, having a sensitivity limit of 1 adduct in 10(9-10) DNA nucleotides, was found suitable for measuring aromatic DNA adducts derived in vitro from catechol, benzenetriol (BT), phenol, hydroquinone (HQ), and benzoquinone (BQ), potential metabolites of benzene. When DNA specimens isolated from tissues of female Sprague-Dawley rats at 24 hr after an oral gavage dose of 200 to 500 mg/kg, 5 days/week, in olive oil (3 mL/kg) for 1 day, 1 week, 5 weeks, and 10 weeks were analyzed by the 32P-postlabeling procedure, no aromatic adducts were detected unequivocally with DNA samples of liver, kidney, bone marrow, and mammary gland. With Zymbal gland DNA, three weak spots at levels totaling four lesions per 10(9) DNA nucleotides were seen only after 10 weeks of treatment, and these adducts did not correspond chromatographically to major adducts in vitro from the above specified compounds. Consequently, this finding requires confirmatory experiments. This distinct adduct pattern may relate to tumor induction in this organ following benzene administration. Our results also indicate that DNA adducts derived from catechol, BT, phenol, HQ, and BQ are either not formed in vivo with benzene or formed at levels below the detection limit of 1 adduct per 10(9-10) DNA nucleotides

  18. Effect of fasting on 32P translocations in pre-labelled pancreatic islets

    International Nuclear Information System (INIS)

    The rapid, short-lived efflux of inorganic 32P-orthophosphate that occurs when pre-labelled pancreatic islets are exposed to nutrient insulin secretagogues (the ''phosphate flush'') has been proposed to reflect some early step in β-cell secretory activation. In the present study, glucose-initiated phosphate efflux was studied during fasting.Pancreatic islets were isolated from fed and 48-h fasted rats by collagenase digestion. After pre-labelling with 32P-orthophosphate and basal perifusion with 0.5 mg/ml glucose, tissue analyses disclosed similar stores of radioactivity in the two groups of islets. Stimulatory perfusion with glucose at this time failed to promote insulin release from islets which had been secured from fasted donors although the ''phosphate flush'' was preserved. However, the characteristics of phosphate efflux were altered. Maximal glucose-induced phosphate release was greater with islets from fasted animals whereas phosphate release in response to low level stimulation with glucose was diminished. Accordingly, the dose-response curve for glucose-initiated phosphate efflux in islets from fasted rats was displaced to the right and compatible with a decreased sensitivity to glucose at the activation site for the ''phosphate flush.'' Thus, while glucose is unable to enhance insulin release in vitro after fasting, glucose still elicits increased phosphate efflux. However, the phenomenon appears to be attended by an impaired responsiveness to activation by glucose, supporting the contention that some early step in the sequence of stimulus secretion coupling in the β-cell may be obtunded after food deprivation. (author)

  19. Bound residues of 14C-chlorfenvinphos in winter rape and soil

    International Nuclear Information System (INIS)

    The binding properties of chlorfenvinphos were studied by application of 14C-chlorfenvinphos to the leaves and stems of winter rape and two loamy sand soils of different organic matter content. After application of vinyl-14C-chlorfenvinphos to the plants at a dosage of 0.3 mg/plant, no bound radioactivity was detected either in the flowers and siliques or in the roots. In the leaves and/or stems, the bound 14C-residues, expressed as chlorfenvinphos, ranged from 0.02 μg/g one hour after the treatment to 0.18 μg/g at harvest. Repeated treatment applied to the plants 9 days after the first application caused no increase of the bound residue concentration. Various treatments of stem-bound 14C with alkali and acid led to release of some radioactivity. When vinyl-14C-chlorfenvinphos was applied to the soils, the bound 14C-residues increased and the extractable 14C-residues decreased with time, particularly in the soil of higher organic matter content. After 114 days, the bound 14C-residues, expressed as percentage of the applied 14C, amounted to 13.7% in the soil of higher and 11.2% in the soil of lower organic matter content. When soil was treated with ring-14C-chlorfenvinphos, the bound and extractable 14C-residues were somewhat higher than those determined for vinyl label. Experiments suggested that binding was related to the activity of soil microorganisms since soil sterilization resulted in a reduction of bound 14C-residues by 80% (vinyl label) and 79% (ring label). (author)

  20. Effect of high temperature stress on photosynthesis and partitioning of 14C in Indian mustard

    International Nuclear Information System (INIS)

    The influence of high temperature stress on 14Co2 assimilation and partitioning of 14C by photosynthetically active parts of Indian mustard is investigated. It is observed that heat stressed plants have low rates of 14Co2 assimilation which leads to low rates of 14C export from source organs. Heat stress is also found to inhibit translocation of 14C-assimilates into sink organs. (M.G.B.). 21 refs., 4 figs

  1. Fate of 14C-labeled microbial products derived from nitrifying bacteria in autotrophic nitrifying biofilms

    OpenAIRE

    Okabe, Satoshi; Kindaichi, Tomonori; Ito, Tsukasa

    2005-01-01

    The cross-feeding of microbial products derived from 14C-labeled nitrifying bacteria to heterotrophic bacteria coexisting in an autotrophic nitrifying biofilm was quantitatively analyzed by using microautoradiography combined with fluorescence in situ hybridization (MAR-FISH). After only nitrifying bacteria were labeled with [14C] bicarbonate, biofilm samples were incubated with and without NH4+ as a sole energy source for 10 days. The transfer of 14C originally incorporated into nitrifying b...

  2. Fate of 14C-Labeled Microbial Products Derived from Nitrifying Bacteria in Autotrophic Nitrifying Biofilms

    OpenAIRE

    Okabe, Satoshi; Kindaichi, Tomonori; Ito, Tsukasa

    2005-01-01

    The cross-feeding of microbial products derived from 14C-labeled nitrifying bacteria to heterotrophic bacteria coexisting in an autotrophic nitrifying biofilm was quantitatively analyzed by using microautoradiography combined with fluorescence in situ hybridization (MAR-FISH). After only nitrifying bacteria were labeled with [14C] bicarbonate, biofilm samples were incubated with and without NH4+ as a sole energy source for 10 days. The transfer of 14C originally incorporated into nitrifying b...

  3. Using 10Be records to identify possible 14C calibration uncertainties during the Holocene

    Science.gov (United States)

    Raimund, Muscheler

    2010-05-01

    The Intcal04 and Intcal09 radiocarbon calibration records are based on multiple tree-ring 14C data sets for Holocene period (Reimer et al. 2004, Reimer et al. 2009). While the dendrochronolgical dating of the trees is supposedly free of errors there are differences between various 14C data sets that underlie the 14C calibration curve. Due to lack of knowledge about the reasons for the differences the Intcal04/09 calibration curves provide a smoothed average of the underlying 14C records. Therefore, problems in one or several of the underlying 14C records would translate directly into errors in the 14C age calibration. Additional knowledge about expected variations in the 14C production rate could help to improve the calibration record since it would allow us to assess how well the different 14C records represent the atmospheric 14C concentration. I propose that 10Be records could be used as additional criteria to chose which of the published 14C records should be preferred (or given stronger weight) for the construction of the calibration curve. Alternatively, 10Be records could point to periods where 14C data should be re-measured in order to improve the calibration curve. I will show for some case studies that the 10Be records from the Greenland ice cores (Muscheler et al. 2004, Vonmoos et al. 2006) indeed provide useful information to scrutinise the Intcal04/09 calibration curve, which could help to improve the 14C calibration curve during the Holocene. Especially shorter-term changes are strongly dampened in the Intcal04/09 calibration record. However, 10Be and some 14C records do exhibit more variability as compared to the calibration record. Therefore, the combined 10Be/14C approach could add confidence that these should be reflected in the 14C calibration record. References: Muscheler, R., Beer, J. et al., 2004. Changes in the carbon cycle during the last deglaciation as indicated by the comparison of 10Be and 14C records. Earth and Planetary Science Letters

  4. Photorespiratory CO2 release from l-[U-14C]serine in tomato leaves

    International Nuclear Information System (INIS)

    14CO2 release from L-[U-14C]serine in the illuminated tomato leaf was investigated. Exogenously added [1-14C] and [2-14C]glycine were metabolized in the glycolate pathway and 14CO2 was evolved at a low CO2 concentration from [2-14C]glycine in a similar manner to that from L-[U-14C]serine (Yamauchi and Yamada, Soil Sci. Plant Nutr., 26, 191-204 (1980)). α-Hydroxy-2-pyridinemethanesulfonic acid and isonicotinic acid hydrazide increased the [14C]glycolate and [14C]glycine accumulations, respectively, in leaves fed L-[U-14C]serine at a low CO2 concentration with a corresponding decrease in 14CO2 evolution. This may indicate that the carbon of serine was recycled back into the Calvin cycle and then incorporated into the glycolate pathway. The 14CO2 release from L-[U-14C] serine increased at high light intensity and high temperature. The contribution of CO2 release from serine to photorespiration is discussed. (author)

  5. In situ produced 14C by cosmic ray muons in ablating Antarctic ice

    International Nuclear Information System (INIS)

    Samples of a core (52 m) of ablating Antarctic ice were analyzed for 14CO and 14CO2 by accelerator mass spectrometry. The data were compared with a 14C in situ production model that includes muon capture in addition to oxygen spallation by neutrons. The analysis reveals significant in situ 14C at depths below 10 m, which we attribute to 14C production by cosmic ray muons. The age of the ice was determined as 9.3 ± 0.4 14C ka BP

  6. Straw 14C Decomposition and Distribution in Humus Fractions as Influenced by Soil Moisture Regimes

    Institute of Scientific and Technical Information of China (English)

    WANGZHIMING; ZHUPEILI; 等

    1999-01-01

    14C-tracer technique and closed incubation method were used to study straw 14C decomposition and distribution in different fractions of newly fromed humus under different moisture regimes.Decomposition of straw 14C was faster during the initial days,and slower thereafter,Decay rate constants of straw 14C varied from 3.29×10-3d-1 to 7.06×10-3 d-1,After 112d incubation,the amount of straw 14C mineralized was 1.17-1.46 times greater in submerged soils than in upland soils.Of the soil residual 14C,9.08%-15.75% was present in humic acid(HA) and 31.01%-37.62% in fulvic acid(FA).Submerged condition favored the formation of HA,and HA/FA ratio of newly formed humus(labelled)was greater in submerged soils than in upland soils.Clay minerals affected the distribution of straw 14C in different humus fractions.Proportion of 14C present in HA to 14C remaining in soil was greater in Vertisol than in Ultisol.

  7. Localized defoliation stress and the movement of 14C-photoassimilates between tillers of Carex bigelowii

    International Nuclear Information System (INIS)

    14C was used to study how localized defoliation affects the pattern and the degree of photoassimilate translocation between interconnected, and physiologically integrated tiller generations of the rhizomatous sedge Carex bigelowii, and important forage species in Icelandic rangelands. The duration of increased 14C subsidy to repetedly defoliated tillers was also studied. 14C-translocation from a labelled tiller to a daughter tiller in control plants was fastest during the first day after labelling, when most of the 14C was translocated. When daughter tillers were defoliated, the amount of 14C translocated into them from labelled parent tillers was increased six-fold and the rate of translocation was still high 4 d after labelling. The greatest amounts of 14C were recovered in green leaves and rhizomes of daughter tillers, but the highest concentration was found in roots. In control plants, the amount of 14C-subsidy to young tillers was inversely related to their size, larger tillers tending to be more photosynthetically independent. However, when the young tillers were defoliated, the 14C-subsidy increased to all size classes. About 20% of the total 14C recovered 10 d after labelling had been exported from the labelled control tillers and translocated both distally into younger tiller generations and proximally into much older tiller generations with only below-ground organs remaining alive. Undefoliated tillers increased their 14C-support to defoliated neighbours (daughter or parent tiller) by increasing the proportion of 14C exported and without changing this basic pattern of direction of 14C-translocation. A defoliated tiller could not increase its subsidy of 14C to its defoliated daughter tiller. When young tillers were defoliated repeatedly, at 10-12 d intervals, their parent tillers subsidized them with increased amounts of 14C after a first and second defoliation, but not after a third defoliation. When the parent tillers were repeatedly defoliated

  8. Determination of surface dose rate of indigenous 32P patch brachytherapy source by experimental and Monte Carlo methods

    International Nuclear Information System (INIS)

    Isotope production and Application Division of Bhabha Atomic Research Center developed 32P patch sources for treatment of superficial tumors. Surface dose rate of a newly developed 32P patch source of nominal diameter 25 mm was measured experimentally using standard extrapolation ionization chamber and Gafchromic EBT film. Monte Carlo model of the 32P patch source along with the extrapolation chamber was also developed to estimate the surface dose rates from these sources. The surface dose rates to tissue (cGy/min) measured using extrapolation chamber and radiochromic films are 82.03±4.18 (k=2) and 79.13±2.53 (k=2) respectively. The two values of the surface dose rates measured using the two independent experimental methods are in good agreement to each other within a variation of 3.5%. The surface dose rate to tissue (cGy/min) estimated using the MCNP Monte Carlo code works out to be 77.78±1.16 (k=2). The maximum deviation between the surface dose rates to tissue obtained by Monte Carlo and the extrapolation chamber method is 5.2% whereas the difference between the surface dose rates obtained by radiochromic film measurement and the Monte Carlo simulation is 1.7%. The three values of the surface dose rates of the 32P patch source obtained by three independent methods are in good agreement to one another within the uncertainties associated with their measurements and calculation. This work has demonstrated that MCNP based electron transport simulations are accurate enough for determining the dosimetry parameters of the indigenously developed 32P patch sources for contact brachytherapy applications. - Highlights: • Surface dose rates of 25 mm nominal diameter newly developed 32P patch sources were measured experimentally using extrapolation chamber and Gafchromic EBT2 film. Monte Carlo model of the 32P patch source along with the extrapolation chamber was also developed. • The surface dose rates to tissue (cGy/min) measured using extrapolation chamber and

  9. Thick-target external-bremsstrahlung spectra of 147Pm and 35S β rays

    Science.gov (United States)

    Dhaliwal, A. S.; Powar, M. S.; Singh, M.

    1993-08-01

    External-bremsstrahlung spectra excited by soft β particles of 147Pm (Emaxβ=225 keV) and 35S (Emaxβ=167 keV) in targets of Al, Cu, Sn, and Pb have been studied. The experimental and theoretical results are compared in terms of the number of photons of energy k per m0c2 per unit photon yield to exclude the uncertainty in the source strength measurement and overcome the inherent inadequacy of the normalization procedure used by earlier workers. The results of present measurements for medium- and high-Z elements show better agreement with the theory of Tseng and Pratt [Phys. Rev. A 3, 1714 (1976)] than with Elwert's corrections [Ann. Phys. (N.Y.) 34, 78 (1939)] to the Bethe-Heitler theory [Proc. R. Soc. London Ser. A 14, 83 (1934)], particularly at the higher-energy ends. However, for low-Z elements, both theories are found to be adequate.

  10. Implants with 32P-foils for LDR-brachytherapy of benign stenosis in urology and gastroenterology

    International Nuclear Information System (INIS)

    For LDR-brachytherapy, a limited number of implant geometries and materials are available. To avoid wound healing related hyper-proliferation (stenosis, keloids) a novel radioactive foil system was developed based on beta emitting 32P, which can be easily integrated in existing implants such as urethral catheters or bile duct stents. As substrate material for these foils PEEK (polyetherethercetone) was chosen because of its radiation hardness during neutron activation of 32P. The activity was determined by liquid scintillation counting and gamma spectroscopy, dose distributions were measured with scintillation detectors and radiochromic films. The correlation between activity and dose was checked by Monte-Carlo-simulations (Geant4). Prototypes of the 32P-implants have shown in wash-out tests the required tightness for sealed radioactive sources. In animal tests on urethra and bile duct, the uncomplicated and save application of 32P-foils mounted on standard implants has been demonstrated, which is almost unchanged due to the simple radiation protection with plexiglass. This concept of radioactive implants with integrated 32P-foils could extend essentially the application possibilities of LDR-brachytherapy. (orig.)

  11. Benzene Synthesis for 14C Measurements and Evaluation of Uncertainty in Mollusk Shells

    International Nuclear Information System (INIS)

    This work describes the method and Instrumentation used by Environmental Isotopes laboratory of the CIEMAT Analytical Chemistry Laboratory (DIAE) for the synthesis of benzene from carbonates of mollusk shells and the liquid scintillation counting of 14C for radiocarbon dating in these samples. The usefulness of mollusk shells for 14C dating are considered. (Author) 15 refs

  12. 14C assimilate distribution and accumulation of hybrid spring wheat during fore-anthesis

    International Nuclear Information System (INIS)

    14C assimilate distribution and accumulation at fore-anthesis in various organs of hybrid spring wheat 901 and its parent Sh an 229 were studied by using 14C tracer techniques. The results showed that from fore-anthesis stage to filling stage, 14C assimilate distribution rate in leaves and sheath decreased by 23.1% and 7.8% respectively for 901, and decreased by 32.1% and 7.7% respectively for Sh an 229. 14C assimilate distribution rate in stems increased by 7.3% and 22.0% for 901 and Sh an 229 respectively. There was a certain accumulation of 14C assimilate at ear shell in both cultivars. From fore-anthesis stage to maturing stage the distribution rate in ear shell raised 12.2% for 901, and 8.7% for Shan 229. 14C assimilate distribution rate in flag leaf in both cultivars gradually reduced within 21 days after anthesis. There was a peak in radioactivity in flag leaf for 901 after 35 days of anthesis. The filling of Shan 229 was faster than that of 901. The radioactivity of 14C assimilate in grain for Shan 229 was higher than that of 901.4.5% of 14C assimilates labelled at fore -anthesis transported to seeds for 901, and 11.1% for Shan 229

  13. The synthesis of [methylenedioxy-[sup 14]C]paroxetine BRL 29060A

    Energy Technology Data Exchange (ETDEWEB)

    Lawrie, K.W.M.; Rustidge, D.C. (SmithKline Beecham Pharmaceuticals Research and Development, Harlow (United Kingdom))

    1993-01-01

    Paroxetine (1), BRL 29060A, a potent antidepressant, has been prepared radiolabelled with carbon-14 in the methylenedioxy group in 5 steps and 20.9% overall yield from [[sup 14]C]dibromomethane. Two alternative preparations of 3,4-[methylenedioxy-[sup 14]C]phenol are also described. (Author).

  14. Preparation of specifically labeled 14C-(lignin)- and 14C-(cellulose)-lignocelluloses and their decomposition by the microflora of soil

    International Nuclear Information System (INIS)

    Microbial decomposition of lignocellulose in soil was studied using radioisotope techniques. Natural lignocelluloses containing 14C in either their lignin or cellulose (glucan) components were prepared by feeding plants L-[U-14C]phenylalanine or D-[U-14C]glucose, respectively, through their cut stems. Detailed chemical and chromatographic characterization of labeled lignocelluloses from three hardwood and three softwood species showed that those labeled by the [14C]glucose incorporation method contained specifically labeled cellulosic components, whereas those labeled by the [14C]phenylalanine incorporation method contained specifically labeled lignin components. Microbial degradation of these differentially labeled lignocelluloses was followed by monitoring 14CO2 evolution from selected soil samples incubated with known amounts of radiolabeled lignocelluloses. The lignin components of the six woods were shown to be decomposed in soil 4 to 10 times more slowly than their cellulosic components. These rates of mineralization were comparable to the generalized patterns previously reported in the literature. The present technique, however, was thought to be simpler, more sensitive, and less prone to interference than methods previously available

  15. Rapid increase in cosmogenic 14C in AD 775 measured in New Zealand kauri trees indicates short-lived increase in 14C production spanning both hemispheres

    Science.gov (United States)

    Güttler, D.; Adolphi, F.; Beer, J.; Bleicher, N.; Boswijk, G.; Christl, M.; Hogg, A.; Palmer, J.; Vockenhuber, C.; Wacker, L.; Wunder, J.

    2015-02-01

    In 2012, Miyake et al. reported a sudden and strong increase of the atmospheric radiocarbon (14C) content in Japanese cedar trees of 1.2% between AD 774 and 775. While their findings were quickly confirmed by a German oak chronology for the Northern Hemisphere (NH), the question remained if the effect was seen in both hemispheres. Here we present the first annually resolved Southern Hemisphere (SH) 14C record spanning the interval AD 760-787, using New Zealand kauri (Agathis australis) chronology wood. An almost identical distinct increase compared to Northern Hemisphere data was observed, suggesting a cosmic event with globally uniform impact as a potential cause for the increase. Deploying a carbon cycle box model a worldwide averaged net 14C production of 2.2 ×108 14C atoms cm-2 was estimated, which is 3.7 times higher than the average annual 14C production. The immediate appearance of the event in tree rings on both hemispheres suggests a short duration event of significantly less than 1 yr.

  16. The release of 14C-chlorsulfuron bound residue by autoclavingmethod and its identification

    Institute of Scientific and Technical Information of China (English)

    1999-01-01

    When individual microorganisms were used torelease bound pesticide residues, it was ussually not take into fullaccountwhether the autoclaving method could lead to the releaseof bound residues. The soil containing bound14C-chlorsulfuron residues was treated with an autoclavein this study. The results reveal that the bound14C-chlorsulfuron residue can be released from the soilwhen treated with the autoclave and the release rate canbe remarkably enhanced by adding water into the soil whensubjected to such treatment. A TLC analysis showed that thereleased 14C-residue was one of the degraded products of14C-chlorsulfuron. After derivatization and analysis using theGC-MS, the released 14C-residue was tentatively identifiedas 2-amino-4-hydroxyl-6-methyl-1,3,5-triazine.

  17. Measuring techniques for environmental 3H, 14C and 222Rn by liquid scintillation counter

    International Nuclear Information System (INIS)

    Measuring techniques for environmental 3H, 14C and 222Rn with a liquid scintillation counter have been studied. 3H in environmental water was enriched by electrolysis and measured with a low background liquid scintillation counter. By this technique, 3H concentration of ground water, river water, sea water and rain water at Tokyo was founded to be 0.1 ∼ 2.5 Bq/1. 14C in taurine and ethyl-alcohol was measured directly liquid scintillation counter. By this 14C measuring, natural products, contain low level 14C, were distinguished from synthesised products contain no 14C. 222Rn in toluene extracted from environmental water or air was measured by scintillation pulse interval analysis method. By this technique, 222Rn was able to be measured under very low background counting rate, 0.03cpm, and high efficiency. (author)

  18. Effects of commercial processing procedures on 14C-pirimiphos-methyl residues in soybean oil

    International Nuclear Information System (INIS)

    Soybean plants were treated with two applications of 14C-pirimiphos-methyl under conditions of local agricultural practice. 14C-residues in the harvested seeds averaged 2.25 mg/kg; corresponding to 0.37% of the applied dose. The insecticide residue in crude oil and cake amounted to 1.6 and 1.5 mg/kg, respectively. About 75% of the 14C-activity in the crude oil could be eliminated by simulated commercial processes locally used for oil refining. The refined oil had a residue level of about 0.4 ppm, mainly in the form of pirimiphos-methyl and 2-diethylamino-4-hydroxy-6-methyl pyrimidine. Refining of soybean oil fortified with 14C-pirimiphos-methyl led also to a high loss of 14C-residues (79%). The refined oil contained a residue consisting of pirimiphos-methyl and its phenol. (author). 7 refs, 1 fig., 3 tabs

  19. AMS14C dating and stable isotope plots of Late Pleistocene ice-wedge ice

    International Nuclear Information System (INIS)

    Strategy for AMS14C dating of organic micro inclusions from syngenetic ice-wedge ice is considered. AMS14C dates are interpreted in terms of fictitious aging of ice-wedge and permafrost sediments due to high concentration of allochthonous organic material. The dating of organic material from small sample, gives the reliable 14C age. The 14C dates from syngenetic ice-wedges are compared with the dates of the host sediments surrounding syngenetic ice wedges. AMS14C dating of small samples of ice-wedge ice yields to set δ18O plots from ice-wedges to the time scale and to correlate them with ice core δ18O record

  20. Use of Natural 35S to Trace Sulphate Cycling in Small Lakes, Flattops Wilderness Area, Colorado, U.S.A

    International Nuclear Information System (INIS)

    Measurements of the cosmogenically-produced 35S, a radioisotope of sulphur (t1/2 = 87 days), are reported for the Ned Wilson Lake watershed in Colorado. The watershed contains two small lakes and a flowing spring presumed to be representative of local ground water. The watershed is located in the Flattops Wilderness Area and the waters in the system have low alkalinity, making them sensitive to increases in acid and sulphate deposition. Time series of 35S measurements were made during the summers of 1995 and 1996 (July-September) at all three sites. The system is dominated by melting snow and an initial concentration of 16-20 mBq L-1 was estimated for snow melt based on a series of snow samples collected in the Rocky Mountains. The two lakes had large initial 35S concentrations in July, indicating that a large fraction of the lake water and sulphate was introduced by meltwater from that year's snowpack. In 1995 and 1996, 35S concentrations decreased more rapidly than could be accounted for by decay, indicating that other processes were affecting 35S concentrations. The most likely explanation is that exchange with sediments or the biota was removing 35S from the lake and replacing it with older sulphate devoid of 35S. In September of 1995 and 1996, 35S concentrations increased, suggesting that atmospheric deposition is important in the sulphate flux of these lakes in late summer. Sulphur-35 concentrations in the spring water were highly variable but never higher than 3.6 mBq L-1 and averaged 2 mBq L-1. Using a simple mixing model, it was estimated that 75% of the spring water was derived from precipitation of previous years

  1. 32P-postlabelling analysis of DNA adducted with urinary mutagens from smokers of black tobacco.

    Science.gov (United States)

    Peluso, M; Castegnaro, M; Malaveille, C; Talaska, G; Vineis, P; Kadlubar, F; Bartsch, H

    1990-08-01

    In order to characterize the tobacco-derived mutagens excreted in the urine of tobacco smokers, 32P-postlabelling techniques were used to examine DNA adducts formed from these mutagens with calf thymus DNA in the presence of a metabolic activation system (rat liver S9, Aroclor 1254-induced, with or without acetyl coenzyme A). Using either nuclease P1 or butanol extraction procedures, four-six and three spots, respectively, were reproducibly found on the autoradiograms in the case of the urine extract from two smokers of black tobacco. Using the urinary extract from a non-smoker, only three faint spots were detected after nuclease P1 enrichment. DNA adducts produced in smokers' urine were then compared with those formed by four N-hydroxyarylamines, N-hydroxy-2-amino-3,8-dimethyl-3H-imidazo[4,5-f]quinoxaline, N-hydroxy-2-amino-3-methyl-imidazo[4,5-f]quinoxaline, N-hydroxy-2-naphthylamine and N-hydroxy-4-aminobiphenyl. Visual inspection revealed that none of the reference aromatic amines contributed to the adduct pattern produced by the urinary mutagen(s). However, primary aromatic amines are mainly implicated as urinary mutagens because: (i) they produce frameshift mutations in Salmonella typhimurium strains, (ii) they are easily extractable with blue cotton and (iii) their mutagenicity is abolished by a nitrite treatment procedure for deamination. PMID:2387016

  2. Improving phosphorus availability from Patos phosphate rock for Eucalyptus: a study with 32P radiotracer

    International Nuclear Information System (INIS)

    Eucalyptus plantation in Brazil is generally set on low fertility soils, therefore phosphorus (P) fertilization is mandatory and increases the cost of plantation operation. Using species that more efficiently uptake phosphorus from less soluble sources is an interesting option. However, little is known about eucalyptus regarding its ability of using less soluble forms of phosphorus. The use of P by eucalyptus (E. urophylla, E. grandis, and E. urophylla E. grandis) was studied in greenhouse using a loamy-textured, hipodystrophic Typic Haplustox from the Cerrado region, and 32P isotopic method. The P sources tested were triple superphosphate (TSP), phosphate rock (PR) and the triple superphosphate mixed with PR (TSP+PR). The effectiveness of P sources in terms of increasing dry matter yield was TSP = (TSP + PR) > PR, and the P uptake followed the order (TSP + PR) > TSP > PR for both species plus the hybrid. The increase in P uptake from PR due to TSP influence was 217.3% for E. urophylla, 235.7% for E. grandis, and 28.7% for E. urophylla E. grandis, indicating an enhancement effect of TSP on the effectiveness of PR. The hybrid E. urophylla E. grandis was the most efficient genotype on P soil use and E. grandis most exigent in P fertilizer. (author)

  3. Application a {sup 32}P bioassay for P-fertilization of citrus

    Energy Technology Data Exchange (ETDEWEB)

    Song, Sung Jun; U, Zang Kual [Jeju National University, Jeju (Korea, Republic of)

    2009-06-15

    Uptake of phosphorus (as {sup 32}P) by excised root samples from Citrus trees growing in the soil with originally less than 30 mg kg{sup -1} available P was significantly lowered after P-fertilization. This effect became more prominent in the 2nd and 3rd year of the experiment. High concentration of available P in the soil (80mg kg{sup -1}) resulted in a higher P-content in the excised roots and therefore decreased P-uptake. Application of phosphate fertilizer to such soil increased the content of available P but P concentration in Citrus leaves was not significantly changed. Branch length, fruit yield, and Brix sugar in fruit juice were also not influenced. These data show that response to P-fertilization can be tested by leaf analysis, growth or yield measurement. P-uptake of excised roots harvested from the soil with available P above 150 mg kg{sup -1} reached a level of 400 {approx} 500 pg P/mg root, which indicates that P-fertilization is unnecessary at the soil of P-content above this limit.

  4. Synoviorthesis with colloidal /sup 32/P chromic phosphate for hemophilic arthropathy: clinical follow-up

    Energy Technology Data Exchange (ETDEWEB)

    Rivard, G.E.; Girard, M.; Lamarre, C.; Jutras, M.; Danais, S.; Guay, J.P.; Belanger, R.D.

    1985-11-01

    Thirty-one synoviortheses were performed in 22 joints of 14 hemophilic patients (aged 12 to 28 years) with chronic synovitis and for whom conventional treatments were considered ineffective. Except for patients with inhibitors, conventional treatments included three to six months of adequate prophylactic therapy with the missing coagulation factors, intensive physiotherapy and, when indicated, antiinflammatory agents and orthosis. Colloidal /sup 32/P chromic phosphate was injected intraarticularly in doses of 1.0 mCi for knees and of 0.5 mCi for the other joints. Time of follow-up ranged from two to five years. Frequency and importance of bleeding decreased in all patients. Effect on range of motion was best in knees. In elbows, flexion-extension was improved in four cases, unchanged in five and decreased in one; pronation-supination was decreased in four cases. The results of 13 synoviortheses in four hemophilic patients with high titer factor VIII inhibitors were comparable to those in hemophiliacs with no inhibitors. However, in three of the four patients synoviorthesis had to be repeated after two to four years for recurrence of synovitis. Extraarticular escape of radioactivity was monitored 62 times for 17 synoviortheses in 12 patients; extraarticular counts never exceeded 4% of the intraarticular counts. Chromosome aberrations were found not to be increased after treatment in the seven patients in whom adequate analysis could be done.

  5. Disposition of {sup 14}C-{beta}-carotene following delivery with autologous triacylglyceride-rich lipoproteins

    Energy Technology Data Exchange (ETDEWEB)

    Dueker, Stephen R. [Department of Nutrition, University of California, Davis 95616 (United States) and Vitalea Science, Inc. 1233 East Beamer, Woodland, CA 95776 (United States)]. E-mail: srdueker@vitaleascience.com; Le Thuy Vuong [Vitalea Science, Inc. 1233 East Beamer, Woodland, CA 95776 (United States); Faulkner, Brian [Vitalea Science, Inc. 1233 East Beamer, Woodland, CA 95776 (United States); Buchholz, Bruce A. [Center for Accelerator Mass Spectrometry, Lawrence Livermore National Laboratory, Livermore, CA 94551 (United States); Vogel, John S. [Department of Nutrition, University of California, Davis 95616 (United States); Center for Accelerator Mass Spectrometry, Lawrence Livermore National Laboratory, Livermore, CA 94551 (United States)

    2007-06-15

    Following ingestion, a fraction of {beta}-carotene is cleaved into vitamin A in the intestine, while another is absorbed intact and distributed among tissues and organs. The extent to which this absorbed {beta}-carotene serves as a source of vitamin A is unknown in vivo. In the present study we use the attomole sensitivity of accelerator mass spectrometry (AMS) for {sup 14}C to quantify the disposition of {sup 14}C-{beta}-carotene (930 ng; 60.4 nCi of activity) after intravenous injection with an autologous triacylglyceride-rich lipoprotein fraction in a single volunteer. Total {sup 14}C was quantified in serial plasma samples and also in triglyceride-rich, and low density lipoprotein, subfractions. The appearance of {sup 14}C-retinol, the circulating form of vitamin A in plasma, was determined by chromatographic separation of plasma retinol extracts prior to AMS analysis. The data showed that {sup 14}C concentrations rapidly decayed within the triglyceride-rich lipoprotein fractions after injection, whereas low density lipoprotein {sup 14}C began a significant rise in {sup 14}C 5 h post dose. Plasma {sup 14}C-retinol also appeared at 5 h post dose and its concentrations were maintained above baseline for >88 days. Based upon comparisons of {sup 14}C-retinol concentrations following an earlier study with orally dosed {sup 14}C-{beta}-carotene, a molar vitamin A value of the absorbed {beta}-carotene of 0.19 was derived, meaning that 1 mole of absorbed {beta}-carotene provides 0.19 moles of vitamin A. This is the first study to show that infused {beta}-carotene contributes to the vitamin A economy in humans in vivo.

  6. Polar ice ablation rates measured using in situ cosmogenic 14C

    International Nuclear Information System (INIS)

    Appreciable 14C can be produced in situ in polar ice when 14C was studied in CO2 extracted from both accumulation and ablation samples. In some ablation samples 14C activities were observed to be between four and six times higher than those expected due to trapped atmospheric CO2. Here we report the detection of an unambiguous signal of in situ cosmogenic 14C in ice samples from two ablation sites in the Antarctic. The 14C is produced mainly by nuclear spallations of oxygen in ice. The observed concentration of 14C in ablation ice samples is 1-3 x 103 atom per g ice - three orders of magnitude higher than expected from the amount of trapped atmospheric CO2 in this ice. The in situ 14C has a unique signature: about 60% exists as 14CO and the remainder as 14CO2. This result is consistent with that expected from studies of artificially produced 11C in solid targets. The 14C concentration is found to decrease with depth as expected for in situ production. The calculated model ablation rates are found to be 5.8 ± 0.7 and 7.6 ± 0.8 cm yr-1 at two sites from the Allan Hills main ice field, in agreement with rates determined by the stake method. Our work indicates that the 14C age of accumulation ice based on trapped (atmospheric) CO2 would be an underestimate of the true age, if a correction is not made for in situ produced 14CO2. This can be done easily because the 14C activities of both the CO and CO2 phases, as well as the trapped CO2 concentration, can be measured. (author)

  7. Appearance of circulating and tissue /sup 14/C-lipids after oral /sup 14/C-tripalmitate administration in the late pregnant rat

    Energy Technology Data Exchange (ETDEWEB)

    Argiles, J.; Herrera, E.

    1989-02-01

    Studies were performed to determine whether and/or how dietary lipids participate in maternal hypertriglyceridemia during late gestation in the rat. After oral administration of glycerol-tri(1-14C)-palmitate, total radioactivity in plasma increased more rapidly in 20-day pregnant rats than in either 19-day pregnant rats or virgin controls. At the peak of plasma radioactivity, four hours after the tracer was administered, most of the plasma label corresponded to 14C-lipids in triglyceride-rich lipoproteins (d less than 1.006), and when expressed per micromol of triglyceride, values were higher in pregnant than in virgin rats. The difference was less after 24 hours, although at this time the level of 14C-lipids in d less than 1.006 lipoproteins was still higher in 20-day pregnant rats than in virgins. Tissue 14C-lipids, as expressed per gram of fresh weight, were similar in pregnant and virgin rats, but the values in mammary glands were much higher in the former group. Estimated recovery of administered radioactivity four hours after tracer in total white adipose tissue, mammary glands, and plasma lipids was higher in pregnant than in virgin rats. No difference was found between 20-day pregnant and virgin rats either in the label retained in the gastrointestinal tract or in that exhaled as 14C-CO2 during the first four hours following oral administration of 14C-tripalmitate. These findings plus the known maternal hyperphagia, indicate that in the rat at late pregnancy triglyceride intestinal absorption is unchanged or even enhanced and that dietary lipids actively contribute to both maternal hypertriglyceridemia and lipid uptake by the mammary gland.

  8. Effects of fertilizers, fungicides and herbicides on the fate of 14C-parathion and 14C-fonofos in soils and crops

    International Nuclear Information System (INIS)

    The fate of 14C-parathion and 14C-fonofos in soil is significantly affected by the presence of organic and inorganic fertilizers, fungicides and herbicides, possibly via the effect of soil microflora. Soil microorganisms are responsible for the oxidative as well as the reductive degradation of the insecticide. Using 14carbon, the authors studied the effects of selected fungicides (benlate, captafol and manzate) herbicides (2,4-D parathion) and fertilizers ((NH4)6SO4, KNO3, urea) on pesticides in Cromberry soils. Results of the study stress the importance of investigating the environmental fate of a particular pesticide in relation to the presence of the agricultural chemicals

  9. Determination of the hydrothermal degradation products of D-(U-14C) glucose and D-(U-14C) fructose by TLC

    International Nuclear Information System (INIS)

    Hydrothermal degradation was examined using D-(U-14C) glucose and D-(U-14C) fructose. By thin layer chromatography with methylene chloride, tetrahydrofuran (THF), acetic acid - 60:20:20 as a mobile phase; it was possible to separate and identify the carbohydrates and their reaction products, glyceraldehyde, dihydroxyacetone, methylglyoxal, glycolaldehyde, 5-hydroxymethylfurfural and furfural. Up to 99% of the initial activity was determined by scintillation counting of the TL-chromatograms. A reaction scheme for the hydrothermal degradation of glucose and fructose was obtained from these results. (author)

  10. Transformation of Lesquerella Fendleri with the New Binary Vector pGPro4-35S

    Directory of Open Access Journals (Sweden)

    Grace Q. Chen

    2011-01-01

    Full Text Available Problem statement: Crop genetic engineering requires the use of various promoters to control the expression of introduced transgenes. Some of the binary vectors currently available for promoter characterization in dicotyledonous plants have pitfalls due to their construction, such as containing a selectable marker cassette with enhancer sequences that can potentially interfere with the expression specificity of nearby promoters. Also, many binary vectors are quite large in size and contain few useful restriction sites making their in vitro manipulation technically challenging. Approach: A small (7698 bp and flexible binary vector named pGPro4 was constructed to possess unique features favorable for promoter analysis in dicot plants. A nopaline synthase (nos promoter was used to control the expression of the selectable marker of pGPro4 to prevent the problem of interference with the neighboring promoter-reporter fusion. In pGPro4, the nos promoter and hygromycin phosphotransferase II (hptII sequences are flanked by loxP sites, which allow for Cre recombinase-mediated removal when hygromycin resistance is no longer desired. pGPro4 also contains a bifunctional β-glucuronidase-enhanced Green Fluorescent Protein (gusA-eGFP reporter gene that provides visual detection of reporter gene expression using either fluorescence in live cells or histochemical detection of β-glucuronidase activity. Results and Conclusion: To demonstrate the usefulness of the pGPro4 vector, a CaMV35S promoter was fused to gusA-eGFP and the resulting plasmid, pGPro4-35S, was used to transform Lesquerella fendleri. Primary shoots were generated from explants at an expected frequency of 10-27.5%, indicating that the nos promoter drove sufficient hptII expression to generate hygromycin resistant plants. Six independent transgenic L. fendleri lines were grown to maturity and generated T1 seeds. The bifunctionality of the gusA-eGFP reporter gene was verified by detecting both green

  11. Evaluation of [methyl- 14C]4'-thio-thymidine for DNA synthesis imaging in vivo

    International Nuclear Information System (INIS)

    Objective: In order to obtain a thymidine analog that might prove simpler to use for imaging DNA synthesis and follow the same biochemistry of thymidine in vivo, we evaluated [methyl- 11C]4'-thio-thymidine ([methyl- 11C]S-dThd) by using the [14C]-labeled counterpart ([methyl- 14C]S-dThd). Methods: [methyl-14C]S-dThd was synthesized by rapid methylation of 5-trimethyl-stannyl-4' -thio-2' -deoxyuridine via a palladium mediated Stille-coupling reaction with [14C]methyl iodide. Degradation of [methyl- 14C]S-dThd when incubated in human blood was analyzed by HPLC. The in vivo potential of [methyl- 14C]S-dThd was evaluated by distribution study of EMT-6 mammary carcinoma-bearing mice. Gemcitabine, a potent inhibitor of DNA synthesis, was used to modulate cell proliferation. Tissue extraction was also performed to investigate the incorporation of [methyl-14C]S-dThd into DNA. Results: [methyl- 14C]S-dThd was obtained in 31-41% radiochemical yield (calculated from [14C]methyl iodide) at 130, 5 min reaction in N,N-dimethylforamide. After semi-preparative HPLC purification, radiochemical purity of [methyl- 14C]S-dThd was >99% and the specific activity was 2.04 GBq/mmol (according to the specific activity of [14C]methyl iodide). Incubation with human blood demonstrated rapid degradation of [2- 14C]thymidine. In contrast, [methyl- 14C]S-dThd was stable with less than 3% degradation at 60 min. In vivo distribution study showed progressive accumulation of radioactivity in proliferating tissues (spleen, thymus, duodenum and tumor). On the other hand, the washout of radioactivity by the non-proliferating tissues (lung, liver, kidney and muscle) appeared nearly exponential. The tumor uptake of [methyl- 14C]S-dThd was high (8.8%ID/g at 60 min) and selective (Tumor to blood ratio: 12.2 at 60 min). Gemicitabine pretreatment significantly reduced the tumor uptake of [methyl- 14C]S-dThd. Relative blood flow as measured by the uptake 4-[N-Methyl- 14C]iodoantipyrine was similar in the

  12. The distribution of Δ14C in Korea from 2010 to 2013

    Science.gov (United States)

    Park, J. H.; Hong, W.; Xu, X.; Park, G.; Sung, K. S.; Sung, Kilho; Lee, Jong-geol; Nakanishi, T.; Park, Hyo-Seok

    2015-10-01

    Δ14C values of leaves of a deciduous tree record to those of atmospheric CO2 within error and were used to map out Δ14C distribution in Korea. We collected ginkgo (Ginkgo biloba Linnaeus, a deciduous tree) leaf samples in mid-June to early July from 2009 to 2013 in Korea to obtain the regional distribution of Δ14C. Commonly CO2 emitted from fossil fuel consumption dilutes atmospheric 14C, while operations and accidents at nuclear power plants can increase it. The distribution maps of Δ14C from 2010 to 2013 in Korea shows that Δ14C values in the northwestern and southeastern parts of Korea are lower than those of the other parts of Korea, which is consistent with the population and industry patterns. Decrease rates of annually averaged Δ14C values in Korea over the study period are larger than those of Pt. Barrow, Alaska, USA (71.3°N, 156.5°W), so the difference between them and those of Pt. Barrow, Alaska, USA became larger annually. This may be due to the increase in fossil fuel consumption in Korea and China. The decrease rate between 2010 and 2011 was smaller than in other years. This could be the effect of the Fukushima power plant accident which occurred in March 11, 2011, but further study is needed to clarify it.

  13. A study on alfalfa-dodder relationships by 14C-sucrose incorporation in their tissues

    International Nuclear Information System (INIS)

    Plant-parasite relationships between lesser-dodder (Cuscuta epithymum) and alfalfa (Medicago sativa) are investigated. 14C-sucrose was incorporated via the cut stems of host and parasite into their tissues and the content of the free sugars, keto acids and free amino acids are determined. 14C-sucrose was introduced also in lesser-dodder previously taken from the host-plant and immersed directly into radioactive sucrose. It is shown that the parasite intensively absorbs sucrose from the host-plant tissues using it as a source of energy and as a substrat for different synthetic processes. In the case when the parasite was previously taken away from the host-plant 14C-sucrose taken up directly from the solution was used for the synthesis of various compounds (carbohydrates, amino- and keto acids). The suggestion was made that the respective enzyme systems are present in dodder tissues. The 14C-glucose and 14C-fructose content is an evidence for high invertase hydrolytic activity. The presence of 14C-keto acids shows that the 14C-sucrose incorporated in lesser-dodder tissues without the mediation of the host-plant was used as a respiratory substrate by the degradation following Krebs cycle. (author)

  14. Discussion: Reporting and calibration of post-bomb 14C data

    Energy Technology Data Exchange (ETDEWEB)

    Reimer, P J; Brown, T A; Reimer, R W

    2004-10-11

    The definitive paper by Stuiver and Polach (1977) established the conventions for reporting of {sup 14}C data for chronological and geophysical studies based on the radioactive decay of {sup 14}C in the sample since the year of sample death or formation. Several ways of reporting {sup 14}C activity levels relative to a standard were also established, but no specific instructions were given for reporting nuclear weapons testing (post-bomb) {sup 14}C levels in samples. Because the use of post-bomb {sup 14}C is becoming more prevalent in forensics, biology, and geosciences, a convention needs to be adopted. We advocate the use of fraction modern with a new symbol F{sup 14}C to prevent confusion with the previously used Fm, which may or may not have been fractionation corrected. We also discuss the calibration of post-bomb {sup 14}C samples and the available datasets and compilations, but do not give a recommendation for a particular dataset.

  15. Turnover of 14C-glucose in soils and its relationship with soil characters

    International Nuclear Information System (INIS)

    The turnover of 14C-glucose added in 13 soils was studied. The turnover rate of 14C-glucose can be divided into three phases: 0 - 3d, 3 - 28d and 28 - 294d. The range of the turnover rate and half -life of 14C-glucose were 1.3 x 10-1 - 2.5 x 10-1d-1 and 3 - 5d, 0.7x 10-2 - 1.2 x 10-2d-1 and 58 - 97d, 0.5 x 10-3 - 1.4 x 10-3d-1 and 491 - 1504d, respectively. Correlation analysis showed that from 0 to 3 days the turnover rate of 14C-glucose had significant positive correlation with soil qCO2, from 3 to 28 days, the turnover rate of 14C-glucose had no significant correlation with soil physico-chemical and biological properties. The turnover rate of 14C-glucose had significant or highly significant negative correlation with soil total organic carbon, total nitrogen, CEC and significant positive correlation with soil sand content during the period from 28 to 294 days. Turnover of 14C-glucose during the third period has close correlation with soil properties

  16. 14C-photo assimilation, IAA and GA3 contents in Maize treated with aluminum

    International Nuclear Information System (INIS)

    This study was carried out to show the effect of different concentrations of aluminum (0.0, 0.1, 1.0 and 10 m M Al) on the ''14C-photo assimilation and contents of IAA (indole acetic acid) and GA3 (gibberellic acid) in maize plants grown in nutrient solution. Results of 14C-photo assimilation showed that, the highest loss of 14C was in plants treated with 10 m M Al while the lowest loss was in plants treated with 0.1 m M Al throughout the experimental period. 14C in ethanolic extract of plants treated with 1.0 and 10 m M Al was higher than that of control (0.0 Al) while 0.1 m M Al reduced 14C in ethanol extract than the control plants. In contrast to 14C in the ethanol extract, 0.1 m M Al increased 14C-bound in tissue while 1.0 and 10 m M Al decreased it as compared with the control. Al affected both IAA and GA3 contents in the same manner where slight increases were observed due to 0.1 m M and the maximum increase was observed in plants treated with 1.0 m M Al

  17. New applications of {sup 14}C measurements at the Lund AMS Facility

    Energy Technology Data Exchange (ETDEWEB)

    Stenstroem, K.

    1995-11-01

    Some new applications of accelerator mass spectroscopy (AMS) with {sup 14}C are presented. In the first part the sample preparation used for production of elemental carbon at the Lund AMS facility is described. The second part concerns the release of {sup 14}C from nuclear power plants. In a one-year study, the total airborne discharge of {sup 14}C from two Swedish reactors was measured. In another study, the fraction of {sup 14}CO{sub 2} of the total airborne {sup 14}C release was determined. The third part of the thesis involves the use of {sup 14}C in nuclear medicine. The long-term retention of {sup 14}C-labelled triolein after a fat-malabsorption test has been investigated by means of AMS by analysis of expired CO{sub 2}. The possibilities of using ultra-low amounts of activity for fat-malabsorption tests, employing AMS technique, is demonstrated. In the last part AMS and {sup 14}C-labelled tracers are used in food chemistry studies of interactions between foods and packaging materials. 22 refs, 8 figs, 2 tabs.

  18. Fate of [14C]monolinuron in potatoes and soil under outdoor conditions

    International Nuclear Information System (INIS)

    [phenyl-14C]Monolinuron was applied (2.5 and 1.9 kg/ha) to the soil surface of an outdoor lysimeter in two successive years: then, potatoes were grown. Total recovery of 14C in soil, plants, and leached water was about 55% (of 14C applied) after the first growing period and about 43% after the second growing period. Radioactivity in soil contained 77.1% (based on total 14C recovered in soil) bound residues, 15% monolinuron, and the following conversion products: N-(4-hydroxyphenyl)-N'-methoxy-N'-methylurea, N-(4-chlorophenyl)-N'-methylurea. N-(4-chlorophenyl)methylcarbamate, N-(4-chlorophenyl)-N-methyl-methylcarbamate, and 4-chloroformanilide. The leachate contained 0.8% (based on total 14C recovered in leachate) N-(4-hydroxyphenyl)-N'-methoxy-N'-methylurea. Potato plants contained 0.106 mg/kg radioactive residues in peeled tubers after one growing period and 15.94 mg/kg in the tops; after two growing periods, peeled tubers contained 0.091 mg/kg and tops contained 18.87 mg/kg radioactive residues. These residues consisted of bound 14C (57.9% of total 14C recovered in plants), N-(4-hydroxyphenyl)-N'-methoxy-N'-methylurea, N-(4-chlorophenyl)-N'-methylurea, N-(4-chlorophenyl)methylcarbamate, N-(4-chlorophenyl)-N-methyl-methylcarbamate, and 4,4'-dichlorozobenzene

  19. Partitioning of 14C-photosynthate and biomass in relation to senescence characteristics of sorghum

    International Nuclear Information System (INIS)

    The stems remaining after harvest of sorghum (Sorghum bicolor (L.) Moench) grain are a low-cost source of biomass. Semidwarf hybrids exhibiting nonsenescent characteristics may yield more stem biomass than senescent hybrids. This study compared a nonsenescent to a senescent hybrid of semidwarf sorghum using dry wt. and partitioning of 14C-photosynthate and 14C-starch at three stages. A leaf was exposed to 14CO2 or 14C-starch was injected into the middle internode of each hybrid during grain filling and at or after (post) black layer of the grain. Although dry wt. of stem internodes were significantly greater for the nonsenescent compared to the senescent hybrid, 14C-photosynthate partitioning among parts did not differ between hybrids after chase periods of 5 or 7 d. Patterns of 14C-photosynthate partitioning indicated grain, stem internodes, and lateral branches were dominant sinks at grain filling, black layer, and post black layer, respectively. Lateral branch growth comprised all of the biomass increase from black layer to post black layer. At post black layer, 47% of assimilated 14CO2 was partitioned to lateral branches. Both 14C-photosynthate and 14C-starch were remobilized from stem internodes to lateral branches of both hybrids after black layer. Although unmeasured in previous comparisons between nonsenescent and senescent sorghum hybrids, lateral branch growth limited storage of 14C-photosynthate in stem internodes and resulted in similar patterns of 14C-photosynthate partitioning for the two hybrids after black layer in this study

  20. 32P-incorporation PCR for the detection of rearrangements at the TCR-gamma locus.

    Science.gov (United States)

    Short, M A; Evans, P A; Shiach, C R; Jack, A; Richards, S; Morgan, G J

    1996-03-01

    We have adapted and developed a PCR (polymerase chain reaction)-based technique for the T-cell receptor (TCR)-gamma chain gene, which has subsequently been used for routine diagnosis. Variable-region oligonucleotide primers were chosen from subgroups I and II, and the joining region primer was from the J2 segment. The primers were used to perform a 32P-incorporation PCR, and the products were then separated on an 8% denaturing polyacrylamide gel. In our hands, this technique is more reliable than cold methods, when separation is performed on either agarose or nondenaturing polyacrylamide. The radioactive technique was used to look at 102 T-cell proliferations, of which eight of eight T-acute lymphoblastic leukemia (ALL), 24 of 34 T-non-Hodgkin's leukemia (NHL), and 35 of 60 large granular lymphocyte (LGL) expansions were clonal. Of 122 B-cell proliferations investigated, including 72 cases of B-cell lineage ALL, 36 demonstrated a T-cell rearrangement (33 ALLs and three myelomas). Samples from nonlymphoid tumors were tested and produced a normal distribution ladder of PCR products after autoradiography, a pattern also observed with antenatal and preoperative patients. The radiolabel-incorporation method detected an abnormal pattern of a ladder with prominent dark bands in 29 of 122 B-cell and 27 of 102 T-cell cases and in 0 of 49 of the nonlymphoid and normal samples. The abnormal banding patterns obtained in a proportion of the B- and T-cell cases was not readily discernible by nondenaturing-acrylamide or agarose-separation methods.

  1. Experimental dosimetry of a {sup 32}P catheter-based endovascular brachytherapy source

    Energy Technology Data Exchange (ETDEWEB)

    Piermattei, A [Istituto di Fisica, Universita Cattolica S Cuore, Rome (Italy); Fidanzio, A [Istituto di Fisica, Universita Cattolica S Cuore, Rome (Italy); Perrone, F [Azienda Ospedaliera Pisana, UO Fisica Sanitaria, Pisa (Italy); Azario, L [Istituto di Fisica, Universita Cattolica S Cuore, Rome (Italy); Grimaldi, L [Istituto di Fisica, Universita Cattolica S Cuore, Rome (Italy); Viola, P [Istituto di Fisica, Universita Cattolica S Cuore, Rome (Italy); Capote, R [Dpto Fisiologia Medica y Biofisica, Facultad de Medicina, Universidad de Sevilla, Avda Sanchez Pizjuan 4, E41009 Sevilla (Spain)

    2003-08-07

    The experimental dosimetry in a water phantom of a {sup 32}P linear source, 20 mm in length, used for the brachytherapy of coronary vessels is reported. The source content activity, A, was determined by means of a calibrated well ion-chamber and the value was compared with the contained activity reported in the manufacturer's certification. In this field of brachytherapy dosimetry, radiochromic film supplies a high enough spatial resolution. A highly sensitive radiochromic film, that presents only one active layer, was used in this work for the source dosimetry in a water phantom. The radiochromic film was characterized by electron beams produced by a clinical linac. A Monte Carlo calculation of beta spectra in water at different distances along the source transverse bisector axis allowed to take into account the low dependence of film response from the electron beam energy. The adopted experimental set-up, with the source in its catheter positioned on the film plane inside the water phantom, supplies accurate dosimetric information. The measured dose rate to water per unit of source activity at reference distance, D-dot (r{sub 0}, {theta}{sub 0})/A, in units of cGy s{sup -1} GBq{sup -1}, was in agreement with the value reported in the manufacturer's certification within the experimental uncertainty. The radial dose function, g(r), is in good agreement with the literature data. The anisotropy function F(r, {theta}) is also reported. The analysis of the dose profile obtained at 2 mm from the source longitudinal axis shows that the uniformity is within 10% along 75% of the 20 mm treatment length. The adopted experimental set-up seems to be adequate for the quality control procedure of the dose homogeneity distribution in the water medium.

  2. Synthesis of the rice herbicide HW-52 [dichlorophenyl ring-14C(U)

    International Nuclear Information System (INIS)

    14C-labeled 2', 3'-dichloro-4-(ethoxymethoxy)benzanilide (HW-52) was synthesized in a total of 9 steps from 1,3-dinitrobenzene [14C(U)]. The key intermediate 2,3-dichloroaniline [14C(U)] was prepared from the starting material by a series of aromatic substitutions and functional group manipulations. Conversion to the final product was achieved in high yield by coupling and further functional group manipulations. The overall radiochemical yield was 1.88% and radiochemical purity of the product was greater than 98.8%. (author)

  3. 14C of grasses as an indicator of fossil fuel CO2 pollution

    OpenAIRE

    Lichtfouse, Eric; Lichtfouse, Michel; Kashgarian, Michaele; Bol, Roland

    2005-01-01

    Submitted version International audience Measuring the amount of fossil fuel carbon stored in the vegetation is now crucial to understand the mechanisms ruling climate changes. In this respect, highly polluted areas such as major towns represent "natural" laboratories because fossil fuel CO2 (14C-free) is isotopically distinct from mean atmospheric CO2 (14C-labeled). Here, a 14C study of urban grasses near a major highway in Paris, France, shows that plants store up to 13% of fossil fue...

  4. Timing is Everything:The Boon and Bane of 14C Geochronology

    Energy Technology Data Exchange (ETDEWEB)

    Guilderson, T; Guilderson, T; Reimer, P J; Brown, T

    2004-10-29

    There are underappreciated limitations of the conversion of {sup 14}C-ages to the fixed, calendrical time-scale that bear directly upon our understanding of the dynamic climate system, or the relationship between the collapse of one civilization and it's neighbor's. In this paper we present a quantitative assessment of the limits of {sup 14}C-geochronology and calibration onto the absolute calendrical time-scale over the Holocene. We take into account not only the inherent limitations of the {sup 14}C-calendar calibration curve, but also analytical uncertainties.

  5. Confirmation of eradication of Helicobacter pylori infection by 14C-urea breath test

    International Nuclear Information System (INIS)

    Helicobacter pylori (H. pylori) is a potent urease producer, a characteristic that has been exploited in the development of the 14C-urea breath test (UBT). 14C-UBT is being used as a highly reliable test for the diagnosis of H. pylori infection. There is paucity of reports on the utility of this test to confirm the H. pylori eradication after its treatment. The study was conducted to determine the utility of 14C-UBT in confirming the eradication of H. pylori

  6. 14C-triolein breath test in the diagnosis of steatorrhea

    International Nuclear Information System (INIS)

    The 14C-triolein breath test was evaluated as a screening test for steatorrhea in 66 consecutive patients. Steatorrhea was found in 20 patients. Following an oral dose of 14C-triolein, 14CO2-activity in the expiratory air was measured after zero, three, four, five and six hours. Maximum 14CO 2-expiration was calculated. The ability of the test to discriminate between patients with steatorrhea and patients without steatorrhea showed a specificity of 98%, and a sensitivity of 85%. Thus the 14C-triolein test seems to be sufficiently accurate as a screening test for steatorrhea

  7. Natural Abundance 14C Content of Dibutyl Phthalate (DBP from Three Marine Algae

    Directory of Open Access Journals (Sweden)

    Kazuyo Ukai

    2006-11-01

    Full Text Available Abstract: Analysis of the natural abundance 14C content of dibutyl phthalate (DBP from two edible brown algae, Undaria pinnatifida and Laminaria japonica, and a green alga, Ulva sp., revealed that the DBP was naturally produced. The natural abundance 14C content of di-(2-ethylhexyl phthalate (DEHP obtained from the same algae was about 50-80% of the standard sample and the 14C content of the petrochemical (industrial products of DBP and DEHP were below the detection limit.

  8. 14C measurement: effect of variations in sample preparation and storage on the counting efficiency for 14C using a carbo-sorb/permafluor E+ liquid scintillation cocktail

    International Nuclear Information System (INIS)

    The effect of variations in sample preparation and storage on the counting efficiency for 14C using a Carbo-Sorb/PermafluorE+ liquid scintillation cocktail has been studied, and optimum conditions are recommended. (author). 2 refs., 2 tabs., 4 figs

  9. Ovarian 32P uptake in the homoplastic hypophysectomized catfish, Heteropneustes fossilis as an end point for gonadotropin bioassay

    International Nuclear Information System (INIS)

    Ovarian 32P incorporation in hypophysectomized Heteropneustes fossilis in response to pituitary gland extract pooled from same species and mammalian gonadotropic preparations were studied. Maximum 32P uptake by ovary was obtained when a tracer dose of radiophosphorus was given 30 minutes after LH injection and fish were sacrificed 12 hours after the tracer shot. A log-dose response was observed between ovarian 32P uptake and gonadotropic content of pituitary extract or LH in hypophysectomized H. fossilis. This response was specific because FSH, TSH, prolactin and growth hormone injections failed to induce dose dependent and significant 32P uptake by ovary in similar assay recipients. However, FSH along with LH at higher dosage yielded an additive response. Also a parallelism of log-dose response was obtained between fish pituitary gonadotropin and ovine LH. Index of precision (Λ) was less than 0.214. Since donors and recipients were of the same species this bioassay of 12.5 hours for estimation of total gonadotropic potency seems to be rapid, reliable, sensitive and free from phylogenetic species specificity interaction between hormone and its receptor. (author)

  10. Effect of 32P-colloid interstitial irradiation on the treatment of occult lymphatic metastasis during lung cancer resection

    International Nuclear Information System (INIS)

    Objective: To study the effectiveness of interstitial irradiation by 32P-colloid on the occult metastasis during lung cancer resection. Methods: Seventy-three patients with lung cancer underwent resection of the tumor and interstitial administration of 32P-colloid. At the same period, 58 matched patients underwent surgical therapy only and served as the control group. After operation the dynamic distribution of body surface 32P-colloid activity, incidence of complications, rates of supra-clavicular lymph node (SCL) metastasis in different pathologic patterns, and survival rates at 1, 3, 5 years after treatment were studied. Results: No operative death occurred in these two groups. The incidences of lymph node metastasis and the incidences of major complications after operation were of no prominent differences between these two groups (χ2=0.012, 2.082, 0.003, P>0.05; χ2=0.021-0.144, P>0.05). The incidence of post-operative SCL metastasis in surgery plus 32P-colloid group was prominently lower than that in control group (χ2=4.507-5.348, P2=0.659, P>0.05), but the differences of the 3-, 5-year survial rates between the groups were prominent (χ2=4.207, 3.997, P32P-colloid during resection of lung cancer is a safe and effective procedure for controlling the occult lymphatic metastatic lesions and diminishing the focal relapse and distant metastasis, and it is bound to prolong the survival time of the patients. (authors)

  11. Effect of anticonvulsant drugs on (/sup 35/S)t-butylbicyclophosphorothionate binding in vitro and ex vivo

    Energy Technology Data Exchange (ETDEWEB)

    Pitkaenen, A.; Riekkinen, P.J.; Saano, V.; Tuomisto, L.

    1987-01-01

    Using several concentrations of eight anticonvulsant drugs in clinical use (carbamazepine, clonazepam, phenytoin, phenobarbital, ethosuximide, primidone, sodium valproate, and D,L-..gamma..-vinyl GABA), we studied their abilities in vitro to displace (/sup 35/S)t-butylbicyclophosphorothionate (/sup 35/S-TBPS) from its binding site in a homogenate of rat brain. Thereafter ethosuximide (150 mg/kg), phenobarbital (30 mg/kg), clonazepam (0.3 mg/kg), or phenytoin (100 mg/kg) was injected intraperitoneally into rats for 16-20 days; and the effect of drug administration on /sup 35/S-TBPS binding was studied in the cortex and hippocampus ex vivo. Phenobarbital (100 ..mu..M, P<0.001), ethosuximide (500 ..mu..M, P<0.001), and phenytoin (40 ..mu..M, P<0.001) decreased the specific /sup 35/S-TBPS binding in vitro by 10-16%. After drug administration of phenobarbital (concentration in plasma 168 ..mu..M), the number of binding sites decreased and the binding affinity (p<0.05) in the cortex increased. Other anticonvulsants did not modulate /sup 35/S-TBPS binding in vitro at the concentration analogous to therapeutic plasma levels or ex vivo at the dose used. These results suggest that the use of phenobarbital may modulate the TBPS binding site, but the role of the present findings in the anticonvulsant action of phenobarbital needs to be further studied.

  12. Synthesis of 2, 4-- dichloro phenoxy acetic acid [ Carboxy- 14 C] as herbicide

    International Nuclear Information System (INIS)

    One of the important herbicide, that can be used for the practical mechanism investigations and studies of metabolism functions of different plants is 2,4 dichlorophenoxy acetic acid compound. In this article, the production method for labeling the titled compound is explained. At the first stage of this research work, barium[14C] carbonate is converted into potassium [14C] by using potassium azid at a reasonable temperature. Then, after a few synthesis reaction, the compound 2,4 dichlorophenoxy methyl iodide is produced via 2,4 dichlorophenoxy as a starting material. At the next stage, the real material as a herbicide: 2,4 dichlorophenoxy acetic acid [carboxy- 14C] is prepared and produced, by the coupling reaction between 2,4 dichlorophenoxy methyl iodide and potassium [14C] cyanide, and then the resulting nitrile has been hydrolyzed

  13. The 14C(n,γ) cross section between 10 keV and 1 M

    CERN Document Server

    Reifarth, R; Forssén, C; Besserer, U; Couture, A; Dababneh, S; Dörr, L; Görres, J; Haight, R C; Käppeler, F; Mengoni, A; O'Brien, S; Patronis, N; Plag, R; Rundberg, R S; Wiescher, M; Wilhelmy, J B

    2008-01-01

    The neutron capture cross section of 14C is of relevance for several nucleosynthesis scenarios such as inhomogeneous Big Bang models, neutron induced CNO cycles, and neutrino driven wind models for the r process. The 14C(n,γ) reaction is also important for the validation of the Coulomb dissociation method, where the (n,γ) cross section can be indirectly obtained via the time-reversed process. So far, the example of 14C is the only case with neutrons where both, direct measurement and indirect Coulomb dissociation, have been applied. Unfortunately, the interpretation is obscured by discrepancies between several experiments and theory. Therefore, we report on new direct measurements of the 14C(n,γ) reaction with neutron energies ranging from 20 to 800 keV.

  14. Production and release of 14C from a swimming pool reactor

    International Nuclear Information System (INIS)

    The annual production rate of 14C in the Apsara swimming pool reactor works out to be about 2.94 mCi. The concentration distribution of 14C in different compartments viz. pool water, reactor hall air and ion-exchange resin ranged from 200 to 440 pCi/l, 0.09 to 0.38 pCi/l, an average concentration of 8.16 pCi/g respectively. The mean residence time of 14C in pool water is evaluated to be about 7 days taking into account various sinks. The study revealed atmospheric exchange at the air-water interface as the dominant process responsible for the loss of 14C from the pool water. (author). 7 refs., 2 figs., 4 tabs

  15. 14C-labeled lignins as substrates for the study of lignin biodegradation and transformation

    International Nuclear Information System (INIS)

    Methods, both classical and isotopic, for quantifying lignin degradation are reviewed. Preparation and chemical characterization of 14C-labeled lignins (both synthetic and plant-synthesized) are reviewed, with emphasis on the utilization of these 14C-labeled substrates in biodegradation and biotransformation experiments. The scientific literature is reviewed concerning the use of 14C-lignins to examine the following: microbial groups that are able to degrade lignins; lignin degradation in natural environments; biochemistry and microbial physiology of lignin degradation; biodegradability of industrial lignins and their by-products; and screening for industrially valuable, lignin-modifying microorganisms. Recent results obtained in our laboratory concerning lignin degradation by eubacteria are presented. Future directions for 14C-methodology are examined

  16. Systemic distribution of sup 14 C-labeled formaldehyde applied in the root canal following pulpectomy

    Energy Technology Data Exchange (ETDEWEB)

    Hata, G.I.; Nishikawa, I.; Kawazoe, S.; Toda, T.

    1989-11-01

    The systemic distribution of {sup 14}C-labeled formaldehyde which had been placed in the root canals of the canines of cats following pulpectomies was studied using liquid scintillation counting and whole-body autoradiographic technique. Radioactive {sup 14}C which had been placed in the canals was found in the plasma 30 min after the root canal procedure. The recovery of systemic {sup 14}C radioactivity increased with time. In addition, it seemed that approximately 3% of the dose placed in the teeth was excreted in the urine within 36 h. Whole-body autoradiograms indicated extensive concentration of {sup 14}C radioactivity in tissues other than those analyzed with the liquid scintillation technique.

  17. The metabolism of L-[6-14C] ascorbic acid in detached grape leaves

    International Nuclear Information System (INIS)

    Grape leaves (Vitis labrusca L.) that are removed from the position opposite the flower cluster either 28 or 14 days before anthesis cleave L-ascorbic acid (AA) at the C4-C5 bond into a C4 and, presumably, a C2 fragment. Leaves taken from this position 14 days after anthesis fail to cleave AA. The C4 fragment is utilized for L(+)-tartaric acid (TA) biosynthesis while the C2 fragment is recycled into hexose and products of the hexose metabolism. When ( 6-14C ) AA is the source of the label, the sucrose-drived glucose from labeled leaves has a distribution of 14C in the carbon skeleton as follows: C1, 35%; C2, 14%; C3, 4%; C(4 + 5), 13% and C6, 34%. The effect of inhibitors of the glycolate pathway on ( 6-14C ) AA metabolism is examined. (author)

  18. Synthesis and analysis of the opioid analgesic [[sup 14]C]-fentanyl

    Energy Technology Data Exchange (ETDEWEB)

    Bagley, J.R.; Wilhelm, J.A. (Anaquest Inc., Murray Hill, NJ (United States))

    1992-11-01

    The synthesis of [[sup 14]C]-fentanyl, the radiolabelled congener of the potent opioid analgesic chosen for utilization in drug disposition studies, is described. [[sup 14]C]-Labelling was achieved in the first of two steps, a room temperature reduction of the in situ generated Schiff base from 1-phenylethyl-4-piperidone and [UL-[sup 14]C]-aniline hydrochloride with sodium triacetoxyborohydride. A nearly instantaneous production of fentanyl was accomplished at room temperature with the addition of propionyl chloride. The overall radiochemical yield was 18%. The method described is efficiently adaptable for submicromolar scale while yielding a product of sufficient specific activity for in vivo studies. Our solvent system for thin layer chromatography was superior to the USP system reported for chromatographic analysis of fentanyl. This is the first reported preparation of [[sup 14]C]-fentanyl with the radiolabel in the aniline benzene ring. (author).

  19. Effect of HF leaching on {sup 14}C dates of pottery

    Energy Technology Data Exchange (ETDEWEB)

    Goslar, Tomasz, E-mail: goslar@radiocarbon.pl [Faculty of Physics, Adam Mickiewicz University, ul. Umultowska 85, 61-614 Poznan (Poland); Poznan Radiocarbon Laboratory, ul. Rubiez 46, 61-612 Poznan (Poland); Kozlowski, Janusz [Institute of Archaeology, Jagiellonian University, ul. Golebia 11, 30-007 Krakow (Poland); Szmyt, Marzena [Institute for Eastern Studies, Adam Mickiewicz University, ul. 28 Czerwca 1956 nr 198, 61-486 Poznan (Poland); Czernik, Justyna [Poznan Radiocarbon Laboratory, ul. Rubiez 46, 61-612 Poznan (Poland)

    2013-01-15

    This paper presents the experiments with {sup 14}C dating of two potsherds, which contained carbon dispersed rather homogeneously in their clay fabric. After AAA treatment, the potsherds still appeared to be contaminated with young carbon, presumably connected with humic acids. To make removal of humic acids more effective, we treated the sherds with HF acid of different concentration. The {sup 14}C results obtained demonstrate that HF treatment indeed helps to remove humic contaminants, but it also mobilizes carbon bound to raw clay, which may make {sup 14}C dates too old. We conclude therefore, that using a simple combination of HF and AAA treatment seems insufficient in reliable {sup 14}C dating of carbon homogeneously dispersed in the volume of potsherds.

  20. Influence of oral and esophageal commensal microflora on 14C-urea breath test

    International Nuclear Information System (INIS)

    Full text: Seventeen gastritis patients (12M: 5F; mean age: 40 y) were studied to evaluate the influence of oral and esophageal urease producing commensal microflora on the 14C-urea breath test(UBT). To determine the influence of oral bacterial on UBT, 111 kBq14C-urea in 10 ml water was given orally to 6 H.pylori negative subjects, with the instructions to expectorate the tracer after 30 sec. To evaluate the influence normal esophageal flora on UBT, the tracer was given to 11 patients (4 H.pylori-ve :7 H.pylori +ve) in the capsule and again after 6 h in water. One mmol C02 was collected before and up to 30 min. of tracer administration and 14C content measured. When given as mouth wash, 14C-urea liquid caused an immediate peak of 14C02 at 2 min (4263 ± 1024 dpm) and thereafter declined sharply reaching base line value after 10 min (208 ±62 dpm). When tracer was given in capsule, 14C02 level in H.pylori +ve patients increased significantly within 5 min and peaked at 10-15 min. (8644 ± 987 dpm at 15 min). However, when the tracer was given in liquid, 14CO2 levels were almost similar to those of 14C-urea mouth wash experiment in H.pylori -ve patients. It is therefore, concluded that normal commensal microflora present in the oropharynx and esophagus contribute significantly to 14C-UBT. For the accurate diagnosis of H.pylori infection, the tracer should therefore, be given in the capsule

  1. Seasonally Resolved Surface Water (delta)14C Variability in the Lombok Strait: A Coralline Perspective

    Energy Technology Data Exchange (ETDEWEB)

    Guilderson, T P; Fallon, S J; Moore, M D; Schrag, D P; Charles, C D

    2008-04-23

    We have explored surface water mixing in the Lombok Strait through a {approx}bimonthly resolved surface water {Delta}{sup 14}C time-series reconstructed from a coral in the Lombok Strait that spans 1937 through 1990. The prebomb surface water {Delta}{sup 14}C average is -60.5{per_thousand} and individual samples range from -72{per_thousand} to 134{per_thousand}. The annual average post-bomb maximum occurs in 1973 and is 122{per_thousand}. The timing of the post-bomb maximum is consistent with a primary subtropical source for the surface waters in the Indonesian Seas. During the post-bomb period the coral records regular seasonal cycles of 5-20{per_thousand}. Seasonal high {Delta}{sup 14}C occur during March-May (warm, low salinity), and low {Delta}{sup 14}C occur in September (cool, higher salinity). The {Delta}{sup 14}C seasonality is coherent and in phase with the seasonal {Delta}{sup 14}C cycle observed in Makassar Strait. We estimate the influence of high {Delta}{sup 14}C Makassar Strait (North Pacific) water flowing through the Lombok Strait using a two endmember mixing model and the seasonal extremes observed at the two sites. The percentage of Makassar Strait water varies between 16 and 70%, and between 1955 and 1990 it averages 40%. During La Nina events there is a higher percentage of Makassar Strait (high {Delta}{sup 14}C) water in the Lombok Strait.

  2. Application of the glycocolate 14C breath test in the stydy of rosacea

    International Nuclear Information System (INIS)

    Small bowel bacterial contamination was determined in patients affected by rosacea normal or gastric hyposecretors. The Breath Test 14C was used with glycocolate 14C Na. The study was completed by determination of gastric acidity, Key test, Schilling test and d xilosa test with positive results. Metronidazol was administered to these patients, thus normalizing the small bowel contamination and, at the same time, improving the dermatological process. (M.E.L.)

  3. [14C]urea breath test for diagnosis of Helicobacter pylori

    International Nuclear Information System (INIS)

    H. pylori is a potent urease producer, a characteristic that has been exploited in the development of the [14C]- and [13C]urea breath tests. The prevalence of H. pylori infection also is known to increase with advancing age; however, the individual patient's age has not routinely been considered when interpreting urea breath test results. The aim of this study was to validate a short, age-adjusted [14C]urea breath test for use in diagnosing H. pylori infections. Forty-one subjects (28 volunteers, 13 patients) underwent esophagogastroduodenoscopy with biopsies. Subjects were defined as being H. pylori-positive if histology or culture was positive. In addition, all subjects completed a 120-min [14C]urea breath test. A logistic regression analysis adjusting for age was used to estimate the probability of H. pylori positivity as a function of the 14C values generated. Sixteen subjects were H. pylori-positive, and 25 were H. pylori-negative. The 14C values generated between 15 and 80 min were found to be equally predictive in identifying H. pylori-positive subjects. Advancing age was associated with a higher probability of H. pylori-positivity. By taking advantage of the statistical probabilities, older patients could be accurately diagnosed with H. pylori at lower 14C values. We found that [14C]urea breath test to be both a sensitive and specific test that can be abbreviated to a 30-min examination (total test time). Moreover, our mathematical model indicates that a patient's age should be considered in order to optimize interpretation of the [14C]urea breath test, although further observations are needed to confirm this model

  4. Fate of (14)C-organic pollutant residues in composted sludge after application to soil.

    Science.gov (United States)

    Haudin, Claire-Sophie; Zhang, Yuhai; Dumény, Valérie; Lashermes, Gwenaëlle; Bergheaud, Valérie; Barriuso, Enrique; Houot, Sabine

    2013-08-01

    Organic micropollutants may be present in biosolids, leading to soil contamination when they are recycled in agriculture. A sludge spiked with (14)C-labelled glyphosate (GLY), sodium linear dodecylbenzene sulphonate (LAS), fluoranthene (FLT) or 4-n-nonylphenol (NP) was composted with green waste and the fate of the (14)C-micropollutant residues remaining after composting was assessed after the compost application to the soil. (14)C-residues were mineralised in the soil and represented after 140d 20-32% of the initial activity for LAS, 16-25% for GLY, 6-9% for FLT and 4-7% for NP. The (14)C-residues at the end of composting that could not be extracted with methanol or ammonia were minimally remobilised or even increased for FLT. After 140d, non-extractable residues represented 38-52% of all of the (14)C-residues remaining in the soil for FLT, 50-67% for GLY, 91-92% for NP and 94-97% for LAS and in most cases, less than 1% of the (14)C-residues were water soluble, suggesting a low direct availability for leaching and microbial or plant assimilation. FLT was identified as the main compound among the methanol-extractable (14)C-residues that may be potentially available. The fate of the (14)C-organic pollutant residues in composts after application to soil could be assessed through a sequential chemical extraction scheme and depended on the chemical nature of the pollutant. PMID:23545187

  5. Some chemical synthesis of 14C labelled compounds of pharmaceutical or biological interest

    International Nuclear Information System (INIS)

    The recent discovery of the tuberculostatic properties of the hydrazide of isonicotinic acid (so-called 'Isoniazide', 'Rimifon') has raised considerably its interest, as for metabolic studies which it is more interesting to have it labelled with 14C. We describe in this report the chemical synthesis of 14C carboxyl labelled isoniazide which were done in the pyridine ring to highlight his metabolic function on the Koch's bacillus. (M.B.)

  6. Some chemical synthesis of {sup 14}C labelled compounds of pharmaceutical or biological interest

    Energy Technology Data Exchange (ETDEWEB)

    Pichat, I.; Baret, C.; Audinot, M.; Herbert, M.; Lambin, J. [Commissariat a l' Energie Atomique, Lab. du Fort de Chatillon, Fontenay-aux-Roses (France). Centre d' Etudes Nucleaires

    1955-07-01

    The recent discovery of the tuberculostatic properties of the hydrazide of isonicotinic acid (so-called 'Isoniazide', 'Rimifon') has raised considerably its interest, as for metabolic studies which it is more interesting to have it labelled with {sup 14}C. We describe in this report the chemical synthesis of {sup 14}C carboxyl labelled isoniazide which were done in the pyridine ring to highlight his metabolic function on the Koch's bacillus. (M.B.)

  7. Assessing open-system behavior of 14C in terrestrial gastropod shells

    Science.gov (United States)

    Rech, J.A.; Pigati, J.S.; Lehmann, S.B.; McGimpsey, C.N.; Grimley, D.A.; Nekola, J.C.

    2011-01-01

    In order to assess open-system behavior of radiocarbon in fossil gastropod shells, we measured the 14C activity on 10 aliquots of shell material recovered from Illinoian (~190-130 ka) and pre-Illinoian (~800 ka) loess and lacustrine deposits in the Midwestern USA. Eight of the 10 aliquots yielded measurable 14C activities that ranged from 0.25 to 0.53 percent modern carbon (pMC), corresponding to apparent 14C ages between 48.2 and 42.1 ka. This small level of open-system behavior is common in many materials that are used for 14C dating (e.g. charcoal), and typically sets the upper practical limit of the technique. Two aliquots of gastropod shells from the Illinoian-aged Petersburg Silt (Petersburg Section) in central Illinois, USA, however, yielded elevated 14C activities of 1.26 and 1.71 pMC, which correspond to apparent 14C ages of 35.1 and 32.7 ka. Together, these results suggest that while many fossil gastropods shells may not suffer from major (>1%) open-system problems, this is not always the case. We then examined the mineralogy, trace element chemistry, and physical characteristics of a suite of fossil and modern gastropod shells to identify the source of contamination in the Petersburg shells and assess the effectiveness of these screening techniques at identifying samples suitable for 14C dating. Mineralogical (XRD) and trace element analyses were inconclusive, which suggests that these techniques are not suitable for assessing open-system behavior in terrestrial gastropod shells. Analysis with scanning electron microscopy (SEM), however, identified secondary mineralization (calcium carbonate) primarily within the inner whorls of the Petersburg shells. This indicates that SEM examination, or possibly standard microscope examination, of the interior of gastropod shells should be used when selecting fossil gastropod shells for 14C dating. ?? 2011 by the Arizona Board of Regents on behalf of the University of Arizona.

  8. Synthesis of steroids 14C-4: acetates of 19-nor-testosterone and testosterone

    International Nuclear Information System (INIS)

    The acetates of 19-nor-testosterone 4-14C and testosterone 4-11C have been prepared from ICH3H814C with respective yields of 32 percents and 56 percents in report of ICH3-14C. The cyclization in acid medium has given correct yields in opposition with the cyclization in alkaline medium that gives low yields for the testosterone and negative yields for the 19-nor-testosterone

  9. Distribution of [14C]-labelled aflatoxin B1 in mice

    International Nuclear Information System (INIS)

    The distribution of [14C]-labelled aflatoxin B1 has been studied in mice with the aid of whole-body autoradiography. In addition to the localisation of labelled aflatoxin B1 and/or its metabolites in the liver, bile, kidney, lung and urine an uptake of 14C in the pigment of the Harderian gland and the eye was observed. Uptake of radioactivity was also found in the eyes of the foetuses although their livers did not accumulate radioactivity. (author)

  10. 14C release from a Soviet-designed pressurized water reactor nuclear power plant.

    Science.gov (United States)

    Uchrin, G; Csaba, E; Hertelendi, E; Ormai, P; Barnabas, I

    1992-12-01

    The Paks Nuclear Power Plant in Hungary runs with four pressurized water reactors, each of 440-MWe capacity. Sampling systems have been developed and used to determine the 14C of various chemical forms (14CO2, 14CO, 14CnHm) in the airborne releases. The average normalized yearly discharge rates for the time period 1988-1991 are equal to 0.77 TBq GWe-1 y-1 for hydrocarbons and 0.05 TBq GWe-1 y-1 for CO2. The contribution of 14CO was less than 0.5% of the total emission. The 14C discharge rate is estimated to be four times higher than the corresponding mean data of Western European pressurized water reactors. The calculated effective dose equivalent to individuals living in the vicinity of the power plant, due to 14C release, was 0.64 microSv in 1991 while the effective dose equivalent due to the natural 14C level was 15 microSv y-1. The long-term global impact of the 14C release in the operational period of the plant (1982-1991) was 1,270 man-Sv. The 14C excess in the environmental air has been measured since 1989 by taking biweekly samples at a distance of 1.7 km from the nuclear power plant. The long-term average of radiocarbon excess coming from the power plant was 2 mBq m-3. The local 14C deposition was followed by tree ring analysis, too. No 14C increase higher than the uncertainty of the measurement (four per thousand = 0.17 mBq m-3) was observed.

  11. Irradiation Scheme Design of 14C Production on 49-2 Reactor

    Institute of Scientific and Technical Information of China (English)

    SUN; Zheng; LIU; Xing-min; XU; Zhi-long; ZHANG; Ya-dong

    2012-01-01

    <正>14C is a radioisotope of carbon, it is widely used in pharmacy, medical treatment, agriculture, reconnoiter and archaeology. 49-2 research reactor is a swimming pool style reactor which has operated for more than 40 years. The application of 49-2 reactor includes the radio nuclides production. Therefore, the technical scheme on 14C irradiation in 49-2 reactor should be prepared elaborately.

  12. Model simulations of the fate of 14C added to a Canadian shield lake

    International Nuclear Information System (INIS)

    Carbon-14 was added to the epilimnion of a small Canadian Shield lake to investigate primary production and carbon dynamics. The nature of the spike and subsequent monitoring allowed the investigation of both short-term and longer-term processes relevant to evaluating impacts of accidental and routine releases and of solid waste disposal. Data from this experiment were used in the BIOMOVS II program as a validation test for modelling the fate of the 14C added to the lake. Four models were used: (1) a simple probabilistic mass balance model of a lake; (2) a relatively complex deterministic model; (3) a complex deterministic model; and (4) a more complex probabilistic model. Endpoints were 14C concentrations in water, sediment and lake whitefish over a thirteen year period. Each model produced reasonable predictions when compared to the range of the observed data and when uncertainty in model predictions is taken into consideration. The simple lake model did not account for internal recycling of 14C and, in this respect, its predictions were not as realistic as those of the more complex models for concentrations in water. However, the simple model predictions for the 14C inventory remaining in lake sediment were closest to the observed values. Overall, the more complex probabilistic model was the most accurate in simulating 14C concentrations in water and in whitefish but it overestimated 14C retention in the lake sediments, as did the other complex models. Choice of parameter values for transfer rate to sediment and gaseous evasion are important in influencing model predictions. Although predicted concentrations of 14C in fish of dynamic models were more accurate than those using equilibrium bioconcentration factors typically used in assessments, large variability in observed 14C concentrations in whitefish emphasizes the need for a better understanding of the important processes that influence these contaminant concentrations. (Copyright (c) 1998 Elsevier Science B

  13. Lack of tissue renewal in human adult Achilles tendon is revealed by nuclear bomb (14)C.

    Science.gov (United States)

    Heinemeier, Katja Maria; Schjerling, Peter; Heinemeier, Jan; Magnusson, Stig Peter; Kjaer, Michael

    2013-05-01

    Tendons are often injured and heal poorly. Whether this is caused by a slow tissue turnover is unknown, since existing data provide diverging estimates of tendon protein half-life that range from 2 mo to 200 yr. With the purpose of determining life-long turnover of human tendon tissue, we used the (14)C bomb-pulse method. This method takes advantage of the dramatic increase in atmospheric levels of (14)C, produced by nuclear bomb tests in 1955-1963, which is reflected in all living organisms. Levels of (14)C were measured in 28 forensic samples of Achilles tendon core and 4 skeletal muscle samples (donor birth years 1945-1983) with accelerator mass spectrometry (AMS) and compared to known atmospheric levels to estimate tissue turnover. We found that Achilles tendon tissue retained levels of (14)C corresponding to atmospheric levels several decades before tissue sampling, demonstrating a very limited tissue turnover. The tendon concentrations of (14)C approximately reflected the atmospheric levels present during the first 17 yr of life, indicating that the tendon core is formed during height growth and is essentially not renewed thereafter. In contrast, (14)C levels in muscle indicated continuous turnover. Our observation provides a fundamental premise for understanding tendon function and pathology, and likely explains the poor regenerative capacity of tendon tissue.

  14. Translocation of 14C-labelled photosynthetic assimilates in cassava (Manihot esculenta Crantz)

    International Nuclear Information System (INIS)

    Leaves of cassava (Manihot esculenta Crantz cv. Ankra) plants were allowed to assimilate 14CO2 in photosynthesis. Following labelling with 14C at six months of age, plants were harvested after seven days and after six months, near maturity. Additional plants were labelled at eight and twelve months of age and harvested immediately, after seven days, or near maturity. 14C in individual plant parts at each harvest was determined by liquid scintillation counting. Radioactive assimilates were recovered primarily in leaves exposed to 14CO2, in stems between these labelled leaves and the tubers, and in the tubers. All plants had two stems. Very little of the 14C assimilated by leaves on one stem was translocated into the other stem. Up to 60% of assimilated 14C went to the tubers when plants were growing rapidly. 14C assimilated during the dry season was recovered mainly in above-ground parts. Two separate estimates indicated that 40% of the assimilated 14C was lost in respiration and leaf abscission during the first week after labelling. (author)

  15. Future needs and requirements for AMS {sup 14}C standards and reference materials

    Energy Technology Data Exchange (ETDEWEB)

    Scott, E. Marian E-mail: marian@stats.gla.ac.uk; Boaretto, Elisabetta; Bryant, Charlotte; Cook, Gordon T.; Gulliksen, Steinar; Harkness, Doug D.; Heinemeier, Jan; McGee, Edward; Naysmith, Philip; Possnert, Goran; Plicht, Hans van der; Strydonck, Mark van

    2004-08-01

    {sup 14}C measurement uses a number of standards and reference materials with different properties. Historically the absolute calibration of {sup 14}C measurement was tied to 1890 wood, through the 'primary' standard of NBS-OxI (produced by the National Bureau of Standards, now NIST - National Institute of Standards and technology) subsequently replaced by NBS-OxII. These are both internationally calibrated and certified materials, whose {sup 14}C activities are known absolutely. A second tier of materials, often called secondary standards or reference materials, and including internationally recognised materials such as ANU-sucrose (now also IAEA-C6), Chinese - sucrose and the IAEA C1-C6 series, augmented by additional oxalic acid samples are also used routinely. The activity of these materials has been estimated from large numbers of measurements made by many laboratories. Recently, further natural materials from the Third and Fourth International Radiocarbon Inter-comparisons (TIRI and FIRI) have been added to this list. The activities of these standards and reference materials span both the applied {sup 14}C age range and the chemical composition range of typical samples, but this is not achieved uniformly and there is a continuing need for reference materials for laboratory quality control and measurement-traceability purposes. In this paper, we review the development of {sup 14}C standards and reference materials and consider the future requirements for such materials within the {sup 14}C AMS community.

  16. Measurement of the rate of fat absorption by the 14C-triolein breath test

    International Nuclear Information System (INIS)

    To characterize the extent to which continuous measurement of the rate of 14CO2 excretion following the oral administration of 14C-labeled triolein (14C-T) would estimate the rate of absorption of triolein by the gut, ten adult male rats were fed 0.5 ml of 14C-T and the rate of production of expired labeled CO2 was measured continuously. Pairs of animals were sacrificed at 30 min intervals between 90 and 210 min and absorption rates were calculated by quantitating substrate remaining in the gut. Comparison of these rates with the cumulative excretion rates of labeled CO2 revealed a linear relationship with a correlation coefficient of 0.91. In a second experiment, adult rats received an intravenous injection of Triton WR-1339, a potent inhibitor of lipoprotein lipase, prior to receiving 14C-T. The rate of intestinal 14C-triglyceride output was determined from the increase in 14C in the blood over a 6 hr period. Comparison of the rates of intestinal secretion using Triton WR-1339 with that determined from the cumulative rates of excretion of 14CO2 revealed a correlation coefficient of 0.98. The authors conclude that rates of triglyceride absorption can be estimated in vivo by the continuous measurement of labeled CO2 excreted in breath

  17. The serum 14C-triolein/3H-oleic acid assimilation test for differential diagnosis of maldigestion and malabsorption

    International Nuclear Information System (INIS)

    In 125 consecutive patients the measurement of serum radioactivities after simultaneous ingestion of 14C-triolein and 3H-oleic acid was investigated as a test of lipid assimilation. The sum of the 2-h and 4-h concentrations of 14C in serum (se(2+4)14C) was most useful as an index of lipid assimilation, and the 2-h serum 3H/14C ratio (se-3H/14C) reflected lipid digestion. Normal values were se(2+4)14C >= 1.0% of the dose ingested per litre serum and se-3H/14C14C correlated significantly with faecal fat (r = -0.56, P 7 g/day. False-negative values appeared mainly in the patients with moderate steatorrhoea and gastrointestinal anastomoses. Only one false-positive se(2+4)14C value was found. Se-3H/14C was abnormal in 24 of the 34 patients with maldigestion with two false-positive results. When the results of se(2+4)14C and se-3H/14C were combined, the predictive value of the test result '' normal lipid assimilation'' was 0.75, that of the test result ''maldigestion'' was 0.93 and that of ''malabsorption'' 0.71. It is concluded that the serum 14C-triolein/3H-oleic acid assimilation test is convenient and inexpensive and may be useful when quantitative faecal collections are not available

  18. Fate of organochlorine 14C-dicofol in a lab-scale wastewater treatment Destino do organoclorado 14C-dicofol no tratamento de efluentes

    Directory of Open Access Journals (Sweden)

    Jaime L. M. Oliveira

    2008-06-01

    Full Text Available The fate of organochlorine 14C-dicofol in activated sludge process was investigated. Results showed that the major part of radioactivity remained adsorbed on biological sludge. Consequently, its final disposal deserves special attention. The small amounts of dicofol, biotransformed or not, which remained in the treated effluent could contaminate receiving bodies.A dinâmica do organoclorado 14C-dicofol no processo de lodos ativados foi investigada. Os resultados mostraram que a maior parte da radioatividade ficou adsorvida no lodo biológico. Consequentemente, o seu descarte final merece atenção especial. Pequenas quantidades de dicofol, biotransformadas ou não, permanecem no efluente tratado podendo contaminar os corpos receptores.

  19. Release of 14C from the gap and grain-boundary regions of used CANDU fuels to aqueous solutions

    International Nuclear Information System (INIS)

    This study was undertaken as part of the Canadian Nuclear Fuel Waste Management Program (CNFWMP), to measure 14C inventories of used CANDU fuel. Other objectives were to measure the fraction of the total 14C inventory that would be instantly released to solution from used CANDU fuels upon sheath failure and to determine if the assumptions made in safety assessment calculations of used fuel waste disposal regarding instant release of 14C were correct. Results showed that the measured 14C inventories were a factor of 11.5 ± 3.9 lower than the estimated 14C inventory values used in safety assessment calculations. Measured instant release values for 14C ranged from 0.06 to 5.04% (of total 14C inventories) with an average of 2.7 ± 1.6%, indicating that instant release fractions for 14C used in safety assessment calculations (1.2--25%) were overestimated

  20. /sup 14/C isotope effects in /sup 1/H and /sup 13/C N. M. R. spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Funke, C.W.; Kaspersen, F.M.; Sperling, E.M.G.; Wagenaars, G.N.

    1986-03-15

    Replacement of /sup 12/C by /sup 14/C induces small upfield shifts of the directly bonded /sup 1/H and /sup 13/C nuclei; these shift differences can be used to measure the extent of /sup 14/C labelling.

  1. Biodegradation of {sup 14} C-atrazine under outdoor conditions; Biodegradacao de {sup 14} C-atrazina em condicoes semi controladas

    Energy Technology Data Exchange (ETDEWEB)

    Queiroz, Brigida Pimentel Villar de

    1997-10-01

    Uniformly {sup 14} C-ring labeled atrazine (5 L/ha) was applied to a Typical Hapludox Brazilian Soil sample which was incubated under outdoor conditions. Sample of 200 g (dry weight base) of fresh soil were distributed in Erlenmeyer flasks and the moisture was adjusted for 2/3 rds of the soil field capacity. The flasks were then buried in the Lysimeter Station when they were incubated. The experiment started jointly with a corn planting. The {sup 14} C O{sub 2} was analyzed every 15 day, during a period of 150 days. The desorbed, extracted and bound residues were analyzed. The extracted soil was fractionated and the residues in the humin, fulvic and humic acids were determined. At the end of the incubation period (150 days), the {sup 14} CO{sub 2} evolved reached up to 36% of the total applied activity, the bound residues were detected in about the same (34%) during the inoculation period, and were distributed in the fractions of fulvic acids (29,91%), humic acids (6,83%) and humin (63,26%). The metabolites formed in the desorbed residues and in the extracted residues were determined using thin layer chromatography with {sup 14} C-detector. After 150 days incubation, desorbed soil residues were identified as atrazine (52,72%), hydroxiatrazine (44%) and desisopropilatrazine (3,28%). The extractable residues contained atrazine (79,29%), hydroxiatrazine (16,22%), desisopropilatrazine (2,25%) and desetylatrazine (2,24%). (author)

  2. Effect of cytochalasin B on 3-O-[(14)C]-methyl-D-glucose or D-[U-(14)C]glucose handling by BRIN-BD11 cells.

    Science.gov (United States)

    Cetik, Sibel; Rzajeva, Aigun; Malaisse, Willy J; Sener, Abdullah

    2014-07-01

    The present study aimed to investigate the effects of cytochalasin B (20 μM) on the uptake of 3-O-[(14)C]-methyl-D-glucose or D-[U-(14)C]glucose (8.3 mM each) by BRIN-BD11 cells. Taking into account the distribution space of tritiated water ((3)HOH), which was unexpectedly increased shortly after exposure of the cells to cytochalasin B and then progressively returned to its control values, and that of L-[1-(14)C]glucose, used as an extracellular marker, it was demonstrated that cytochalasin B caused a modest, but significant inhibition of the uptake of D-glucose and its non-metabolized analog by the BRIN-BD11 cells. These findings resemble those observed in acinar or ductal cells of the rat submaxillary gland and displayed a relative magnitude comparable to that found for the inhibition of D-glucose metabolism by cytochalasin B in purified pancreatic islet B cells. These findings reinforce the view that the primary site of action of cytochalasin B is located at the level of the plasma membrane.

  3. Stability of 125I and 14C labelled boom clay organic matter

    International Nuclear Information System (INIS)

    The candidate host formation for the disposal of radioactive waste in Belgium is boom clay which may contain up to 4% organic matter (OM). A limited fraction (less than 0.05%) of this OM is mobile. OM can complex radionuclides and so influence their migration. The migration behaviour of the OM itself has been extensively studied but to date such studies have used absorbancy measurements to quantify the OM. Unfortunately various problems accompany the use of absorbancy measurements. The particular problems may be overcome by using radiolabelled OM. Accordingly as a precursor to planned in situ migration experiments in boom clay (BC) using radiolabelled OM, stability studies on 125I and 14C labelled materials have been conducted. The 125I containing solutions were analysed using gel permeation chromatography (GPC) and the 14C solutions using high performance size exclusion chromatography (HPSEC). Dissappointingly at the relevant pH of 8.5, even in the absence of the clay, the 125I label was found to be unstable. However the 14C labelled OM (14C-BC-OM) was stable under the mild conditions employed in the test, so its stability was investigated in the presence of boom clay. The results were compared with that of 14C labelled humic acids (14C-HA), treated similarly. Unexpectedly the 14C labelled material was found to be partially unstable in the presence of boom clay. However the instability has not hampered the laboratory column experiments and should not hamper the proposed in situ experiments with this material. (orig.)

  4. Detection of human cytomegalovirus by slot-blot hybridization assay employing oligo-primed 32P-labelled probe

    International Nuclear Information System (INIS)

    A 32P-labelled Hind III-0 DNA fragment (nine Kilobases; Kb) from human cytomegalovirus AD-169 (HCMV) was used in slot-blot hybridization assay for the detection of HCMV in clinical samples. The results obtained with DNA hybridization assay (DNA HA) were compared with virus isolation using conventional tube cell culture (CTC) and centrifugation vial culture (CVC), immunofluorescence (IF), and complement fixation test (CFT). Of 15 CTC-positive samples, 13 were positive with DNA HA (sensitivity 86.7%). Also, 14 additional samples were DNA HA-positive but CTC-negative. CVC and/or IF confirmed the diagnosis in nine of 14; the remaining five samples were from three patients who showed fourfold rising antibody titre by CFT. Although DNA HA using 32P-labelled probes is relatively cumbersome and expensive, it is a valuable test for quantitation of viral shedding in patients with HCMV infections who may benefit from antiviral therapy

  5. Preparation of biologically active 32P-labeled human relaxin. Displaceable binding to rat uterus, cervix, and brain

    International Nuclear Information System (INIS)

    Relaxin is a member of the insulin family of polypeptide hormones and is known to exert its biological effects on various parts of the mammalian reproductive system. Biologically active human relaxin has been chemically synthesized based on the nucleotide sequence obtained from an ovarian cDNA clone. In the present study synthetic human relaxin was radiolabled by phosphorylation with cAMP-dependent protein kinase and [gamma-32P]ATP to a specific activity of 5000 Ci/mmol. The phosphorylated relaxin was purified on cation exchange high performance liquid chromatography and was shown to co-migrate with relaxin on sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Mass spectrometry revealed a single phosphorylated site on the B chain of relaxin. The 32P-relaxin was able to bind to a goat anti-relaxin antibody, and this binding could be displaced by unlabeled relaxin in a concentration-dependent manner. A comparison of the concentration responses of cellular cAMP production stimulated by relaxin and phosphorylated relaxin in a primary human uterine cell line showed that phosphorylation did not affect the in vitro biological efficacy of relaxin. This made it suitable for in situ autoradiographic localization of relaxin binding sites in rat uterine, cervical, and brain tissue sections. Displacement of the binding of 100 pM 32P-relaxin by 100, 10, and 3 nM unlabeled relaxin, but not by 100 nM insulin, insulin-like growth factor-I, and an insulin-like growth factor-I analog, demonstrated the high affinity and specificity of such binding. We conclude that 32P-labeled human relaxin is biologically and immunologically active and that this novel probe binds reversibly and with high affinity to classical (e.g. uterus) and unpredicted (e.g. brain) tissues

  6. Injection of sup 32 P colloid into squamous cell carcinoma of the esophagus for local disease control

    Energy Technology Data Exchange (ETDEWEB)

    Perakos, P.G.; Scheer, T.F. (Memorial Hospital of Laramie County and Wyoming College of Human Medicine, Wyoming (USA))

    1989-10-01

    Local treatment of squamous cell carcinoma of the esophagus is only modestly successful. To increase local control, we have developed a procedure to inject a boost dose of radiation into the tumor bed after completion of external beam radiotherapy. The boost dose is given with {sup 32}P, a readily available radiocolloid. {sup 32}P is a pure emitter and poses no significant radiation hazards. It can penetrate 10approx15 mm into the tumor mass and has a half-life of 14.3 days. After determination of the volume to be treated, the colloid is injected with endoscopic guidance using the same technique as used in injection scierotherapy of esophageal varices. We use the Pentax FG 34 JA operating gastroscope and a Bard disposable 0.5 cm 25 Ga retractable injection sclerotherapy needle. We deliver 150approx200 microCurie of {sup 32}P colloid diluted to 20 ml with normal saline at 10 to 20 injection sites. This boosts the radiotherapy dose of 5,500approx6,000 cGy to the range of 7,500approx8,000 cGy. We have treated five patients so far, with length of follow-up ranging from 8approx28 months. Local control and survival results have been excellent and no complications have been associated with the procedure. A combination of external beam radiotherapy and interstitial boost treatment with colloidal {sup 32}P appears to be a safe and effective method of managing squamous cell carcinoma of the esophagus. (author).

  7. Determination of lactic acid bacteria viability in the small intestine of catfish (Pangasius Djambal) by using the 32P radioisotope

    International Nuclear Information System (INIS)

    The viability of probiotics is important to be determined, as is its probiotics potency in the small intestine of fish. The result can be used as a basis to determine the feeding frequency of the probiotics to the fish. The aim of this study is to gain information about the viability of lactic acid bacteria (LAB) in the small intestine of fish by using the 32P isotope technique. Catfish (Pangasius djambal) was used as a test fish, and the LAB with the code of P2.1 PTB was the subject of the experiment. Before its viability was tested, the LAB had been labelled with radioisotope 32P, then mixed into catfish feed. Its viability could be determined by counting the activity of 32P. The results showed that the percentage of LAB viability in the small intestine of catfish declined until day 7. The percentage of LAB viability was decreased at an amount of 30% at day 3. Based on this result, the feeding frequency of LAB P2.1 PTB is every 3 days. (author)

  8. Determination of Lactic Acid Bacteria Viability in the Small Intestine of Catfish (Pangasius djambal by Using the 32P Radioisotope

    Directory of Open Access Journals (Sweden)

    I. Sugoro

    2015-10-01

    Full Text Available The viability of probiotics is important to be determined, as is its probiotic potency in the small instestine of fish. The result can be used as a basis to determine the feeding frequency of the probiotics to the fish.The aim of this study is to gain information about the viability of lactic acid bacteria (LAB in the small intestine of fish by using the 32P isotope technique. Catfish (Pangasius djambal was used as a test fish, and the LAB with the code of P2.1 PTB was the subject of the experiment. Before its viability was tested, the LAB had been labelled with radioisotope 32P, then mixed into catfish feed. Its viability could be determined by counting the activity of 32P. The results showed that the percentage of LAB viability in the small intestine of catfish declined until day 7. The percentage of LAB viability was decreased at an amount of 30% at day 3. Based on this result, the feeding frequency of LAB P2.1 PTB is every 3 days. Received: 04 October 2014 Revised: 26 March 2015; Accepted: 05 April 2015

  9. Low-level 14C methane oxidation rate measurements modified for remote field settings

    Science.gov (United States)

    Pack, M. A.; Pohlman, J.; Ruppel, C. D.; Xu, X.

    2012-12-01

    Aerobic methane oxidation limits atmospheric methane emissions from degraded subsea permafrost and dissociated methane hydrates in high latitude oceans. Methane oxidation rate measurements are a crucial tool for investigating the efficacy of this process, but are logistically challenging when working on small research vessels in remote settings. We modified a low-level 14C-CH4 oxidation rate measurement for use in the Beaufort Sea above hydrate bearing sediments during August 2012. Application of the more common 3H-CH4 rate measurement that uses 106 times more radioactivity was not practical because the R/V Ukpik cannot accommodate a radiation van. The low-level 14C measurement does not require a radiation van, but careful isolation of the 14C-label is essential to avoid contaminating natural abundance 14C measurements. We used 14C-CH4 with a total activity of 1.1 μCi, which is far below the 100 μCi permitting level. In addition, we modified field procedures to simplify and shorten sample processing. The original low-level 14C-CH4 method requires 6 steps in the field: (1) collect water samples in glass serum bottles, (2) inject 14C-CH4 into bottles, (3) incubate for 24 hours, (4) filter to separate the methanotrophic bacterial cells from the aqueous sample, (5) kill the filtrate with sodium hydroxide (NaOH), and (6) purge with nitrogen to remove unused 14C-CH4. Onshore, the 14C-CH4 respired to carbon dioxide or incorporated into cell material by methanotrophic bacteria during incubation is quantified by accelerator mass spectrometry (AMS). We conducted an experiment to test the possibility of storing samples for purging and filtering back onshore (steps 4 and 6). We subjected a series of water samples to steps 1-3 & 5, and preserved with mercuric chloride (HgCl2) instead of NaOH because HgCl2 is less likely to break down cell material during storage. The 14C-content of the carbon dioxide in samples preserved with HgCl2 and stored for up to 2 weeks was stable

  10. Betaine accumulation and (/sup 14/C)formate metabolism in water-stressed barley leaves

    Energy Technology Data Exchange (ETDEWEB)

    Hanson, A.D.; Nelsen, C.E.

    1978-01-01

    Barley (Hordeum vulgare L.) plants at the three-leaf stage were water-stressed by flooding the rooting medium with polyethylene glycol 6000 with an osmotic potential of -19 bars, or by withholding water. While leaf water potential fell and leaf kill progressed, the betaine (trimethylglycine) content of the second leaf blade rose from about 0.4 micromole to about 1.5 micromoles in 4 days. The time course of betaine accumulation resembled that of proline. Choline levels in unstressed second leaf blades were low (<0.1 micromole per blade) and remained low during water stress. Upon relief of stress, betaine-like proline-remained at a high concentration in drought-killed leaf zones, but betaine did not disappear as rapidly as proline during recovery. When (methyl-/sup 14/C)choline was applied to second leaf blades of intact plants in the growth chamber, water-stressed plants metabolized 5 to 10 times more /sup 14/C label to betaine than control plants during 22 hours. When infiltrated with tracer quantities of (/sup 14/C)formate and incubated for various times in darkness or light, segments cut from water-stressed leaf blades incorporated about 2- to 10-fold more /sup 14/C into betaine than did segments from unstressed leaves. In segments from stressed leaves incubated with (/sup 14/C)formate for about 18 hours in darkness, betaine was always the principal /sup 14/C-labeled soluble metabolite. This /sup 14/C label was located exclusively in the N-methyl groups of betaine; thus, reducing equivalents were available in stressed leaves for the reductive steps of methyl group biosynthesis from formate. Incorporation of /sup 14/C from formate into choline was also increased in stressed leaf tissue, but choline was not a major product formed from (/sup 14/C)formate. These results are consistent with a net de novo synthesis of betaine from 1- and 2-carbon precursors during water stress and indicate that the betaine so accumulated may be a metabolically inert end product.

  11. Origin and extent of atmospheric 14C variations during the past 10,000 years

    International Nuclear Information System (INIS)

    Lake sedimentation rates are, in general, variable, and changes in rate are normally local and not correlative timewise over large areas, especially as between different lakes. A possible exception is a synchronous change in sedimentation rate due to a world-wide climatic change. In addition, changes in the 14C time scale due to long-term variations in atmospheric 14C content may add 'fictitious' changes in sedimentation rate calculated from 14C dates. All sedimentary processes in suitable basins should register synchronously these fictitious changes (signal) but should not record synchronously other rate changes of local nature (noise). It is therefore possible, in principle, to separate changes due to variations in 14C time scale or a world-wide climatic change from changes due to other variations by analysing a sufficiently large number of sedimentary events and removing the synchronous variations in sedimentation rate. This study reports the detailed 14C analysis of sediments flooring three lakes: Rogers Lake, Conn., in the United States of America, Lake Victoria in Africa, and Lake Yueh Tan in Formosa. The lakes were chosen from widely different latitudes to avoid synchronous variations induced by local climatic changes. Two of the lakes, Rogers Lake and Lake Victoria, show a surprisingly steady sedimentation rate. When corrected for changes in time scale, known from tree-ring studies, the absolute sedimentation rates for both lakes appears to have been constant for the past 6000 calendar years. The sedimentation rate study affirms the change in time scale observed in 14C ages of tree rings and Egyptian samples of known ages around 2500 B. P. In addition, important synchronous changes are lacking in the sedimentation rates of all three lakes between 2500 and 10,000 years B. P. This implies that there have been neither important variations in sedimentation rates due to world-wide climatic changes nor drastic changes in the 14C time scale during this time span

  12. Tracing terrestrial carbon: a novel application of ∆14C in a humic lake

    Science.gov (United States)

    Keaveney, Evelyn; Reimer, Paula J.; Foy, Robert H.

    2016-04-01

    Lakes play an important yet underrated role in global carbon cycles. Terrestrial carbon (C) is buried and/or remineralised in significant quantities, and lake function may also be affected by catchment inputs with potential feedbacks for regional and global C cycling. Changing deposition chemistry, land use and climate induced impacts on hydrology will affect soil biogeochemistry, terrestrial C export, and hence lake ecology. Autochthonous production in lakes is based on dissolved inorganic C (DIC). DIC in alkaline lakes is partially derived from weathering of carbonaceous bedrock, a proportion of which is 14C-free. The low 14C activity yields an artificial age offset leading samples to appear hundreds to thousands of years older than their actual age. Dissolved organic carbon (DOC) and particulate organic carbon (POC) can contain terrestrial inputs. The terrestrial inputs can be labile or detrital and their age depends to a first order on their depth in catchment soil/peat stocks. We present a pilot study that uses the radiocarbon (∆14C) method to determine the source of carbon buried in the surface sediment of Lower Lough Erne, a humic, alkaline lake in northwest Ireland. ∆14C, δ13C and δ15N values were measured from phytoplankton and other biota, dissolved inorganic, dissolved organic and particulate organic carbon. A novel radiocarbon method, Stepped Combustion1 was used to estimate the degree of the burial of terrestrial carbon in surface sediment, collected in 2011. The ∆14C values of the low temperature fractions were comparable to algal ∆14C, while the high temperature fractions were 14C-depleted (older than bulk sediment). The ∆14C end-member model indicated that ~64% of carbon in surface sediment was derived from detrital terrestrial carbon. The same proportion of detrital/labile carbon was found in surface sediment of Upper Lough Erne in 2014, despite the differences in lake type and collection date. The use of ∆14C in conjunction with

  13. A method for the production of an intense negative 14C beam

    International Nuclear Information System (INIS)

    For the purpose of studying low cross section nuclear reactions the method for the production of negative ion 14C beams with a current of some μA order by means of a cylindrical source with Fe3, 14C target sputtering is developed. The source target is fabricated in the following way: 100 mg of 14C black is mixed with a binder diluted by alcohol and acetone. The mixing is continued until the solvents do not evaporate and the mixture does not take the appearance of a slightly moistsand, small portions of the mixture are pressed in a substrate deepening the target is warmed up in the air during 1h at the temperature of 200 deg C, after cooling the target is thoroughly cleaned up by alcohol from surface impurities. The source configuration admits the passage of a part of cesium beam produced at the Van-de-Graaff accelerator near the target which later is reflected back and focused on the graphite surface. At 0.5 mA cesium current the 14C negative ions beam approximately 2 μA is produced. After 500 hrs of operation the source of surface contamination behined the target by 14C particles has not been found

  14. Modulation of (14) C-labeled glucose metabolism by zinc during aluminium induced neurodegeneration.

    Science.gov (United States)

    Singla, Neha; Dhawan, D K

    2015-09-01

    Aluminium (Al) is one of the most prominent metals in the environment and is responsible for causing several neurological disorders, including Alzheimer's disease. On the other hand, zinc (Zn) is an essential micronutrient that is involved in regulating brain development and function. The present study investigates the protective potential of Zn in the uptake of (14) C-labeled amino acids and glucose and their turnover in rat brain slices during Al intoxication. Male Sprague Dawley rats (140-160 g) were divided into four different groups: normal control, Al treated (100 mg/kg body weight/day via oral gavage), Zn treated (227 mg/liter in drinking water), and Al + Zn treated. Radiorespirometric assay revealed an increase in glucose turnover after Al exposure that was attenuated after Zn treatment. Furthermore, the uptake of (14) C-labeled glucose was increased after Al treatment but was appreciably decreased upon Zn supplementation. In addition, the uptakes of (14) C-lysine, (14) C-leucine, and (14) C-aspartic acid were also found to be elevated following Al exposure but were decreased after Zn treatment. Al treatment also caused alterations in the neurohistoarchitecture of the brain, which were improved after Zn coadministration. Therefore, the present study suggests that Zn provides protection against Al-induced neurotoxicity by regulating glucose and amino acid uptake in rats, indicating that Zn could be a potential candidate for the treatment of various neurodegenerative disorders.

  15. Mineralization and Transfer Processes of 14C-labeled Pesticides in Outdoor Lysimeters

    International Nuclear Information System (INIS)

    A recently designed two-chamber-lysimeter-test-system allows the detailed investigation of degradation, transport and transfer processes of 14C-labeled substances in soil-plant-atmosphere-systems under outdoor conditions. With this test system it is feasible to distinguish between 14C-emissions from soil surfaces and 14C-emissions from plant surfaces in soil monoliths under real environmental conditions. Special soil humidity sensors allow the measurement of soil water content near to the soil surface, in 1 and 5 cm depth. The behavior of organic chemicals can be followed for a whole vegetation period and a mass balance for the applied chemical can be established. Some selected results of the herbicides isoproturon and glyphosate - using the two-chamber-lysimeter-test-system - are presented to demonstrate its applicability for the identification and quantification of the processes that govern pesticide behavior in soil-plant-systems. Mineralization of 14C-isoproturon was very different in four different soils; the mineralization capacity of the soils ranged from 2 to 60%. Leaching of isoproturon in general was very low, but depending on the soil type and environmental conditions isoproturon and its metabolites could be leached via preferential flow, especially shortly after application. For the herbicide 14C-glyphosate no accumulation of residues in the soil and no leaching of the residues to deeper soil layers could be observed after three applications. Glyphosate was rapidly degraded to AMPA in the soil. Glyphosate and AMPA were accumulated in soy bean nodules

  16. Release of aged 14C-atrazine residues from soil facilitated by dry-wet cycles

    Science.gov (United States)

    Jablonowski, N. D.; Yu, K.; Koeppchen, S.; Burauel, P.

    2012-04-01

    Intermittent dry-wet cycles may have an important effect on soil structure and aged pesticide residues release (1). A laboratory study was conducted to assess the maximum potential of water extractable aged atrazine residues influenced by soil drying and wetting. The used soil was obtained from an outdoor lysimeter (gleyic cambisol; Corg: 1.45%), containing environmentally aged (22 years) 14C-atrazine residues. For the experiment, soil from 0-10 cm depth was used since most residual 14C activity was previously found in this layer (2,3). Triplicate soil samples with a residual water content of approx. 8% were either dried (45° C) prior water addition or directly mixed with distilled water (soil+water: 1+2, w:w). The samples were shaken (150 rmp, 60 min, at 21° C), centrifuged (approx. 2000 g), and the supernatants were filtered. Water-extracted residual 14C activity was detected via liquid scintillation counter. The total water-extracted 14C activity (the amount of residual 14C activity in a sample equals 100%) was significantly higher (p

  17. An Inverse Method to Infer the Global Ocean Paleoventilation from the Atmospheric 14C Record

    Science.gov (United States)

    Marchal, O.; Hughen, K. A.; Muscheler, R.

    2001-12-01

    We present an inverse method to infer a record of global ocean ventilation (GOV) from records of atmospheric 14C activity (Δ 14C) and production. The method is based on the assimilation of activity and production data in a box model of the 14C cycle in the ocean-atmosphere-land biosphere system using the variational (adjoint) technique. It includes three components: (1) the model code that yields the value of the cost function (a measure of the misfit between observed and modelled Δ 14C); (2) the adjoint code that yields the partial derivatives of the cost function with respect to the parameters describing the temporal evolution of the GOV; and (3) an optimization procedure that yields the parameter values minimizing the cost function. Lagrange multipliers are introduced to simplify the calculation of the partial derivatives of the cost function and to construct the adjoint code directly from the model code. First we describe the method, outlining the formal similarities with the calculus of variation in analytical mechanics. Second we verify the method through the capability to recover a variety of GOV evolutions from the assimilation of artificial data ("twin experiments"). Third we apply the method to the Younger Dryas, using recent high-resolution records of Δ 14C from the Cariaco basin and of 10Be flux from Greenland ice cores. Our results give new insight into the role of the deep ocean circulation during this dramatic and rapid climate change in the circum North Atlantic area.

  18. Bioavailability of the Nano-Unit 14C-Agrochemicals Under Various Water Potential.

    Science.gov (United States)

    Jung, S C; Kim, H G; Kuk, Y I; Ahn, H G; Senseman, S A; Lee, D J

    2015-08-01

    The study was conducted to investigate the effects of water potential on bioavailability of the nano-unit 14C-cafenstrole, 14C-pretilachlor, 14C-benfuresate, 14C-simetryn and 14C-oxyfluorfen applied with or without dimepiperate or daimuron under various water potential conditions. The highest bioavailable concentration in soil solution (BCSS) was found at 60% soil moisture, while the lowest occurred at 50% soil moisture for soil-applied alone or in combination. All water potential conditions differed significantly from each other with variations in total bioavailable amount in soil solution (TBSS) when either dimepiperate or daimuron were added to the soil, and changes were directly proportional to variations in water potential. Across all treatments, TBSS at 80% soil moisture was three to four times greater than that at 50% soil moisture when applied alone or in combination with dimepiperate or daimuron. Cafenstrole and simetryn had distribution coefficient (Kd) values <64 ml g-1 and a TBSS ranging from 10 to 44 ng g-1 soil, regardless of water potential conditions applied alone or in combination. Pretilachlor and benfuresate had Kd values <15 ml g-1 and a TBSS range of 38 to 255 ng g-1 soil when applied with or without dimepiperate or daimuron. PMID:26369226

  19. Fine structure in 14C emission from 223Ra and 224Ra

    International Nuclear Information System (INIS)

    The measurement of the energy spectrum of 14C nuclei emitted in the spontaneous radioactivity of 223Ra and 224Ra has been carried out, using thin and intense sources (480 MBq for 223Ra and 3550 MBq for 224Ra). The sources were obtained by implanting mass-separated beams into Al and vitreous C catchers. The measurement was performed with a superconducting solenoidal spectrometer. Our discovery, previously reported, of fine structure in the energy spectrum of 14C emission from 223Ra, which is analogous to the one known for α emission, is confirmed. Only 13% of the branching ratio in 14C decay leads to the ground state of the residual nucleus, while 81% to the first excited state. For 14C emission from 224Ra, a lower limit of 2 for the hindrance factor has been measured for the transition to the first excited state in the residual nucleus. Also, a precise identification in Z with an ExΔE telescope has been performed for the radiation from the 223Ra source. Our measurements of fine structure in 14C emissions open this field to nuclear structure studies

  20. 14C-glucose binding assay of the glucose transporter binding sites in muscular cell membrane

    International Nuclear Information System (INIS)

    A method of determining the binding sites of glucose transporter in rat muscular cell membrane was introduced. The crude products of cell membrane form the skeletal muscle of control and insulin treated rats were prepared, and then fractionated in sucrose gradient. Both plasma membrane and microsome membrane were incubated with D-[U-14C] glucose respectively for the measurement of radioactivity and Scatchard plot analysis. It was found that the binding sites of glucose transporter in plasma membrane and intracellular membrane were 5.6 nmol 14C-glucose/mg protein and 8.7 nmol 14C-glucose-mg protein respectively at basic state. Insulin treatment in experimental groups caused approximately 146% increase in plasma membrane fraction and 88% decrease in intracellular membrane fraction. Moreover, the kinetic data of Scatchard plot curve were similar to those of the [3H]-cytochalasin B binding assay. D-[U-14C] glucose binding assay of glucose transporter binding sites in muscular cell membrane is simple, easy and practicable. The D-[U-14C] glucose is commercially available

  1. Fate of 14C-gamma-HCH in rice and its processed products

    International Nuclear Information System (INIS)

    Rice plants were treated at the rate of 2.5 kg AI/ha with 10% HCH dust containing 14C-gamma-HCH. At harvest, the terminal residues (gamma-HCH) were 0.026 mg/kg and 0.042 mg/kg in rice grain and husk, respectively. Rice bran contained 0.187 mg/kg of which 0.129 mg/kg was present in oil. In a laboratory experiment, crude rice bran oil was fortified with 14C-gamma-HCH at 0.1 mg/kg and the fate of the pesticide was followed in the oil during simulated commercial refining procedures. While degumming, dewaxing, alkali treatment and bleaching had not effect, deodorization alone removed 99.5% of 14C-residues from the oil. The rice-black gram dough used for preparing the local rice cake was fortified with 14C-gamma-HCH (1 mg/kg) and the residues were monitored through the fermentation and cooking processes. It was found that there was no loss of residues during fermentation of the dough, while steaming removed 24% of the 14C-residue. (author). (Abstract only)

  2. Decomposition of /sup 14/C-labelled lignin, holocellulose and lignocellulose by mycorrhizal fungi

    Energy Technology Data Exchange (ETDEWEB)

    Trojanowski, J.; Huettermann, A.; Haider, K.

    1984-01-01

    Five different species of known ecto-mycorrhizal fungi: Cenococcum geophilum, Amanita muscaria, Tricholoma aurantium, Rhizopogon luteolus and Rhizopogon roseolus were studied for their ability to metabolize the major components of plant cell walls. All strains were able to decompose /sup 14/C-labelled plant lignin, /sup 14/C-lignocellulose and /sup 14/C-DHP-lignin at a rate which was lower than the one observed for the known white rot fungi Heterobasidion annosum and Sporotrichum pulverulentum. Also /sup 14/C-(U)-holocellulose was relatively less degradable for the mycorrhizal fungi than for the white rotters. On the other hand, aromatic monomers like /sup 14/C-vanillic acid were decomposed to a much higher extent by two species of mycorrhizal fungi compared to the activity observed for Heterobasidion annosum. The results of the experiments reveal that these stains of mycorrhizal fungi are well able to utilize the major components of plant material and thus can contribute to litter decomposition in the forest floor.

  3. Variations of 14-C around AD 775 and AD 1795 - due to solar activity

    CERN Document Server

    Neuhaeuser, Ralph

    2015-01-01

    The motivation for our study is the disputed cause for the strong variation of 14-C around AD 775. Our method is to compare the 14-C variation around AD 775 with other periods of strong variability. Our results are: (a) We see three periods, where 14-C varied over 200 yr in a special way showing a certain pattern of strong secular variation: after a Grand Minimum with strongly increasing 14-C, there is a series of strong short-term drop(s), rise(s), and again drop(s) within 60 yr, ending up to 200 yr after the start of the Grand Minimum. These three periods include the strong rises around BC 671, AD 775, and AD 1795. (b) We show with several solar activity proxies (radioisotopes, sunspots, and aurorae) for the AD 770s and 1790s that such intense rapid 14-C increases can be explained by strong rapid decreases in solar activity and, hence, wind, so that the decrease in solar modulation potential leads to an increase in radioisotope production. (c) The strong rises around AD 775 and 1795 are due to three effects...

  4. Modulation of (14) C-labeled glucose metabolism by zinc during aluminium induced neurodegeneration.

    Science.gov (United States)

    Singla, Neha; Dhawan, D K

    2015-09-01

    Aluminium (Al) is one of the most prominent metals in the environment and is responsible for causing several neurological disorders, including Alzheimer's disease. On the other hand, zinc (Zn) is an essential micronutrient that is involved in regulating brain development and function. The present study investigates the protective potential of Zn in the uptake of (14) C-labeled amino acids and glucose and their turnover in rat brain slices during Al intoxication. Male Sprague Dawley rats (140-160 g) were divided into four different groups: normal control, Al treated (100 mg/kg body weight/day via oral gavage), Zn treated (227 mg/liter in drinking water), and Al + Zn treated. Radiorespirometric assay revealed an increase in glucose turnover after Al exposure that was attenuated after Zn treatment. Furthermore, the uptake of (14) C-labeled glucose was increased after Al treatment but was appreciably decreased upon Zn supplementation. In addition, the uptakes of (14) C-lysine, (14) C-leucine, and (14) C-aspartic acid were also found to be elevated following Al exposure but were decreased after Zn treatment. Al treatment also caused alterations in the neurohistoarchitecture of the brain, which were improved after Zn coadministration. Therefore, the present study suggests that Zn provides protection against Al-induced neurotoxicity by regulating glucose and amino acid uptake in rats, indicating that Zn could be a potential candidate for the treatment of various neurodegenerative disorders. PMID:25908409

  5. Influence of pesticide applications on degradation of the herbicide 14C - 2,4-D in different soils

    International Nuclear Information System (INIS)

    Despite the importance of pesticide usage for the food production, its indiscriminate use may cause changes in the soil fertility, because pesticides influence soil microorganisms which are important for the biogeochemical cycles. The influence of applications of several pesticides, as recommended for cotton culture, was studied on the bioactivity of different soils (from Sao Paulo and Tatui, SP) by using radiometric techniques and a closed system for detection of bio mineralization of ''14C-2,4-D (14C-2,4-dichlorophenoxyacetic acid) and production of 14C-volatile compounds. The 14C-2,4-D dissipation under influence of other pesticide applications was also studied by determination of 14C-extractable residues, 14C-bound residues and qualitative and quantitative analysis of the 14C-extractable residues by high pressure liquid chromatography (HPLC) and thin layer chromatography (TLC). 14C-volatile compounds were never detected but increases and decreases of bio mineralization were detected in both soils after different treatments. The mixture of deltamethrin + methyl parathion increased significantly the bioactivity in both soils; nevertheless, monocrotophos did not have any influence. The applications of different pesticides have also influenced the 14C-2,4-D dissipation, because the radiocarbon recovered as 14C-extractable residues differed between the treated and untreated samples of both soils. On the other hand, the pesticide applications did not influence the production of 14C-bound residues. This 14C-residue was produced in larger amounts by the richest in organic matter soil (Sao Paulo). Although radiocarbon had been detected not only as 14'C-2,4-D but also as a 14C-metabolite, in both soils and treatments, results indicate that the '14C-2,4-D dissipation varied in the two studied soils and was influenced by treatments with others pesticides. (author)

  6. Validation of 14 C-urea breath test for diagnosis of Helicobacter pylori

    International Nuclear Information System (INIS)

    The aim of this study was to validate the 14 C-urea breath test for use in diagnosis of Helicobacter pylori infection. Thirty H. pylori positive patients, based on histologic test and thirty H. pylori negative patients by histology and anti-H pylori IgG entered the study. Fasting patients drank 5 uCi of 14 C-urea in 20 ml of water. Breath samples were collected at O, 5, 10, 15, 20 and 30 min. The difference of cpm values between the two groups was significant at all the time intervals, besides time 0 (p 14 C-urea breath test is highly accurate for Helicobacter pylori diagnosis. It is fast, simple and should be the non-invasive test used after treating Helicobacter pylori infection. (author)

  7. 14C Activity and Global Carbon Cycle Changes over the Past 50,000 Years

    Science.gov (United States)

    Hughen, K.; Lehman, S.; Southon, J.; Overpeck, J.; Marchal, O.; Herring, C.; Turnbull, J.

    2004-01-01

    A series of 14C measurements in Ocean Drilling Program cores from the tropical Cariaco Basin, which have been correlated to the annual-layer counted chronology for the Greenland Ice Sheet Project 2 (GISP2) ice core, provides a high-resolution calibration of the radiocarbon time scale back to 50,000 years before the present. Independent radiometric dating of events correlated to GISP2 suggests that the calibration is accurate. Reconstructed 14C activities varied substantially during the last glacial period, including sharp peaks synchronous with the Laschamp and Mono Lake geomagnetic field intensity minimal and cosmogenic nuclide peaks in ice cores and marine sediments. Simulations with a geochemical box model suggest that much of the variability can be explained by geomagnetically modulated changes in 14C production rate together with plausible changes in deep-ocean ventilation and the global carbon cycle during glaciation.

  8. Biosynthesis of 14C-labelled erucic acid by means of rape plants

    International Nuclear Information System (INIS)

    For the biosynthetic preparation of 14C-erucic adid (C21H41COOH) by means of rape plants cv. sollux the plants were supplied with 14CO2 and additionally fed with 14C-Sodium acetate after anthesis. After saponification of the extracted lipids the erucic acid was isolated and purified. The substance was identified by gas chromatography. The incorporation of the applied radioactive (34 MBq 14CO2; 37 MBq 14C-natrium acetate) into the fatty acids amounted to 1,2 per cent. The erucic acid could be isolated from the fatty acids mixture with a specific radioactivity of 1,001 MBq/mmol and a purity of 97,2 per cent. (orig.)

  9. Differences in [14C]glycerol utilization in normal and familial hypercholesterolemic fibroblasts

    International Nuclear Information System (INIS)

    It is known that cultured fibroblasts from familial hypercholesterolemia (FH) patients lack the normal cell receptor for low density lipoprotein (LDL) and that the absence of receptor-mediated transport of LDL cholesterol into these cells results in increased cellular synthesis of cholesterol. After 20 h perincubation in lipid-free medium, cultured FH fibroblasts incorporated significantly greater amounts of [14C]glycerol into cellular lipids than did normal fibroblasts. Relative to the control medium which contained only bovine serum albumin (BSA), preincubation with 5% fetal bovine serum or 50 micrograms LDL/ml decreased [14C]glycerol incorporation by both cell types. FH cells utilized more [14C]glycerol for phospholipid synthesis and less for triglyceride synthesis than normal cells. This study indicates that LDL may be important in the transport of glycerides, as well as cholesterol, to cells

  10. Distribution of 14C-TNT and derivatives in different biochemical compartments of Phaseolus vulgaris.

    Science.gov (United States)

    Sens, C; Scheidemann, P; Klunk, A; Werner, D

    1998-01-01

    (14)C-TNT was used to quantify the uptake rate and metabolic turnover of TNT in Phaseolus vulgaris. Seventeen plants were analysed by a special cell fractionation method with polar and nonpolar solvents and enzymes. We obtained three cytoplasmic fractions and five cell wall derived fractions. The recovery rate was 72% as measured by liquid scintillation counting. (14)C partitioned almost in equal amounts with approximately 50% in the cytoplasm and in the cell wall. The majority of the TNT-metabolites are present in the cytoplasm as was shown by GC/ECD and thin layer chromatography. The(14)C in the cell wall is bound probably resulting in long-term immobilisation of these metabolites. We conclude that plants may also be a model for nitroaromatic turnover and immobilisation in soil components. PMID:19002633

  11. Variation of 14C, 137Cs and stable carbon composition in forest soil and its implications

    International Nuclear Information System (INIS)

    In Japan, about 70% of land area is covered by forest. Therefore, forest ecosystem plays a vital role in ultimate fate of radionuclides and carbon cycle in terrestrial environment. Three undisturbed forest soil profiles were collected from Ibaraki Prefecture, Japan. The 137Cs data illustrate that maximum fallout deposition of 137Cs took place around 1964. 14C determination shows that 14C also has peak values in the top 10 cm of the soil profiles ascribed to the highest bomb 14C level in 1960's. The 13C data show that the turnover dynamics of soil organic carbon could be described very well by progressive enrichment values of δ13C. (author)

  12. Preparation of 14C-Labeled Multi-walled Carbon Nano-tubes for Biodistribution Investigations

    International Nuclear Information System (INIS)

    A new method allowing the 14C-labeling of carboxylic acid functions of carbon nano-tubes is described. The key step of the labeling process is a de-carbonylation reaction that has been developed and optimized with the help of a screening method. The optimized process has been successfully applied to multi-walled carbon nano-tubes (MWNTs), and the corresponding 14C-labeled nano-tubes were used to investigate their in vivo behavior. Preliminary results obtained after i.v. contamination of rats revealed liver as the main target organ. Radiolabeling of NTs with a long-life radioactive nucleus like 14C, coupled to a highly sensitive autoradiographic method, that provides a unique detection threshold, will make it possible to determine for a long time period whether or not NTs remain in any organs after animal exposure. (authors)

  13. Effect of commercial processing procedures on 14C-LINDANE residues in corn oil

    International Nuclear Information System (INIS)

    At blooming, maize plants were sprayed twice, 23 days apart, at a dose of 22 mg equivalent to 5 μCi/ plant. At post harvest, maize seeds had a radioactivity corresponding to 0.36% of the applied dose. The insecticide residues in crude oil, cake and methanolic extract were amounted to 8 % and 60 % 5 % , respectively, of original residues inside the seeds.The 14C-activity in the crude oil could be reduced by commercial processes locally used for refining. The refined oil had a residue level of about 0.7 ppm mainly in the form of unchanged lindane in addition to a number of chloro phenols as main metabolites. Refining of corn oil fortified with 14C-lindane led to a high reduction of 14C-lindane (88%). The refined oil contained a residue consisting lindane and its chloro phenols

  14. Differences in ( sup 14 C)glycerol utilization in normal and familial hypercholesterolemic fibroblasts

    Energy Technology Data Exchange (ETDEWEB)

    Shireman, R.B.; Durieux, J. (Univ. of Florida Gainesville (USA))

    1991-01-01

    It is known that cultured fibroblasts from familial hypercholesterolemia (FH) patients lack the normal cell receptor for low density lipoprotein (LDL) and that the absence of receptor-mediated transport of LDL cholesterol into these cells results in increased cellular synthesis of cholesterol. After 20 h perincubation in lipid-free medium, cultured FH fibroblasts incorporated significantly greater amounts of ({sup 14}C)glycerol into cellular lipids than did normal fibroblasts. Relative to the control medium which contained only bovine serum albumin (BSA), preincubation with 5% fetal bovine serum or 50 micrograms LDL/ml decreased ({sup 14}C)glycerol incorporation by both cell types. FH cells utilized more ({sup 14}C)glycerol for phospholipid synthesis and less for triglyceride synthesis than normal cells. This study indicates that LDL may be important in the transport of glycerides, as well as cholesterol, to cells.

  15. Application and detection of (14)c-hd in two mouse models.

    Science.gov (United States)

    Logan, Thomas P; Shutz, Michael; Schulz, Susan M; Railer, Roy; Ricketts, Karen M; Casillas, Robert P

    2002-01-01

    The CD1-haired mouse and the SKH-hairless mouse are two animal models that have been used to evaluate sulfur mustard (HD) exposure and protection in our laboratory. In a recent study we observed that a substance P inhibitor protected the haired mouse ear against an HD solution, but the same drug was not successful in protecting the hairless mouse against HD vapor. This experiment prompted us to compare HD exposures between these models. We determined the (14)C content in the skin after exposures to HD containing (14)C-HD. Rate curves were generated for applications of (1) HD in methylene chloride to the haired mouse ear; (2) HD in methylene chloride to the hairless mouse dorsal skin; and (3) saturated HD vapor to the hairless mouse dorsal skin for 6 min. The curves showed a reduction in (14)C disintegrations per min in animals euthanized 0 to 2 h postexposure. The largest percentage of decrease of (14)C content in skin occurred within 30 min of HD challenge for all exposures. An 8-mm skin-punch biopsy and a 14-mm annular skin section surrounding the region of the 8-mm skin punch were taken from the hairless mouse dorsal skin exposed to HD in methylene chloride. The ratio of the (14)C content in the 8-mm skin punch to that in the surrounding 14-mm annular skin section was 7.3, demonstrating that the HD application spreads beyond the initially biopsied site. A concentration/time value of 6.3 mug/cm(2)/min was determined by counting skin (14)C disintegrations per minute in animals euthanized immediately after exposure to saturated HD vapor. Determinations of the amount of HD showed that similar quantities of HD, 0.4 mg, were detected on each model. These results contribute to a better quantitative understanding of HD application in the haired and hairless mouse models.

  16. Effect of foliar treatments on distribution of 14C-glyphosate in Convolvulus arvensis L

    International Nuclear Information System (INIS)

    Field bindweed is a perennial weed which produces shoots from buds on its roots. Herbicides, such as glyphosate [N-(phosphonomethyl)glycine] used for control of field bindweed usually do not kill all shoot buds on the roots, thus field bindweed often reinfests areas within 3 to 6 weeks of treatment. This dissertation deals with the development of a technique to change glyphosate distribution in field bindweed roots and could result in less shoot regrowth after glyphosate application. In field studies eight plant growth regulators were applied in September, 3 days before 2.24 kg/ha of 2.4-D[(2,4-dichlorophenoxy) acetic acid] or 1.68 kg/ha of glyphosate. Eight months later, regrowth of shoots was least where glyphosate was applied at 0.028 kg/ha as a pretreatment, followed by a standard rate of 1.68 kg/ha. In subsequent greenhouse studies, typical patterns of shoot growth and 14C-glyphosate distribution in isolated root sections taken from 15-week-old intact plants were determined. In subsequent growth chamber studies, plants were decapitated to observe the effect of shoot apical dominance on 14C-glyphosate translocation. After 14C-glyphosate was applied, intact plants had about twice as much 14C in distal root sections as in proximal or middle root sections. Decapitated plants had more 14C in proximal and middle root sections than in distal sections, and about twice as much 14C was translocated to roots of decapitated plants than intact plants. Eight concentrations of 2,4,-D or glyphosate from 1 to 5000 ppm were applied in logarithmic series to 6-week old plants

  17. Study of a nuclear graphite waste 14C decontamination process by CO2 gasification

    International Nuclear Information System (INIS)

    The decommissioning of French gas cooled nuclear reactors (UNGG), all arrested since 1994, will generate 23,000 tons of graphite waste classified Low Level and Long Lived and notably containing 14C. The aim of this thesis is to study a new method for selective extraction of this radionuclide by CO2 gasification.The multi-scale organization of virgin and irradiated graphite has been studied by a coupling between microspectrometry Raman and transmission electron microscopy. With the neutron fluence, the structure degrades and the nano-structure can be greatly changed. In extreme cases, the lamellar nano-structure nuclear graphite has become nano-porous. Furthermore, these damages are systematically heterogeneous. An orientation effect of 'crystallites', shown experimentally by ion implantation, could be a cause of these heterogeneities.This study also showed that from a specific fluence, there is an important development of nano-porous zones coinciding with a dramatic 14C concentration increase. This radionuclide could be preferentially concentrated in the nano-porous areas which are potentially more reactive than the remaining laminar areas which could be less rich in 14C. This process by CO2 gasification was firstly tested on 'analogous' non-radioactive materials (mechanically milled graphite). These tests confirmed, for temperatures between 950 and 1000 C, the selective and complete elimination of nano-porous areas.Tests were then carried out on graphite waste from Saint-Laurent-des-Eaux A2 and G2 reactors. The results are promising with notably the quarter of 14C inventory extracted for a weight loss of only few percent. Up to 68 % of 14C inventory was extracted, but with an important gasification. Thus, this treatment could allow extracting selectively a share of 14C inventory (mobile or linked to nano-porous areas) and allows imagining alternative scenarios for graphite waste managing. (author)

  18. Carbon and 14C distribution in tropical and subtropical agricultural soils

    Science.gov (United States)

    Prastowo, Erwin; Grootes, Pieter; Nadeau, Marie

    2016-04-01

    Paddy soil management affects, through the alternating anoxic and oxic conditions it creates, the transport and stabilisation of soil organic matter (SOM). Irrigation water may percolate more organic materials - dissolved (DOM) and colloidal - into the subsoil during anoxic conditions. Yet a developed ploughpan tends to prevent C from going deeper in the subsoil and partly decouple C distribution in top and sub soil. We investigate the influence of different soil type and environment. We observed the C and 14C distribution in paddy and non-paddy soil profiles in three different soil types from four different climatic regions of tropical Indonesia, and subtropical China. Locations were Sukabumi (Andosol, ca. 850 m a.s.l), Bogor (clayey Alisol, ca. 240 m a.s.l), and Ngawi (Vertisol, ca. 70 m a.s.l) in Jawa, Indonesia, and Cixi (Alisol(sandy), ca. 4 - 6 m a.s.l) in Zhejiang Province, China. We compared rice paddies with selected neighbouring non-paddy fields and employed AMS 14C as a tool to study C dynamics from bulk, alkali soluble-humic, and insoluble humin samples, and macrofossils (plant remains, charcoal). Our data suggest that vegetation type determines the quantity and quality of biomass introduced as litter and root material in top and subsoil, and thus contributes to the soil C content and profile, which fits the 14C signal distribution, as well as 13C in Ngawi with C4 sugar cane as upland crop. 14C concentrations for the mobile humic acid fraction were generally higher than for bulk samples from the same depth, except when recent plant and root debris led to high 14C levels in near-surface samples. The difference in sampling, - averaged layer for bulk sample and 1-cm layer thickness for point sample - shows gradients in C and 14C across the layers, which could be a reason for discrepancies between the two. High 14C concentrations - in Andosol Sukabumi up to 111 pMC - exceed the atmospheric 14CO2concentration in the sampling year in 2012 (˜ 103 pMC) and

  19. A rapid phospholipase A2 bioassay using 14C-oleate-labelled E. coli bacterias.

    Science.gov (United States)

    Meyer, T; von Wichert, P; Weins, D

    1989-02-01

    Two methods of phospholipase A2 determination using 14C-labelled E. coli bacterias as substrate were compared. One method works with a filter membrane for separation of cleaved 14C-oleate from remaining phospholipids, the other uses the well-known thin-layer chromatography for lipid analysis. Some features of human serum phospholipase A2 regarding pH and Ca2+ dependency were investigated. Possible sources of errors were discussed. It was shown that either method can differentiate between normal and pathologically elevated phospholipase A2 levels, but that the filter method is superior in terms of sensitivity and workload.

  20. Modelling of dead carbon fraction in speleothems: a step towards reliable speleothem 14C-chronologies

    Science.gov (United States)

    Lechleitner, Franziska A.; Jamieson, Robert A.; McIntyre, Cameron; Baldini, Lisa M.; Baldini, James U. L.; Eglinton, Timothy I.

    2015-04-01

    Over the past two decades, speleothems have become one of the most versatile and promising archives for the study of past continental climate. Very precise absolute dating is often possible using the U-Th method, resulting in paleoclimate records of exceptional resolution and accuracy. However, not all speleothems are amenable to this dating method for a variety of reasons (e.g. low U concentrations, high detrital Th etc). This has lead researchers to exclude many otherwise suitable speleothems and cave sites from further investigation. 14C-dating of speleothems has so far not been applicable, due to the 'dead carbon' problem. As drip water percolates through the karst, dissolving CaCO3, a variable amount of 14C-dead carbon is added to the solution. This results in a temporally variable and site-specific reservoir effect, ultimately undermining the development of speleothem 14C -chronologies. However, a number of recent studies have shown a clear link between karst hydrology and associated proxies (e.g., Mg/Ca and δ13C) and this 'dead carbon fraction' (DCF). We take advantage of this relationship to model DCF and its changes using Mg/Ca, δ13C and 14C data from published speleothem records. Using one record for calibration purposes, we build a transfer function for the DCF in relation to δ13C and Mg/Ca, which we then apply to other 14C records. Initial model results are promising; we are able to reconstruct general long-term average DCF within uncertainties of the calculated DCF from the U-Th chronology. Large shifts in DCF related to hydrology are also often detected. In a second step, we apply the model to a speleothem from southern Poland, which so far could not be dated, due to very low U-concentrations. To construct a 14C chronology, the stalagmite was sampled at 5 mm intervals. CaCO3 powders were graphitized and measured by Accelerator Mass Spectrometry (MICADAS) at ETH Zurich. Additional high-resolution (0.1 mm/sample) 14C measurements were performed on

  1. Distribution of /sup 14/C-labelled ochratoxin A in pregnant mice

    Energy Technology Data Exchange (ETDEWEB)

    Appelgren, L.E.; Arora, R.G.

    1983-10-01

    Autoradiography was used to study the distribution of /sup 14/C-labelled ochratoxin A for up to 4 hr after its iv administration to mice at various stages of pregnancy. The highest /sup 14/C concentration was consistently found in the bile throughout the experimental period. The concentration of radioactivity in the tissues was found, in decreasing order, in the liver, kidney, blood, salivary glands, large vessels, brown fat, myocardium, uterus and lymphatic tissues. The toxin was shown to cross the placental barrier on day 9 of pregnancy, at which time it is most effective in producing fetal malformations.

  2. Analysis of 14C-Urea breath test in patients with halitosis

    International Nuclear Information System (INIS)

    Objective: To explore the relationship between halitosis and the infection of helicobacter pylori (HP). Methods: The results of 14C-urea breath test of 59 normal people, 50 patients with halitosis only and 56 patients infected by both halitosis and digestive diseases were analyzed. Results: It showed that the 14C content and HP positive rate in group infected by both halitosis and digestive diseases were much higher than that of halitosis only group and normal people group (P<0.05). Conclusion: The infection of Helicobacter pylori is an important factor but not only factor of halitosis. (authors)

  3. A study of placental transfer mechanisms in nonhuman primates using [14C]phenylalanine

    International Nuclear Information System (INIS)

    Placental transfer mechanisms were investigated in pregnant Macaca Fascicularis and Macaca mulatta during the gestational age of 120 to 130 days. These primates underwent an operative procedure that allowed continuous fetal blood sampling. The administration of [14C]phenylalanine into the maternal circulation revealed a significant increase of radioactive material in the fetal circulation, indicating an active placental transport mechanism unidirectional to the fetus. When [14C]phenylalanine was injected into the fetus, radioactive aromatic amino acids in the maternal circulation increased only slightly over time, resembling a simple diffusion process

  4. Variations of 14C around AD 775 and AD 1795 - due to solar activity

    Science.gov (United States)

    Neuhäuser, R.; Neuhäuser, D. L.

    2015-12-01

    The motivation for our study is the disputed cause for the strong variation of 14C around AD 775. Our method is to compare the 14C variation around AD 775 with other periods of strong variability. Our results are: (a) We see three periods, where 14C varied over 200 yr in a special way showing a certain pattern of strong secular variation: after a Grand Minimum with strongly increasing 14C, there is a series of strong short-term drop(s), rise(s), and again drop(s) within 60 yr, ending up to 200 yr after the start of the Grand Minimum. These three periods include the strong rises around BC 671, AD 775, and AD 1795. (b) We show with several solar activity proxies (radioisotopes, sunspots, and aurorae) for the AD 770s and 1790s that such intense rapid 14C increases can be explained by strong rapid decreases in solar activity and, hence, wind, so that the decrease in solar modulation potential leads to an increase in radioisotope production. (c) The strong rises around AD 775 and 1795 are due to three effects, (i) very strong activity in the previous cycles (i.e. very low 14C level), (ii) the declining phase of a very strong Schwabe cycle, and (iii) a phase of very weak activity after the strong 14C rise - very short and/or weak cycle(s) like the suddenly starting Dalton minimum. (d) Furthermore, we can show that the strong change at AD 1795 happened after a pair of two packages of four Schwabe cycles with certain hemispheric leadership (each package consists of two Gnevyshev-Ohl pairs, respectively two Hale-Babcock pairs). We show with several additional arguments that the rise around AD 775 was not that special. We conclude that such large, short-term rises in 14C (around BC 671, AD 775, and 1795) do not need to be explained by highly unlikely solar super-flares nor other rare events, but by extra-solar cosmic rays modulated due to solar activity variations.

  5. Determination of 14C-labeled plasma L + α-alanine specific radioactivity

    International Nuclear Information System (INIS)

    A method is described, which enables the specific radioactivity of 14C-labeled L + α-alanine in plasma to be determined. Plasma alanine concentration is determined spectrophotometrically using alanine dehydrogenase. In a separate procedure, this enzyme is also used to convert 14C labeled alanine and added carrier alanine, to pyruvate. The phenylhydrazone derivative of the pyruvate is then prepared and assayed for radioactivity after crystallization to constant specific radioactivity. A maximum error of 1.5 percent for any one specific radioactivity determination was found. (U.S.)

  6. II. The effect of microbial activity on the stability of 14C-coumaphos

    International Nuclear Information System (INIS)

    The effects of sediment adsorption and microbial activity on the stability of 14C-coumaphos in a water+sediment system was studied by quantifying mineralization, distribution between water and sediment phases and binding to sediment. Mineralization of Coumaphos slowly increased with time but it decreased slightly with an increase in sediment content. Incubation of non-sterilized and sterilized water+sediment systems treated with 14C-coumaphos for 12 weeks resulted in losses up to 14% in non-sterile treatments. Most of the added radioactivity was found in the sediment. The extractable residues (60%) contained mainly coumaphos and chlorferone. (author)

  7. Nuclear structure effects in the exotic decay of $^{225}$Ac via $^{14}$C emission

    CERN Document Server

    Bonetti, R; Guglielmetti, A; Matheoud, R; Migliorino, C; Pasinetti, A L; Ravn, H L

    1993-01-01

    By using a $^{225}$Ac source produced at the electromagnetic separator Isolde we collected on our track-recording glass detectors 305 $^{14}$C events from the radioactive decays of $^{225}$Ac and its daughter $^{221}$Fr and obtained, for $^{225}$Ac, a branching ratio B($^{14}$C/$\\alpha$)=(6.0 $\\pm$ 1.3) x 10$^{-12}$. Our result suggests that such a decay from an odd proton nucleus is dominated by transition to the ground or to the first excited state of daughter nucleus.

  8. Radiocarbon analysis of the EPICA Dome C ice core: no in situ 14C from the firn observed

    International Nuclear Information System (INIS)

    CO2 and CO obtained by dry-extraction from ice samples of the EPICA Dome C core were 14C analysed by AMS. For some of the ice samples there is no evidence for in situ 14C, indicating the firn did not retain 14C. The 14C ages of these samples are too old in comparison with a calibrated ice-flow model, and the concentrations of 14CO are near zero. For other ice samples, however, in situ 14C is clearly present, and is likely from post-coring exposure at the Dome C surface. These samples show too young 14C ages, and distinct concentrations of 14CO. The accuracy of ages obtained from 14C analysis of ice samples is discussed

  9. Development and Validation of a P-35S, T-nos, T-35S and P-FMV Tetraplex Real-time PCR Screening Method to Detect Regulatory Genes of Genetically Modified Organisms in Food.

    Science.gov (United States)

    Eugster, Albert; Murmann, Petra; Kaenzig, Andre; Breitenmoser, Alda

    2014-10-01

    In routine analysis screening methods based on real-time PCR (polymerase chain reaction) are most commonly used for the detection of genetically modified (GM) plant material in food and feed. Screening tests are based on sequences frequently used for GM development, allowing the detection of a large number of GMOs (genetically modified organisms). Here, we describe the development and validation of a tetraplex real-time PCR screening assay comprising detection systems for the regulatory genes Cauliflower Mosaic Virus 35S promoter, Agrobacterium tumefaciens nos terminator, Cauliflower Mosaic Virus 35S terminator and Figwort Mosaic Virus 34S promoter. Three of the four primer and probe combinations have already been published elsewhere, whereas primers and probe for the 35S terminator have been developed in-house. Adjustment of primer and probe concentrations revealed a high PCR sensitivity with insignificant physical cross-talk between the four detection channels. The sensitivity of each PCR-system is sufficient to detect a GMO concentration as low as 0.05% of the containing respective element. The specificity of the described tetraplex is high when tested on DNA from GM maize, soy, rapeseed and tomato. We also demonstrate the robustness of the system by inter-laboratory tests. In conclusion, this method provides a sensitive and reliable screening procedure for the detection of the most frequently used regulatory elements present in GM crops either authorised or unauthorised for food.

  10. Development and Validation of a P-35S, T-nos, T-35S and P-FMV Tetraplex Real-time PCR Screening Method to Detect Regulatory Genes of Genetically Modified Organisms in Food.

    Science.gov (United States)

    Eugster, Albert; Murmann, Petra; Kaenzig, Andre; Breitenmoser, Alda

    2014-10-01

    In routine analysis screening methods based on real-time PCR (polymerase chain reaction) are most commonly used for the detection of genetically modified (GM) plant material in food and feed. Screening tests are based on sequences frequently used for GM development, allowing the detection of a large number of GMOs (genetically modified organisms). Here, we describe the development and validation of a tetraplex real-time PCR screening assay comprising detection systems for the regulatory genes Cauliflower Mosaic Virus 35S promoter, Agrobacterium tumefaciens nos terminator, Cauliflower Mosaic Virus 35S terminator and Figwort Mosaic Virus 34S promoter. Three of the four primer and probe combinations have already been published elsewhere, whereas primers and probe for the 35S terminator have been developed in-house. Adjustment of primer and probe concentrations revealed a high PCR sensitivity with insignificant physical cross-talk between the four detection channels. The sensitivity of each PCR-system is sufficient to detect a GMO concentration as low as 0.05% of the containing respective element. The specificity of the described tetraplex is high when tested on DNA from GM maize, soy, rapeseed and tomato. We also demonstrate the robustness of the system by inter-laboratory tests. In conclusion, this method provides a sensitive and reliable screening procedure for the detection of the most frequently used regulatory elements present in GM crops either authorised or unauthorised for food. PMID:25437161

  11. Determination of proline and hydroxyproline in wheat flour by spectrophotometry and measurement of radioactivity of proline-/sup 14/C and hydroxyproline-/sup 14/C

    Energy Technology Data Exchange (ETDEWEB)

    Nicolas, A.; Trifone, A.; Delgado, L.N.; Nassiff, S.J. (Comision Nacional de Energia Atomica, Buenos Aires (Argentina))

    1984-05-07

    Proline and hydroxyproline are two amino acids which, due to their analogous chemical structures, give similar reactions and often appear together. In view of the high percentage of proline in wheat gluten, the presence of hydroxyproline in wheat flour was investigated. A method was developed to separate the two amino acids after separation from other interfering amino acids which are present in flour. The method of separation utilizes an ion-exchange column (Dowex 50 X-8, 100-100 resin). The separated amino acids are determined either by spectrophotometry or isotope dilution (/sup 14/C). The latter is more rapid and more sensitive than the spectrophotometric method. 13 refs.

  12. Distribution of root exudates and mucilage in the rhizosphere: combining 14C imaging with neutron radiography

    Science.gov (United States)

    Holz, Maire; Carminati, Andrea; Kuzyakov, Yakov

    2015-04-01

    Water and nutrients will be the major factors limiting food production in future. Plant roots employ various mechanisms to increase the access to limited soil resources. Low molecular weight organic substances released by roots into the rhizosphere increase nutrient availability by interactions with microorganisms, while mucilage improves water availability under low moisture conditions. Though composition and quality of these substances have intensively been investigated, studies on the spatial distribution and quantification of exudates in soil are scarce. Our aim was to quantify and visualize root exudates and mucilage distribution around growing roots using neutron radiography and 14C imaging depending on drought stress. Plants were grown in rhizotrons well suited for neutron radiography and 14C imaging. Plants were exposed to various soil water contents experiencing different levels of drought stress. The water content in the rhizosphere was imaged during several drying/wetting cycles by neutron radiography. The radiographs taken a few hours after irrigation showed a wet region around the root tips showing the allocation and distribution of mucilage. The increased water content in the rhizosphere of the young root segments was related to mucilage concentrations by parameterization described in Kroener et al. (2014). In parallel 14C imaging of root after 14CO2 labeling of shoots (Pausch and Kuzyakov 2011) showed distribution of rhizodeposits including mucilage. Three days after setting the water content, plants were labeled in 14CO2 atmosphere. Two days later 14C distribution in soil was imaged by placing a phosphor-imaging plate on the rhizobox. To quantify rhizodeposition, 14C activity on the image was related to the absolute 14C activity in the soil and root after destructive sampling. By comparing the amounts of mucilage (neutron radiography) with the amount of total root derived C (14C imaging), we were able to differentiate between mucilage and root

  13. Effect of salseed-meal tannins on protein synthesis, 35S incorporation and cellulose digestibility by rumen microbes in vitro

    International Nuclear Information System (INIS)

    Tannins from seed-meal of sal (Shorea robusta Gaertn. F.) were fractionated after treatments into ethyl acetate (EA) and lead acetate (LA) fractions. In trial 1, incorporation of 35S from (NH4)235SO4 into microbial protein declined due to the effect of both 2% EA and LA fractions as compared to control. Microbial protein synthesis was depressed significantly (P 35S incorporation and cellulolysis at all levels of both the tannin fractions. It may be inferred that both the tannin fractions from salseed-meal showed antimicrobial activity and LA fraction seems to be more deleterious than EA fraction for rumen metabolism. The experiments were conducted in vitro using rumen liquor of a non-pregnant dry cow having permanent rumen fistula. (auth.)

  14. Detection of viral genomes in the liver by in situ hybridization using 35S-, bromodeoxyuridine-, and biotin-labeled probes

    International Nuclear Information System (INIS)

    Methods employing 35S-, biotin-, and bromodeoxyuridine (BrdUrd)-labeled DNA probes were compared for the detection of hepatitis B virus (HBV) and cytomegalovirus (CMV) in the liver. The results demonstrate that: 1) HBV can be detected reliably only by the use of radiolabeled probes, whereas methods employing nonradioactive probes obviously are not sensitive enough for this virus. The use of 35S-labeled probes shortens the exposure times considerably in comparison to tritiated probes. 2) Biotin-labeled probes are of limited value for in situ hybridization on liver tissues because the presence of endogenous avidin-binding activity often leads to false positive results. 3) Brd-Urd-labeled probes are a useful alternative to biotinylated probes for the detection of CMV. In comparison with biotinylated probes, BrdUrd-labeled probes produce a specific signal of similar staining intensity in the absence of background staining in the liver

  15. Method for the typing of Clostridium difficile based on polyacrylamide gel electrophoresis of [35S]methionine-labeled proteins

    International Nuclear Information System (INIS)

    A typing method for Clostridium difficile based on the incorporation of [35S]methionine into cellular proteins, their separation by sodium dodecyl sulfate-polyacrylamide gel electrophoresis, and their visualization by autoradiography is described. On analysis of the radiolabeled-protein profiles, nine distinct groups were observed (A to E and W to Z). The method, which is simple, reproducible, and readily expandable, has been applied in epidemiological studies to demonstrate cross-infection and hospital acquisition of C. difficile

  16. Method for the typing of Clostridium difficile based on polyacrylamide gel electrophoresis of (/sup 35/S)methionine-labeled proteins

    Energy Technology Data Exchange (ETDEWEB)

    Tabaqchali, S.; O' Farrell, S.; Holland, D.; Silman, R.

    1986-01-01

    A typing method for Clostridium difficile based on the incorporation of (/sup 35/S)methionine into cellular proteins, their separation by sodium dodecyl sulfate-polyacrylamide gel electrophoresis, and their visualization by autoradiography is described. On analysis of the radiolabeled-protein profiles, nine distinct groups were observed (A to E and W to Z). The method, which is simple, reproducible, and readily expandable, has been applied in epidemiological studies to demonstrate cross-infection and hospital acquisition of C. difficile.

  17. Fate of organochlorine 14C-dicofol in a lab-scale wastewater treatment

    OpenAIRE

    Jaime L. M. Oliveira; Langenbach, Tomaz; Dezotti, Márcia

    2008-01-01

    The fate of organochlorine 14C-dicofol in activated sludge process was investigated. Results showed that the major part of radioactivity remained adsorbed on biological sludge. Consequently, its final disposal deserves special attention. The small amounts of dicofol, biotransformed or not, which remained in the treated effluent could contaminate receiving bodies.

  18. Semiempirical model for diagnostication Helicobacter pylori infection by use of 14C labelled urea

    International Nuclear Information System (INIS)

    The main aim of this study was to create a semiempirical model, helpful in estimating severity of the Helicobacter pylori (H.pylori) infection by using the urea breath test (UBT), when urea labelled 14C has been used for diagnostics. The model consists of four compartments representing stomach (1), blood vascular system (2), lungs (3) and urinary system (4). Mathematical model is based on the balance of radioactive 14C in compartments from 1 to 4. The histological investigations were used as reference methods. Comparison of the results obtained from simulation, which yields dependence of 14C activity on time, to experimental results of UBT, made it possible to determine the ranges of coefficient HB value, which characterized each degrees of severity of H. pylori infection: degree 0 (lack of infection) - hB below 0.025; degree 1 (not large) - hB in range 0.025-0.115; degree 2 (moderate) - hB in the range 0.115-0.300; degree 3 (significant) - hB above 0.300. It was possible to estimate severity of H.pylori infection in clinical practice on the basis of comparing the 14C activity value of experimental points as obtained from the breath test, to the results of simulation with suitable value of the fitted parameter hB indicating degree of severity of infection. (author)

  19. Kernel abortion in maize. II. Distribution of 14C among kernel carboydrates

    International Nuclear Information System (INIS)

    This study was designed to compare the uptake and distribution of 14C among fructose, glucose, sucrose, and starch in the cob, pedicel, and endosperm tissues of maize (Zea mays L.) kernels induced to abort by high temperature with those that develop normally. Kernels cultured in vitro at 309 and 350C were transferred to [14C]sucrose media 10 days after pollination. Kernels cultured at 350C aborted prior to the onset of linear dry matter accumulation. Significant uptake into the cob, pedicel, and endosperm of radioactivity associated with the soluble and starch fractions of the tissues was detected after 24 hours in culture on atlageled media. After 8 days in culture on [14C]sucrose media, 48 and 40% of the radioactivity associated with the cob carbohydrates was found in the reducing sugars at 30 and 350C, respectively. Of the total carbohydrates, a higher percentage of label was associated with sucrose and lower percentage with fructose and glucose in pedicel tissue of kernels cultured at 350C compared to kernels cultured at 300C. These results indicate that sucrose was not cleaved to fructose and glucose as rapidly during the unloading process in the pedicel of kernels induced to abort by high temperature. Kernels cultured at 350C had a much lower proportion of label associated with endosperm starch (29%) than did kernels cultured at 300C (89%). Kernels cultured at 350C had a correspondingly higher proportion of 14C in endosperm fructose, glucose, and sucrose

  20. Adsorption-desorption, mobility and degradation of 14C-Glyphosate in two soil series

    International Nuclear Information System (INIS)

    The adsorption desorption and degradation of glyphosate (Roundup) have been studied using 14C glyphosate in two soils, namely Serdang Series and Sungai Buloh Series. The percentage of adsorption was not significantly different (p14C- glyphosate was detected in 0-10 cm zone of the two soils studied. However, in Sungai Buloh Series, a significant amount of 14C-glyphosate was detected in the 10-20 cm zone. A small amount of 14C radioactivity was also detected in the leachate of the two soils. The percentage of degradation in the Sungai Buloh and Serdang Series soils was higher at 10 μg/ml and 50 μg/ml, concentration, respectively. At 50 μg/ml concentration the Sungai Buloh Series soil showed higher glyphosate residue (83%) as compared to Serdang Series (48%). In contrast, the glyphosate residue was found to be higher in the Serdang Series (73916) as compared to the Sungai Buloh Series (30%) at 10 μg/ml concentration. (Author)

  1. 3$\\alpha$-cluster structure and monopole transition in $^{12}$C and $^{14}$C

    CERN Document Server

    Yoshida, Yuta

    2016-01-01

    3$\\alpha$-cluster structures and monopole transitions of $0^+$ states in $^{12}$C and $^{14}$C were investigated with $3\\alpha$- and $^{10}$Be+$\\alpha$-cluster models. A gas-like $3\\alpha$ state and a bending-chain $3\\alpha$ state were obtained in the $0^+_2$ and $0^+_3$ states of $^{12}$C, respectively. In $^{14}$C, a linear-chain 3$\\alpha$ structure is found in the $0^+_4$ state near the $^{10}$Be+$\\alpha$ threshold, but a cluster gas-like state does not appear because valence neutrons attract $\\alpha$ clusters and suppress spatial development of 3$\\alpha$ clustering. It was found that the linear-chain state in $^{14}$C is stabilized against the bending and $\\alpha$ escaping modes by valence neutrons. The monopole transition strengths in $^{12}$C are enhanced by $3\\alpha$-cluster developing, whereas, those in $^{14}$C are not enhanced so much because of the tight binding of $\\alpha$ clusters by valence neutrons.

  2. Enzymatic aryl-O-methyl-14C labeling of model lignin monomers

    International Nuclear Information System (INIS)

    Aryl-O-methyl ethers are abundant in aerobic and anaerobic environments. In particular, lignin is composed of units of this type. Lignin monomers specifically radiolabeled in methoxy, side chain, and ring carbons have been synthesized by chemical procedures and are important in studies of lignin synthesis and degradation, humus formation, and microbial O-demethylation. In this paper attention is drawn to an enzymatic procedure for preparing O-methyl-14C-labeled aromatic lignin monomers which has not previously been exploited in microbial ecology and physiology studies and which has several advantages compared with chemical synthesis procedures. O-[methyl-14C]vanillic and O-[methyl-14C]ferulic acids were prepared with S-[methyl-14C]adenosyl-L-methionine as the methyl donor, using commercially obtained porcine liver catechol-O-methyltransferase (EC 2.1.1.6). The specific activity of the methylated products was the same as that of the methyl donor, a maximum of about 58 μCi/μmol, and the yields were 42% (vanillate) and 35% (ferulate). Thus lignin monomers are readily prepared as O-methylated products of the catechol-O-methyltransferase reaction and, with this enzyme method of preparation, would be more widely available than labeled compounds which require chemical synthesis

  3. Nuclear Structure Effects in the Exotic Decay of $^{225}$Ac via $^{14}$C Emission

    CERN Multimedia

    2002-01-01

    % IS323 \\\\ \\\\ We propose to build at Isolde a high intensity $^{225}$Ac source by $\\beta$-decay of $^{225}$(Ra+Fr) beam, to be used at the superconducting spectrometer SOLENO of IPN-Orsay in order to study a possible fine structure in the spectrum of $^{14}$C ions spontaneously emitted by $^{225}$Ac.

  4. The impact of new 14C dating on the European Neanderthal versus modern human discussion

    International Nuclear Information System (INIS)

    Full text: One of the most interesting time periods in human evolution is the transition period from Neanderthals to modern humans. The fate of the Neanderthals and the mode of the emergence of modern humans in Europe is still unresolved. It was speculated by some investigators that the Neanderthals could have been pushed to the margins of the continent by the early modern humans. Others argue that Neanderthals and modern humans may have co-existed over a considerable long time period in the same regions and even may have mixed with each other. Direct 14C dating of the rare and valuable human remains with accelerator mass spectrometry in combination with anthropological investigations and DNA-analysis offers a tool to shed light on this debate. The VERA laboratory contributed to this question by the successful direct 14C dating of the Mladec fossils - remains of early upper palaeolithic men - found in Moravia (Czech Republic) at the end of the 19th century and stored since then in the Museum of Natural History in Vienna. The determined 14C age of ∼ 31 ka BP (non-calibrated) indicates that the Mladec finds comprise one of the oldest substantial assemblage of human remains in Central Europe and play an important role in the Neanderthal / modern human discussion. It should be noted that the 14C age could correspond to an absolute age of several thousand years older. Unfortunately a reliable calibration of this age range is currently not possible. (author)

  5. Fine structures in 14C emission of 223Ra and 224Ra

    International Nuclear Information System (INIS)

    The measurement of the energy spectrum of 14C nuclei emitted in the spontaneous radioactivity from 223Ra and 224Ra has been carried out, using thin and intense sources (480 MBq for 223Ra and 3550 MBq for 224Ra). The sources were obtained by implanting mass-separated beams from ISOLDE (CERN) into Al and vitreous C catchers. The measurement was performed with the supraconducting solenoidal spectrometer SOLENO installed at Orsay. The discovery, of a fine structure in the energy spectrum of 14C emission from 223Ra, which is analogous to the one known for α emission, is confirmed. Only 13% of the branching ratio in 14C decay leads to the ground state of the residual nucleus, while 8l% to the first excited state. For 14C emission of 224Ra, a lower limit of 2 for the hindrance factor has been measured for the transition to the first excited state in the residual nucleus. Also, a precise identification in Z with a E·ΔE telescope has been performed for the radiation from the 223Ra source. (author) 22 refs., 11 figs., 1 tab

  6. Planktonic primary production evaluation by means of the 14C method with liquid scintillation counting

    International Nuclear Information System (INIS)

    Preliminary results on the planktonic primary production obtained for the first time with the 14C method off the Romanian Black Sea coast (1977, 1978) and in the Sinoe, Mamaia and Bicaz lakes (1978) are presented, along with a review of this method with special reference to liquid scintillation counting. 140 Refs. (author)

  7. Fate of 14C-Ethyl Profenofos in Tomato Fruits And Tomato Products

    International Nuclear Information System (INIS)

    14C--Ethyl profenofos and some of its degradation products have been prepared for the present investigation. The fate of 14C-residues of profenofos in tomato fruits collected at different time intervals from plants treated with 14C-insecticide under conditions of local practice was determined. The results indicated that the profenofos residues in fruits increases with time during the first week, and amount of decreases rapidly during the second week. Some processing methods of tomato fruits affected a decrease in the level of 14C-profenofos residue. It was greatly reduced in juice (74.7%). Obvious reduction in the level of insecticide residues was detected in both puree and paste (78.2% and 89.9%, respectively). Analysis of radioactive extracts showed that the degradation products in juice, puree and paste were similar to those found in the fruit. The degradation compounds detected were O-(2-chlorophenyl)-S-propyl-phosphorothioate, O-ethyl-S-propyl phosphoric acid and O-ethyl phosphoric acid, in addition to one unknown. The phenolic compounds were found in free and conjugated forms

  8. Mass Balance Model, A study of contamination effects in AMS 14C sample analysis

    NARCIS (Netherlands)

    Prokopiou, Markella

    2010-01-01

    In this training thesis a background correction analysis, also known as mass balance model, was implemented to study the contamination effects in AMS 14C sample processing. A variety of backgrounds and standards with sizes ranging from 50 μg C to 1500 μg

  9. Nitrogen mustard derivated from adiphenine. Synthesis and 14C labelling. Antitumor activity and tissular distribution

    International Nuclear Information System (INIS)

    The synthesis of a new nitrogen mustard 14C is described. The compound is found to be active in intraperitoneal murine L 1210 and P 388 tumors. Preliminary tissue distribution studies after i.v. administration to rats and mice show that the mustard and/or its metabolites partially cross the blood-brain barrier

  10. 14C dating of bone using (gamma) Carboxyglutamic Acid and Carboxyglycine (Aminomalonate)

    Energy Technology Data Exchange (ETDEWEB)

    Southon, J R; Burky, R T; Kirner, D L; Taylor, R E; Hare, P E

    1999-04-27

    Radiocarbon determinations have been obtained on {gamma}-carboxyglutamic acid [Gla] and {alpha}-carboxyglycine (aminomalonate) [Am] as well as acid- and base-hydrolyzed total amino acids isolated from a series of fossil bones. As far as they are aware, Am has not been reported previously in fossil bone and neither Gla nor Am {sup 14}C values have been measured previously. Interest in Gla, an amino acid found in the non-collagen proteins osteocalcin and matrix Gla-protein (MGP), proceeds from the suggestion that it may be preferentially retained and more resistant to diagenetic contamination affecting {sup 14}C values in bones exhibiting low and trace amounts of collagen. The data do not support these suggestions. The suite of bones examined showed a general tendency for total amino acid and Gla concentrations to decrease in concert. Even for bones retaining significant amounts of collagen, Gla (and Am extracts) can yield {sup 14}C values discordant with their expected age and with {sup 14}C values obtained on total amino-acid fractions isolated from the same bone sample.

  11. From 14C/12C measurements towards radiocarbon dating of ice

    International Nuclear Information System (INIS)

    A dry extraction method of CO2 included in glacier ice adds a contamination equivalent to 1.8 μg modern carbon for a 35 μg C sample. This enables radiocarbon dating by accelerator mass spectrometry of 35 μg C samples to about 25 000 BP. Measured 14C/12C ratios are presented for a part of the Vostok ice core, and for some surface samples; high 14C/12C values ranging between 65 and 105 pm C indicate in-situ 14C production during the ablation. The reproducibility of radiocarbon dating of ice is demonstrated by results for some parts of the Caroline core, yielding an age versus depth profile, in which the age does not simply increases with depth. The results indicate that the accuracy of radiocarbon dating of ice is not limited by the statistical error arising in the accelerator measurements, but by the uncertainty in the contamination background of the samples and by the in-situ production of 14C. 12 refs, 4 figs, 2 tabs

  12. Characterization of {sup 14}C in neutron irradiated NBG-25 nuclear graphite

    Energy Technology Data Exchange (ETDEWEB)

    LaBrier, Daniel, E-mail: labrdani@isu.edu; Dunzik-Gougar, Mary Lou

    2014-05-01

    Recent studies suggest that the highest concentration of {sup 14}C contamination present in reactor-irradiated graphite exists on the surfaces and within near-surface layers. Surface-sensitive analysis techniques (XPS, ToF-SIMS, SEM/EDS and Raman) were employed to determine the chemical nature of {sup 14}C on irradiated NBG-25 (nuclear grade) graphite surfaces. Several {sup 14}C precursor species are identified on the surfaces of irradiated NBG-25; the quantities of these species decrease at sub-surface depths, which further suggests that {sup 14}C formation is predominantly a surface-concentrated phenomenon. The elevated presence of several surface oxide complexes on irradiated NBG-25 surfaces are attributed directly to neutron irradiation. Larger numbers of oxide bonds were found on irradiated NBG-25 surfaces (when compared to unirradiated samples) in the form of interlattice (e.g. ether) and dangling (e.g. carboxylate and ketone) bonds; the quantities of these bond types also decrease with increasing sub-surface depths.

  13. Use of an external source (60Co) for 32P detection efficiency determination by the Cerenkov effect, in soil extracts

    International Nuclear Information System (INIS)

    The detection of 32P in aqueous extracts is usually made with the aid of a Geiger-Muller detector, with thin window and sample on a planchet. Presently the technique is being developed of detection of high energy beta particles emitters (32P, 42K, 86Rb) through the Cerenkov effect, using a commercial liquid scintillation system. This technique, despite being approximately 30 times more sensitive, has the inconvenience of varying the detection efficiency, mainly for color samples (soil extracts, for instance). From this stems the need for determining the detection efficiency for each sample. The internal standardization and channels ratio methods show a series of drawbacks, mainly the non-reutilization of the samples (1st method) and statistical uncertainty for low activity samples (2nd method). The elimination of these dreawbacks can be achieved through the utilization of the external standardization method. A 60Co source with 1,4 μCi activity has been adapted to the sample elevator of the detector system, and a comparison was made with the channels ratio method to evaluate the efficiency of 32P detection in soil extracts (P extraction and fractionation). The external standardization method showed to be more accurate, besides being influenced to a lesser degree by high voltage variation, sample volume and vial types. In the case of large samples, it is advisable to carry out detection in vials filled up to their full capacity; in the case of small samples, the whole volume should be transferred to the vials and completed up to 9 ml for nylon vials,10 ml for glass vials and 11 to 14 ml for polyethilene vials. On the other hand, plastic vials showed higher detection efficiency than ones. As to background radiation, the lowest rates were given by nylon vials and the highest by Beckman glass vials

  14. Studies on uptake and translocation of sulphur in oil seed rape plant using 35S tracer technique

    International Nuclear Information System (INIS)

    The experiments were conducted to investigate the uptake and translocation of 35S in oil seed rape at different stages. The results showed that uptake of sulphur from soil by rape plant were 23.59%, 31.65% and 49.13% of sulphur applied at transplanting, bolting and flowering stage, respectively. About 40% of 35S taken from soil was located in seeds for transplanting and flowering stage applying. About 20% of sulphur applied on top four leaves at various stages of growth was remained in labelled leaves and 21%∼23% was transported to pods with majority in branch pods. 40%∼60% of sulphur which was applied on surface of pods at lower stem at different time after flowering was remained in shell of labelled pods and 13%∼16.8% of that was transferred into seeds of labelled pods. Recoveries of labelled sulphur applied on pods from seeds of pods at branches were less than 10%. The transportation of 35S from labelled sites to seeds of labelled pods and unlabelled pods was declined sharply as labelling was carried out at 6 weeks after flowering

  15. Using 14C to investigate Methane Production and DOC Reactivity in Northern Peatlands

    Science.gov (United States)

    Corbett, J.; Chanton, J.; Glaser, P.; Burdige, D.; Siegel, D.; Cooper, W.

    2008-12-01

    We found a consistent distribution pattern for radiocarbon in dissolved organic carbon (DOC), dissolved inorganic carbon (DIC), and methane replicated across spatial and temporal scales in northern peatlands from Minnesota to Alaska. The 14C content of DOC is relatively modern throughout the peat column, to depths of 3 meters. In sedge-dominated peatlands, the 14C content of the products of respiration, CH4 and DIC are essentially the same, and are similar to that of DOC. In Sphagnum-woody plant dominated peatlands with few sedges, however, the respiration products are similar but intermediate between the 14C content of the solid-phase peat and the DOC. Preliminary data indicates qualitative differences in the pore-water DOC depending on the extent of sedge cover, consistent with the hypothesis that the DOC in sedge-dominated peatlands is more reactive than DOC in peatlands where Sphagnum or other vascular plants dominate. These data are supported by molecular-level analysis of DOC by ultrahigh resolution mass spectrometry which suggests dramatic changes with depth in the composition of DOC in the sedge-dominated peatland porewaters but not in porewaters where Sphagnum dominates. The higher reactivity of DOC from sedge- dominated peatlands may be a function of either different source materials or environmental factors that are related to the abundance of sedges in peatlands. To further investigate the reactivity of peat DOC in anaerobic methane producing environments, we are conducting size fractionation experiments for both the bog and fen samples. We will analyze resulting size fractions of DOC for radiocarbon. Previous research has shown that microorganisms tend to prefer HMW DOC to LMW DOC. Due to this, we believe that LMW DOC from both the bogs and the fens will result in radiocarbon values that are more depleted in 14C relative to HMW DOC. We hypothesize that the HMW DOC from the bogs will show depletion in 14C relative to HMW DOC in the fens. We further

  16. 14C AMS measurements of tree leaf samples to monitor air pollution induced by city traffic

    International Nuclear Information System (INIS)

    In the past, many radiocarbon measurement have been made for environmental studies such as source apportionment of air-borne particulates, and studies of the anthropogenic effects of nuclear power plants. In this presentation we report our accelerator mass spectrometry (AMS) measurements of radiocarbon on tree leaf samples to investigate the impact of city traffic on our living-environment. The fossil-burning vehicles emit carbon dioxide (CO2) free of 14C content and, when mixed with the clean air CO2, lower 14C ratio compared to the normal reservoir value. This so-called Suess effect can be incorporated to monitor air quality in our living environments, since metabolic processes maintain the 14C content of living organism in equilibrium with atmospheric 14C. In other words, dead CO2 is admixed to the normal atmospheric CO2 and then photo-synthetically assimilated by the plants. Two kinds of tree leaf samples; pine tree needles and Ginkgo tree leaves were collected during a one-week period in the summer 1996 at five different locations with various traffic conditions in the region, within a 10-km diameter circle, south of the River Han, Seoul. The AMS targets were made by a simple sample-making procedure. The leaves have been pretreated by a standard acid-alkali treatment and then charred in a vacuum evaporator by applying ca. 800 deg C heat. The charred samples were mixed with Ag powder and pressed into the Al target holder for the AMS measurement.The AMS measurements were made using the accelerator mass spectrometry facilities of the Leibniz-Labor at the Christian-Albrecht University, Kiel,Germany. The observed Δ14C values, which ranged from 60TM to 158TM, have a good correlation with the traffic conditions in the places where the sampling took place and show a remarkable capability of 14C AMS measurements to monitor our fossil burning environment. The volume ratios of clean air to air from fossil-burn origin in the environmental CO2 reached to a level of 8

  17. 14C accelerator mass spectrometry - applications in archaeology, biomedicine and in the atmospheric sciences

    International Nuclear Information System (INIS)

    Accelerator mass spectrometry (AMS) is superior to all other analytical techniques in its detection sensitivity of radiocarbon (14C). It has therefore influenced or even laid down the foundations for applications in many fields of science. In the current work, various applications of 14C AMS are presented through published articles for which the measurements were performed at the Vienna Environmental Research Accelerator (VERA). These articles are embedded into an in-depth discussion about characteristic features of the respective fields, emphasizing the broad range of issues which need to be considered in interdisciplinary research. In archaeology new 14C dates on equipment of the Iceman ('Oetzi'), the world's oldest intact mummy, show reasonable agreement with dates previously obtained on the Iceman himself (3360-3100 BC). However, several botanical remains from the finding place clearly belong to other time periods, indicating that the discovery site of Oetzi has been used as a mountain pass 1500 yr earlier and also 2000 yr later. Dating on spruce logs from the world's oldest salt mines at Hallstatt, Austria provide evidence that salt mining started 1-2 centuries earlier than previously supposed, i.e. in the 14th to the 13th century BC. Recently, Bayesian mathematics is a frequently used tool in calibrating radiocarbon data. So-called vague or non-informative priors employed in this method may cause severe problems as shown by extensive computer simulations. In biomedicine problems in toxicology and in forensic medicine were investigated. Heterocyclic amines (HAs) are probably the epidemiologically most relevant class of mutagenic and carcinogenic substances since they are produced naturally in cooking protein-rich food. A study of 14C labeled HAs (MeIQx and PhIP) in rodents and humans, one of the first studies using 14C-labeled mutagens also in healthy human volunteers, severely calls in question the validity of animal models for assessing heterocyclic amine

  18. Phyto remediation of 14C-fenvalerate insecticide contamination by fresh water weed potamogeton sp

    International Nuclear Information System (INIS)

    The present experiment was carried out to throw some light on the possibility of the fresh water-weed Potamogeton sp for the phyto remediation of 14C-fenvalerate residues. In addition, the effect of the insecticide on some physiological parameters was also investigated. At the beginning of the experiment(zero time),14C-fenvalerate from a previous experiment carried out earlier in an aquarium in the laboratory. The potamogeton plants (125 g) having newly grown roots were transplanted in the aquarium. The amount of 14C-activity in water was remarkably decreased from 6.54μg/ml at zero time to 1.84μg/ml at the end of the experiment (384 h). In the soil, a slight decrease in 14C-activity was recorded from 15.23μg/g at zero time to 13.7μg/g at the end of the experiment. On the other hand,14C-activity in the plant was increased during the mentioned period by about 19.1%. Control and treated samples showed an increase in both chlorophyll a and b up to 96 h then their values were decreased thereafter. The carotenoid fractions in the tested plants were increased gradually up to 96 h then decreased relative to the control samples. Soluble sugars in treated plants showed maximum increase at 48 h (129.8%) then decreased to 114.3% at 192 h and to 104.7% at 384 h but still had higher values than those at zero time. A slight and gradual increase in the protein content of the treated Potamogeton plants was occurred at the first 24 h, then started to decrease than the values of corresponding controls starting from 48 h to 384 h

  19. Distribution and fate of 14C-acephate in tomato plants and soil

    International Nuclear Information System (INIS)

    This experiment was carried out using tomato plants (3-8 weeks old) that were planted in soil inside a PVC tube (inner diameter, 8.5 cm; height, 20 cm). Ten millilitres of 14C-acephate (O,S-dimethyl acetyl phosphoramidothioate) solution (0.0214 μCi/mL, 26.5 ppm) were applied to the soil. At the vegetative phase, the 14C-acephate residues were higher in the older leaves than in the younger leaves. At the generative phase, 0.06% 14C-acephate was detected in fruits on day 1, 0.9% on day 4, 1.5% on day 7 and 3% on day 14. The 14C-acephate residues and their metabolites in soil were determined using this layer chromatography (TLC) and gas-liquid chromatography (GLC) on a packed column of 3% CHDMS on Chromosorb WAW. The 14C-acephate results from TLC and GLC, respectively, were 51.2 and 59.1% on day 1, 24.1 and 24.5% on day 4, 11.8 and 17.1% on day 7 and 3.1 and 3.1% on day 14. The metabolite, methamidophos, showed 2.5% on day 1, 9.2% on day 4, 11.3% on day 7 and 2.2% on day 14, obtained by TLC. TLC analysis showed that the acephate and methamidophos, respectively, in leaves were 3.9 and 0.8% on day 1, 4.5 and 1.5% on day 4, 7.1 and 7.5% on day 7, and 5.5 and 10.3% on day 14. (author). 5 refs, 1 fig., 3 tabs

  20. Mineralization and Transfer Processes of {sup 14}C-labeled Pesticides in Outdoor Lysimeters

    Energy Technology Data Exchange (ETDEWEB)

    Grundmann, Sabine; Doerfler, Ulrike, E-mail: doerfler@gsf.de; Ruth, Bernhard; Loos, Christine [GSF - National Research Center for Environment and Health, Institute of Soil Ecology (Germany); Wagner, Tobias [GSF - National Research Center for Environment and Health, Institute of Biochemical Plant Pathology (Germany); Karl, Heidrun; Munch, Jean Charles; Schroll, Reiner [GSF - National Research Center for Environment and Health, Institute of Soil Ecology (Germany)

    2008-04-15

    A recently designed two-chamber-lysimeter-test-system allows the detailed investigation of degradation, transport and transfer processes of {sup 14}C-labeled substances in soil-plant-atmosphere-systems under outdoor conditions. With this test system it is feasible to distinguish between {sup 14}C-emissions from soil surfaces and {sup 14}C-emissions from plant surfaces in soil monoliths under real environmental conditions. Special soil humidity sensors allow the measurement of soil water content near to the soil surface, in 1 and 5 cm depth. The behavior of organic chemicals can be followed for a whole vegetation period and a mass balance for the applied chemical can be established. Some selected results of the herbicides isoproturon and glyphosate - using the two-chamber-lysimeter-test-system - are presented to demonstrate its applicability for the identification and quantification of the processes that govern pesticide behavior in soil-plant-systems. Mineralization of {sup 14}C-isoproturon was very different in four different soils; the mineralization capacity of the soils ranged from 2 to 60%. Leaching of isoproturon in general was very low, but depending on the soil type and environmental conditions isoproturon and its metabolites could be leached via preferential flow, especially shortly after application. For the herbicide {sup 14}C-glyphosate no accumulation of residues in the soil and no leaching of the residues to deeper soil layers could be observed after three applications. Glyphosate was rapidly degraded to AMPA in the soil. Glyphosate and AMPA were accumulated in soy bean nodules.

  1. Characteristics of 14C and 13C of carbonate aerosols in dust storm events in China

    Science.gov (United States)

    Chen, Bing; Jie, Dongmei; Shi, Meinan; Gao, Pan; Shen, Zhenxing; Uchida, Masao; Zhou, Liping; Liu, Kexin; Hu, Ke; Kitagawa, Hiroyuki

    2015-10-01

    In contrast with its decrease in western China deserts, the dust storm event in eastern China, Korea, and Japan shows an increase in frequency. Although the drylands in northeastern China have been recognized as an important dust source, the relative contributions of dust transport from the drylands and deserts are inconclusive, thus the quantification of dust storm sources in downwind area remains a challenge. We measured the 14C and 13C contents in carbonates of dust samples from six sites in China, which were collected for the duration of dust storm events in drylands, deserts, and urban areas. The δ13C of the dryland dust samples considerably varied in a range of - 9.7 to - 5.0‰, which partly overlapped the desert dust carbonate δ13C ranges. The 14C content of the dryland dust carbonates showed a narrow range of 60.9 ± 4.0 (as an average and 1 SD of five samples) percent modern carbon (pMC), indicating the enrichment of modern carbonate. Dust samples in desert regions contained relatively aged carbonates with the depleting 14C showing of 28.8 ± 3.3 pMC. After the long-range transport of the western China desert dust plume, the carbonates collected at the southern China remained the depletion of 14C (33.5 ± 5.3 pMC) as in the desert regions. On the other hand, the samples of dust storm events at the urban areas of eastern China showed an enrichment of 14C contents (46.2 ± 5.0 pMC, n = 7), which might be explained by the stronger contribution of modern-carbonate-rich dryland dust.

  2. Reconciling Change in Oi-Horizon 14C With Mass Loss for an Oak Forest

    Energy Technology Data Exchange (ETDEWEB)

    Hanson, P J; Swanston, C W; Garten, Jr., C T; Todd, D E; Trumbore, S E

    2005-06-27

    First-year litter decomposition was estimated for an upland-oak forest ecosystem using enrichment or dilution of the {sup 14}C-signature of the Oi-horizon. These isotopically-based mass-loss estimates were contrasted with measured mass-loss rates from past litterbag studies. Mass-loss derived from changes in the {sup 14}C-signature of the Oi-horizon suggested mean mass loss over 9 months of 45% which was higher than the corresponding 9-month rate extrapolated from litterbag studies ({approx}35%). Greater mass loss was expected from the isotopic approach because litterbags are known to limit mass loss processes driven by soil macrofauna (e.g., fragmentation and comminution). Although the {sup 14}C-isotope approach offers the advantage of being a non-invasive method, it exhibited high variability that undermined its utility as an alternative to routine litterbag mass loss methods. However, the {sup 14}C approach measures the residence time of C in the leaf litter, rather than the time it takes for leaves to disappear; hence radiocarbon measures are subject to C immobilization and recycling in the microbial pool, and do not necessarily reflect results from litterbag mass loss. The commonly applied two-compartment isotopic mixing model was appropriate for estimating decomposition from isotopic enrichment of near-background soils, but it produced divergent results for isotopic dilution of a multi-layered system with litter cohorts having independent {sup 14}C-signatures. This discrepancy suggests that cohort-based models are needed to adequately capture the complex processes involved in carbon transport associated with litter mass-loss. Such models will be crucial for predicting intra- and interannual differences in organic horizon decomposition driven by scenarios of climatic change.

  3. Whole-body distribution of {sup 14}C-labeled silica nanoparticles and submicron particles after intravenous injection into Mice

    Energy Technology Data Exchange (ETDEWEB)

    Sakai, Nobumitsu, E-mail: sakai@risk.env.kyoto-u.ac.jp; Takakura, Masato; Imamura, Harutoshi [Kyoto University, Division of Environmental Engineering, Graduate School of Engineering (Japan); Sugimoto, Miki [Kyoto University, Division of Applied Biosciences, Graduate School of Agriculture (Japan); Matsui, Yasuto [Kyoto University, Division of Environmental Engineering, Graduate School of Engineering (Japan); Miyoshi, Hirokazu [University of Tokushima, Radioisotope Research Center (Japan); Nakayama, Aki; Yoneda, Minoru [Kyoto University, Division of Environmental Engineering, Graduate School of Engineering (Japan)

    2012-05-15

    We analyzed the whole-body distribution of {sup 14}C-ADP-labeled silica nanoparticles ({sup 14}C-ADP-SiO{sub 2} nanoparticles) and submicron particles ({sup 14}C-ADP-SiO{sub 2} submicron particles) after intravenous injection into ICR mice. The {sup 14}C-ADP-SiO{sub 2} nanoparticles and submicron particles were synthesized before the injection and the particle size was 19.6 and 130 nm, respectively. Similarly, the shape was spherical and the crystallinity was amorphous. After the synthesis, we injected mice with the {sup 14}C-ADP-SiO{sub 2} nanoparticles or the {sup 14}C-ADP-SiO{sub 2} submicron particles and dissected tissues after 1, 2, 4, 8 and 24 h. The radioactivity in the tissues was measured with a liquid scintillation counter. As a result, the retention percentage in bone, skin, lymph nodes, and the digestive mixture was at least twofold higher in the {sup 14}C-ADP-SiO{sub 2} nanoparticles-exposed mice, whereas the retention percentage in the kidney was statistically higher in the {sup 14}C-ADP-SiO{sub 2} submicron particles-exposed mice. Both types of {sup 14}C-ADP-SiO{sub 2} particles mainly translocated to the muscle, bone, skin, and liver, but hardly translocated to the brain and olfactory bulb. Furthermore, the {sup 14}C-ADP-SiO{sub 2} nanoparticles had a higher retention percentage (62.4 %) in the entire body at 24-h post-injection than did the {sup 14}C-ADP-SiO{sub 2} submicron particles (50.7 %). Therefore, we suggested that the {sup 14}C-ADP-SiO{sub 2} nanoparticles might be more likely than the {sup 14}C-ADP-SiO{sub 2} submicron particles to be retained in the body, and consequently they might be gradually accumulated by chronic exposure.

  4. Development of a flow-sheet for the radiochemical processing of irradiated sulphate targets for the production of carrier-free 32P

    International Nuclear Information System (INIS)

    Carrier-free 32P was produced in KAlpakkam MINI reactor (KAMINI) via 32S (n, p) 32P using its small fast flux component. This method has established the flow-sheet for the production of 32P from sulphate targets such as magnesium sulphate and strontium sulphate which can withstand high temperatures of fast reactors unlike the conventionally used sulphur powder. The chemical processing involved (i) struvite precipitation method for magnesium sulphate and (ii) co-precipitation with ferric hydroxide method for strontium sulphate. (author)

  5. Increased root exudation of 14C-compounds by sorghum seedlings inoculated with nitrogen-fixing bacteria

    International Nuclear Information System (INIS)

    Organic components leaked from Sorghum bicolor seedlings ('root exudates') were examined by recovering 14C labelled compounds from root solutions of seedlings inoculated with Azospirillum brasilense, Azotobacter vinelandii or Klebsiella pneumoniae nif-. Up to 3.5% of the total 14C recovered from shoots, roots, and nutrient solutions was found in the root solutions. Inoculation with Azospirillum and Azotobacter increased the amounts of 14C and decreased the amounts of carbohydrates in the root solutions. When sucrose was added as a carbon source for the bacteria, the increase of 14C in the solutions did not occur. Quantities of 14C found in the root solutions were proportional to amounts of mineral nitrogen supplied to the plants. Bacterial growth also was proportional to nitrogen levels. When sorghum plants were grown in soil and labelled with 14CO2, about 15% of the total 14C recovered within 48 hours exposure was found in soil leachates. (orig.)

  6. Tissue uptake, distribution and elimination of {sup 14}C-PFOA in zebrafish (Danio rerio)

    Energy Technology Data Exchange (ETDEWEB)

    Ulhaq, Mazhar [Department of Biomedical Sciences and Veterinary Public Health, Swedish University of Agricultural Sciences, SE-750 07 Uppsala (Sweden); Sundström, Maria [Environmental Chemistry Unit, Department of Materials and Environmental Chemistry, Stockholm University, SE-106 91 Stockholm (Sweden); Larsson, Pia; Gabrielsson, Johan [Department of Biomedical Sciences and Veterinary Public Health, Swedish University of Agricultural Sciences, SE-750 07 Uppsala (Sweden); Bergman, Åke [Environmental Chemistry Unit, Department of Materials and Environmental Chemistry, Stockholm University, SE-106 91 Stockholm (Sweden); Norrgren, Leif [Department of Biomedical Sciences and Veterinary Public Health, Swedish University of Agricultural Sciences, SE-750 07 Uppsala (Sweden); Örn, Stefan, E-mail: Stefan.Orn@slu.se [Department of Biomedical Sciences and Veterinary Public Health, Swedish University of Agricultural Sciences, SE-750 07 Uppsala (Sweden)

    2015-06-15

    Highlights: • Bioconcentration of PFOA at steady-state was approximately 20–30 times. • High concentrations were observed in bile and intestines implying enterohepatic circulation. • PFOA accumulated in oocytes indicating maternal transfer. - Abstract: Perfluorooctanoic acid (PFOA) is a long-chain perfluorinated chemical that has been shown to be non-degradable and persistent in the environment. Laboratory studies on bioconcentration and compound-specific tissue distribution in fish can be valuable for prediction of the persistence and environmental effects of the chemicals. In the present study male and female zebrafish (Danio rerio) were continuously exposed to 10 μg/L of radiolabeled perfluorooctanoic acid ({sup 14}C-PFOA) for 40 days, after which the exposed fish were transferred to fresh clean water for another 80 days wash-out period. At defined periodic intervals during the uptake and wash-out, fish were sampled for liquid scintillation counting and whole body autoradiography to profile the bioconcentration and tissue distribution of PFOA. The steady-state concentration of {sup 14}C-PFOA in the zebrafish was reached within 20–30 days of exposure. The concentration-time course of {sup 14}C-PFOA displayed a bi-exponential decline during washout, with a terminal half-life of approximately 13–14 days. At steady-state the bioconcentration of {sup 14}C-PFOA into whole-body fish was approximately 20–30 times greater than that of the exposure concentration, with no differences between females and males. The bioconcentration factors for liver and intestine were approximately 100-fold of the exposure medium, while in brain, ovary and gall bladder the accumulation factors were in the range 15–20. Whole-body autoradiograms confirmed the highest labeling of PFOA in bile and intestines, which implies enterohepatic circulation of PFOA. The {sup 14}C-PFOA was also observed in maturing vitellogenic oocytes, suggesting chemical accumulation via yolk proteins

  7. Seasonal variations of 14C and δ13C for cave drip waters in Ryugashi Cave, Shizuoka Prefecture, central Japan

    Science.gov (United States)

    Minami, Masayo; Kato, Tomomi; Horikawa, Keiji; Nakamura, Toshio

    2015-11-01

    Speleothem 14C has recently emerged as a potentially powerful proxy for hydrology changes in comparison with atmospheric 14C calibration curve, rather than as a direct dating tool, apart from a time marker using bomb peak of 14C. Some possible causes for the relationship between speleothem 14C content (or dead carbon fraction: DCF) and karst hydrology have been proposed, such as changes in temperature, precipitation, drip water flow dynamics, cave air ventilation, soil air pCO2. In this study, we investigated seasonal variation in 14C and δ13C of drip water in Ryugashi Cave, Shizuoka Prefecture, central Japan, to examine the causes of the 14C and δ13C variations in a speleothem. The results show that different 14C concentrations and δ13C values of drip water from the Ryugashi Cave, were exhibited at different sites of the Caves No. 1, No. 3, and No. 4, which have different temperature, air pCO2, and flow paths. Further, the 14C and δ13C of drip waters showed seasonal variations at all sites, which were lower in fall and winter, and higher in spring and summer, though the extent of the variations was different among the sites. The 14C in drip waters tended to be correlated with the drip rates: 14C tended to be higher in drip waters with higher drip rates, and also correlated with rainfall amount around the Ryugashi Cave, especially for the drip waters in Cave No. 3, which are considered to have simpler flow paths. The increase in rainfall amount could bring the increase in drip rate of drip water, and then the decrease in interaction between solution and karst, resulting in 14C increase (DCF decrease) in drip water. Accordingly, the reconstruction of precipitation could be performed using 14C variation in a speleothem formed by drip water with simple flow dynamics.

  8. Utilization of [14C]phenylalanine derived from arylphorin or free amino acid in Manduca sexta pharate adults

    Science.gov (United States)

    Wu, M.; Tischler, M. E.

    1995-01-01

    The role of arylphorin as a storage protein was studied using 14C-arylphorin. 14C-arylphorin was produced optimally by incubating one-half fat body from Manduca sexta fifth instar larvae at 22 degrees C for 24 h, in 1 ml of medium containing amino acids at 25% of their physiological concentration with [U-14C]-phenylalanine (phe) provided initially without nonlabeled phenylalanine. Nonlabeled phe was provided after 1 h at 16% of its physiological concentration. The specific activity of 14C-arylphorin produced in vitro was 30 times greater than that generated in vivo. Injection of 14C-arylphorin into pharate adults was used to study the distribution of 14C-phe derived from this protein into 14CO2 and tissues for comparison with injection of free 14C-phe during the middle (days 6 to 12 pharate adult) and late (days 12 to 17 pharate adult) stages of adult development. Appearance of 14CO2 from 14C-arylphorin as compared to 14C-phenylalanine showed a slower time course during both the middle and late stages of development, in keeping with the time needed for degradation of the protein. In accord with faster phe turnover near the end of adult development, total 14CO2 production was greater and the retention of 14C in hemolymph and fat body was less compared to the middle stage of development regardless of whether 14C-arylphorin or 14C-phe was injected. In the middle stage of development, the appearance of 14C in the cuticle and head parts was greater, whereas incorporation into abdomen and thorax was less than during the late stage of development. Since the pattern of 14C distribution from 14C-arylphorin and 14C-phe was similar, one major function of arylphorin must be as a storage protein replenishing the supply of free amino acids used for synthesis of adult tissues. These results also suggest a limited contribution of M. sexta arylphorin to formation of the cuticle subsequent to day-6 pharate adult.

  9. Remarkable increase in 14C-acetate uptake in an epilepsy model rat brain induced by lithium-pilocarpine.

    Science.gov (United States)

    Hosoi, Rie; Kitano, Daisuke; Momosaki, Sotaro; Kuse, Kenji; Gee, Antony; Inoue, Osamu

    2010-01-22

    The present study demonstrates changes in rat brain glial metabolism during the acute phase of epilepsy. Status epilepticus (SE) was induced using the lithium-pilocarpine model. Glial metabolism was measured with (14)C-acetate. Local cerebral blood flow and glucose metabolism were also measured using (14)C-N-isopropyl-p-iodoamphetamine (IMP) and (14)C-2-deoxyglucose (2DG), respectively. At the initiation of the seizure, (14)C-acetate uptake did not change significantly. However, a marked increase was observed 2 h after the pilocarpine injection in all brain regions studied. The increase of brain uptake was transient, and the maximum enhancement was seen at 2 h after the pilocarpine injection. The increase of (14)C-acetate uptake was almost to the same degree in all regions, whereas (14)C-IMP and (14)C-2DG uptakes showed a heterogeneous increase. In the case of (14)C-IMP, the highest increase was observed in the thalamus (280%), and a moderate increase (120 to 150%) was seen in the orbital cortex, cingulate cortex and pyriform cortex. (14)C-2DG uptake increased by 130 to 240% in most regions of the brain, however, an increase of only 40 and 20% was observed in the cerebellum and pons-medulla, respectively. These results demonstrated that glial energy metabolism was markedly enhanced during a prolonged seizure. To our knowledge, this study is the first observation showing large and widespread glial metabolic increases in the rat brain during status epilepticus.

  10. Clinical diagnostic value of assessment of helicobacter pylori infection with 14C-UBT in gastrointestinal and other diseases

    International Nuclear Information System (INIS)

    Objective: To investigate clinical diagnostic value of assessment of HP infection with 14C-Urea breath test (14C- UBT) in gastrointestinal and other diseases. Methods: The rate of HP infection was detected with 14C-UBT in 2050 patients with gastrointestinal disease, 510 patients with other diseases and 70 healthy controls. Results: (1) The positive rate and rate of moderate and advanced degree of HP infection in patients with gastrointestinal disease were significantly higher than those in controls (86% vs 51%, P14C-UBT is of high sensitivity and specificity. This test is cheap and can be readily performed, and is one of the best methods available. (authors)

  11. Photorespiratory CO/sub 2/ release from l-(U-/sup 14/C)serine in tomato leaves

    Energy Technology Data Exchange (ETDEWEB)

    Yamauchi, M.; Yamada, Y. (Kyushu Univ., Fukuoka (Japan). Faculty of Agriculture)

    1982-04-01

    /sup 14/CO/sub 2/ release from L-(U-/sup 14/C)serine in the illuminated tomato leaf was investigated. Exogenously added (1-/sup 14/C) and (2-/sup 14/C)glycine were metabolized in the glycolate pathway and /sup 14/CO/sub 2/ was evolved at a low CO/sub 2/ concentration from (2-/sup 14/C)glycine in a similar manner to that from L-(U-/sup 14/C)serine (Yamauchi and Yamada, Soil Sci. Plant Nutr., 26, 191-204 (1980)). ..cap alpha..-Hydroxy-2-pyridinemethanesulfonic acid and isonicotinic acid hydrazide increased the (/sup 14/C)glycolate and (/sup 14/C)glycine accumulations, respectively, in leaves fed L-(U-/sup 14/C)serine at a low CO/sub 2/ concentration with a corresponding decrease in /sup 14/CO/sub 2/ evolution. This may indicate that the carbon of serine was recycled back into the Calvin cycle and then incorporated into the glycolate pathway. The /sup 14/CO/sub 2/ release from L-(U-/sup 14/C) serine increased at high light intensity and high temperature. The contribution of CO/sub 2/ release from serine to photorespiration is discussed.

  12. Modeling of irradiated graphite (14)C transfer through engineered barriers of a generic geological repository in crystalline rocks.

    Science.gov (United States)

    Poskas, Povilas; Grigaliuniene, Dalia; Narkuniene, Asta; Kilda, Raimondas; Justinavicius, Darius

    2016-11-01

    There are two RBMK-1500 type graphite moderated reactors at the Ignalina nuclear power plant in Lithuania, and they are under decommissioning now. The graphite cannot be disposed of in a near surface repository, because of large amounts of (14)C. Therefore, disposal of the graphite in a geological repository is a reasonable solution. This study presents evaluation of the (14)C transfer by the groundwater pathway into the geosphere from the irradiated graphite in a generic geological repository in crystalline rocks and demonstration of the role of the different components of the engineered barrier system by performing local sensitivity analysis. The speciation of the released (14)C into organic and inorganic compounds as well as the most recent information on (14)C source term was taken into account. Two alternatives were considered in the analysis: disposal of graphite in containers with encapsulant and without it. It was evaluated that the maximal fractional flux of inorganic (14)C into the geosphere can vary from 10(-11)y(-1) (for non-encapsulated graphite) to 10(-12)y(-1) (for encapsulated graphite) while of organic (14)C it was about 10(-3)y(-1) of its inventory. Such difference demonstrates that investigations on the (14)C inventory and chemical form in which it is released are especially important. The parameter with the highest influence on the maximal flux into the geosphere for inorganic (14)C transfer was the sorption coefficient in the backfill and for organic (14)C transfer - the backfill hydraulic conductivity.

  13. Phosphatase activity in commercial spleen exonuclease decreases the recovery of benzo[a]pyrene and N-hydroxy-2-naphthylamine DNA adducts by 32P-postlabeling.

    Science.gov (United States)

    Adams, S P; Laws, G M; Selden, J R; Nichols, W W

    1994-05-15

    Spleen exonuclease, which degrades nucleic acids into single 3'-nucleotides, is used in the detection of DNA adducts by 32P-postlabeling. Contamination of the exonuclease with phosphatase activity can reduce the recovery of benzo[a]pyrene and N-hydroxy-2-naphthylamine DNA adducts by 32P-postlabeling. Four preparations of spleen exonuclease containing varying levels of phosphatase activity (2-naphthylamine DNA adducts. Surprisingly, recovery of these DNA adducts was nearly 10 times greater using nuclease P1 than when using 1-butanol extraction for adduct enrichment, since arylamine DNA adducts have previously been reported to be poorly detected by 32P-postlabeling after nuclease P1 treatment. Our data indicate that the hydrolysis of DNA by spleen exonuclease may be an important source of variability in both qualitative and quantitative analysis of adducts by 32P-postlabeling. PMID:8059938

  14. Using 14C and 3H to understand groundwater flow and recharge in an aquifer window

    Directory of Open Access Journals (Sweden)

    A. P. Atkinson

    2014-06-01

    14C ages are between 100 and 10 000 years. 3H activities are negligible in most of the groundwater and groundwater electrical conductivity in individual areas remains constant over the period of study. Although diffuse local recharge is evident, the depth to which it penetrates is limited to the upper 10 m of the aquifer. Rather, groundwater in the Gellibrand Valley predominantly originates from the regional recharge zone, the Barongarook High, and acts as a regional discharge zone where upward head gradients are maintained annually, limiting local recharge. Additionally, the Gellibrand River does not recharge the surrounding groundwater and has limited bank storage. 14C ages and Cl concentrations are well correlated and Cl concentrations may be used to provide a first-order estimate of groundwater residence times. Progressively lower chloride concentrations from 10 000 years BP to the present day are interpreted to indicate an increase in recharge rates on the Barongarook High.

  15. Facile and economical preparation of [14C]-labelled Shikimic acid

    International Nuclear Information System (INIS)

    A convenient and inexpensive method for the preparation of [14C]-labelled shikimic acid based on the photoassimilation of 14CO2 by henbane (Hyoscyamus niger L.) leaves in the presence of the herbicide glyphosate is described. Methanolic extracts were purified by successive anion exchange, paper and thin-layer chromatography to yield [14C]-labelled shikimic acid of 99.5% radiochemical purity, as shown by analytical HPLC. Under the conditions employed, the rate of incorporation of 14CO2 into shikimic acid (0.7-17.6%) showed a positive correlation with the size of the leaf used in the incubation (3.6-146 mg fresh weight), while the specific activity of the acid (6-12.7 GBq/mmol) was an inverse function of the leaf size. (author)

  16. Ochratoxin A labelled with /sup 14/C or /sup 3/H in the phenylalanine moiety

    Energy Technology Data Exchange (ETDEWEB)

    Hult, K.

    1986-08-01

    Ochratoxin A is a mycotoxin produced by Aspergillus and Penicillium moulds. The toxin is an amide formed between phenylalanine and the isocoumarin acid ochratoxin ..cap alpha... Ochratoxin A with high specific radioactivity can be obtained, by substitution of the natural phenylalanine for /sup 14/C of /sup 3/H-labelled phenylalanine. Labelled ochratoxin A was formed by condensation of labelled phenylalanine ethylester with an anhydride derivative of ochratoxin ..cap alpha... The intermediate O-acetyl ochratoxin C was hydrolysed with pig liver esterase and chymotrypsin to afford ochratoxin A. The overall yield of radioactivity was 50%. Specific activities up to 500 Ci/mol and 100 ci/mmol for /sup 14/C and /sup 3/H respectively were obtained.

  17. {sup 14}C dating of soil samples from the Unzen volcano scientific drilling boreholes

    Energy Technology Data Exchange (ETDEWEB)

    Xu Sheng E-mail: s.xu@suerc.gla.ac.uk; Hoshizumi, Hideo; Ochiai, Yoji; Aoki, Harumi; Uto, Kozo

    2004-08-01

    Soil samples were collected from the upper layers of two Unzen volcano Scientific Drilling Project boreholes and dated by radiocarbon using accelerator mass spectrometry (AMS). The humic soils underlying volcanic related lahar flow deposits at a depth of 56.42 m of the USDP-1 borehole gave a {sup 14}C age of 18.8 ka BP, suggesting that the accumulation of the lahar flow deposits was caused by the Kureishibaru pyroclastic eruption (19 ka BP) dated at the surface. The humic soils underlying a pyroclastic flow deposit at depths of 71.60-71.90 m of the USDP-2 borehole gave {sup 14}C ages of 27.5 and 29.3 ka BP at the top and bottom layers, respectively. This reveals that the initial activity of Fugendake volcano occurred around 27 ka BP and the collapse of Myokendake volcano around 29 ka BP.

  18. Kinetics of degradation of a biosoluble matrix by 14C tagging

    International Nuclear Information System (INIS)

    Biocompatible, biosoluble matrices are finding use as depots for prolonged release of drugs. The rate of release of the drug immobilized on them is one of the important parameters which may be controlled by the rate of matrix degradation. Cellulose, oxidized with periodate, was shown to be a suitable matrix for a drug depot. The kinetics of solvation of the material was studied spectrophotometrically and by 14C-tagging. Cellulose tagged with 14C was oxidized under standardized conditions and the kinetics of degradation in a Ringer phosphate buffer was followed by measuring the β-activity of the supernatant in a liquid scintillation counter as a function of time. After an initial spurt in release of tagged segments, the rate was practically constant indicating the suitability of such a matrix for a constant and prolonged drug release. Besides, the solubility of the carrier may be modified by controlling the degree of oxidation. (author)

  19. The effect of commercial processing procedures on 14C-monocrotophos residues in soybean oil

    International Nuclear Information System (INIS)

    Soybean plants grown in a field plot were treated with 14C-monocrotophos during the blooming stage. The residues in seeds at harvest were 2.19 ppm, corresponding to 1.04% of the applied dose. The residues in crude oil and cake were 1.78 and 2.30 ppm respectively. After degumming, alkali treatment, bleaching and deodorization, 20% of the original radioactivity in the crude oil was removed. Deodorization was the most effective procedure in removing a considerable part of the residue. Similar processing of oil spiked with 14C-monocrotophos, resulted in near-complete elimination of the residue. This finding suggests that aged residues in oil are different in their nature and do not include monocrotophos. (author). 2 refs, 2 tabs

  20. Further observations on incorporation of the 14C-leucine into proteins by freshly secreted milk

    International Nuclear Information System (INIS)

    Using freshly secreted bovine milk, no incorporation of DL (1-14C)-leucine was observed in the total milk proteins and acid precipitated casein, when these protein fractions were isolated from skim milk. A significant portion of the radioactivity however, remained associated with the heat coagulable whey proteins and proteose-peptone fractions. This association was shown to be due to non enzymatic physical sequestering of the radioactive amino acid or its metabolites with these proteins. Most of the radioactivity was associated with the cream layer proteins and the cellular fraction. The results obtained using filtered milk, incubated milk and certain antibiotics also indicated that the incorporation of 14C leucine into proteins by freshly secreted milk may be a purely microbial process and physical sequestering of an amino acids with milk proteins. (author)

  1. An autoradiographic study on the distribution of 14C-glycine in clonorchis sinensis

    International Nuclear Information System (INIS)

    To study an aspect of protein metabolism in chinese liverfluke, Clonorchis sinensis, an autoradiographic study was performed. A batch of 25 ml erlenmeyer flasks, each flask containing 10 worms of C. sinensis and 10 ml of Tyrode medium with 2.5 μCi/ml of 14C-glycine, was incubated for 1 hour in Dubnoff metabolic shaking incubator at 370C. Those worms were processed for microautoradiography immediately after the incubation, and following results were obtained from the autoradiographs. The densities of black silver grains derived from 14C-glycine were the most apparent in the subparenchymal cells, intestinal epithelium, vitelline gland cells, ovary and the wall of the seminal vesicle. Moderate grade of densities were observed in the tegument, oral sucker, pharynx, intestinal content and in the testes. The reticular tissue, ventral sucker, uterus with eggs, seminal receptacle and the content of seminal vesicle showed trace amount of silver grains. (author)

  2. The radioanalytical determination of cosmogenic 32P in marine samples for the study of the phosphate ion turnover in the mediterranean sea

    International Nuclear Information System (INIS)

    Due to its peculiar half life (14.3 d), cosmogenic 32P can be used for the determination of the phosphate turnover in the oceans. This paper reports the sampling techniques used to collect phytoplankton, zooplankton, particulate matter and to concentrate the dissolved inorganic phosphate (DIP) from large volumes of sea water. Moreover the radioanalytical procedures to isolate 32P and to count the final sources are described. The preliminary results obtained during three different campaignes are finally reported. (orig.)

  3. Comparison of the activity of salt and 35S promoters in transgenic calli of sorghum (Sorghum bicolor L. (Moench))

    International Nuclear Information System (INIS)

    Use of specific promoters under clearly defined conditions in transgenic plants is valuable for determining gene expression. In this study, we used the Salt promoter derived from the rice variety Taichung native-1 and linked to the uidA gene in plasmid pGVB310, and compared its activity with that of the 35S promoter in the transformed calli of sorghum. The 35S promoter, as the constitutive promoter, is also linked to the uidA gene in plasmid p35SGus. Plasmid pGVB310 was transferred to sorghum cell suspension using biolistic bombardment in the same way as co-transformation was carried out for plasmid p35SGus with pROB5 containing the hpt gene as the selectable marker. A transformed callus was selected using 50 mg/L of hygromycin in callus medium for 3 weeks. The resistant colonies obtained during selection were then transferred to a fresh callus medium containint 50 mg/L of hygromycin. A histochemical Gus assay was performed on those calli that were resistant to 50 mg/L of hygromycin; the results showed that a blue colour appeared in the transformed calli after 5 hours of incubation at 37 deg C. A fluorimetric Gus assay was performed to detect quantitative Gus expression in the resistant calli. Resistant calli were grown under various conditions, e.g. 0.1% NaCl, or 2 mg/L of ABA in callus medium, or without stress (normal conditions). The level of promoter activity for both the 35S and Salt promoters was measured on the basis of Gus expression detected with fluorimetric assay. The results showed that the transformed calli (varieties Arval and White Martin) with plasmid pGVB310 showed Gus expression that was about 8-12 times higher than that of the transformed calli with plasmid p35SGus. 2 refs, 1 fig., 1 tab

  4. Dynamics of {sup 14}C-labeled glucose and ammonium in saline arable soils

    Energy Technology Data Exchange (ETDEWEB)

    Vuelvas-Solorzano, Alma; Hernandez-Matehuala, Rosalina [Instituto Tecnologico de Celaya, Celaya Gto. (Mexico). Dept. de Ing. Bioquimica. Lab. de Bioingenieria; Conde-Barajas, Eloy; Cardenas-Manriquez, Marcela [Instituto Tecnologico de Celaya, Celaya Gto. (Mexico). Dept. de Ing. Ambiental. Lab. de Bioingenieria], e-mail: marcela@itc.mx; Luna-Guido, Marco L.; Dendooven, Luc [Centro de Investigacion y de Estudios Avanzados del Instituto Politecnico Nacional (Cinvestav), D.F. (Mexico). Dept. de Biotecnologia y Bioingenieria. Lab. de Ecologia de Suelos], e-mail: dendoove@cinvestav.mx

    2009-07-15

    Organic matter dynamics and nutrient availability in saline agricultural soils of the State of Guanajuato might provide information for remediation strategies. {sup 14}C labeled glucose with or without 200 mg kg{sup -}1 of NH{sub 4} {sup +}-N soil was added to two clayey agricultural soils with different electrolytic conductivity (EC), i.e. 0.94 dS m{sup -}1 (low EC; LEC) and 6.72 dS m{sup -}1 (high EC; HEC), to investigate the effect of N availability and salt content on organic material decomposition. Inorganic N dynamics and production of CO{sub 2} and {sup 14}CO{sub 2} were monitored. Approximately 60 % of the glucose-{sup 14}C added to LEC soil evolved as {sup 14}CO{sub 2}, but only 20 % in HEC soil after the incubation period of 21 days. After one day, < 200 mg {sup 14}C was extractable from LEC soil, but > 500 mg {sup 14}C from HEC soil. No N mineralization occurred in the LEC and HEC soils and glucose addition reduced the concentrations of inorganic N in unamended soil and soil amended with NH{sub 4}{sup +}-N. The NO{sub 2}{sup -} and NO{sub 3}{sup -} concentrations were on average higher in LEC than in HEC soil, with exception of NO{sub 2}{sup -} in HEC amended with NH{sub 4}{sup +}-N. It was concluded that increases in soil EC reduced mineralization of the easily decomposable C substrate and resulted in N-depleted soil. (author)

  5. Bacterial decomposition of synthetic 14C-labeled lignin and lignin monomer derivatives

    International Nuclear Information System (INIS)

    Nocardia sp. which was isolated from soil is capable of degrading synthetic lignin and utilizing its monomer derivatives. Decomposition was monitored by measuring the 14CO2 evolved and O2 consumed, when the bacterium was grown on a medium containing specifically 14C-labeled lignins or monomer phenolic compounds as major carbon source. The time course of the 14CO2 release and O2 uptake indicates a significant depolymerization and utilization of lignin by the Nocardia sp. (author)

  6. Incorporation of 14C-linoleic acid in cerebrosides of psoriatic and normal human skin

    International Nuclear Information System (INIS)

    It was shown that the incorporation of 14C-linoleic acid in cerebrosides of normal and psoriatic human skin is different. In psoriatic epidermis and corium the turnover of this fatty acid is significantly elevated. It is suggested that in psoriasis the epidermal cell is not able to build up a regular carbohydrate sequences of lipids because the false carbohydrate chain activates the degradation of glycolipids and in compensating for the increased degradation raises the synthesis rate of glycolipids. (orig./MG)

  7. A contribution to the comparison of 39Ar and 14C concentrations in the groundwater

    International Nuclear Information System (INIS)

    This study reports about the comparative 39Ar and 14C concentration measurements performed on a sandstone aquifer in the Saarland. From the results a region suitable for the groundwater determination could be established, which also considers the limestone strata covering one water withdrawal site. The effects and influences of a subterranean 39Ar production in such an aquifer can be neglected, since the production ranges below 1% of 39Ar modern. (orig.)

  8. Release of (14C)5-hydroxytryptamine from human platelets by red wine

    International Nuclear Information System (INIS)

    Red wine, at a final dilution of 1/50, caused released of (14C)5-hydroxytryptamine (5-HT) from preloaded platelets, an effect which was not observed with any white wines or beers tested. Since 5-HT, is probably released from body stores during migraine attacks and red wine is known to provoke migraine episodes in susceptible individuals, release of 5-HT, possibly from central stores, could represent a plausible mechanism for its mode of action

  9. Optimization of 14C-lysine concentration and specific activity for the radiometric detection of microorganisms

    International Nuclear Information System (INIS)

    The sensitivity of the radiometric detection of microbial contamination based on the labeling of cells by 14C-lysine was studied as a function of the lysineconcentration and its specific activity for a strain of E. coli and a strain of S. cerevisiae. It was found that best conditions of detection were given by a labelled lysine specific activity of 200 mCsub(i)/mmole and a medium radioactivity of 0.2 μCsub(i)/ml. (orig.)

  10. Applications of the nuclear Techniques in medicine: 13o14C respiration tests

    International Nuclear Information System (INIS)

    The 14C or 13C respiration tests have been applied to the study of metabolic and infectious processes, but most of them have not entered yet the clinical practice stage. In this paper, it is offered an overview of the present and future of respiration tests and how they are taking part and will take part in a future in the non-invasive diagnosis of diverse pathologies

  11. Applications of the nuclear Techniques in medicine: 13C or 14C respiration tests

    International Nuclear Information System (INIS)

    The 14C or 13C respiration tests have been applied to the study of metabolic and infectious processes, but most of them have not entered yet the clinical practice stage. In this paper, it is offered an overview of the present and future of respiration tests and how they are taking part and will take part in a future in the non-invasive diagnosis of diverse pathologies

  12. Using 14C and 3H to understand groundwater flow and recharge in an aquifer window

    Science.gov (United States)

    Atkinson, A. P.; Cartwright, I.; Gilfedder, B. S.; Cendón, D. I.; Unland, N. P.; Hofmann, H.

    2014-12-01

    Knowledge of groundwater residence times and recharge locations is vital to the sustainable management of groundwater resources. Here we investigate groundwater residence times and patterns of recharge in the Gellibrand Valley, southeast Australia, where outcropping aquifer sediments of the Eastern View Formation form an "aquifer window" that may receive diffuse recharge from rainfall and recharge from the Gellibrand River. To determine recharge patterns and groundwater flow paths, environmental isotopes (3H, 14C, δ13C, δ18O, δ2H) are used in conjunction with groundwater geochemistry and continuous monitoring of groundwater elevation and electrical conductivity. The water table fluctuates by 0.9 to 3.7 m annually, implying recharge rates of 90 and 372 mm yr-1. However, residence times of shallow (11 to 29 m) groundwater determined by 14C are between 100 and 10 000 years, 3H activities are negligible in most of the groundwater, and groundwater electrical conductivity remains constant over the period of study. Deeper groundwater with older 14C ages has lower δ18O values than younger, shallower groundwater, which is consistent with it being derived from greater altitudes. The combined geochemistry data indicate that local recharge from precipitation within the valley occurs through the aquifer window, however much of the groundwater in the Gellibrand Valley predominantly originates from the regional recharge zone, the Barongarook High. The Gellibrand Valley is a regional discharge zone with upward head gradients that limits local recharge to the upper 10 m of the aquifer. Additionally, the groundwater head gradients adjacent to the Gellibrand River are generally upwards, implying that it does not recharge the surrounding groundwater and has limited bank storage. 14C ages and Cl concentrations are well correlated and Cl concentrations may be used to provide a first-order estimate of groundwater residence times. Progressively lower chloride concentrations from 10

  13. From 14C/12C measurements towards radiocarbon dating of ice

    NARCIS (Netherlands)

    Oerlemans, J.; Wal, R.S.W. van de; Roijen, J.J. van; Raynaud, D.; Borg, K. van der; Jong, A.F.M. de; Lipenkov, V.; Huybrechts, P.

    1994-01-01

    A dry extraction method of CO2 included in glacier ice adds a contamination equivalent to 1.8 μg modern carbon for a 35 μg C sample. This enables radiocarbon dating by accelerator mass spectrometry of 35 μg C samples to about 25 000 BP. Measured 14C/12C ratios are presented for a part of the Vostok

  14. Biosynthesis of riboflavin. Enzymatic formation of the xylene moiety from [14C]ribulose 5-phosphate.

    Science.gov (United States)

    Nielsen, P; Neuberger, G; Floss, H G; Bacher, A

    1984-02-14

    We have studied the enzymatic formation of the xylene ring of riboflavin using cell extracts from the flavinogenic yeast Candida guilliermondii. 5-Amino-6-ribitylamino-2,4(1H,3H)-pyrimidinedione or its 5'-phosphate could serve as substrates. In addition, a pentose phosphate or pentulose phosphate was required. Experiments with [14C]ribulose 5-phosphate gave evidence for the incorporation of the ribulose carbon atoms except C-4 into the xylene ring of the vitamin. PMID:6546684

  15. Residues of 14C-chlorpyrifos in coconut by radiotracer techniques

    International Nuclear Information System (INIS)

    A coconut tree was root-infused with 5 g a.i. chlorpyrifos (Lorsban plus 1.4 uCi of 14C-chlorpyrifos. Coconut samples both young and mature, were taken 24 h up to 60 days after root infusion. Analysis of the meat and water was done. The maximum uptake of chlorpyrifos equivalents was on the 13th day after root infusion both in mature and young fruit. The residue in water reached the peak on the 20th day after infusion and declined thereafter. A preharvest interval (PHI) of more than 60 days maybe recommended for safe consumption. The usual practice of storing copra in treated warehouses until it is processed into oil was simulated in the laboratory to determine the residues absorbed on the meat. Forty kg of copra with moisture content of 7-12% were stored in an improvised warehouse, i.e. 1 m x 1.5 m x 1 m wooden box, which was treated with 100 ml 1% a.i. Lorsban 50 WP plus 100 uCi 14C-chlorpyrifos for protection against insects. Analysis showed that 14C-chlorpyrifos equivalents ranged from 22.6 mg/kg on the 30th day to 8.2 mg/kg on the 90th day with a 63.7% reduction in residues. Bound residues were detected on samples stored for 60-90 days, with levels of 1.0 to 0.2 ug/g 14 C-chlorpyrifos equivalents. This is within the Maximum Residue Limit of 2 mg/kg set by FAO/WHO for chlorpyrifos in most agricultural commodities. Chlorpyrifos residues were also determined at various stages of refining and processing of crude coconut oil. It was subjected to alkali refining, bleaching and finally steaming. The residues were reduced by as much as 32.7%. (author). 18 refs.; 2 figs.; 3 tabs

  16. In vitro uptake of /sup 14/C-praziquantel by cestodes, trematodes, and a nematode

    Energy Technology Data Exchange (ETDEWEB)

    Andrews, P.; Thomas, H.; Weber, H.

    1980-12-01

    /sup 14/C-praziquantel was rapidly taken up by Schistosoma mansoni, Fasciola hepatica, Hymenolepis nana, and isolated strobilocerci of Taenia taeniaeformis. Schistosoma mansoni lost praziquantel rapidly to drug-free medium. Chromatography of extracts prepared after incubation of S. mansoni and H. nana yielded no indication that praziquantel was metabolized. Autoradiography revealed a uniform distribution of praziquantel throughout the tissues of S. mansoni and H. nana. Uptake was considerably slower in the nematode Heterakis spumosa and apparently via the oral route.

  17. Assimilation of 14CO2 and 14C sucrose by citrus fruit tissues

    International Nuclear Information System (INIS)

    Assimilation and metabolism of 14CO2 was compared to that of [U-14C] sucrose in young grapefruit (ca 25 mm diameter) to determine their respective roles in fruit growth. Fixation of 14CO2 by isolated fruit tissues during 10 min in light exceeded that in dark by 2- to 30-fold depending on tissue content of chlorophyll. Greatest apparent photosynthesis occurred in outer green peel, but green juice tissues assimilated more than did adjoining inner peel tissue. In the dark, juice tissues incorporated 2.5-fold more 14CO2 than any other tissue. Neutral sugars accounted for a smaller proportion and organic acids, a greater proportion, of the 14C-assimilates in interior peel and juice tissues. These data suggest more extensive production of organic acids from 14CO2 in tissues isolated from the fruit interior. In contrast, little difference among tissues was evident in extent of organic- and amino-acid production from exogenous [U-14C] sucrose. A small area of cuticle on whole fruit was replaced by a filter disc impregnated with radiolabeled sucrose and incubated for 16 h. Thus, carbon derived from CO2 assimilation by fruit appears to be partitioned differently than that derived from sucrose

  18. Cluster Decay of the High-lying excited states in $^{14}$C

    CERN Document Server

    Tian, Z Y; Li, Z H; Lin, C J; Li, Q T; Ge, Y C; Lou, J L; Jiang, W; Li, J; Yang, Z H; Feng, J; Li, P J; Chen, J; Liu, Q; Zang, H L; Yang, B; Zhang, Y; Chen, Z Q; Liu, Y; Sun, X H; Ma, J; Jia, H M; Xu, X X; Yang, L; Ma, N R; Sun, L J

    2016-01-01

    A cluster-transfer experiment of $^9\\rm{Be}(^9\\rm{Be},^{14}\\rm{C}\\rightarrow\\alpha+^{10}\\rm{Be})\\alpha$ at an incident energy of 45 MeV was carried out in order to investigate the molecular structure in high-lying resonant states in $^{14}$C. This reaction is of extremely large $Q$-value, making it an excellent case to select the reaction mechanism and the final states in outgoing nuclei. The high-lying resonances in $^{14}$C are reconstructed for three sets of well discriminated final states in $^{10}$Be. The results confirm the previous decay measurements with clearly improved decay-channel selections and show also a new state at 23.5(1) MeV. The resonant states at 22.4(3) and 24.0(3) MeV decay primarily into the typical molecular states at about 6 MeV in $^{10}$Be, indicating a well developed cluster structure in these high-lying states in $^{14}$C. Further measurements of more states of this kind are suggested.

  19. Human urinary excretion profile after smoking and oral administration of [14C]delta 1-tetrahydrocannabinol

    International Nuclear Information System (INIS)

    The urinary excretion profiles of delta 1-tetrahydrocannabinol (delta 1-THC) metabolites have been evaluated in two chronic and two naive marijuana users after smoking and oral administration of [14C]delta 1-THC. Urine was collected for five days after each administration route and analyzed for total delta 1-THC metabolites by radioactivity determination, for delta 1-THC-7-oic acid by high-performance liquid chromatography, and for cross-reacting cannabinoids by the EMIT d.a.u. cannabinoid assay. The average urinary excretion half-life of 14C-labeled delta 1-THC metabolites was calculated to be 18.2 +/- 4.9 h (+/- SD). The excretion profiles of delta 1-THC-7-oic acid and EMIT readings were similar to the excretion profile of 14C-labeled metabolites in the naive users. However, in the chronic users the excretion profiles of delta 1-THC-7-oic acid and EMIT readings did not resemble the radioactive excretion due to the heavy influence from previous Cannabis use. Between 8-14% of the radioactive dose was recovered in the urine in both user groups after oral administration. Lower urinary recovery was obtained both in the chronic and naive users after smoking--5 and 2%, respectively

  20. Comparison of different soil organic matter fractionation methodologies: Evidences from ultrasensitive {sup 14}C measurements

    Energy Technology Data Exchange (ETDEWEB)

    Marzaioli, Fabio, E-mail: fabio.marzaioli@unina2.i [CIRCE, Dipartimento di Scienze Ambientali, Seconda Universita degli studi di Napoli and INNOVA, Via Vivaldi, 43, Caserta 81100 (Italy); Lubritto, Carmine; Galdo, Ilaria Del; D' Onofrio, Antonio [CIRCE, Dipartimento di Scienze Ambientali, Seconda Universita degli studi di Napoli and INNOVA, Via Vivaldi, 43, Caserta 81100 (Italy); Cotrufo, M. Francesca [CIRCE, Dipartimento di Scienze Ambientali, Seconda Universita degli studi di Napoli and INNOVA, Via Vivaldi, 43, Caserta 81100 (Italy); Department of Soil and Crop Sciences, Colorado State University, Fort Collins, Colorado (United States); Terrasi, Filippo [CIRCE, Dipartimento di Scienze Ambientali, Seconda Universita degli studi di Napoli and INNOVA, Via Vivaldi, 43, Caserta 81100 (Italy)

    2010-04-15

    Soils are studied with the aim to predict future climatic scenarios and find the best guidelines to manage terrestrial ecosystems for the mitigation of the atmospheric CO{sub 2} rising. Carbon constituting soil organic matter (SOM) behaves as a cohort of different pools, characterized by a specific C turnover time. Both natural and anthropogenic occurring {sup 14}C reach the soil through plant littering, becoming a valid tool to trace SOM dynamics. In this study we present a series of Accelerator Mass Spectrometry (AMS) {sup 14}C measurements on SOM samples obtained by means of different laboratory protocols used for the isolation of soil pools from bulk soil (fractionation protocols). Radiocarbon signature of SOM fractions is used as a keyhole to look at the more effective fractionation procedure and comparison among measured {sup 14}C on SOM fractions revealed important indications for the proposal of a novel fractionation protocol. Our data put in evidence how particle size controls the recalcitrance of ancient SOM carbon pools.

  1. Methods for high precision 14C AMS measurement of atmospheric CO2 at LLNL

    Energy Technology Data Exchange (ETDEWEB)

    Graven, H D; Guilderson, T P; Keeling, R F

    2006-10-18

    Development of {sup 14}C analysis with precision better than 2{per_thousand} has the potential to expand the utility of {sup 14}CO{sub 2} measurements for carbon cycle investigations as atmospheric gradients currently approach traditional measurement precision of 2-5{per_thousand}. The AMS facility at the Center for Accelerator Mass Spectrometry, Lawrence Livermore National Laboratory, produces high and stable beam currents that enable efficient acquisition times for large numbers of {sup 14}C counts. One million {sup 14}C atoms can be detected in approximately 25 minutes, suggesting that near 1{per_thousand} counting precision is economically feasible at LLNL. The overall uncertainty in measured values is ultimately determined by the variation between measured ratios in several sputtering periods of the same sample and by the reproducibility of replicate samples. Experiments on the collection of one million counts on replicate samples of CO{sub 2} extracted from a whole air cylinder show a standard deviation of 1.7{per_thousand} in 36 samples measured over several wheels. This precision may be limited by the reproducibility of Oxalic Acid I standard samples, which is considerably poorer. We outline the procedures for high-precision sample handling and analysis that have enabled reproducibility in the cylinder extraction samples at the <2{per_thousand} level and describe future directions to continue increasing measurement precision at LLNL.

  2. Pollen-based biomes for Beringia 18,000, 6000 and 0 14C yr BP

    Science.gov (United States)

    Edwards, M.E.; Anderson, P.M.; Brubaker, L.B.; Ager, T.A.; Andreev, A.A.; Bigelow, N.H.; Cwynar, L.C.; Eisner, Wendy R.; Harrison, S.P.; Hu, F.-S.; Jolly, D.; Lozhkin, A.V.; MacDonald, G.M.; Mock, C.J.; Ritchie, J.C.; Sher, A.V.; Spear, R.W.; Williams, J.W.; Yu, G.

    2000-01-01

    The objective biomization method developed by Prentice et al. (1996) for Europe was extended using modern pollen samples from Beringia and then applied to fossil pollen data to reconstruct palaeovegetation patterns at 6000 and 18,000 14C yr BP. The predicted modern distribution of tundra, taiga and cool conifer forests in Alaska and north-western Canada generally corresponds well to actual vegetation patterns, although sites in regions characterized today by a mosaic of forest and tundra vegetation tend to be preferentially assigned to tundra. Siberian larch forests are delimited less well, probably due to the extreme under-representation of Larix in pollen spectra. The biome distribution across Beringia at 6000 14C yr BP was broadly similar to today, with little change in the northern forest limit, except for a possible northward-advance in the Mackenzie delta region. The western forest limit in Alaska was probably east of its modern position. At 18,000 14C yr BP the whole of Beringia was covered by tundra. However, the importance of the various plant functional types varied from site to site, supporting the idea that the vegetation cover was a mosaic of different tundra types.

  3. Evaluation of errors in the 14C method of primary production measurement

    International Nuclear Information System (INIS)

    Membrane filtration is an integral part of the 14C method of measuring primary productivity in natural waters. Polycarbonate, cellulose ester, and glass-fiber filters retan about 0.0003, 0.09, and 0.24 mg water per mm2 surface area. The [14C]bicarbonate in this retained water must be eliminated before the filter is assayed for radioactivity. Airdrying, desiccator-drying in the presence or absence of a CO2 absorbant, and oven-drying are only partially effective decontamination procedures; washing with pH 2 filtered lake water removes most of the contaminating activity. A plot (dpm.filter-1 vs. volume filtered) is used to diagnose the efficiency of decontamination. A simple and safe decontamination procedure is shown to eliminate effectively all residual [14C]bicarbonate activity. Membrane filters are placed in scintillation vials, 0.1 to 1.0 ml of 0.5 N HCl is added, and, after a 2 to 3-h interval, the scintillation fluor is added

  4. Na/sup +/-dependent transport of /sup 14/C-L-lysine across bullfrog alveolar epithelium

    Energy Technology Data Exchange (ETDEWEB)

    Kim, K.J.; Crandall, E.D.

    1986-03-01

    Transepithelial transport of the basic amino acid L-lysine has been studied utilizing the isolated intact bullfrog lung mounted in the Ussing chamber. Lungs were excised from doubly pithed bullfrogs and sandwiched between two hemichambers. /sup 14/C-(U)-L-lysine was added to the upstream reservoir of amphibian Ringer solution, while the tissue was short-circuited. Two lungs from the same animal were used simultaneously to determine the two opposite unidirectional fluxes. Downstream and upstream radioactivities were assayed and used to estimate the apparent permeability (P) of the labeled lysine. Results indicate that the apparent P of /sup 14/C-L-lysine measured in the alveolar (M) to the pleural (S) direction is 19.06 (+- 2.84) x 10/sup -7/ cm/s and P in the S to M direction is 3.29 (+- 0.02) x 10/sup -7/ cm/s. When the 100 mM NaCl in the bath was replaced by 110 mM choline chloride, the flux of /sup 14/C-L-lysine from the alveolar to the pleural side decreased to the same value as that in the opposite direction. The flux from the pleural to the alveolar direction in the absence of Na/sup +/ did not change. These results suggest that the alveolar epithelium exhibits Na/sup +/-dependent amino acid (L-lysine) transport in the M->S, but not in the S->M, direction.

  5. Results of 14C analysis on low-level reference materials

    International Nuclear Information System (INIS)

    An invitation from the University of Glasgow to participate in an international intercomparison of 14C analysis and the increased need for quality assurance for measurements performed at the Low-Level Laboratory by AECL's Environmental Technologies Branch (ETB), Chalk River Laboratories, prompted the initiation of this work. Standard 14C samples from the IAEA and from the ETB were analyzed and compared to their reference values. All analyses agreed well with reported values and confirmed that the ETB can reliably measure 14C between 50 and 500 Bq/kg C. Samples from the University of Glasgow, Scotland, were also analyzed and reported. The results of counting various CO2 blank materials (dry ice from a CO2-siphon and limestone) showed that the source of CO2 does not have an effect on background count rate or counter efficiency. The ETB's lower limit of detection (LLD) has been calculated to be 10 -20 Bq/kg C and the determination limit (LQ) for samples during the ETB's routine operations has been documented to be 44 Bq/kg C. (author)

  6. Validation of {sup 14} C-urea breath test for diagnosis of Helicobacter pylori

    Energy Technology Data Exchange (ETDEWEB)

    Mattar, Rejane; Silva, Fernando Marcuz; Alexandrino, Ana Maria; Laudanna, Antonio Atilio [Sao Paulo Univ., SP (Brazil). Hospital das Clinicas. Dept. de Gastroenterologia]. E-mail: shiroineko@uol.com.br

    1999-02-01

    The aim of this study was to validate the {sup 14} C-urea breath test for use in diagnosis of Helicobacter pylori infection. Thirty H. pylori positive patients, based on histologic test and thirty H. pylori negative patients by histology and anti-H pylori IgG entered the study. Fasting patients drank 5 uCi of {sup 14} C-urea in 20 ml of water. Breath samples were collected at O, 5, 10, 15, 20 and 30 min. The difference of cpm values between the two groups was significant at all the time intervals, besides time 0 (p < 0.0001). At 20 min, the test gave 100% sensitivity and specificity with a cut-off value of 562 cpm. Females were higher expirers than males (p=0.005). {sup 14} C-urea breath test is highly accurate for Helicobacter pylori diagnosis. It is fast, simple and should be the non-invasive test used after treating Helicobacter pylori infection. (author)

  7. Persistence and distribution of [14C]-lindane residues in coffee plants

    International Nuclear Information System (INIS)

    Studies on weathering, volatilization, absorption, translocation and accumulation of [14C]-lindane (γ-1,2,3,4,5,6-hexachlorocyclohexane) in coffee (Coffeea arabica L. var. Bourbon) plants are reported. Ten days after topical application to the leaf surface the insecticide can be absorbed and translocated to different parts of the plant. It accumulates mainly in the roots and appears in other leaves. In these experiments, when plants are cultivated in nutrient solution, release of radiocarbon through roots could be detected, indicating exchange of labelled material between plant and surrounding media. When the insecticide is supplied to coffee plants through the roots immersed in nutrient solution containing [14C]-lindane, the labelled material is absorbed and, after 24 hours, radioactive material can be detected in young leaves of the upper parts of the plant. Loss of [14C]-lindane by volatilization, evaporation and co-distillation with water is apparently continuous and represents a significant proportion of that applied. (author)

  8. 14C and tritium dynamics in wild mammals: a metabolic model

    International Nuclear Information System (INIS)

    The protection of biota from ionising radiations needs reliable predictions of radionuclide dynamics in wild animals. Data specific for many wild animals radionuclide combinations is lacking and a number of approaches including allometry have been proposed to address this. However, for 14C and tritium, which are integral components of animals tissues and their diets, a different approach is needed in the absence of experimental data. Here we propose a metabolically based model which can be parameterized predominantly on the basis of published metabolic data. We begin with a metabolic definition of the 14C and OBT loss rate (assumed to be the same) from the whole body and also specific organs, using available information on field metabolic rate and body composition. The mammalian body is conceptually partitioned into compartments (body water, viscera, adipose, muscle, blood and remainder) and a simple model defined using net maintenance and growth needs of mammals. Intake and excretion, and transfer to body water are modelled using basic metabolic knowledge and published relationships. The model is tested with data from studies using rats and sheep. It provides a reliable prediction for whole body and muscle activity concentrations without the requirement for any calibration specific to 3H and 14C. Predictions from the model for representative wild mammals (as selected to be reference organisms within international programmes) are presented. Potential developments of a metabolic model for birds and the application of our work to human food chain modelling are also discussed. (author)

  9. Enantioselective absorption and transformation of a novel chiral neonicotinoid [(14)C]-cycloxaprid in rats.

    Science.gov (United States)

    Wu, Chengchen; Huang, Lei; Tang, Shenghua; Li, Zhong; Ye, Qingfu

    2016-06-01

    Neonicotinoid pesticides caused hazardous effects on pollinators and aquatic ecosystem. The new developed chiral cis-neonicotinoid cycloxaprid(CYC) is a highly potent substitute for low toxicity to bees and high efficiency on target-insects, but little is known about the metabolic dynamics of racemic CYC and its 2 enantiomers(SR and RS) in animal models. In this study, chiral separation of (14)C-labeled racemic CYC was performed in high-performance liquid chromatography under optimal conditions. For the first time that the stereoselectivity of the chiral neonicotinoid insecticide CYC was exhibited in rats after single dose oral administration using (14)C-labeled isotope trace technique. Enantioselective behaviors of racemic CYC, SR and RS were observed in blood metabolism, tissue distribution and excretion. The major deposition of (14)C were found in liver, lung, kidney and heart. After 24 h, skin and fat showed a strong bioaccumulation effect, and total excreted urine and feces of CYC, SR and RS were 50.4%, 59.7% and 74.5%, respectively. Enantiomer RS had the fastest absorption and elimination rates, and it was least bioaccumulated in rats. The results provide scientific basis and practical techniques for environmental risk assessment of chiral pesticides, especially neonicotinoids. PMID:27038208

  10. 14C-Zineb Residues in Sunflower Seeds and Oils and the Effect of Processing

    International Nuclear Information System (INIS)

    The fungicidal Zineb and some of its degradation products have been prepared for the present investigation. Following application of 14C-labelled compound in the rate of 250 g,500 g, and 1000 g per feddan on sunflower plants (2 applications/ each dose at seeds formation stage), the levels of 14C-residues in seeds, oil and cake were determined. The amount of residues recovered in seeds was found to be dose dependent. Their distribution in different samples ranged from 9-12% in oil, 19-20% in methanol extract and 48-52% in the cake. Chromatographic analysis of crude oil (hexane extract) revealed the presence of the parent compound together with four metabolites, which were identified by chromatography with authentic compounds. Methanol extraction of the cake revealed the presence of 3 other metabolites, one of them is unknown. The effect of processing methods used for oil refining on the fungicide residue levels was studied. Obvious reduction was detected by neutralization (13.7%) and was increased by further bleaching (34.1%), winterization (41.46%) and deodorization (53.6%) methods. When rats were fed the extracted seeds, the bound residues were found to be considerably bioavailable. From the 14C-activity in the feed, 72.3% was extracted in the urine and 21.1% were recovered in the feces

  11. Role of biotransformation, sorption and mineralization of (14)C-labelled sulfamethoxazole under different redox conditions.

    Science.gov (United States)

    Alvarino, T; Nastold, P; Suarez, S; Omil, F; Corvini, P F X; Bouju, H

    2016-01-15

    (14)C-sulfamethoxazole biotransformation, sorption and mineralization was studied with heterotrophic and autotrophic biomass under aerobic and anoxic conditions, as well as with anaerobic biomass. The (14)C-radiolabelled residues distribution in the solid, liquid and gas phases was closely monitored along a total incubation time of 190 h. Biotransformation was the main removal mechanism, mineralization and sorption remaining below 5% in all the cases, although the presence of a carbon source exerted a positive effect on the mineralization rate by the aerobic heterotrophic bacteria. In fact, an influence of the type of primary substrate and the redox potential was observed in all cases on the biotransformation and mineralization rates, since an enhancement of the removal rate was observed when an external carbon source was used as a primary substrate under aerobic conditions, while a negligible effect was observed under nitrifying conditions. In the liquid phases collected from all assays, up to three additional peaks corresponding to (14)C-radiolabelled residues were detected. The highest concentration was observed under anaerobic conditions, where two radioactive metabolites were detected representing each around 15% of the total applied radioactivity after 180 h incubation. One of the metabolites detected under anoxic and anaerobic conditions, is probably resulting from ring cleavage of the isoxazole ring. PMID:26546766

  12. Distribution of 14C-chlorsulfuron bound residues in soil organicmatter

    Institute of Scientific and Technical Information of China (English)

    1999-01-01

    The reason why chlorsulfuron (2-chloro-N-[4-methoxy-6-methyl-1,3,5-triazin-2-yl)amino]carbonyl]benzenesulfonamide)bound residues can stillmake an injury to rotational crops is still keptunknown. The experiment was conducted under laboratory conditions to determine thedynamics ofextractable and non-extractable (bound) residues of chlorsulfuron in soil, and the distribution ofchlorsulfuron bound residues in organic matter fractions. The resultsshowed that extractable 14C-residuesdecreased to 25.12% of applied chlorsulfuron over an incubation period of 150 days; this in turn, theformation of bound residues increased to 47.07% of the applied. Theproportions of 14C-bound residues in soilorganic matter fractions increase in order of: humic acid(HA)14C-chlorsulfuron bound residues can still make an injury torotational crops.

  13. Biochemical and morphological studies on the percutaneous uptake of [14C] ethylenediamine in the rat

    International Nuclear Information System (INIS)

    Male Wistar rats were exposed to aqueous [14C]ethylenediamine (EDA) solutions (10, 25, or 50%) percutaneously over a 7 x 7 cm area on the back with occlusion for 24 h. For each rat dosed, three types of studies were conducted: (1) plasma kinetics, (2) material balance, and (3) histological evaluation, including autoradiography of the skin sample from the dosing area. Adequate kinetic measurements were obtained only from animals treated with 25 and 50% EDA, but not from the 10% treatment group, due to analytical limitations. The uptake of [14C]EDA percutaneously by the rat was relatively slow in comparison with uptake following peroral or endotracheal administration. The absorption of EDA by the animals was estimated to be greater than 61, 55, and 12%, respectively, for the 50, 25, and 10% treatment groups. A large portion (11-32%) of the dose was left on/in the dosing area. Urinary excretion was the predominant route for the disposition of EDA. The recovery of the administered dose was low (70-83%), possibly due to volatilization of EDA from the skin during dosing and holding. Histologic examination of skin sections (dosing areas) revealed a normal, intact epidermis in rats dosed with 10% EDA, but full-thickness epidermal necrosis in rats dosed with 25% or 50% EDA solutions. The damage of the epidermis apparently enhanced the penetration of EDA. Autoradiographic preparations revealed a concentration of the [14C]EDA radiolabel over the keratin layer and hair shafts

  14. Design and characterization of a 32P-patch for the treatment of skin diseases. Studies of its application as a betatherapeutic agent for modulated brachytherapy

    International Nuclear Information System (INIS)

    The purpose of this work was to design and evaluate a 32P-patch for contact brachytherapy of skin diseases. [32P]-chromic phosphate in combination with silicone was employed to produce the designed 32P patch. Radiopharmaceutical production was carried out in accordance with radiological safety issues. To verify the safety of the 32P-patch, stability studies in vitro and in vivo were carried out to evaluate the leakage of radioactivity and autoradiographic studies were performed to evaluate the dose homogeneity and shielding. Therapeutic efficacy in animal models of skin cancer as well as in cats with squamous cell carcinoma was evaluated. These results showed that independently of the considered model, tumor growth was arrested and complete regressions were achieved in some other cases. Radiation doses were estimated with equations derived from the MIRD DOSE scheme and compared with Monte Carlo β doses. Some advantages of the designed 32P-patch allow its use for conformal and modulated radiotherapy such as the possibility of modifying the activity concentration of the patch, the limited range of β- radiation, dose deep distribution and combination with bolus. This 32P-patch which is easy to prepare and control may be used in the treatment of skin diseases alone or in combination with other treatment modalities. (author)

  15. Does the 14C method estimate net photosynthesis? II. Implications from cyclostat studies of marine phytoplankton

    Science.gov (United States)

    Pei, Shaofeng; Laws, Edward A.

    2014-09-01

    Two species of marine phytoplankton, Isochrysis galbana and Chlorella kessleri, were grown in a continuous culture system on a 12-h:12-h light:dark cycle of illumination under nitrate-limited growth conditions. At growth rates of ~1 d-1, production rates estimated from 14C uptake were not significantly different from production rates estimated from changes in particulate organic carbon (POC) and total organic carbon (TOC). At growth rates of ~0.35 d-1, however, production rates based on uptake of 14C significantly (p<0.05) overestimated production rates based on changes in POC and TOC in all cases for C. kessleri and after 24 h for I. galbana. The ratio of production based on 14C uptake to production based on changes in POC and TOC concentrations was in all cases higher after 24 h than after 12 h. The extent of overestimation after a 24-h incubation at ~0.35 d-1 was about 23 and 40% in the cases of I. galbana and C. kessleri, respectively. Dark respiration rates estimated from changes in 14C activity during the dark period were lower than the rates estimated from changes of POC and TOC concentrations during the 12 h of darkness because only about 73% of the carbon respired during the dark period had been fixed during the previous 12-h photoperiod. The fact that the 14C method tends to overestimate net carbon assimilation by a greater percentage at low growth rates than at high growth rates probably reflects the greater efficiency of intracellular recycling of respired CO2 at high growth rates. The fact that the extent of overestimation is greater when cells are grown on a light:dark cycle probably reflects the fact that not all carbon respired in the dark was fixed during the previous photoperiod and that intracellular recycling of respired CO2 during the photoperiod is inefficient during some phases of the synchronized growth that tends to be entrained by light:dark cycles.

  16. Environmental 14C and 3H activities: global trends and local contamination

    International Nuclear Information System (INIS)

    The anthropogenic disturbance of natural distributions of radiocarbon ( 14C) and tritium (3H) due to the release of bomb-produced isotopes occurred after the World War II and at the same time the monitoring of these isotopes started at several stations in the world. Radioactive isotopes 14C and 3H, together with the stable isotopes 2H and 18O, are very important tracers in environmental, climatological and hydrological studies. Monitoring of environmental levels of 14C and 3H in Croatia started more then 20 years ago, while that of the stable isotopes somewhat later. The monitoring was performed at the three types of stations: a) 'clean-air' sites, which are supposed to reflect only the global disturbance of the atmospheric isotope concentrations, b) in a densely populated industrial center, where the effect of intense fossil-fuel combustion is expected, and local contamination from institutions using radioactive-labeled material is also possible, and c) at locations around the Nuclear Power Plant Krsko. The mean yearly 3H activities in precipitation continuously decrease since the beginning of monitoring approaching slowly the natural equilibrium. The monthly 3H activities show seasonal variations, with maximum in early summer and minimum in early winter. Both seasonal variations and the decrease of the mean yearly values are typical for continental stations of the Northern Hemisphere. At the sampling site located at the Institute, several periods of higher 3H activities were observed, due to the local contamination with the tritium-labeled material. The 14C concentration in the atmosphere shows also the continuous decrease of the mean yearly values and superposed seasonal fluctuations, with higher activity during summer. Seasonal peak-to-peak variations are higher in the area of the city of Zagreb than at the clean-air site on the mountain (about 1000 m a.s.l.). This difference is caused by the introduction of CO2 (containing no 14C isotope) produced by fossil

  17. Methods for treating and conditioning of 14C containing health care waste

    International Nuclear Information System (INIS)

    Health care radioactive waste was previously accepted at Necsa and disposed of on this site in near-surface trenches. This practice was terminated by the regulator during 1997 and since then waste drums have been stored and have now become a Necsa liability. These waste drums containing unknown quantities of 14C. About 2500 drums have been accumulated over the years at the Necsa site. The 14C and 3H contents could not be determined with non-destructive assay methods. A study to minimize the further accumulation of 14C containing health care waste was undertaken and some new regulations implemented to prevent further increase of the liability.The bio-hazardous nature of the waste proved to be the main complication in the development of appropriate characterization and conditioning methods. Possible methods to sterilize the waste as a first step were consequently investigated, and this regards two interesting options received attention. The first was the so-called Stericycle ETD process, during which the waste is shredded in an enclosed environment and then sterilized by means of a technique known as Electro Thermal De-activation, and the second was sterilization with Gamma rays. The latter method had the advantage that shredding and repacking were not required.Once the waste was sterilized the waste could be characterized. The most practical method to do this was to compact the drum in a supercompactor and to analyze the liquid released from the drum during compaction in a laboratory.Reasonably accurate estimates of the 14C contents of the waste packages were obtained in this way and at the same time the waste volume to be disposed of was reduced by at least a factor of four. The option to dispose of the waste without doing any quantification of the 14C was also investigated. This option does not require the waste drums to be opened and therefore no sterilization is required. Characterization is in this case limited to assaying the drums for nuclides that can be

  18. Synthesis of [5,6-13C2, 1-14C]olivetolic acid, methyl [1'-13C]olivetolate and [5,6-13C2, 1-14C]cannabigerolic acid

    International Nuclear Information System (INIS)

    Potential advanced intermediates in the biosynthesis of delta9-tetrahydrocannabinol, the major psychoactive principle of marijuana, have been synthesized labeled with two contiguous 13C atoms and 14C. Methyl [5,6-13C2, 1-14C]olivetolate was prepared from lithium [13C2]acetylide and dimethyl [2-14C]malonate. Reaction with geranyl bromide afforded methyl [5,6-13C2, 1-14C]cannabigerolate, and hydrolysis of these methyl esters with lithium propyl mercaptide yielded the corresponding labeled acids. The 13C-13C couplings observable in the 13C NMR spectra of these 13C-enriched compounds and their synthetic precursors are recorded. Methyl [1'-14C]olivetolate was prepared from 13CO2 to confirm assignments of the 13C chemical shifts in the pentyl side chain of these compounds. (author)

  19. Synthesis of 7-[α-(2-amino-[2-14C]thiazol-4-yl)-α-(Z)-methoxyimin oacetamido]-3-(1-methylpyrrolidinio)methyl-3-cephem-4-carboxylate hydrochloride ([14C]cefepime hydrochloride)

    International Nuclear Information System (INIS)

    The title compound ([14C]cefepime hydrochloride) was prepared as follows:- [14C]Thiourea was condensed with ethyl 4-bromo-3-oxo-2-methoxyimino-acetate providing ethyl 2-(2-amino-4-[2-14C] thiazolyl)-2-methoxyi-minoacetate as the pure Z-isomer. Saponification gave the amino acid this was reacted with 1-hydroxybenzotriazole to give the activated ester. Condensation in situ with 7-amino-3-(1-methylpyrrolidinio) methyl-3-cephem-4-carboxylate yielded the product as the pure sulfate salt. Treatment of the sulfate salt with base provided the zwitterion isolated as the stable N-methyl-2-pyrrolidinone adduct. An aqueous solution of the adduct was converted to the crystalline title compound, [14C]Cefepime hydrochloride hydrate, with hydrochloric acid/acetone. Radiochemical purity was 99.0% and specific activity, 34.2 μCi/mg. Overall yield from [14C]thiourea was 18%. (Author)

  20. Application of biotinylated and 32P probes for detection of P-fimbriae in urinary E. coli.

    Science.gov (United States)

    Jusková, E; Ciznár, I

    1993-01-01

    Escherichia coli is the common causative agent of urinary tract infections. Twenty-six strains of Escherichia coli were isolated from children with pyelonephritis, symptomatic urinary tract infections and asymptomatic bacteriuria. Biotinylated and 32P-DNA probes were prepared for detection of P-fimbriae in the isolates. Of the 13 strains isolated from patients with pyelonephritis 11 were positive for the presence of the P gene by both probes. Strains isolated from cases of symptomatic urinary tract infections revealed the presence of P gene only in three samples of the total of nine isolated. None of the isolated E. coli strains from asymptomatic bacteriuria was found positive for the presence of the P gene. The biotinylated probe was simple and easily applicable in standard laboratory conditions and therefore the authors recommend it for use in diagnostic laboratories.

  1. Formation and persistence of sterigmatocystin-DNA adducts in rat liver determined via 32P-postlabeling analysis

    International Nuclear Information System (INIS)

    A 32P-postlabeling method has been employed to detect the in vitro and in vivo modification of DNA by the mycotoxin sterigmatocystin (ST). Dose-dependent ST-DNA adduct formation was detected in the liver of male Fischer 344 rats over a 27-fold range of ST administered. In addition, ST-DNA adducts, formed in rats given a 9 mg/kg dose, were found to persist up to 105 days after treatment at a level of 0.5% of the 2-h value. Loss of these adducts from liver DNA was observed to exhibit a triphasic profile: rapid loss during the first 24 h followed by a slower decline from 1 to 14 days post dosing and an extremely slow decline from day 14 to 105 post treatment. This experimental approach to the study of mycotoxin-DNA interactions permits the quantitative description of DNA modification in ST-treated animals. (Auth.)

  2. Efficiency of phosphate fertilization to maize crop in high phosphorus content soil, evaluated by {sup 32}P tracer

    Energy Technology Data Exchange (ETDEWEB)

    Trevizam, Anderson R.; Alvarez Villanueva, Felipe C.; Silva, Maria Ligia de S.; Muraoka, Takashi [Centro de Energia Nuclear na Agricultura (CENA), Piracicaba, SP (Brazil). Lab. de Fertilidade do Solo]. E-mails: trevizam@cena.usp.br; falvarez@cena.usp.br; mlsousi@hotmail.com; muraoka@cena.usp.br

    2007-07-01

    Application of high dosis of phosphorus (P) in agricultural soils is justified by its intense fixation by the soil clays, which reduce availability to crops. The objective of this research was to evaluate the response of maize crops to five rates of triple superphosphate in a soil with high available phosphorus content. Portions of 2 dm{sup 3} of soil (Typic Quartzipisamment) with 75 mg kg{sup -1} of available phosphorus and pH 7.00, collected from the upper 0-20 cm layer, were placed in plastic pots, received solution containing 5.55 MBq (150 {mu}Ci) of {sup 32}P and incubated for 7 days. Then 0, 250, 500, 1000 and 4000 mg P kg{sup -1} as triple superphosphate was added to soil in the respective pots and incubated for 15 days keeping the soil moisture to 60 % of the field capacity. Maize (Zea mays L.) plants, single hybrid P30F80, were grown for 50 days (after germination), collected, oven dried, weighed and ground in a Wiley mill for analysis of total P content and {sup 32}P radioactivity. The maize dry matter increased with triple superphosphate rates. The phosphorus content and accumulation in the maize plants increased with triple superphosphate rate up to 4000 mg kg{sup -1}. The percentage of phosphorus derived from the fertilizer ranged from 79 to 97% and consequently the phosphorus derived from soil decreased with increasing application of triple superphosphate. In spite of soil high P available content, maize plants responded to applied phosphorus rates. (author)

  3. 32P-postlabelling analysis of dibenz[a,j]acridine-DNA adducts in mice: identification of proximate metabolites.

    Science.gov (United States)

    Talaska, G; Roh, J; Schamer, M; Reilman, R; Xue, W; Warshawsky, D

    1995-03-30

    N-Heterocyclic polynuclear aromatics are widely-occurring environmental pollutants formed during the pyrolysis of nitrogen-containing organic chemicals. Dibenz[a,j]acridine (DBA), a member of this class, has been shown to be a skin carcinogen in mice. We undertook studies to determine the organ distribution of DBA-DNA adducts and to identify the DBA metabolites which lead to the formation of carcinogen-DNA adducts in vivo. DBA and its metabolites, trans-DBA-1,2-dihydrodiol (DBA-1,2-DHD) trans-DBA-3,4-dihydrodiol (DBA-3,4-DHD) and trans-DBA-5,6-dihydrodiol (DBA-5,6-DHD), were topically applied on mice. DNA was isolated using enzyme-solvent extraction methods, and analyzed for carcinogen-DNA adducts using 32P-postlabelling. In skin, DBA produced two distinct adducts (Adducts 1 and 2). The same two adducts were seen when DBA-3,4-DHD was applied. In addition, the total adduct level elicited by DBA-3,4-DHD was twice that of the parent compound. Two adducts (Adducts 3 and 4) were also seen in mouse skin when DBA-5,6-DHD was applied, but these differed chromatographically from adducts seen with DBA. However, when DBA-3,4-DHD was applied and analyzed using sensitive nuclease P1 32P-postlabelling, all four adducts could be detected. These results suggest that the major route of DBA activation to DNA-binding species in skin is through formation of DBA-3,4-DHD and subsequent metabolism of this compound to a bay-region diol-epoxide. However, we postulate that another activation pathway may proceed through a bis-dihydrodiol-epoxide.

  4. A Brief Review of the Application of 14C in Terrestrial Carbon Cycle Studies

    Energy Technology Data Exchange (ETDEWEB)

    Guilderson, T; Mcfarlane, K

    2009-10-22

    An over-arching goal of the DOE TCP program is to understand the mechanistic controls over the fate, transport, and residence time of carbon in the terrestrial biosphere. Many of the modern process and modeling studies focus on seasonal to interannual variability. However, much of the carbon on the landscape and in soils is in separate reservoirs with turnover times that are multi-decadal to millennial. It is the controls on these longer term pools or reservoirs that is a critical unknown in the face of rising GHGs and climate change and uncertainties of the terrestrial biosphere as a future global sink or source of atmospheric CO{sub 2} [eg., Friedlingstein et al., 2006; Govindasamy et al., 2005; Thompson et al., 2004]. Radiocarbon measurements, in combination with other data, can provide insight into, and constraints on, terrestrial carbon cycling. Radiocarbon (t{sub 1/2} 5730yrs) is produced naturally in the stratosphere when secondary neutrons generated by cosmic rays collide with {sup 14}N atoms [Libby 1946; Arnold and Libby, 1949]. Upon formation, {sup 14}C is rapidly oxidized to CO and then to CO{sub 2}, and is incorporated into the carbon cycle. Due to anthropogenic activities, the amount of {sup 14}C in the atmosphere doubled in the mid/late 1950s and early 1960s from its preindustrial value of {sup 14}C/{sup 12}C ratio of 1.18 x 10{sup -12} [eg., Nydal and Lovseth, 1983]. Following the atmospheric weapons test ban in 1963, the {sup 14}C/{sup 12}C ratio, has decreased due to the net isotopic exchange between the ocean and terrestrial biosphere [eg., Levin and Hessheimer, 2000] and a dilution effect due to the burning of {sup 14}C-free fossil fuel carbon, the 'Suess Effect' [Suess, 1955]. In the carbon cycle literature, radiocarbon measurements are generally reported as {Delta}{sup 14}C, which includes a correction for mass dependent fractionation [Stuiver and Polach, 1977]. In the context of carbon cycle studies radiocarbon measurements can be

  5. Detection of nonauthorized genetically modified organisms using differential quantitative polymerase chain reaction: application to 35S in maize.

    Science.gov (United States)

    Cankar, Katarina; Chauvensy-Ancel, Valérie; Fortabat, Marie-Noelle; Gruden, Kristina; Kobilinsky, André; Zel, Jana; Bertheau, Yves

    2008-05-15

    Detection of nonauthorized genetically modified organisms (GMOs) has always presented an analytical challenge because the complete sequence data needed to detect them are generally unavailable although sequence similarity to known GMOs can be expected. A new approach, differential quantitative polymerase chain reaction (PCR), for detection of nonauthorized GMOs is presented here. This method is based on the presence of several common elements (e.g., promoter, genes of interest) in different GMOs. A statistical model was developed to study the difference between the number of molecules of such a common sequence and the number of molecules identifying the approved GMO (as determined by border-fragment-based PCR) and the donor organism of the common sequence. When this difference differs statistically from zero, the presence of a nonauthorized GMO can be inferred. The interest and scope of such an approach were tested on a case study of different proportions of genetically modified maize events, with the P35S promoter as the Cauliflower Mosaic Virus common sequence. The presence of a nonauthorized GMO was successfully detected in the mixtures analyzed and in the presence of (donor organism of P35S promoter). This method could be easily transposed to other common GMO sequences and other species and is applicable to other detection areas such as microbiology.

  6. Preliminary study on preparation, release velocity and intracorporeal physical distribution of 32P-chromic phosphate-poly (L-lactide) delayed release panicles

    International Nuclear Information System (INIS)

    Objective: The aim of this study was to prepare the 32P-chromic phosphate-poly(L-lac-tide) (32P-CP-PLLA) particles with different ratio of the materials and further examine their performance in-dex in vivo and in vitro and their intracorporeal distribution. Methods: The erosion, degrading rates, delayed release velocity and radioactivity self-absorption coefficient (RSAC) of 32P-CP-PLLA particles made from different materials were investigated and compared. After the implantation of 32P-CP-PLLA particles and the injection of 32P-CP colloids in the muscular tissues, the weight loss rate and the radioactivity release rate (RRR) of the particles were calculated. The intracorporeal distribution, radioactive half-life and bio-logical effect of 32P in the targeting sites were further studied. Statistical analysis was performed with SPSS 12.0, and one-way analysis of variance and t-test were used. Results: 32P-CP-PLLA particles were of green cylinder, with regular shape and radionuclide distribution. The RSAC of the particles was of little relation with molecular weight of PLLA and proportional to the ratio of PLLA to CP. The extracorporeal release rate increased with the reduction of molecular weight of PLLA and with the increase of the ratio of PLLA to CP. The RRR reached peak when PLLA was 3 times of CP. The 32P-CP, released with the degradation and corrosion of the particle distributed mainly in the surrounding muscles of the particle. And the peak of percentage activity of injection dose per gram of tissue (% ID/g) in liver, spleen and bone were 1. 7887, 1. 6401 and 1. 9470 respectively, much lower than that in the 32P-CP group (4.7523, 3.9712 and 4.3174 ; all t > 2.7, all P 32P-CP-PLLA, which can increase the targeting radioactive dosage and effective half-life in the implanting sites, can be served as an potential implanting agent for onco-therapy with a better perspective. (authors)

  7. Human systemic exposure to [14C]-paraphenylenediamine-containing oxidative hair dyes: Absorption, kinetics, metabolism, excretion and safety assessment

    NARCIS (Netherlands)

    Nohynek, G.J.; Skare, J.A.; Meuling, W.J.A.; Wehmeyer, K.R.; Bie, A.T.H.J. de; Vaes, W.H.J.; Dufour, E.K.; Fautz, R.; Steiling, W.; Bramante, M.; Toutain, H.

    2015-01-01

    Systemic exposure was measured in humans after hair dyeing with oxidative hair dyes containing 2.0% (A) or 1.0% (B) [14C]-p-phenylenediamine (PPD). Hair was dyed, rinsed, dried, clipped and shaved; blood and urine samples were collected for 48 hours after application. [14C] was measured in all mater

  8. New Observations of Regional Variability in Delta-14C of Background CO2 from the Scripps CO2 Program

    Science.gov (United States)

    Graven, H. D.; Guilderson, T. P.; Keeling, R. F.

    2007-12-01

    We present new records of Δ14C in CO2 from a set of 7 sites in the Scripps CO2 flask sampling program. The monthly records span 2 years at Palmer Station, 5 years at Mauna Loa, Kumukahi and Samoa, 7 years at Pt Barrow and South Pole, and 15 years at La Jolla. The long time series were made possible by the archiving of extracted CO2 samples. The samples were analyzed by Accelerator Mass Spectrometry (AMS) at the Lawrence Livermore National Laboratory, where an initiative to support high precision Δ14C analysis in CO2 with improved analytical methodology has been ongoing since 2003. The new records build on previous work by I. Levin, M. Manning, R. Nydal and others to characterize atmospheric Δ14C levels following nuclear weapons testing. Our time series reveal changes in the latitudinal profile of Δ14C that reflect shifting regional 14C fluxes. As 14C fluxes depend on the source of CO2 to the atmosphere, atmospheric 14C measurements improve our understanding of regional oceanic, biospheric and industrial CO2 exchanges and provide important constraints on carbon cycle models. The new records will additionally serve as a background definition for studies utilizing Δ14C measurements to identify local fossil fuel-derived CO2.

  9. Operation of the Harwell UK 14C Data Base and its Expansion through Data Exchange with Other Laboratories

    NARCIS (Netherlands)

    Walker, A.J.; Otlet, R.L.; Housley, R.A.; Plicht, Johannes van der

    1990-01-01

    The use of computer data bases for storage and retrieval of 14C data is a logical application for the rapidly expanding numbers of 14C determinations. Harwell has established a data base for all samples originating from sites in the United Kingdom and Eire. The core of the data is the Council for Br

  10. Transport mechanisms of trans-1-amino-3-fluoro[1-14C]cyclobutanecarboxylic acid in prostate cancer cells

    International Nuclear Information System (INIS)

    Introduction: We investigated the mechanisms of trans-1-amino-3-fluoro[1-14C]cyclobutanecarboxylic acid (anti-[14C]FACBC) transport by human-derived prostate cancer (PCa) cells and normal human prostatic epithelial cells (PrECs). Methods: Using PCa cells (DU145, PC-3, LNCaP) and PrECs, we performed the following in vitro experiments: time-course, kinetics, competitive inhibition by synthetic/naturally occurring amino acids (AAs), exchange transport with synthetic/naturally occurring AAs and pH-dependency of anti-[14C]FACBC uptake. We also examined the amino acid transporter (AAT) expression using flow cytometry. Results: The uptake of anti-[14C]FACBC by LNCaP and DU145 cells was higher than that by PC-3 and PrECs. The Km values for anti-[14C]FACBC were 64.4 and 191.7 μmol/L in the DU145 cells and PrECs, respectively. Total levels of anti-[14C]FACBC uptake were positively correlated with the expression level of system ASC in PCa cells. The contributions of Na+-dependent AATs to anti-[14C]FACBC uptake were greater than those of Na+-independent AATs, especially in PCa cells. In the presence of Na+, glutamine and serine showed the strongest inhibitory effect against anti-[14C]FACBC uptake, suggesting that system ASC, especially ASCT2, is an important AAT for anti-[14C]FACBC. In contrast, phenylalanine and 2-amino-bicyclo[2,2,1]heptane-2-carboxylic acid, but not N-ethylmaleimide, almost completely inhibited the anti-[14C]FACBC uptake in the absence of Na+, indicating the contribution of LAT1. In the exchange transport experiments, glutamine showed the strongest transstimulation of intracellular anti-[14C]FACBC efflux in DU145 cells. Furthermore, the contributions of Na+-independent AATs to the uptake of anti-[14C]FACBC in DU145 and PrECs were greater under acidic pH conditions than under neutral or alkaline pH conditions. Conclusions: Total uptake of anti-[14C]FACBC by PCa cells correlates with the expression level of system ASC in PCa cells. Furthermore, LAT1 is an

  11. Investigation of the association between glaucoma and Helicobacter pylori infection using the {sup 14}C-urea breath test

    Energy Technology Data Exchange (ETDEWEB)

    Tuzcu, Esra Ayhan; Aydogan, Fusun; Motor, Vicdan Koksaldi; Ilhan, Ozgur; Daglioglu, Mutlu Cihan; Coskun, Mesut; Parlakfikirer, Nihan; Keskin, Ugurcan, E-mail: drayhant@hotmail.com [Medical Faculty, Mustafa Kemal University, Hatay (Turkey)

    2015-07-01

    Purpose: to investigate the association between glaucoma and Helicobacter pylori infection by evaluating for the presence of H. pylori infection in patients with glaucoma using the 14C-urea breath test (14C-UBT). Methods: Using 14C-UBT, H. pylori infection positivity was compared between a group of patients with primary open-angle glaucoma and a control group with normal intraocular pressure and a normal optic disc or normal perimetry. Results: the 14C-UBT was positive in 18 (51.42%) out of 35 patients in the glaucoma group and in 15 (42.85%) out of 35 patients in the control group. H. pylori infection positivity rates were similar between the glaucoma and control groups (p>0.05). Conclusion: according to the 14C-UBT, there is no association between primary open-angle glaucoma and H. pylori infection. (author)

  12. Investigation of the association between glaucoma and Helicobacter pylori infection using the 14C-urea breath test

    International Nuclear Information System (INIS)

    Purpose: to investigate the association between glaucoma and Helicobacter pylori infection by evaluating for the presence of H. pylori infection in patients with glaucoma using the 14C-urea breath test (14C-UBT). Methods: Using 14C-UBT, H. pylori infection positivity was compared between a group of patients with primary open-angle glaucoma and a control group with normal intraocular pressure and a normal optic disc or normal perimetry. Results: the 14C-UBT was positive in 18 (51.42%) out of 35 patients in the glaucoma group and in 15 (42.85%) out of 35 patients in the control group. H. pylori infection positivity rates were similar between the glaucoma and control groups (p>0.05). Conclusion: according to the 14C-UBT, there is no association between primary open-angle glaucoma and H. pylori infection. (author)

  13. Syntheses of [sup 14]C-ochratoxin A and [sup 14]C-ochratoxin B and a comparative study of their distribution in rats using whole body autoradiography

    Energy Technology Data Exchange (ETDEWEB)

    Breitholtz-Emanuelsson, A.; Hult, K. (Department of Biochemistry and Biotechnology, Royal Institute of Technology, Stockholm (Sweden)); Fuchs, R. (Department of Toxicology, Institute for Medical Research and Occupational Health, University of Zagreb, Zagreb (Yugoslavia)); Appelgren, L.-E. (Department of Pharmacology and Toxicology, Faculty of Veterinary Medicine, Swedish University of Agricultural Sciences, Uppsala (Sweden))

    1992-01-01

    Methods for preparation of labelled ochratoxin A and B are described. The method for preparation of labelled ochratoxin B involves the synthesis of the azide of ochratoxin [beta] via the mixed anhydride and subsequent conjugation to labelled phenylalanine to yield [sup 14]C-ochratoxin B. The labelled ochratoxins were injected into male Wistar rats and after different survival times they were sacrificed and subjected to whole body autoradiography. The distribution pattern of ochratoxin A in the rat did not differ from that earlier registered for mouse. The previously known, high susceptibility of rats (and not mice) to ochratoxin A-induced cancer could thus not be explained by an accumulation of the toxin in specific cells or organs. The distribution patterns of ochratoxin A and B were almost congruent - the only apparent difference being a much longer retention of the labelled ochratoxin A in the blood compared to ochratoxin B, which was much faster excreted. When analyzing tissue extract for labelled metabolites only the extracts from the rats injected with ochratoxin B were found to contain easily detectable concentrations, while no metabolites of ochratoxin A were seen. (au).

  14. A comparison of U/Th and rapid-screen 14C dates from Line Island fossil corals

    Science.gov (United States)

    Grothe, Pamela R.; Cobb, Kim M.; Bush, Shari L.; Cheng, Hai; Santos, Guaciara M.; Southon, John R.; Lawrence Edwards, R.; Deocampo, Daniel M.; Sayani, Hussein R.

    2016-03-01

    Time-consuming and expensive radiometric dating techniques limit the number of dates available to construct absolute chronologies for high-resolution paleoclimate reconstructions. A recently developed rapid-screen 14C dating technique reduces sample preparation time and per sample costs by 90%, but its accuracy has not yet been tested on shallow-water corals. In this study, we test the rapid-screen 14C dating technique on shallow-water corals by comparing 44 rapid-screen 14C dates to both high-precision 14C dates and U/Th dates from mid- to late-Holocene fossil corals collected from the central tropical Pacific (2-4°N, 157-160°W). Our results show that 42 rapid-screen 14C and U/Th dates agree within uncertainties, confirming closed-system behavior and ensuring chronological accuracy. However, two samples that grew ˜6500 years ago have calibrated 14C ages ˜1000 years younger than the corresponding U/Th ages, consistent with diagenetic alteration as indicated by the presence of 15-23% calcite. Mass balance calculations confirm that the observed dating discrepancies are consistent with 14C addition and U removal, both of which occur during diagenetic calcite recrystallization. Under the assumption that aragonite-to-calcite replacement is linear through time, we estimate the samples' true ages using the measured 14C and U/Th dates and percent calcite values. Results illustrate that the rapid-screen 14C dates of Holocene-aged fossil corals are accurate for samples with less than 2% calcite. Application of this rapid-screen 14C method to the fossil coral rubble fields from Kiritimati Island reveal significant chronological clustering of fossil coral across the landscape, with older ages farther from the water's edge.

  15. Over-estimation of glucose-6-phosphatase activity in brain in vivo. Apparent difference in rates of [2-3H]glucose and [U-14C]glucose utilization is due to contamination of precursor pool with 14C-labeled products and incomplete recovery of 14C-labeled metabolites

    International Nuclear Information System (INIS)

    Significant dephosphorylation of glucose 6-phosphate due to glucose-6-phosphatase activity in rat brain in vivo was recently reported. The evidence was an apparent more rapid 3H than 14C loss from the glucose pool and faster [2-3H]glucose than [U-14C]glucose utilization following pulse labeling of the brain with [2-3H,U-14C]glucose. Radiochemical purity of the glucose and quantitative recovery of the labeled products of glucose metabolism isolated from the brain were obviously essential requirements of their study, but no evidence for purity and recovery was provided. When we repeated these experiments with the described isolation procedures, we replicated the results, but found that: 1) the precursor glucose pool contained detritiated, 14C-labeled contaminants arising from glucose metabolism, particularly 2-pyrrolidone-5-carboxylic acid derived from [14C]glutamine; 2) [14C]glucose metabolite were not quantitatively recovered; 3) the procedure used to isolate the glucose itself produced detritiated, 14C-labeled derivatives of [2-3H,U-14C]glucose. These deficiencies in the isolation procedures could fully account for the observations that were interpreted as evidence of significant glucose 6-phosphate dephosphorylation by glucose-6-phosphatase activity. When glucose was isolated by more rigorous procedures and its purity verified in the present studies, no evidence for such activity in rat brain was found

  16. Source apportionment of carbonaceous aerosol in Sao Paulo using 13C and 14C measurements

    Science.gov (United States)

    Oyama, Beatriz; Andrade, Maria de Fatima; Holzinger, Rupert; Röckmann, Thomas; Meijer, Harro A. J.; Dusek, Ulrike

    2016-04-01

    The Metropolitan Area of Sao Paulo is affected by high aerosol concentrations, which contain a large fraction of organic material. Up to date, not much is known about the composition and origin of the organic aerosol in this city. We present the first source apportionment of the carbonaceous aerosol fraction in Sao Paulo, using stable (13C) and radioactive carbon isotopes (14C). 14C provides a clear-cut distinction between fossil sources, which contain no 14C, and contemporary sources such as biofuels, biomass burning, or biogenic sources, which contain a typical contemporary 14C/12C ratio. 13C can be used to distinguish C3 plants, such as maize and sugarcane, from C4 plants. This can help to identify a possible impact of sugarcane field burning in the rural areas of Sao Paulo State on the aerosol carbon in the city. In the first part of the study, we compare two tunnel studies: Tunnel 1 is frequented only by light duty vehicles, which run mainly on mixtures of gasoline with ethanol (gasohol, 25% ethanol and 85% gasoline) or hydrated ethanol (5% water and 95% ethanol). Tunnel 2 contains a significant fraction of heavy-duty diesel vehicles, and therefore the fraction of biofuels in the average fleet is lower. Comparison of 14C in organic and elemental carbon (OC and EC) shows that in both tunnels there is no significant contribution of biofuels to EC. Combusting ethanol-gasoline fuels in a vehicle engine does apparently not result in significant EC formation from ethanol. Biofuels contribute around 45% to OC in Tunnel 1 an only 20% in Tunnel 2, reflecting a strong impact of diesel vehicles in Tunnel 2. In the second part of the study we conduct a source apportionment of ambient aerosol carbon collected in a field study during winter (July-August) 2012. Ambient EC has two main sources, vehicular emissions and biomass burning. We estimate a contribution of vehicular sources to EC of roughly 90% during weekdays and 80% during weekends, using the 14C values measured in

  17. Uptake of [14C]deoxyglucose into brain of young rats with inherited hydrocephalus

    International Nuclear Information System (INIS)

    The effect of hydrocephalus on cerebral glucose utilization as reflected by deoxyglucose uptake has been examined in rats with inherited hydrocephalus at 10, 20, and 28 days after birth using a semiquantitative method. Injection of [14C]deoxyglucose intraperitoneally was followed by freezing the brain, sectioning, and quantitative autoradiography of 10 brain regions. Brain [14C] concentration, cortical thickness, and plasma glucose concentrations were measured. Maximal thinning of the cerebral cortex had already occurred by 10 days after birth, although obvious symptoms such as gait disturbance developed after 20 days. In control rats, the cerebral isotope concentration was lower and more homogeneous at 10 days than at 20 or 28 days, which may be a reflection of the use of metabolic substrates other than glucose in younger animals. In order to make comparisons between control and hydrocephalic groups, tissue isotope concentrations were normalized to cerebellar cortex which was not affected by the hydrocephalus at any age. In hydrocephalic rats at 10 and 20 days, the concentration of [14C] was lower in all areas except the inferior colliculi and pons but the reduction was only significant in the sensory-motor cortex at 10 days and in the caudate nuclei at 20 days. By 28 days after birth, all areas except the cerebellum (six cortical regions, inferior colliculi, pons, and caudate) had significantly lower isotope concentrations in the hydrocephalic group. It is concluded that cerebral glucose metabolism is significantly reduced by 28 days after birth in H-Tx rats with congenital hydrocephalus and that less marked reductions occur prior to 28 days

  18. Longevity and growth of Acacia tortilis; insights from 14C content and anatomy of wood

    Directory of Open Access Journals (Sweden)

    Krzywinski Knut

    2007-06-01

    Full Text Available Abstract Background Acacia tortilis is a keystone species across arid ecosystems in Africa and the Middle East. Yet, its life-history, longevity and growth are poorly known, and consequently ongoing changes in tree populations cannot be managed in an appropriate manner. In other arid areas parenchymatic bands marking growth zones in the wood have made dendrochronological studies possible. The possibilities for using pre- and post-bomb 14C content in wood samples along with the presence of narrow marginal parenchymatic bands in the wood is therefore tested to gain further insight into the age, growth and growth conditions of A. tortilis in the hyper-arid Eastern Desert of Egypt. Results Based on age scenarios and the Gompertz growth equation, the age of trees studied seems to be from 200 up to 650 years. Annual radial growth estimated from calibrated dates based on the post-bomb 14C content of samples is up to 2.4 mm, but varies both spatially and temporally. Parenchymatic bands are not formed regularly. The correlation in band pattern among trees is poor, both among and within sites. Conclusion The post-bomb 14C content of A. tortilis wood gives valuable information on tree growth and is required to assess the age scenario approach applied here. This approach indicates high longevities and slow growth of trees. Special management measures should therefore be taken at sites where the trend in tree population size is negative. The possibilities for dendrochronological studies based on A. tortilis from the Eastern Desert are poor. However, marginal parenchymatic bands can give insight into fine scale variation in growth conditions and the past management of trees.

  19. Distribution and elimination of 4-/sup 14/C-mofebutazone in the rat

    Energy Technology Data Exchange (ETDEWEB)

    Graul, E.H.; Loew, D.; Schuster, O.

    1986-08-01

    Orally administered /sup 14/C mofebutazone is absorbed quickly and within 24 hours almost completely excreated - 80.5% in urine and 1.2% in the feces. Similar results have also been reported by BASS et al. Distribution results mainly over the organs of metabolisation and elimination. Apart from the gastrointestinal tract very high concentrations were found in the liver and kidneys after 45 minutes, but these concentrations diminished very distinctly after 6 hours and after 24 hours radioactivity was only detectable in the feces of the large intestine. /sup 14/C mofebutazone cannot be detected in lipophilic tissues such as fatty tissues, brain and spinal marrow at any of the points of time investigated. The bone marrow is also free of radioactivity to a great extent. However, under the skin and in the muscular tissue there is distinct radioactivity of /sup 14/C mofebutazone. On the other hand BRUNE was able to show that phenylbutazone was detectable in the bone marrow as well as in the organs of metabolisation and elimination. Further differences between mofebutazone and phenylbutazone should be shown by means of these investigations. Therefore, global statements and conclusions on the effect, mechanisms of effect and side effects of substances from a category of chemical substances are not justified in the case of non-steroidal antirheumatics. Slight chemical modifications often lead to other effects and side effects. With mofebutazone as an example it is shown that in spite of chemical similarity to phenylbutazone both substances are distinctly different with regard to toxicological, pharmacological, pharmacokinetic and chemical-physical aspects.

  20. Transformation of {sup 14}C-pyrimidynyloxybenzoic herbicide ZJ0273 in aerobic soils

    Energy Technology Data Exchange (ETDEWEB)

    Haiyan, Wang; Zhiyang, Yu; Ling, Yue; Ailiang, Han; Yanfei, Zhang; Juying, Li [Institute of Nuclear Agricultural Sciences, Key Laboratory of Nuclear Agricultural Sciences of Ministry of Agriculture, Zhejiang University, Hangzhou 310029 (China); Qingfu, Ye, E-mail: qfye@zju.edu.cn [Institute of Nuclear Agricultural Sciences, Key Laboratory of Nuclear Agricultural Sciences of Ministry of Agriculture, Zhejiang University, Hangzhou 310029 (China); Zhengmin, Yang [Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, Shanghai 200032 (China); Long, Lu, E-mail: lulong@mail.sioc.ac.cn [Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, Shanghai 200032 (China)

    2010-04-15

    A soil metabolism study of propyl 4-(2-(4,6-dimethoxypyrimidin-2-yloxy)benzylamino)benzoate (ZJ0273), a novel broad-spectrum herbicide, was carried out using {sup 14}C labeled on two different rings, i.e., [pyrimidine-4,6-{sup 14}C] ZJ0273 and [benzyl-U-{sup 14}C] ZJ0273. Ultralow liquid scintillation counting and LC-MS/MS were used to identify the degradation intermediates and quantify their dynamics in aerobic soils. Four aromatic intermediates, 4-(2-(4,6-dimethoxypyrimidin-2-yloxy)benzylamino)benzoic acid (M1), 4-(2-(4,6-dimethoxypyrimidin-2-yloxy)benzamido)benzoic acid (M2), 2-(4,6-dimethoxypyrimidin-2-yloxy)benzoic acid (M3), and 4,6-dimethoxypyrimidin-2-ol (M4), were identified and their identity was further confirmed against authentic standards. Analysis of metabolites suggested two degradation pathways: (1) Upon loss of the propyl group, M1 was produced via hydrolysis of propyl 4-(2-(4,6-dimethoxypyrimidin-2-yloxy)benzylamino)benzoate after which the C-N bond between rings A and B was cleaved by oxidation and biochemical degradation to yield M3, which was further converted into M4 and finally mineralized to CO{sub 2}; and (2) the first step was the same as in pathway 1, but M1 first underwent a carbonylation to form M2. The C-N bond between rings A and B of M2 was cleaved by hydrolysis to yield M3. Dynamic changes in the four metabolites in aerobic soils were also investigated by HPLC coupled analysis of radioactivity of isolated peaks. After a 100-day incubation, 1.7-9.7% of applied {sup 14}C was found as M1, 0.3-1.1% as M2, 14.5-20.9% as M3, and 3.7-6.7% as M4 in the soils, and pH appeared to be the most influential soil property affecting the formation and dissipation of these metabolites.

  1. Metabolic labeling with (14C)-glucose of bloodstream and cell culture trypanosoma cruzi trypomastigotes:

    International Nuclear Information System (INIS)

    Trypomastigote forms of Trypanosoma cruzi from infected mouse blood and from cell culture were metabolically labeled by incubation with D-(14C)-glucose. Analysis by polyacrylamide gel electrophoresis of lysates from parasites of two strains (RA and CA1) showed a significantly different pattern. The difference was mainly quantitative when the blood and cell culture trypomastigotes of the RA strain were compared. Analysis of the culture medium by paper electrophoresis showed an anionic exometabolite only in the blood forms of both strains. (Author)

  2. Dating Danish textiles and skins from bog finds by means of 14C AMS

    DEFF Research Database (Denmark)

    Mannering, Ulla; Possnert, Göran; Heinemeier, Jan;

    2010-01-01

    This paper presents the results of 44 new 14C analyses of Danish Early Iron Age textiles and skins. Of 52 Danish bog finds containing skin and textile items, 30 are associated with bog bodies. Until now, only 18 of these have been dated. In this paper we add dates to the remaining finds....... The results demonstrate that the Danish custom of depositing clothed bodies in a bog is centred to the centuries immediately before and at the beginning of the Common Era. Most of these bodies are carefully placed in the bog - wrapped or dressed in various textile and/or skin garments....

  3. Transformation of 14C-pyrimidynyloxybenzoic herbicide ZJ0273 in aerobic soils

    International Nuclear Information System (INIS)

    A soil metabolism study of propyl 4-(2-(4,6-dimethoxypyrimidin-2-yloxy)benzylamino)benzoate (ZJ0273), a novel broad-spectrum herbicide, was carried out using 14C labeled on two different rings, i.e., [pyrimidine-4,6-14C] ZJ0273 and [benzyl-U-14C] ZJ0273. Ultralow liquid scintillation counting and LC-MS/MS were used to identify the degradation intermediates and quantify their dynamics in aerobic soils. Four aromatic intermediates, 4-(2-(4,6-dimethoxypyrimidin-2-yloxy)benzylamino)benzoic acid (M1), 4-(2-(4,6-dimethoxypyrimidin-2-yloxy)benzamido)benzoic acid (M2), 2-(4,6-dimethoxypyrimidin-2-yloxy)benzoic acid (M3), and 4,6-dimethoxypyrimidin-2-ol (M4), were identified and their identity was further confirmed against authentic standards. Analysis of metabolites suggested two degradation pathways: (1) Upon loss of the propyl group, M1 was produced via hydrolysis of propyl 4-(2-(4,6-dimethoxypyrimidin-2-yloxy)benzylamino)benzoate after which the C-N bond between rings A and B was cleaved by oxidation and biochemical degradation to yield M3, which was further converted into M4 and finally mineralized to CO2; and (2) the first step was the same as in pathway 1, but M1 first underwent a carbonylation to form M2. The C-N bond between rings A and B of M2 was cleaved by hydrolysis to yield M3. Dynamic changes in the four metabolites in aerobic soils were also investigated by HPLC coupled analysis of radioactivity of isolated peaks. After a 100-day incubation, 1.7-9.7% of applied 14C was found as M1, 0.3-1.1% as M2, 14.5-20.9% as M3, and 3.7-6.7% as M4 in the soils, and pH appeared to be the most influential soil property affecting the formation and dissipation of these metabolites.

  4. Accelerated degradation of 14C-atrazine in an atrazine adapted field soil from Belgium

    Science.gov (United States)

    Hamacher, Georg; Jablonowski, Nicolai David; Martinazzo, Rosane; Accinelli, Cesare; Köppchen, Stephan; Langen, Ulrike; Linden, Andreas; Krause, Martina; Burauel, Peter

    2010-05-01

    Atrazine [2-chloro-4-(ethylamino)-6-(isopropylamino)-s-triazine] is one of the most widely used herbicides in the world. Atrazine is considered to be mobile in soil and has often been characterized as a rather recalcitrant compound in the environment. In the present study the accelerated atrazine degradation in an agriculturally used soil was examined. Soil samples were collected from a Belgian field which was used for corn-plantations and was regularly treated with atrazine during the last 30 years. The experiment was conducted under controlled laboratory conditions (GLP) using 14C-labelled and unlabelled atrazine in accordance to the reported field application dose of 1 mg kg-1. Triplicates of treated subsamples were incubated at 50% WHCmax and under slurry conditions (1:4 soil:solution ratio, using distilled water) in the dark at 20° C. Control samples were collected at an adjacent pear orchard where no atrazine or other triazine pesticides application was reported. After 92 days of incubation, the mineralized amount of atrazine reached 83% of the initially applied 14C-activity in the atrazine treated soil for the slurry setup. A maximum of atrazine mineralization was observed in the treated field soil between 6 and 7 days of incubation for both, 50% WHCmax and slurry setups. The total 14C-atrazine mineralization was equally high for 50% WHCmax in the atrazine treated soil. After an extended lag-phase in comparison to the treated soil the overall mineralization of 14C-atrazine of 81% was observed in the atrazine untreated soil under slurry conditions. This observation might be due to a possible cross adaption of the microflora. These results could be attributed to an atrazine drift during application since the control samples were taken in an adjacent pear orchard with no atrazine application history. These results demonstrate an adaption of the microflora to mineralize atrazine rapidly. The formation of desorbable metabolites as well as the formation of

  5. Efficiency of the refining process in removing 14C-diazinon residues in rape seed oil

    International Nuclear Information System (INIS)

    Rape seeds were treated with 14C-diazinon at 3.2 ppm, stored for 2 months and then subjected to extraction, alkali refining, bleaching and deodorization under laboratory conditions. The pesticide level in the oil was determined immediately after processing. Diazinon residues in oil decreased at each stage of processing and were reduced from 3.2 ppm in the crude oil to 2.4 in the refined oil; 93% of the residue was the parent insecticide. (author). 5 refs, 1 fig., 2 tabs

  6. Degradation of 14C-Carbaryl in soils modified by organic matter oxidation and glucose addition

    International Nuclear Information System (INIS)

    The behaviour of the insecticide carbaryl was studied during eight weeks by means of radiometric techniques in samples of Brunizem and Dark-Red Latosol soils from Parana, Brazil. Groups of oxidized, sterillized and untreated soils with and without glucose additions were incubated with 14C-Carbaryl and analyzed. In both soils, results showed and increase in the degradation rate of carbaryl on oxidized samples whereas adding glucose did not influence its degradation rate. Three metabolites having R sub(f) 0.23,0.40 and 0.70 were detected. (Author)

  7. Binding of mescaline with subcellular fractions upon incubation of brain cortex slices with [14C] mescaline.

    Science.gov (United States)

    Datta, R K; Antopol, W; Ghosh, J J

    1977-01-01

    Incubation of brain cortex slices in the presence of glucose resulted in the permeation of about 65% of [14C] mescaline into slices. Of this, about one-third radioactivity was bound with nuclei, mitochondria, microsomes, and ribosomes. Dialysis of subcellular fractions did not markedly reduce the amounts of radioactivity bound to the fractions. The permeation into slices and the binding of mescaline to subcellular fractions were fairly time-dependent, but were inhibited by the presence of potassium cyanide, or by the absence of glucose and by heating to 80 degrees C for 1 min.

  8. Fate of 14C-S-metolachlor in crop residues and underlying soils

    OpenAIRE

    Hatier, Jules

    2012-01-01

    S-metolachlor is a chlorocetanilide herbicide widely used as a pre-emergence and post-emergence weed control in a variety of crops such as maize (Zea mays L.), cotton (Gossypium hirsutum L.) and soybean (Glycine max L.). S-metolachlor and its metabolites are commonly found in surface and groundwater close to fields where this molecule is applied. This study aimed to evaluate the effect of crop residues on the interception, retention, degradation and mineralisation of 14C-S-metolachlor. One ba...

  9. Biodegradation of [(sup14)C]Benzo[a]pyrene Added in Crude Oil to Uncontaminated Soil

    OpenAIRE

    Kanaly, R.; Bartha, R.; Fogel, S; Findlay, M

    1997-01-01

    To investigate the possible cometabolic biodegradation of benzo[a]pyrene (BaP), crude oil spiked with [7-(sup14)C]BaP and unlabeled BaP was added to soil with no known pollution history, to give 34 g of oil and 67 mg of BaP/kg of dry soil. The oil-soil mixture was amended with mineral nutrients and incubated in an airtight container with continuous forced aeration. Total CO(inf2) and (sup14)CO(inf2) in the off-gas were trapped and quantified. Soil samples were Soxhlet extracted with dichlorom...

  10. Simultaneous electrochemical DNA hybridization assay for PAT and FMV 35S gene sequence using quantum dots as labels

    Institute of Scientific and Technical Information of China (English)

    Jiang Hua Zhong; Peng Qin; Wei Sun; Kui Jiao

    2008-01-01

    An electrochemical method for the simultaneous detection of two different DNA sequenees from PAT and FMV 35S gene sequence using CdS and PbS quantum dots (QDs)as labels was described.The QDs were readily functionalized with oligonucleotides as electrochemical DNA probes and selectively hybridized to the complementary sequences immobilized on the microplate.The QDs anchored on the hybrids were dissolved in the solution by the oxidation of HNO3 and further detected by a sensitive differential pulse anodic stripping voltammetric method(DPASV).The DPASV signals of the oxidation of Cd2+ and Pb2+ ions present in the solution were difierent and reflected the identity of corresponding ssDNA targets sequences.

  11. CNS depressants accelerate the dissociation of /sup 35/S-TBPS binding and GABA enhances their displacing potencies

    Energy Technology Data Exchange (ETDEWEB)

    Maksay, G.; Ticku, M.K.

    1988-01-01

    The specific binding of /sup 35/S-t-butylbicyclophosphorothionate (TBPS) was studied in synaptosomal membranes of rat cerebral cortex. The displacing potencies of eleven CNS depressants and three convulsants were determined in the presence of 1 /sup +/M GABA and 10 nM R 5135. GABA enhanced the displacing potencies of depressants of most diverse chemical structures: diaryltriazine (LY 81067), pyrazolopyridine (etazolate), cinnamide, glutarimide, 2,3-benzodiazepine (tofizopam) and alcohol derivatives, barbiturates, (+)etomidate, methaqualone and meprobamate. In contrast, the IC/sub 50/ values of convulsants (picrotoxinin, pentetrazol and the barbiturate enantiomer S(+)MPPB) were not significantly affected. The depressants accelerated either basal or GABA-augmented dissociation of /sup 35/-TBPS mainly by increasing the contribution of its rapid first phase.

  12. Improving phosphorus availability from Patos phosphate rock for Eucalyptus: a study with 32P radiotracer; Melhorando a disponibilidade de fosforo da rocha fosforica de Patos para eucalipto: um estudo com radiotracador 32P

    Energy Technology Data Exchange (ETDEWEB)

    Villanueva, Felipe Carlos Alvarez [Instituto de Investigaciones Fundamentales en Agriculturea Tropical (INIFAT), Santiago de las Vegas, La Habana (Cuba)]. E-mail: falvarez@cena.usp.br; Muraoka, Takashi; Trevizam, Anderson Ricardo [Centro de Energia Nuclear na Agricultura (CENA), Piracicaba, SP (Brazil). Lab. de Fertilidade do Solo; Franzini, Vinicius Ide [Sao Paulo Univ., Piracicaba, SP (Brazil). Escola Superior de Agricultura Luiz de Queiroz. Programa de Pos-graduacao em Solos e Nutricao de Plantas; Rocha, Alexandre Prado [Escola de Engenharia de Piracicaba, SP (Brazil)

    2006-01-15

    Eucalyptus plantation in Brazil is generally set on low fertility soils, therefore phosphorus (P) fertilization is mandatory and increases the cost of plantation operation. Using species that more efficiently uptake phosphorus from less soluble sources is an interesting option. However, little is known about eucalyptus regarding its ability of using less soluble forms of phosphorus. The use of P by eucalyptus (E. urophylla, E. grandis, and E. urophylla E. grandis) was studied in greenhouse using a loamy-textured, hipodystrophic Typic Haplustox from the Cerrado region, and 32P isotopic method. The P sources tested were triple superphosphate (TSP), phosphate rock (PR) and the triple superphosphate mixed with PR (TSP+PR). The effectiveness of P sources in terms of increasing dry matter yield was TSP = (TSP + PR) > PR, and the P uptake followed the order (TSP + PR) > TSP > PR for both species plus the hybrid. The increase in P uptake from PR due to TSP influence was 217.3% for E. urophylla, 235.7% for E. grandis, and 28.7% for E. urophylla E. grandis, indicating an enhancement effect of TSP on the effectiveness of PR. The hybrid E. urophylla E. grandis was the most efficient genotype on P soil use and E. grandis most exigent in P fertilizer. (author)

  13. Detection of GAD-Ab index in diabetic patients using 35S labeled recombinant human GAD65 antigen

    International Nuclear Information System (INIS)

    Objective: To establish a novel method for measuring glutamic acid decarboxylase autoanti-bodies(GAD-Ab). Methods: Recombinant human GAD65 was used as the antigen, in vitro transcribed and translated 35S-GAD65 as the tracer, a self-designed rotating incubation apparatus as the incubator, protein-A sepharose as the precipitator, and the liquid scintillation counter was used to measure radioactive count value to detect GAD-Ab. The positive cut-off point of GAD-Ab index was determined as > 0.05 by the 99.5% percentile in 109 healthy individuals. GAD-Ab levels were determined in 43 type 1 and 226 type 2 diabetic patients. Results: The optimized working conditions included SJ1515 35S-methionine for in vitro transcription and translation, 20-30 r/min setup of rotating incubation apparatus, test temperature 4-25 degree C, freshly prepared buffer of pH 7.2-7.4, and horizontal rotor centrifuge. The new method was better than original one, with intra-assay CV of 4.9%-8.3% and inter-assay CV of 7.1%-10.8 %, specificity of 98.2%. The results were comparable with the figures issued by an international standardized laboratory (concordance was 98.3%, Kappa value 0.971). The positive rate of GAD-Ab was 58.1% (25 of 43) in type 1 and 10.2%(23 of 226) in type 2 diabetes patients, but only 1.8% (2 of 109) in healthy individuals. Conclusion: The new assay for GAD-Ab is a highly sensitive, accurate, specific and reproducible method for clinical use

  14. Internal dosimetry for [4-{sup 14}C]-cholesterol in humans; Dosimetria interna para o [4-{sup 14}C]-colesterol em humanos

    Energy Technology Data Exchange (ETDEWEB)

    Marcato, Larissa Andreto

    2012-07-01

    The main objective of this work is to provide a biokinetic model in order to estimate the radiometric dose due to intake of [4-{sup 14}C]-cholesterol. The model was validated comparing the values of fecal excretion and absorption described in literature with that predicted by the model. The proposed model achieved good concordance between the results (p = 0.416 for excretion and p = 0.423 for absorption). The coefficients of effective dose (SvBq{sup -1}), equivalent dose (SvBq{sup -1}) and absorbed dose (GyBq{sup -1}) in human organs and tissues were calculated using the MIRD methodology and the compartmental analysis software ANACOMP. The coefficients were estimated for four phantoms: adult with a body mass of 73.3 kg, 15 years old adolescent (56.9 kg), 10 years old child (33.2 kg) and five years old child (19.8 kg). The organ that received the highest absorbed dose for all phantoms was the lower large intestine (LLI). The allometry theory was used to interpolate the coefficient of absorbed dose in the lower large intestine (DLLI) for unknown body mass (m): DLLI (GyBq{sup -1})=161.26 m (kg){sup -1.025}. For the same administered activity, the effective dose coefficient (E) decreases as the body mass increases. On other words, for the same intake activity, individuals with low body mass are exposed to higher doses. The allometry theory was used to interpolate the coefficient effective dose (E) for unknown body mass (m): E(SvB{sup -1})= 171.1 m(kg){sup -1,021}. (author)

  15. Direct measurement of stellar neutron capture rates of 14C and comparison with the Coulomb breakup method

    Science.gov (United States)

    Reifarth, Rene; Heil, M.; Plag, R.; Besserer, U.; Couture, A.; Dababneh, S.; Dörr, L.; Forssén, C.; Görres, J.; Haight, R. C.; Mengoni, A.; O'Brien, S.; Patronis, N.; Rundberg, R. S.; Uberseder, E.; Wiescher, M.; Wilhelmy, J. B.

    The neutron capture cross section of 14 C has been shown to be important for several neutron driven nucleosynthesis scenarios. Due to the high neutron abundance it is expected that the 14 C(n,γ) reaction competes strongly with other neutron-induced reactions on 14 C. The 14 C(n,γ) reaction is also important to validate (n,γ) cross sections obtained via the inverse reaction by the Coulomb breakup method. In principle, 14 C belongs to the few cases where this correspondence can be validated in a convincingly clean way. So far, the example of 14 C is obscured, however, by discrepancies between several experiments and theory. In this contribution we report on a re- analysis of the direct measurements of the 14 C(n,γ) reaction presented on the last NIC conference (Vancouver, 2004). The neutron energies used during the experiment ranged from 30 to 800 keV. The earlier presented disagreement between the direct measurements and the Coulomb breakup method has been resolved.

  16. Distribution of aged atrazine related 14C-residues in natural soil following incubation with the earthworm Apporectodea caliginosa

    Science.gov (United States)

    Andreou, Kostas; Semple, Kirk; Jones, Kevin

    2010-05-01

    The distribution and localisation of atrazine related 14C-residues into the different physical fractions of soil may reveal information on processes taking place in soil. Soils amended with 14C-atrazine, were aged for 22 years under environmental conditions in a lysimeter in Germany. The soil was sampled and subjected to physical and chemical fractionation before and after incubation for 7 days with the earthworm Apporectodea caliginosa. No significant change in the soil physical and chemical fractionation of the atrazine related 14C-residues and organic carbon was observed in this study due to the activity of the A. caliginosa. The smaller size soil fractions (Microaggregates and Colloids) were highly enriched with aged atrazine 14C-residues equivalents and organic carbon. Also the humic acid extracted using a simple alkaline extraction have were also enriched with aged atrazine 14C-residues equivalents. The low organic carbon content of the soil, the absence of relatively fresh organic matter and the long ageing time might explain the limited bioavailability of the atrazine related 14C-residues to the earthworm. This finding is of particular importance given that the soil used here was aged under natural environmental conditions compared to laboratory studies. Earthworms are important species in soil ecology and thus, the question of the bioavailability of aged pesticide residues to such organism is critical. The bioavalability of the atrazine 14C-residues equivalent was absent in the current study illustrating that those aged residues posed minimal risk to earthworms.

  17. Microdose 14C urea breath test for the diagnosis of Helicobacter pylori: a survey in Iranian population

    Directory of Open Access Journals (Sweden)

    Reza Dowlatabadi Bazaz

    2005-01-01

    Full Text Available The carbon -14 urea breath test (UBTis a non-invasive and simple method for the diagnosis of Helicobacter pylori infection. Attempts have been made to use lower doses of 14C-urea in the UBT in order to reduce the radiation risk of the test. The aim of this study was to assess the accuracy of a microdose (1 µCi [37 KBq] 14C-UBT in Iranian population for validation of its diagnostic accuracy against gold standard methods. Eighty and two patients were subjected to upper gastrointestinal endoscopy as well as 14C-UBT in one week. Rapid urease test and histological examinations were used as gold standard. Breath samples were collected 10, 20 and 30 minute after ingestion of 1 µCi of 14C- urea solution and their activities were measured using a scintillation counter and expressed as counts per minute (cpm and disintegration per minute (dpm. Good agreement was observed between the 14C-UBT and gold standard for samples which were collected 20 minutes after 14C-urea administration. The 14CUBT showed 100% sensitivity, 95% specificity, 95.45% positive predictive value, 100% negative predictive value and 97.50% accuracy. The results of this study showed good concordance between the 14C-UBT and invasive methods.

  18. Estimation of 14CO2 flux at soil-atmosphere interface and distribution of 14C in forest ecosystem

    International Nuclear Information System (INIS)

    To realize the dynamical behavior of 14C among exchangeable carbon reservoirs in terrestrial environment, a method for in situ determination of 14CO2 flux at soil-atmosphere interface and a high flow rate CO2 sampler were developed. This method allowed us to collect integrated quantity of CO2 for determining 14C activity over an extended time period under environmental conditions with minimal site disturbance. The 14CO2 flux from ground surface was estimated to be 1.59x10-5 Bq m-2 s-1 in a forest floor with the method. The specific activities of 14C in environmental materials such as some biological and air samples were also determined in the vicinity of the place, where the flux measurement was made, to discuss the behavior of 14C in the forest ecosystem. The results indicated that fresh pine needles had a similar 14C specific activity to the atmospheric CO2 at the same height due to its fairly rapid equilibrium, 14C specific activity in the atmospheric CO2 has a concentration gradient near the ground surface and, at least in this site, CO2 with high 14C specific activity was generated by decomposition of soil organic matter which may be accumulated in soil as a result of former nuclear weapons tests

  19. Analysis and Characterization of Organic Carbon in Early Holocene Wetland Paleosols using Ramped Pyrolysis 14C and Biomarkers

    Science.gov (United States)

    Vetter, L.; Schreiner, K. M.; Fernandez, A.; Rosenheim, B. E.; Tornqvist, T. E.

    2014-12-01

    Radiocarbon analyses are a key tool for quantifying the dynamics of carbon cycling and storage in both modern soils and Quaternary paleosols. Frequently, bulk 14C dates of paleosol organic carbon provide ages older than the time of soil burial, and 14C dates of geochemical fractions such as alkali and acid extracts (operationally defined as humic acids) can provide anomalously old ages when compared to coeval plant macrofossil dates. Ramped pyrolysis radiocarbon analysis of sedimentary organic material has been employed as a tool for investigating 14C age spectra in sediments with multiple organic carbon sources. Here we combine ramped pyrolysis 14C analysis and biomarker analysis (lignin-phenols and other cupric oxide products) to provide information on the source and diagenetic state of the paleosol organic carbon. We apply these techniques to immature early Holocene brackish wetland entisols from three sediment cores in southeastern Louisiana, along with overlying basal peats. Surprisingly, we find narrow 14C age spectra across all thermal aliquots from both paleosols and peats. The weighted bulk 14C ages from paleosols and overlying peats are within analytical error, and are comparable to independently analyzed 14C AMS dates from charcoal fragments and other plant macrofossils from each peat bed. Our results suggest high turnover rates of carbon in soils relative to input of exogenous carbon sources. These data raise broader questions about processes within the active soil and during pedogenesis and burial of paleosols that can effectively homogenize radiocarbon content in soils across the thermochemical spectrum. The concurrence of paleosol and peat 14C ages also suggests that, in the absence of peats with identifiable plant macrofossils, ramped pyrolysis 14C analyses of paleosols may be used to provide ages for sea-level indicators.

  20. Modeling of irradiated graphite (14)C transfer through engineered barriers of a generic geological repository in crystalline rocks.

    Science.gov (United States)

    Poskas, Povilas; Grigaliuniene, Dalia; Narkuniene, Asta; Kilda, Raimondas; Justinavicius, Darius

    2016-11-01

    There are two RBMK-1500 type graphite moderated reactors at the Ignalina nuclear power plant in Lithuania, and they are under decommissioning now. The graphite cannot be disposed of in a near surface repository, because of large amounts of (14)C. Therefore, disposal of the graphite in a geological repository is a reasonable solution. This study presents evaluation of the (14)C transfer by the groundwater pathway into the geosphere from the irradiated graphite in a generic geological repository in crystalline rocks and demonstration of the role of the different components of the engineered barrier system by performing local sensitivity analysis. The speciation of the released (14)C into organic and inorganic compounds as well as the most recent information on (14)C source term was taken into account. Two alternatives were considered in the analysis: disposal of graphite in containers with encapsulant and without it. It was evaluated that the maximal fractional flux of inorganic (14)C into the geosphere can vary from 10(-11)y(-1) (for non-encapsulated graphite) to 10(-12)y(-1) (for encapsulated graphite) while of organic (14)C it was about 10(-3)y(-1) of its inventory. Such difference demonstrates that investigations on the (14)C inventory and chemical form in which it is released are especially important. The parameter with the highest influence on the maximal flux into the geosphere for inorganic (14)C transfer was the sorption coefficient in the backfill and for organic (14)C transfer - the backfill hydraulic conductivity. PMID:27387810

  1. (14)C levels in the vicinity of the Fukushima Dai-ichi Nuclear Power Plant prior to the 2011 accident.

    Science.gov (United States)

    Xu, Sheng; Cook, Gordon T; Cresswell, Alan J; Dunbar, Elaine; Freeman, Stewart P H T; Hastie, Helen; Hou, Xiaolin; Jacobsson, Piotr; Naysmith, Philip; Sanderson, David C W; Tripney, Brian G; Yamaguchi, Katsuhiko

    2016-06-01

    A 50-year-old Japanese cedar (Cryptomeria japonica) from Okuma, ∼1 km southwest of the Fukushima Dai-ichi Nuclear Power Plant, was cored and each annual ring was analysed for (14)C. The (14)C specific activity values varied from 330.4 Bq kg(-1) C in the tree ring formed in 1971 to 231.2 Bq kg(-1) C in the 2014 ring. During the periods 1971-1976 and 2011-2014, the (14)C specific activities are indistinguishable from the ambient background values. However, compared with the ambient atmospheric levels, the (14)C specific activities between 1977 and 2010 are significantly elevated, clearly indicating (14)C discharges from the reactors during their normal operations. In addition, the specific activities are positively correlated with the annual electricity generation values. The excess (14)C specific activities were wind direction is east-southeast/southeast with a frequency of ∼30%, in comparison to ∼20% frequency for the direction of the site under study (north-northeast/northeast). This would tend to indicate a similar magnitude of additional effective dose and consequently no significant radiological impact of atmospheric (14)C discharges from the FDNPP during the entire period of normal operations. Additionally, no (14)C pulse in activity can be observed in the year 2011 ring. This might be caused by a limited (14)C release from the damaged reactors during the accident or that the prevailing wind during the short period of release (11th-25th March 2011) was not in the direction of Okuma.

  2. Distribution of sup 14 C mancozeb in a model vegetable (Brassica rapa) ecosystem

    International Nuclear Information System (INIS)

    Studies on the distribution of 14C-mancozeb in a model vegetable ecosystem were carried out. Spraying with mancozeb at one time (1X) (0.15 g active ingredient/m2) and at two times (2X) recommended doses (0.30 g active ingredient/m sup 2) was separately carried out on 30 day old Brassica rapa plants, and a second treatment was carried out a week later. Residues of 14C-mancozeb were determined using radio-nuclear technique. It was found that the level of mancozeb residues for the 2X recommended dose at zero time (ie: within 24 hours) after the first treatment were higher (3.51 and 1.04 mg/g); compared with the 1X recommended dose ( 0.61 and 0.12 mg/g) in leaf and stem, respectively. Seven days after the first spraying treatment, residue levels had dropped to 7.5% and 16.4% for leaf and stem (2X recommended dose) and 10.8% and 37.9%, respectively for (1X recommended dose). After the second spraying, the residue levels had increased for both doses in the leaf and stem but were not as high as day zero. Mancozeb levels determined for the 1x dose at 14 days after the second spraying were still relatively high in the leaf sample, suggesting that the present spraying protocol as recommended for fungicide is still not satisfactory

  3. Liming effect in the degradation of 14C-glyphosate in soils

    Energy Technology Data Exchange (ETDEWEB)

    Arantes, Sayonara A.C.M.; Lavorenti, Arquimedes [Universidade de Sao Paulo (USP), Piracicaba, SP (Brazil). Escola Superior de Agricultura Luiz de Queiroz]. E-mails: samoreno@esalq.usp.br; alavoren@esalq.usp.br; Tornisielo, Valdemar L. [Centro de Energia Nuclear na Agricultura (CENA), Piracicaba, SP (Brazil)]. E-mail: vltornis@cena.usp.br

    2007-07-01

    Liming is soil fertility management practice essential in tropical soils, in general extremely acidic. This practice, by influencing physical, chemical and biological features of soils may influence the behavior of organic molecules in soils. The glyphosate is one the most widely used pesticides in Brazil in several cultures to pest management control. Studies on its fate in soil are still incipient, mainly under the effect of liming practice The objective of the present study was to verify the effect of liming practice in the degradation of glyphosate in Red Latosol (LE) and Quartzarenic Neosol (RQ) soils and also in the microbial activity of the same soils. The experiment was conducted in a completely randomized design in a 2 x 2 factorial scheme, corresponding to two soils and two management conditions (with liming and without liming), with four replicates. The Radiometric technique was utilized to evaluate the evolution the {sup 14}CO{sub 2} at intervals of 7 days, during 70 days. The study of microbial activity was conducted parallel to the degradation experiment, using the methodology of radiolabelled glucose ({sup 14}C-glucose), which was measured at intervals of fourteen days, during 70 days. The results showed that in the studied soils, the liming increased the {sup 14}C-glyphosate mineralization and the microbial activity. (author)

  4. Assessment of the (14C) aminopyrine breath test in liver disease

    International Nuclear Information System (INIS)

    Different methods of performing the (14C) aminopyrine breath test have been assessed. A tracer dose of 2 μCi without a loading dose and with a single breath collection at two hours was the method selected, since it gave the best discrimination between patients with hepatocellular diseases and normal subjects (5.2 +- 0.2%, mean - SEM). Reduced values occurred in patients with chronic active hepatitis (with and without cirrhosis) (1.5 +- 0.2%), alcoholic cirrhosis (1.7 +- 0.4%) and hepatitis (2.5 +- 0.3%), and late primary biliary cirrhosis suggesting defective microsomal function with respect to demethylation. Normal results were common in early primary biliary cirrhosis. Two weeks of prednisolone therapy caused some improvement in the breath test in nine of ten patients with chronic active hepatitis. It is concluded that the (14C) aminopyrine breath test is a simple test for detecting hepatocellular dysfunction, but has no obvious diagnostic advantage over the determination of serum aspartate transaminase and two hour post-prandial bile-acids. (author)

  5. Liming effect in the degradation of 14C-glyphosate in soils

    International Nuclear Information System (INIS)

    Liming is soil fertility management practice essential in tropical soils, in general extremely acidic. This practice, by influencing physical, chemical and biological features of soils may influence the behavior of organic molecules in soils. The glyphosate is one the most widely used pesticides in Brazil in several cultures to pest management control. Studies on its fate in soil are still incipient, mainly under the effect of liming practice The objective of the present study was to verify the effect of liming practice in the degradation of glyphosate in Red Latosol (LE) and Quartzarenic Neosol (RQ) soils and also in the microbial activity of the same soils. The experiment was conducted in a completely randomized design in a 2 x 2 factorial scheme, corresponding to two soils and two management conditions (with liming and without liming), with four replicates. The Radiometric technique was utilized to evaluate the evolution the 14CO2 at intervals of 7 days, during 70 days. The study of microbial activity was conducted parallel to the degradation experiment, using the methodology of radiolabelled glucose (14C-glucose), which was measured at intervals of fourteen days, during 70 days. The results showed that in the studied soils, the liming increased the 14C-glyphosate mineralization and the microbial activity. (author)

  6. {sup 14}C dating beta decay with chiral effective field theory

    Energy Technology Data Exchange (ETDEWEB)

    Holt, Jeremy; Kaiser, Norbert; Weise, Wolfram [Technische Universitaet Muenchen, Muenchen (Germany)

    2009-07-01

    The anomalously long beta-decay lifetime of {sup 14}C, which is essential for the science of radiocarbon dating, has long been a challenge for nuclear structure theory. Here we present a shell model calculation of this decay, treating the initial and final nuclear states as two p-holes in an {sup 16}O core. Employing the low-momentum nucleon-nucleon (NN) interaction V{sub low-k} only, we find that the Gamow-Teller transition matrix element is too large to describe the known lifetime of {sup 14}C. As a novel approach to this problem, we invoke the chiral three-nucleon force (3NF) at leading order and derive from it a density-dependent in-medium NN interaction. After including these in-medium contributions, we find that the Gamow-Teller matrix element vanishes at a nuclear density close to that of saturated nuclear matter. The genuine short-range part of the 3NF is identified as the most important contribution leading to the observed suppression, and we find that although individual terms arising from the long- and medium-range parts of the chiral 3NF can be large, they significantly cancel.

  7. 14C-dimethoate residues in olive oil during oil processing

    International Nuclear Information System (INIS)

    An olive tree was treated twice with 14C-dimethoate (8.8 MBq/2.4g) and residues were determined in the olive fruits at harvest. The fruits were crushed and pressed to extract the crude oil, then refined by neutralization, bleaching and deodorization. The residue in crude oil was 1.66 mg/kg. Neutralization resulted in a significant reduction of residues to 0.89 mg/kg while bleaching and deodorization further reduced the residue to 0.67 mg/kg. Industrially extracted crude oil was fortified with 14C-dimethoate at 1.78 mg/kg level and refined in the same way. A sharp decrease by neutralization to 0.14 mg/kg was observed. The comparison strongly suggests that residues in aged and fortified samples are not entirely the same. This is to be anticipated, as the aged residue usually consists of parent and degradation products while the fortified residue is exclusively dimethoate. The terminal residue in the refined oil obtained from the field experiment did not contain dimethoate. (author). 7 refs, 3 figs, 3 tabs

  8. Efficiency of the refining processes in removing 14C-dichlorvos residues in soybean oil

    International Nuclear Information System (INIS)

    Crude soybean oil extracted from grains treated with 14C-dichlorvos at a dose 24 mg insecticide / kg seeds and stored for 30 weeks was subjected to different refining processes such as alkali treatment, bleaching, winterization and deodorization. The effect of the refining processes on the nature and magnitude of the originally present residues was investigated. The insecticide residues in crude oil and cake amounted to 9.5% and 55% , respectively, of original residues inside the seeds. Extraction of the seeds with hexane gave crude oil with 9.5 % of original residues in seeds. The l4C-activity in the crude stored Soya beans oil could be reduced by about 82% of radioactivity originally present in crude oil eliminated by simulated commercial processes locally used for oil refining. A high percentage of the residues (50-55%) were eliminated during alkali treatment and bleaching. Refining of soybeans oil fortified with '14C-dichlorovos. The final refined oil had only 13% of the radioactivity originally present, mainly in the form of dichlorvos, dimethyl and monomethyl phosphate in addition to desmethyl dichlorvos in oil with aged residues

  9. The 14C natural isotope as a tool for monitoring of groundwater exploitation

    International Nuclear Information System (INIS)

    The 14C natural isotope has been used to monitored exploitation effects within a 10 year interval between 1995 to 2005 in Bontang groundwater basing east Borneo- Indonesia. Exploitation of the groundwater of Bontang basin has occurred since 1981 and at the present the groundwater abstraction for Bontang basin is about 59,000 m3/day to fulfill the necessity of liquid natural gas and fertilizer industries from more than 20 wells. Isotope investigation of the groundwater Bontang basin have been done through water sources sampling like rivers, cold spring deep wells sea water and rain water in 1995 and 2005. The 18O and D isotope data show that deep groundwater originates from local rain water that infiltrates through the slope of mount Lobang Batik. Along the hilly slope zone, it is layered by the sedimentary Kampung Baru Formation. There is no indication that the Mahakam river water infiltrates and sea water intrusion to the deep groundwater. The 14C of isotope data from deep wells show that the average age of 4 wells with distance 2-3 km located from the outcrop of Kampung Baru in 1995 is about 2300 a. There is a decrease of groundwater age since exploitation to around 500 a. Decreasing of groundwater age is possible due to mixing with recent recharge through the Kampung Baru formation. (author)

  10. Highly Sensitive 14C and 3H Quantification of Biochemical Samples Using Accelerator Mass Spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Ognibene, T J; Vogel, J S

    2003-10-23

    Accelerator Mass Spectrometry (AMS) is an isotope ratio mass spectrometer that quantifies low levels of rare isotopes with half-lives between 10 and 10{sup 8} years. Typical sensitivities are 10{sup 6} atoms in a milligram-sized sample. AMS was originally developed for use in the geosciences as a tool to carbon date archaeological artifacts, but has applications in many fields. In the biosciences, the extreme sensitivity of AMS is used to trace nutrients, toxins and therapeutics in humans and animals using less than {micro}g/kg doses containing between 1-100 nCi of {sup 14}C. This sensitivity is used to reduce sample size, reduce chemical exposures to environmental or physiological levels, reduce radiation exposures to subjects, and/or reduce radioactive (and ''mixed'') waste. Compared to decay counting, AMS provides for a much higher measurement throughput for low activity samples. For example, a milligram-sized sample containing 1 dpm of {sup 14}C can be measured to 3% precision in several seconds. That same sample would require approximately 1 week of decay counting to obtain similar precision.

  11. The balance of distribution and conversion of pentachlorophenal 14C in rice plants and soil

    International Nuclear Information System (INIS)

    Rice plants were cultivated in a climatic chamber in vessels with 7-8 kg soil which was contaminated with 14C pentachlorophenol. The soil was flooded with water during the growth period. The test was carried out until the rice plants were ripe. All parts of the system (atmosphere, straw and ears, roots and stubble, infiltration water, soil and washing water from the roots) were then investigated for their 14C content. It could be seen that pentachlorophenol does not belong to the so-called 'persistant' environmental chemicals. After a period of vegetation, only about 1% of the initial substance is found in the plant/soil system. Besides the volatility of the initial substance and/or decomposition products into the atmosphere, a stepwise reductive dechlorination takes place in the soil and plants and finally the residues are bonded in a specific form to soil and plants. Residues can occur in the rice grains after soil treatment of rice cultures which also are largely bonded and cannot be chemically characterized. Its toxicological significance has not been thoroughly investigated. The question of the long-term consequences of the bonded residues still needs extensive research despite the favourable conclusion that can be drawn from this study on environmental behaviour of pentachlorophenol. (orig.)

  12. Study of the fate of 14C-lindane in laying hens

    International Nuclear Information System (INIS)

    The distribution and elimination of 14C-lindane (gamma-hexachlorocyclohexane) were studied in laying hens. 14C-lindane was administered orally at 0.78 μCi/5 μg per hen daily for 30 consecutive days. Animals were then sacrificed at determined time intervals. Radiocarbon was detected in the muscles, liver, fat, brain and ovary as well as in eggs and faeces. The highest radioactivity in tissues and organs was detected one day after the last dose was administered. Residues were particularly high in fat (0.164 μg/g). The radioactivity in the egg-yolk increased gradually reaching a peak on the 26th day (0.102 μg/g) and then began to decline slowly. After 90 days, radiocarbon was still detectable in the egg-yolk. A considerable amount of labelled lindane residues was eliminated via faeces. The studies conducted with radioactive lindane have shown that the application of nuclear techniques has provided a very sensitive, accurate and simple method for residue analysis. (author)

  13. Transmission of [14C]deoxynivalenol to eggs following oral administration to laying hens

    International Nuclear Information System (INIS)

    Following a single oral dose of [14C]deoxynivalenol (2.2 mg of DON, 2.4 μCi/bird) low levels of residues were transmitted to eggs. Maximum radioactivity, which occurred in the first eggs laid after dosing (within 24 h), amounted to 1.9 μg DON-equivalents/60-g egg (0.087% of dose) levels dropped rapidly in ensuing eggs. During daily consumption of DON, administered in spiked feed over a 12-day period (2.2 mg of DON/bird per day for 6 days followed by 2.2 mg of [14C]DON, 1.5 μCi/bird per day for 6 days), radioactivity levels increased with each subsequent egg laid up until the last exposure to the toxin; maximum levels accounted for 4.2 μg DON-equivalents/60-g egg. Residues quickly declined once the birds were switched to clean feed. Results indicate that although residues appear to accumulate in eggs, levels do not persist once the contaminated source is withdrawn. Preliminary analysis of egg material showed only about 10% of radioactivity present could be identified as the parent toxin, DON

  14. Threshold groundwater ages and young water fractions estimated from 3H, 3He, and 14C

    Science.gov (United States)

    Kirchner, James; Jasechko, Scott

    2016-04-01

    It is widely recognized that a water sample taken from a running stream is not described by a single age, but rather by a distribution of ages. It is less widely recognized that the same principle holds true for groundwaters, as indicated by the commonly observed discordances between model ages obtained from different tracers (e.g., 3H vs 14C) in the same sample. Water age distributions are often characterized by their mean residence times (MRT's). However, MRT estimates are highly uncertain because they depend on the shape of the assumed residence time distribution (in particular on the thickness of the long-time tail), which is difficult or impossible to constrain with data. Furthermore, because MRT's are typically nonlinear functions of age tracer concentrations, they are subject to aggregation bias. That is, MRT estimates derived from a mixture of waters with different ages (and thus different tracer concentrations) will systematically underestimate the mixture's true mean age. Here, building on recent work with stable isotope tracers in surface waters [1-3], we present a new framework for using 3H, 3He and 14C to characterize groundwater age distributions. Rather than describing groundwater age distributions by their MRT, we characterize them by the fraction of the distribution that is younger or older than a threshold age. The threshold age that separates "young" from "old" water depends on the characteristics of the specific tracer, including its history of atmospheric inputs. Our approach depends only on whether a given slice of the age distribution is younger or older than the threshold age, but not on how much younger or older it is. Thus our approach is insensitive to the tails of the age distribution, and is therefore relatively unaffected by uncertainty in the distribution's shape. Here we show that concentrations of 3H, 3He, and 14C are almost linearly related to the fractions of water that are younger or older than specified threshold ages. These

  15. Evidence for the emission of a 17-keV neutrino in the β decay of 14C

    International Nuclear Information System (INIS)

    We have studied the β spectrum of 14C using a germanium detector containing a crystal with 14C dissolved in it. We find a feature in the β spectrum 17 keV below the end point which can be explained by the hypothesis that there is a heavy neutrino emitted in the β decay of 14C with a mass of 17±2 keV and an emission probability of (1.40±0.45±0.14)%

  16. A study on Helicobacter pylori infection in different parts of Karnataka using 14C urea breath test

    International Nuclear Information System (INIS)

    A non-invasive 14C Urea Breath Test (14C UBT) technique was used for the diagnosis of Helicobacter pylori (H pylori) infection in symptomatic and asymptomatic individuals. The test utilises 14CO2 released due to the action of urease produced by H pylori. 14C UBT is found to be a simple alternative for endoscopic examinations for diagnosing H pylori infection. The test was performed on 664 subjects from various parts of Karnataka. Among them 34.9% of the subjects were found to be H pylori positive, and the infection rate varied from 16.9% to 38.6%. (author)

  17. Dissipation and degradation of /sup 14/C-DDT in potohar area Islamabad soil under field conditions

    International Nuclear Information System (INIS)

    An experiment in Potohar area Islamabad environment was conducted for one and a half years to investigate the dissipation and degradation of /sup 14/C-DDT in soil. Binding of /sup 14/C-DDT to the soil increased gradually with the passage of time. The extractable residues decreased in the same period. Results also revealed that /sup 14/C-DDT dissipated more rapidly in this environment as compared to the temperate regions. The overall half-life of DOT was 260 days. (author)

  18. Effect of parathion and aldrin on survival, ovarian 32P-uptake and gonadotrophic potency in a freshwater catfish, Heteropneustes fossilis (Bloch)

    International Nuclear Information System (INIS)

    The effects of insecticides containing either an organophosphate parathion (Paramar M 50) or an organochlorine aldrin on the survival, ovarian 32P uptake and the gonadotrophic potency of the pituitary gland and blood serum in Heteropneustes fossilis were studied for 4 weeks. Aldrin was found to be more toxic than Paramar M 50. Reduced ovarian 32P uptake and a significantly decreased level of total gonadotropin in the pituitary gland and blood serum were seen when fish were kept either in safe concentration or in a concentration that had been found to kill half the fish in 96 h of Aldrin and Paramar M 50. The data suggest that these insecticides retarded gonadotropin secretion which in turn reduced ovarian 32P uptake

  19. A practical process for the preparation of [32P]S1P and binding assay for S1P receptor ligands

    International Nuclear Information System (INIS)

    Sphingosine-1-phosphate receptors (S1PRs) are important regulators of vascular permeability, inflammation, angiogenesis and vascular maturation. Identifying a specific S1PR PET radioligand is imperative, but it is hindered by the complexity and variability of current for binding affinity measurement procedures. Herein, we report a streamlined protocol for radiosynthesis of [32P]S1P with good radiochemical yield (36–50%) and high radiochemical purity (>99%). We also report a reproducible procedure for determining the binding affinity for compounds targeting S1PRs in vitro. - Highlights: • Streamlined [32P]S1P production process with reproducible radiochemical yield. • Simplified assay of binding affinity for S1P receptors using [32P]S1P. • Reliable and repeatable IC50 values can be obtained by the reported method

  20. Differences in detection of DNA adducts in the 32P-postlabelling assay after either 1-butanol extraction or nuclease P1 treatment.

    Science.gov (United States)

    Gallagher, J E; Jackson, M A; George, M H; Lewtas, J; Robertson, I G

    1989-04-01

    The use of nuclease P1 treatment and 1-butanol extraction to increase the sensitivity of the 32P-postlabelling assay for DNA adducts have been compared. Although similar results were obtained with the two methods for standard adducts formed with benzo[a]pyrene diol epoxide I (BPDE-I), nuclease P1 treatment resulted in a significant reduction in detection of major adducts from 1-amino-6-nitropyrene (1-amino-6-NP), 1-amino-8-nitropyrene (1-amino-8-NP), 2-aminofluorene (2-AF), 2-naphthylamine (2-NA) and 4-aminobiphenyl (4-ABP) modified DNAs, but not following the 32P-postlabelling analysis of 2-acetylaminofluorene (2-AAF) modified DNA. These results suggest that, at least initially, both modifications of the 32P-postlabelling assay should be used for the detection of unknown adducts or for adducts derived from nitroaromatics and aromatic amines. PMID:2540901

  1. Differences in detection of DNA adducts in the 32P-postlabelling assay after either 1-butanol extraction or nuclease Pl treatment

    International Nuclear Information System (INIS)

    The use of nuclease P1 treatment and 1-butanol extraction to increase the sensitivity of the 32P-postlabelling assay for DNA adducts have been compared. Although similar results were obtained with the two methods for standard adducts formed with benzo(a)pyrene diol epoxide I, nuclease P1 treatment resulted in a significant reduction in detection of major adducts 1-amino-6-nitropyrene, 1-amino-8-nitropyrene, 2-aminofluorene, 2-naphthylamine and 4-aminobiphenyl modified DNAs, but not following the 32P-postlabelling analysis of 2-acetylaminofluorene modified DNA. These results suggest that at least initially, both modications of the 32P-postlabelling assay should be used for the detection of unknown adducts or for adducts derived from nitro-aromatics and aromatic amines

  2. Recombinase Polymerase Amplification (RPA) of CaMV-35S Promoter and nos Terminator for Rapid Detection of Genetically Modified Crops

    OpenAIRE

    Chao Xu; Liang Li; Wujun Jin; Yusong Wan

    2014-01-01

    Recombinase polymerase amplification (RPA) is a novel isothermal DNA amplification and detection technology that enables the amplification of DNA within 30 min at a constant temperature of 37–42 °C by simulating in vivo DNA recombination. In this study, based on the regulatory sequence of the cauliflower mosaic virus 35S (CaMV-35S) promoter and the Agrobacterium tumefaciens nopaline synthase gene (nos) terminator, which are widely incorporated in genetically modified (GM) crops, we designed t...

  3. Formation of bound residues of [benzene ring-U-14C]-anilazine and [triazine-U-14C]-anilazine in parabraunerde (Alfisol soil) and their availability to maize

    International Nuclear Information System (INIS)

    [Benzene ring-U-14C]-anilazine and [triazine-U-14C]-anilazine were incubated in a degraded loess soil (Alfisol) in accordance with standard guidelines of the U.S. Environmental Protection Agency for studying pesticide degradation in soil. The evolution of 14CO2 was measured and soil samples were extracted at certain intervals using different extraction procedures. After 100 days, the bioavailability to maize plants of the bound residue fractions was studied. The data indicate that 14C derived from anilazine is strongly adsorbed or fixed in the soil. Within a few days after 14C-anilazine application, the uptake of radioactivity by maize amounted to 3-4%. The uptake of unextractable radiocarbon was less than 1% of the applied radioactivity. (author)

  4. 胶体~(32) P-磷酸铬间质给药对犬累积损伤效应的研究%Cumulative damage effect of ~(32) P-colloidal chromic phosphate interstitial delivery on beagles

    Institute of Scientific and Technical Information of China (English)

    聂琦; 刘璐; 刘志勇; 黄培林; 兰兴昊; 高海林; 吴清华; 孙晋; 黄鹰

    2010-01-01

    目的 探讨胶体~(32)P-磷酸铬(~(32)P-CP)在正常Beagle犬的肝叶或臀大肌行间质注射的安全性.方法 10只Beagle犬,随机分成间质给药不同剂量(185和370 MBq)、不同部位(臀大肌和肝脏)及冷胶体对照5组(n=2).术后不同时间点称量体重,行血液生化学检查,ECT轫致辐射显像,组织形态学动态观察及连续测量体表、血液、尿液和粪便放射性计数率值.计量数据以均数±标准差((x)±s)表示,采用SPSS 13.0软件进行统计分析.结果 给药后ECT示肝脏组全肝显影,放射性分布呈团块状不均匀,肌肉组局部放射性持续浓聚,肝脏未见显影.术后第4组犬体重进行性减少,45 d时较术前减少2.7 kg,余组体重增值均数依序为3.0、1.6、0.8和3.1 kg.第4组血小板、红细胞术后有明显减少.分别于给药后23和45 d死亡,死亡前谷草转氨酶和谷丙转氨酶均有急剧升高;其余组间血液和血生化学差异无统计学意义.术后体表分区测定以注射部位放射性计数率值为最高,其次为膀胱、脾.肝脏组血液峰时为5 rain,峰值分别为0.5×10~7/min和1.0×10~7/min;肌肉组持续在3×10~5/min左右.组织学表现肌肉组和肝脏185 MBq组4周内有充血水肿改变,8周后组织结构恢复正常;肝脏370 MBq组4周内部分肝细胞坏死,6周时见大量肝细胞气球样变,充血水肿明显,肝小叶结构不清.尿液、粪便中放射性计数率肌肉组峰时均数分别为13和12 d,峰值为(42.0 ±3.3)x 10~4/min和(29.6±4.5)×10~4/min;肝脏组峰时为5和9 d,峰值为(49.0±10.2)×10~4/min和(28.5±7.1)×10~4/min.至30 d肌肉组从尿液和粪便中累积排泄率为36.58%和10.62%,肝脏组为23.48%和8.76%.吸收剂量肝脏组肝脏为(30.6 ±2.3)、(55.6±4.4)Gy;肌肉组肌肉注射部位为(53.4±3.1)、(98.1±3.3)Gy,肝脏为(2.3±1.3)、(6.5±1.2)Gy.结论 Beagle犬肝脏间质注射794.39 MBq/m~2,肝脏吸收剂量为56 Gy时有较强肝毒性及全身毒副作用,

  5. Evaluation of Soil Labile Phosphorus Using a Double—Labeling (32P and 33P) Technique

    Institute of Scientific and Technical Information of China (English)

    WANGGUANG-HUO

    1992-01-01

    Isotopic exchangeability of phosphorus in four Chinese soils with and without P application was studied by 32P and 33P double-labeling technique in relation to routine chemical extractions.The results showed that Bray-I and Bray-Ⅱ reagents could extract most of the fast exchangeable P.Not all of the Olsen-P belonged to fast exchangeable P,but it was about the same quantity of fast exchangeable P in a calcareous soil and a neutral soil without P application.Sequential fractionation of the soil phosphorus showed that most of the added radioisotopes in high P fixation red soils were tightly held by iron and aluminium oxides,which could be totally extracted only by 0.1M NaOH solution.In the neutral and calcareous soils most of the radioisotopes added were loosely held on the surface of soil particles and could be extracted by anion exchange resin.Phosphate application increased the resin-P fraction significantly for all the soils studied.

  6. /sup 32/P-Postlabeling test for covalent DNA binding of chemicals in vivo: Application to a variety of aromatic carcinogens and methylating agents

    Energy Technology Data Exchange (ETDEWEB)

    Reddy, M.V.; Gupta, R.C.; Randerath, E.; Randerath, K.

    1984-02-01

    Carcinogen--DNA adducts were detected and determined by /sup 32/P-postlabeling assay after exposure of mouse or rat tissues in vivo to a total of 28 compounds comprising 7 arylamines and derivatives, 3 azo compounds, 2 nitroaromatics, 12 polycyclic aromatic hydrocarbons, and 4 methylating agents. DNA was isolated from mouse skin, mouse liver, and rat liver after treatment with the individual carcinogens, then digested enzymatically to deoxyribonucleoside 3'-monophosphates, which were converted to 5'-/sup 32/P-labeled deoxyribonucleoside 3',5'-bisphosphates by T4 polynucleotide kinase-catalyzed (/sup 32/P)phosphate transfer from (gamma-/sup 32/P)ATP. The nucleotides were resolved by anion-exchange t.l.c. on polyethyleneimine-cellulose and detected by autoradiography. The determination of low levels of DNA binding of the aromatic carcinogens entailed the removal of normal nucleotides prior to the resolution of adduct nucleotides. For this purpose, an alternative procedure employing reversed-phase t.l.c. was devised which offered advantages for the detection of quantitatively minor adducts. The procedures described enabled the detection of 1 aromatic DNA adduct in approximately 10(/sup 8/) normal nucleotides, while the limit of detection of methylated adducts was 1 adduct in approximately 6 X 10(/sup 5/) nucleotides. The results show that a great number of carcinogen-DNA adducts of diverse structure are substrates for /sup 32/P-labeling by polynucleotide kinase-catalyzed phosphorylation. Because covalent DNA adduct formation in vivo appears to be an essential property of the majority of chemical carcinogens, /sup 32/P-postlabeling analysis of carcinogen--DNA adducts in mammalian tissues may serve as a test for the screening of chemicals for potential carcinogenicity.

  7. 32P-Postlabeling test for covalent DNA binding of chemicals in vivo: Application to a variety of aromatic carcinogens and methylating agents

    International Nuclear Information System (INIS)

    Carcinogen--DNA adducts were detected and determined by 32P-postlabeling assay after exposure of mouse or rat tissues in vivo to a total of 28 compounds comprising 7 arylamines and derivatives, 3 azo compounds, 2 nitroaromatics, 12 polycyclic aromatic hydrocarbons, and 4 methylating agents. DNA was isolated from mouse skin, mouse liver, and rat liver after treatment with the individual carcinogens, then digested enzymatically to deoxyribonucleoside 3'-monophosphates, which were converted to 5'-32P-labeled deoxyribonucleoside 3',5'-bisphosphates by T4 polynucleotide kinase-catalyzed [32P]phosphate transfer from [gamma-32P]ATP. The nucleotides were resolved by anion-exchange t.l.c. on polyethyleneimine-cellulose and detected by autoradiography. The determination of low levels of DNA binding of the aromatic carcinogens entailed the removal of normal nucleotides prior to the resolution of adduct nucleotides. For this purpose, an alternative procedure employing reversed-phase t.l.c. was devised which offered advantages for the detection of quantitatively minor adducts. The procedures described enabled the detection of 1 aromatic DNA adduct in approximately 10(8) normal nucleotides, while the limit of detection of methylated adducts was 1 adduct in approximately 6 X 10(5) nucleotides. The results show that a great number of carcinogen-DNA adducts of diverse structure are substrates for 32P-labeling by polynucleotide kinase-catalyzed phosphorylation. Because covalent DNA adduct formation in vivo appears to be an essential property of the majority of chemical carcinogens, 32P-postlabeling analysis of carcinogen--DNA adducts in mammalian tissues may serve as a test for the screening of chemicals for potential carcinogenicity

  8. Possible consequences of the overlap between the CaMV 35S promoter regions in plant transformation vectors used and the viral gene VI in transgenic plants.

    Science.gov (United States)

    Podevin, Nancy; du Jardin, Patrick

    2012-01-01

    Multiple variants of the Cauliflower mosaic virus 35S promoter (P35S) are used to drive the expression of transgenes in genetically modified plants, for both research purposes and commercial applications. The genetic organization of the densely packed genome of this virus results in sequence overlap between P35S and viral gene VI, encoding the multifunctional P6 protein. The present paper investigates whether introduction of P35S variants by genetic transformation is likely to result in the expression of functional domains of the P6 protein and in potential impacts in transgenic plants. A bioinformatic analysis was performed to assess the safety for human and animal health of putative translation products of gene VI overlapping P35S. No relevant similarity was identified between the putative peptides and known allergens and toxins, using different databases. From a literature study it became clear that long variants of the P35S do contain an open reading frame, when expressed, might result in unintended phenotypic changes. A flowchart is proposed to evaluate possible unintended effects in plant transformants, based on the DNA sequence actually introduced and on the plant phenotype, taking into account the known effects of ectopically expressed P6 domains in model plants.

  9. Possible consequences of the overlap between the CaMV 35S promoter regions in plant transformation vectors used and the viral gene VI in transgenic plants.

    Science.gov (United States)

    Podevin, Nancy; du Jardin, Patrick

    2012-01-01

    Multiple variants of the Cauliflower mosaic virus 35S promoter (P35S) are used to drive the expression of transgenes in genetically modified plants, for both research purposes and commercial applications. The genetic organization of the densely packed genome of this virus results in sequence overlap between P35S and viral gene VI, encoding the multifunctional P6 protein. The present paper investigates whether introduction of P35S variants by genetic transformation is likely to result in the expression of functional domains of the P6 protein and in potential impacts in transgenic plants. A bioinformatic analysis was performed to assess the safety for human and animal health of putative translation products of gene VI overlapping P35S. No relevant similarity was identified between the putative peptides and known allergens and toxins, using different databases. From a literature study it became clear that long variants of the P35S do contain an open reading frame, when expressed, might result in unintended phenotypic changes. A flowchart is proposed to evaluate possible unintended effects in plant transformants, based on the DNA sequence actually introduced and on the plant phenotype, taking into account the known effects of ectopically expressed P6 domains in model plants. PMID:22892689

  10. 14CO2-assimilation, translocation of 14C, and 14C-carbonate uptake in different organs of spring barley plants in relation to adult-plant resistance to powdery mildew

    International Nuclear Information System (INIS)

    The cultivar Peruvian of spring barley, which is susceptible at all growth stages, and Asse, which exhibits adult-plant resistance to powdery mildew, were compared in 14CO2 assimilation, distribution of 14C, and 14C-carbonate uptake in different organs of healthy and infected plants. The reduction of 14CO2 assimilation in infected plants at the first and fourth leaf stages was greater in Peruvian than in Asse. In Peruvian, the 14C which was fixed by the infected third leaf of plants with mildew on the lower 3 leaves remained in the third leaves with very little translocation to other parts of the plant. Infection of the lower three leaves at the fourth leaf stage reduced 14CO2 assimilation in noninfected fourth leaves of Asse less than that of Peruvian, but the flow of 14C from the healthy fourth leaves into other plant parts such as leaf sheaths was markedly stimulated in Peruvian compared to Asse. Infection also reduced the uptake of 14C-carbonate by seedling roots, the reduction being greater in Peruvian than Asse. A greater proportion of the 14C absorbed by roots of Asse was translocated to the infected leaves than that of Peruvian. It was concluded that powdery mildew disrupted the normal pattern of photosynthesis and translocation of metabolites in a susceptible cultivar more markedly than in an adult-plant-resistant cultivar of spring barley. (author)

  11. Ratio and rate effects of 32P-triple superphosphate and phosphate rock mixtures on corn growth Proporções e doses das misturas de 32P-superfosfato triplo com fosfato natural no desenvolvimento do milho

    Directory of Open Access Journals (Sweden)

    Vinícius Ide Franzini

    2009-02-01

    Full Text Available The availability of phosphorus (P from " Patos de Minas" phosphate rock (PR can be improved if it is applied mixed with a water-soluble P source. The objective of this study was to evaluate 32P as a tracer to quantify the effect of the ratio of mixtures of triple superphosphate (TSP with PR and the rates of application on P availability from PR. Two experiments were conducted in a greenhouse utilizing corn (Zea mays L. plants as test crop. In the first experiment, the P sources were applied at the rate of 90 mg P kg-1 soil either separately or as compacted mixtures in several TSP:PR ratios (100:0, 80:20, 60:40, 50:50, 40:60, 20:80 and 0:100 calculated on the basis of the total P content. In the second experiment, the TSP was applied alone or as 50:50 compacted mixtures with PR applied at four P rates (15, 30, 60 and 90 mg P kg-1 while the sole PR treatment was applied at the 90 mg kg-1 P rate . The mixture of PR with TSP improved the P recovery from PR in the corn plant and this effect increased proportionally to the TSP amounts in the mixture. When compared with the plant P recovery from TSP (10.52%, PR-P recovery (2.57% was much lower even when mixed together in the ratio of 80% TSP: 20% PR. There was no difference in PR-P utilization by the corn plants with increasing P rates in the mixture (1:1 proportion. Therefore, PR-P availability is affected by the proportions of the mixtures with water soluble P, but not by P rates.A disponibilidade de fósforo do fosfato natural de Patos de Minas (FN pode ser melhorada se aplicado junto com uma fonte de P solúvel em água. O objetivo desse estudo foi usar o 32P como traçador para quantificar o efeito das doses e das proporções das misturas de superfosfato triplo (SFT com FN no aumento da disponibilidade de P do FN. Dois experimentos foram desenvolvidos em casa-de-vegetação com plantas de milho (Zea mays L. como cultura teste. No primeiro experimento as fontes de fósforo, na dose de 90 mg kg-1

  12. Hydrochemical modelling and determination of 14C ages of geothermal waters in Kizildere and Tekkehamam fields

    International Nuclear Information System (INIS)

    Many geothermal fluids are encountered as springs and wells in the area between Buharkent - Yenice - Pamukkale located in the Aegean Region to the east of the Bueyuek Menderes Graben. This study, constituting a part of the project called 'Age and Origin Determination of the High Temperature Geothermal Fluids in the Bueyuek Menderes Graben' and directed by the MTA General Directorate, aims the recharge and circulation period verification of related resources by means of interpreting isotopic and hydrochemical data of the above mentioned region. For this purpose, water chemistry, δ18O, δ2H, δ3H, 14C, δ34S-SO4 ve δ18O-SO4 isotope sampling have been realized in order to determine the geochemical processes taken place in underground. As a result of the study the origin, the recharge altitudes and the circulation periods of grouped fluids with temperatures between 35 degrees- 242 degreeslocated in the region were clarified. According to the given chemical data, hydrochemically characterized waters are classified in 10 different types. It has been indicated that, six subtypes of the classification are constituted from the mixtures of waters at 242 degreesand 4th type Na-HCO3 belonging to Kizildere thermal waters, first type Ca-HCO3 waters, second type Ca-HCO3-SO4 waters and third type Ca-SO4 waters. According to the evaluation of the 14C isotope, the geothermal fluid discharging from the Kizildere Power Plant, corresponds to a turnovertime of 22.500 - 27.500 years. Previous studies reveal that the waters of the Tekkehamam geothermal field originate from the mixture of shallow groundwaters encountered in the site with geothermal fluids underflowing from the Kizildere geothermal field, in north-south direction. Taken into consideration this mentioned mixture model, the 14C isotope indicates a turnovertime of 31.000 years for R-1 geothermal well and 35.000 years for the нnatlм spring, located in the Tekkehamam geothermal field

  13. Insights from 14C into C loss pathways in degraded peatlands

    Science.gov (United States)

    Evans, Martin; Evans, Chris; Allott, Tim; Stimson, Andrew; Goulsbra, Claire

    2016-04-01

    Peatlands are important global stores of terrestrial carbon. Lowered water tables due to changing climate and direct or indirect human intervention produce a deeper aerobic zone and have the potential to enhance loss of stored carbon from the peat profile. The quasi continuous accumulation of organic matter in active peatlands means that the age of fluvial dissolved organic carbon exported from peatland systems is related to the source depth in the peat profile. Consequently 14C analysis of DOC in waters draining peatlands has the potential not only to tell us about the source of fluvial carbon and the stability of the peatland but also about the dominant hydrological pathways in the peatland system. This paper will present new radiocarbon determinations from peatland streams draining the heavily eroded peatlands of the southern Pennine uplands in the UK. These blanket peatland systems are highly degraded, with extensive bare peat and gully erosion resulting from air pollution during the industrial revolution, overgrazing, wildfire and climatic changes. Deep and extensive gullying has significantly modified the hydrology of these systems leading to local and more widespread drawdown of water table. 14C data from DOC in drainage waters are presented from two catchments; one with extensive gully erosion and the other with a combination of gully erosion and sheet erosion of the peat. At the gully eroded site DOC in drainage waters is as old as 160 BP but at the site with extensive sheet erosion dates of up to 1069 BP are amongst the oldest recorded from blanket peatland globally These data indicate significant degradation of stored carbon from the eroding peatlands. Initial comparisons of the 14C data with modelled water table for the catchments and depth-age curves for catchment peats suggests that erosion of the peat surface, allowing decomposition of exposed older organic material is a potential mechanism producing aged carbon from the eroded catchment. This

  14. Distribution of {delta}{sup 14}C in western North Pacific and tracing carbons of human origin

    Energy Technology Data Exchange (ETDEWEB)

    Aramaki, Takafumi; Mizushima, Toshihiko; Togawa, Orihiko [Japan Atomic Energy Research Inst., Mutsu, Aomori (Japan). Mutsu Establishment; Watanabe, Shuichi; Tsunogai, Shizuo [Hokkaido Univ., Sapporo (Japan); Kuji, Tomoyuki [Japan marine Sience Fundation, Mutsu, Aomori (Japan)

    2001-02-01

    Seawater were collected at six points, 0deg to 48degN around 165degE. Dissolved inorganic carbonates was reduced into graphite. The ratio C-11/C-12 was measured by the accelerator mass analyzer. {sup 14}C concentration was calculated from {delta}{sup 13}C value calculated from the {sup 13}C/{sup 12}C ratio. {sup 14}C resulting from the nuclear weapon test was calculated by comparing estimated {sup 14}C and real {sup 14}C concentration. It was compared with that in 1970s. {sup 14}Cbomb has dissolved into North Pacific Intermediate Water in Arctic latitude, which has moved to Mid-latitude. (A. Yamamoto)

  15. Uptake and expulsion of sup 14 C-xylitol by xylitol-cultured Streptococcus mutans ATCC 25175 in vitro

    Energy Technology Data Exchange (ETDEWEB)

    Soederling, E.; Pihlanto-Leppaelae, A. (Department of Biochemistry, Institute of Dentistry, University of Turku, Turku (Finland))

    1989-01-01

    The effect of successive cultivations in the presence of 6% xylitol on the uptake and expulsion of {sup 14}C-xylitol was studied using the cells of Streptococcus mutans 25175. Three sequential cultivations did not alter the growth inhibition percentage (approximately 50%) observed in the presence of 6% xylitol. The {sup 14}C-xylitol uptake experiments performed with growing and resting cells showed that both the uptake and the expulsion of xylitol were enhanced by xylitolculturing. Both xylitol-cultured and resting control cells contained only one major labeled compound which was identified as {sup 14}C-xylitol 5-phosphate. The label subsequently was expelled from the cells as {sup 14}C-xylitol. These results indicate that S. mutans possesses an intracellular xylitol cycle and this cycle is regulated by adding xylitol to the growth medium. (author).

  16. In vivo inhibition of incorporation of (U-/sup 14/C)glucose into proteins in experimental focal epilepsy

    Energy Technology Data Exchange (ETDEWEB)

    Coutinho-Netto, J.; Boyar, M.M.; Abdul-Ghani, A.S.; Bradford, H.F.

    1982-08-01

    The in vivo incorporation of (/sup 14/C) from (U-/sup 14/C)-glucose into rat brain proteins from different cortical areas was examined in three different experimental focal epilepsies: cobalt, freeze-lesions, and tityustoxin. When (U-/sup 14/C)-glucose was injected intraperitoneally into awake and unrestrained animals with marked signs of epileptic hyperactivity, the inhibition of incorporation of (/sup 14/C)-amino acids into trichloracetic acid (TCA)-insoluble proteins was highest in the focal (sensorimotor) area when compared with distant regions (approx. 60%), but less when compared with the contralateral (sensorimotor) region (approx. 23%). Greatly decreased incorporation caused by both cobalt and freeze-lesion-induced epilepsies was also observed in the contralateral area when a comparison was made with distant regions (approx. 50%), but there were no significant differences in protein-specific radioactivity between the different distant areas.

  17. Uptake and expulsion of 14C-xylitol by xylitol-cultured Streptococcus mutans ATCC 25175 in vitro

    International Nuclear Information System (INIS)

    The effect of successive cultivations in the presence of 6% xylitol on the uptake and expulsion of 14C-xylitol was studied using the cells of Streptococcus mutans 25175. Three sequential cultivations did not alter the growth inhibition percentage (approximately 50%) observed in the presence of 6% xylitol. The 14C-xylitol uptake experiments performed with growing and resting cells showed that both the uptake and the expulsion of xylitol were enhanced by xylitolculturing. Both xylitol-cultured and resting control cells contained only one major labeled compound which was identified as 14C-xylitol 5-phosphate. The label subsequently was expelled from the cells as 14C-xylitol. These results indicate that S. mutans possesses an intracellular xylitol cycle and this cycle is regulated by adding xylitol to the growth medium. (author)

  18. On the characteristics of cosmogenic in situ 14C in some GISP2 Holocene and late glacial ice samples

    International Nuclear Information System (INIS)

    In previous studies, we have shown that information on ice accumulation processes is recorded by the in situ production of 14C, from nuclear interactions of cosmic rays with oxygen in ice (Lal et al., 1997). In this report, we discuss a study of a number of Holocene and several glacial ice samples from the GISP2 core whose accumulation rates are known and which should be little affected by uncertainties in ice flow models (Cuffey et al., 1997), to determine trapping efficiencies of in situ 14C. We present new results along with discussion of the earlier results of Lal et al. (1997), which include results on partitioning of in situ 14C among the CO and CO2 phases through time in ice. The usefulness of the in situ 14C data to measurements of ice accumulation rates and ages are discussed

  19. Degradation of Triazine-2-14C Metsulfuron–Methyl in Soil from an Oil Palm Plantation

    OpenAIRE

    Ismail, B. S.; O K Eng; M A Tayeb

    2015-01-01

    Triazine-2-(14)C metsulfuron-methyl is a selective, systemic sulfonylurea herbicide. Degradation studies in soils are essential for the evaluation of the persistence of pesticides and their breakdown products. The purpose of the present study was to investigate the degradation of triazine-2-(14)C metsulfuron-methyl in soil under laboratory conditions. A High Performance Liquid Chromatograph (HPLC) equipped with an UV detector and an on-line radio-chemical detector, plus a Supelco Discovery co...

  20. Metabolism and macromolecular covalent binding of [14C]-1-nitropyrene in isolated perfused and ventilated rat lungs

    International Nuclear Information System (INIS)

    The purpose of this study was to quantitate l-nitropyrene (1-NP) metabolism and macromolecular covalent binding in the isolated perfused rat lung. Rat lungs were perfused with 2, 5, or 24 microM [14C]-1-NP for 90 min. Tidal volume and dynamic lung compliance were monitored throughout the perfusion to document the ventilatory pattern and the decay of tissue elasticity. Perfusate was sampled periodically throughout the experiment and analyzed for 1-NP metabolites with high-performance liquid chromatography. In all experiments, both dynamic lung compliance and tidal volume declined in a nearly linear manner and were approximately 60% of the initial value at the end of 90 min of perfusion. At all concentrations of [14C]-1-NP tested, less than 5 to 6% of the total amount of [14C]-1-NP added was metabolized in lungs from control and phenobarbital (PB)-treated rats. Lungs from control and PB- and 3-methylcholanthrene (3-MC)-treated rats metabolized [14C]-1-NP to oxidized, reduced, and conjugated metabolites. The major metabolites were 3-, 6-, and 8-hydroxynitropyrene. Treatment of rats with PB resulted in a 60% increase in the total metabolism of [14C]-1-NP, whereas treatment of rats with 3-MC resulted in a 10-fold increase in the rate of metabolism of [14C]-1-NP when compared to controls. Conjugate hydrolysis studies indicated that the water-soluble metabolites from lungs of control and PB- and 3-MC-treated rats consisted of hydroxynitropyrene glucuronides and hydroxynitropyrene sulfate conjugates. Quantities of 14C covalently bound to lung macromolecules after 90 min of perfusion from lungs of control and PB-treated rats were 0.06 to 0.21 nmol equivalents/g lung. However, in lungs from 3-MC-treated rats, there was a 20-fold increase in quantities of 14C covalently bound when compared to lungs from either control or PB-treated rats