Improvement of Emulsifying Properties of Wheat Gluten Hydrolysate λ-Carrageenan Conjugates

Directory of Open Access Journals (Sweden)

Jin-Shui Wang

2006-01-01

Full Text Available Gluten hydrolysate was prepared through limited enzymatic hydrolysis of wheat gluten resulting from the byproducts of wheat starch. The enzyme applied in the present study was Protamex. Response surface methodology was used to investigate the effects of pH, gluten hydrolysate (GHPλ-carrageenan (C ratio and reaction time on emulsifying properties of the GHP-C conjugate. The regression model for emulsion activity index (EAI was significant at p=0.001, while reaction time had a significant effect on EAI of the conjugate with regression coefficient of 4.25. The interactions of pH and GHP/ C ratio, and GHP/C ratio and reaction time significantly affected the EAI of the conjugate. Both the emulsifying property and nitrogen solubility index (NSI of GHP-C conjugate prepared under the optimal conditions increased more remarkably, compared to the control. The denaturation temperature of GHP-C conjugate obviously increased compared to wheat gluten. The addition of GHP-C conjugate had different effects on dough characteristics. Moreover, this conjugate can delay the increase in the bread crumb firmness during storage. It demonstrated that this conjugate couldimprove the dough characteristics and had anti-staling properties of bread.

DOTA-PESIN, a DOTA-conjugated bombesin derivative designed for the imaging and targeted radionuclide treatment of bombesin receptor-positive tumours

Energy Technology Data Exchange (ETDEWEB)

Zhang, Hanwen; Maecke, Helmut R. [University Hospital Basel, Division of Radiological Chemistry, Department of Radiology, Basel (Switzerland); Schuhmacher, Jochen; Eisenhut, Michael [German Cancer Research Centre, Department of Radiopharmaceutical Chemistry, Heidelberg (Germany); Waser, Beatrice; Reubi, Jean Claude [University of Berne, Division of Cell Biology and Experimental Cancer Research, Institute of Pathology, P.O. Box 62, Berne (Switzerland); Wild, Damian [University Hospital, Clinic and Institute of Nuclear Medicine, Department of Radiology, Basel (Switzerland)

2007-08-15

We aimed at designing and developing a novel bombesin analogue, DOTA-PEG{sub 4}-BN(7-14) (DOTA-PESIN), with the goal of labelling it with {sup 67/68}Ga and {sup 177}Lu for diagnosis and radionuclide therapy of prostate and other human cancers overexpressing bombesin receptors. The 8-amino acid peptide bombesin (7-14) was coupled to the macrocyclic chelator DOTA via the spacer 15-amino-4,7,10,13-tetraoxapentadecanoic acid (PEG{sub 4}). The conjugate was complexed with Ga(III) and Lu(III) salts. The GRP receptor affinity and the bombesin receptor subtype profile were determined in human tumour specimens expressing the three bombesin receptor subtypes. Internalisation and efflux studies were performed with the human GRP receptor cell line PC-3. Xenografted nude mice were used for biodistribution. [Ga{sup III}/Lu{sup III}]-DOTA-PESIN showed good affinity to GRP and neuromedin B receptors but no affinity to BB3. [{sup 67}Ga/{sup 177}Lu]-DOTA-PESIN internalised rapidly into PC-3 cells whereas the efflux from PC-3 cells was relatively slow. In vivo experiments showed a high and specific tumour uptake and good retention of [{sup 67}Ga/{sup 177}Lu]-DOTA-PESIN. [{sup 67}Ga/{sup 177}Lu]-DOTA-PESIN highly accumulated in GRP receptor-expressing mouse pancreas. The uptake specificity was demonstrated by blocking tumour uptake and pancreas uptake. Fast clearance was found from blood and all non-target organs except the kidneys. High tumour-to-normal tissue ratios were achieved, which increased with time. PET imaging with [{sup 68}Ga]-DOTA-PESIN was successful in visualising the tumour at 1 h post injection. Planar scintigraphic imaging showed that the {sup 177}Lu-labelled peptide remained in the tumour even 3 days post injection. The newly designed ligands have high potential with regard to PET and SPECT imaging with {sup 68/67}Ga and targeted radionuclide therapy with {sup 177}Lu. (orig.)

The study of conjugation of anti-CD20 monoclonal antibody for labeling with metallic or lanthanides radionuclides; Estudo de conjugacao do anticorpo anti-CD20 para marcacao com radionuclideos metalicos ou lantanideos

Energy Technology Data Exchange (ETDEWEB)

Akanji, Akinkunmi Ganiyu

2012-07-01

Lymphomas are malignancies or cancers that start from the malign transformation of a lymphocyte in the lymphatic system. Generally, lymphomas start from the lymph nodes or from the agglomeration of the lymphatic tissues, organs like stomach, intestines, in some cases it can involve the bone marrow and the blood, it can also disseminate to other organs. Lymphomas are divided in two major categories: Hodgkin lymphoma and non-Hodgkin lymphoma (NHL). Patient with NHL are generally treated with radiotherapy alone or combined with immunotherapy using monoclonal antibody rituximab (MabThera Registered-Sign ). Currently, monoclonal antibodies (Acm) conjugated with bifunctional chelate agents and radiolabeled with metallic or lanthanides radionuclides are a treatment reality for patients with NHL by the principle of radioimmunotherapy (RIT). This study focused on the conditions of conjugation of Acm rituximab (MabThera Registered-Sign ) with bifunctional chelating agents DOTA and DTPA. Various parameters were studied: method of Acm purification, conditions of Acm conjugation, the method for determination of number of chelate agent coupled to the Acm, method for purification of the conjugated antibody Acm, conditions of labeling of the conjugated antibody with lutetium-177, method of purification of the radiolabeled immuno conjugate, method of radiochemical purity (RP), specific binding in vitro Raji cells (Human Burkitt) and biological distribution performed in normal Balb-c mouse. The three methodologies employed in pre-purification of Acm (dialysis, size exclusion chromatograph and dial filtration) demonstrated to be efficient; they provided sample recovery exceeding 90%. However, the methodology of dial filtration presents minimal sample loss, and gave the final recovery of the sample in micro liters; thereby facilitating sample use in subsequent experiments. Numbers of chelators attached to the Acm molecule was proportional to the molar ratio studied. When we evaluated

Oceanic distributions of radionuclides from nuclear weapons testing

International Nuclear Information System (INIS)

Bowen, V.T.

1977-01-01

Data on the transport of fallout radionuclides in the Atlantic and Pacific Oceans are reviewed. Relevance of water column fallout data to the disposal of radioactive waste in marine locations is discussed. It is pointed out that regional patterns of delivery of soluble radionuclides must be assumed to persist at least for decades, in spite of the homogenizing action of ocean current systems and that, although there are delays in relation to density discontinuities in the water column, particle-associated radionuclides are generally delivered directly to the sediment surface. The chemistry of particle association appears increasingly complex, in relation both to the element selectivity among kinds of particles, and the stability of the associations once formed, and regional conditions may lead to retention of Pu (and possibly other nuclides) in discrete layers or throughout the water column, in opposition to its general tendency to associate with particles

Terrestrial pathways of radionuclide particulates

International Nuclear Information System (INIS)

Boone, F.W.; Ng, Y.C.

1981-01-01

Formulations are developed for computing potential human intake of 13 radionuclides via the terrestrial food chains. The formulations are an extension of the NRC methodology. Specific regional crop and livestock transfer and fractional distribution data from the southern part of the U.S.A. are provided and used in the computation of comparative values with those computed by means of USNRC Regulatory Guide 1.109 formulations. In the development of the model, emphasis was also placed on identifying the various time-delay compartments of the food chains and accounting for all of the activity initially deposited. For all radionuclides considered, except 137 Cs, the new formulations predict lower potential intakes from the total of all food chains combined than do the comparable Regulatory Guide formulations by as much as a factor of 40. For 137 Cs the new formulations predict 10% higher potential intakes. (author)

Clinical significant of three phase radionuclide bone scan

Energy Technology Data Exchange (ETDEWEB)

Kim, Sun Hee; Suh, Jin Suck; Park, Chang Yun [Yonsei University College of Medicine, Seoul (Korea, Republic of)

1989-04-15

Three phase radionuclide bone scan, consisting of a radionuclide angiogram, an immediate postinjection blood pool image, and 4hr delayed images, was randomly performed in 182 patients, who had been suffered from either local pain or tenderness. Authors analysed 3 phase bone scan in 74 patients with correct diagnosis proven surgically or clinically, from July 1987 to August, 1988. The results were as follows: 1. Overall sensitivity of 3 phase bone scan was 85.4%: sensitivity in patients with an osseous lesion was 90.4% as opposed to 72.7% in patients with a nonosseous lesion. 2. There was no difference in the detection rate of the osseous lesions between the 3 phase bone scan and the delayed image bone scan. However, because the detection rate was higher on the 3 phase bone scan than it was on only the delayed image bone scan (55%) in instance of the nonosseous lesion, we would suggest that 3 phase bone scan might be obtained in cases suspected of the nonosseous lesions. 3. When the presumptive diagnosis was a bone tumor, sensitivity and specificity for malignancy were 67%, 100% respectively. 4. In differentiating osteomyelitis from cellulitis, sensitivity was 94%, specificity was 100%. 5. 3 phase bone scan was able to provide the precise information about either vasculaturity or localization of lesion in some cases of soft tissue mass and avascular necrosis of hips.

The use of radiocobalt as a label improves imaging of EGFR using DOTA-conjugated Affibody molecule

DEFF Research Database (Denmark)

Garousi, Javad; Andersson, Ken G; Dam, Johan H

2017-01-01

-expressing xenografts in mice. An optimal combination of radionuclide, chelator and targeting protein may further improve the contrast of radionuclide imaging. The aim of this study was to evaluate the targeting properties of radiocobalt-labelled DOTA-ZEGFR:2377. DOTA-ZEGFR:2377 was labelled with (57)Co (T1/2 = 271.8 d......), (55)Co (T1/2 = 17.5 h), and, for comparison, with the positron-emitting radionuclide (68)Ga (T1/2 = 67.6 min) with preserved specificity of binding to EGFR-expressing A431 cells. The long-lived cobalt radioisotope (57)Co was used in animal studies. Both (57)Co-DOTA-ZEGFR:2377 and (68)Ga-DOTA......Several anti-cancer therapies target the epidermal growth factor receptor (EGFR). Radionuclide imaging of EGFR expression in tumours may aid in selection of optimal cancer therapy. The (111)In-labelled DOTA-conjugated ZEGFR:2377 Affibody molecule was successfully used for imaging of EGFR...

Detection and evaluation of left atrial myxoma by gated radionuclide imaging

International Nuclear Information System (INIS)

Sugihara, Hiroki; Adachi, Haruhiko; Nakagawa, Hiroaki

1985-01-01

Radionuclide imaging plays an important role in diagnosising left atrial myxoma (LAM). We discussed diagnostic value of Fourier analysis with phase image and evaluated left ventricular filling function using indices such as 1/3 Filling Fraction, Rapid Filling Fraction and Peak Filling Rate derived from left ventricular volume curve. Equillibrium radionuclide angiocardiography was performed in 6 LAM patients. Phase delay in the basal portion of the left ventricle was shown in 5 of 6 LAM patients, and standard deviation of left ventricular phase was larger than these of controls. Left ventricular filling disturbance was suggested in 5 of 6 LAM patients. After surgical remove of myxoma phase delay was disappeared and standard deviation was normalized. And left ventricular filling was improved. We concluded that the phase image of Fourier analysis revealed a left atrial mass prolapsing in the left ventricule during the diastole, and that diastolic indices were useful for left ventricular filling disturbance due to LAM. (author)

Microreactor and method for preparing a radiolabeled complex or a biomolecule conjugate

Energy Technology Data Exchange (ETDEWEB)

Reichert, David E; Kenis, Paul J. A.; Wheeler, Tobias D; Desai, Amit V; Zeng, Dexing; Onal, Birce C

2015-03-17

A microreactor for preparing a radiolabeled complex or a biomolecule conjugate comprises a microchannel for fluid flow, where the microchannel comprises a mixing portion comprising one or more passive mixing elements, and a reservoir for incubating a mixed fluid. The reservoir is in fluid communication with the microchannel and is disposed downstream of the mixing portion. A method of preparing a radiolabeled complex includes flowing a radiometal solution comprising a metallic radionuclide through a downstream mixing portion of a microchannel, where the downstream mixing portion includes one or more passive mixing elements, and flowing a ligand solution comprising a bifunctional chelator through the downstream mixing portion. The ligand solution and the radiometal solution are passively mixed while in the downstream mixing portion to initiate a chelation reaction between the metallic radionuclide and the bifunctional chelator. The chelation reaction is completed to form a radiolabeled complex.

A model for radionuclide transport in the Cooling Water System

International Nuclear Information System (INIS)

Kahook, S.D.

1992-08-01

A radionuclide transport model developed to assess radiological levels in the K-reactor Cooling Water System (CWS) in the event of an inadvertent process water (PW) leakage to the cooling water (CW) in the heat exchangers (HX) is described. During and following a process water leak, the radionuclide transport model determines the time-dependent release rates of radionuclide from the cooling water system to the environment via evaporation to the atmosphere and blow-down to the Savannah River. The developed model allows for delay times associated with the transport of the cooling water radioactivity through cooling water system components. Additionally, this model simulates the time-dependent behavior of radionuclides levels in various CWS components. The developed model is incorporated into the K-reactor Cooling Tower Activity (KCTA) code. KCTA allows the accident (heat exchanger leak rate) and the cooling tower blow-down and evaporation rates to be described as time-dependent functions. Thus, the postulated leak and the consequence of the assumed leak can be modelled realistically. This model is the first of three models to be ultimately assembled to form a comprehensive Liquid Pathway Activity System (LPAS). LPAS will offer integrated formation, transport, deposition, and release estimates for radionuclides formed in a SRS facility. Process water and river water modules are forthcoming as input and downstream components, respectively, for KCTA

Modelling for radiological and radioecological consequences of an accidental radionuclide release at Sea

International Nuclear Information System (INIS)

Paschoa, A.S.

1997-01-01

Full text: Scenarios concerning accidental releases of radionuclides into water bodies can be found in the open literature, mostly in connection with nuclear power plants located either onshore or inland. However, meager attention has been given to nuclear reactors used as energy sources for propulsion at sea, which are also subject to accidents. Such potential accidents may involve the loss of part of the reactor core to the surrounding water body. In addition of the initial instantaneous releases, one can estimate delayed source terms based on the rate at which radionuclides are dissolved or leached from the solidified material, like part of the core or structural materials in contact with water. Most of such solidified material might be a mixture of uranium, zirconium, iron, calcium, silica, fission and activation products, and transuranium elements as oxides, forming a glassy type solid. Transport models were used to calculate radionuclide concentrations in water resulting from short and delayed source terms. Oceanographic data used in the calculations were taken either from the open literature or from unclassified reports of the Brazilian Navy, being, however, as generic as possible. Time-dependent concentration functions for radionuclides in aquatic food following an accidental release reflect the net result of intake and elimination processes. However, to avoid the complexities of multiple parameters involved in such processes, the model accounts only for trophic transfer of radionuclides, and yet avoids the necessity of analyzing the details of each transfer step used to determine fish, crustacea, molluscs and seaweed accumulation. Swimming and other aquatic sports are not included in the model used for dose calculations because of theirs relatively low importance in comparison with the pathways concerning ingestion of aquatic food

Country report: Italy (Chinol). Pre-clinical evaluation of a new biotin-DOTA conjugate labeled with 90Y for application in pretargeting clinical protocols

International Nuclear Information System (INIS)

Chinol, Marco

2010-01-01

In the attempt to improve the therapeutic efficacy of radiolabeled mAbs in cancer radioimmunotherapy, various studies have examined the concept of tumor pretargeting. The so called three-step pretargeting technique, employing the avidin–biotin system, was applied in phase I-II clinical trials showing low toxicity and therapeutic efficacy. The final step of the pretargeting protocols consists in the systemic injection of radiolabeled biotin. The worldwide recognized “successful association” is between 90 Y and the tetraazamacrocycle DOTA chelator chemically bound to biotin. Improvements in the structure of the biotin-DOTA conjugate have been reported by our group following a novel approach which simplified the synthetic pattern by reducing the amide group to a methylene group, thus transforming the amide into a secondary amine without affecting the length of the biotin side arm. Preliminary in-vitro experiments, previously published by our group, indicated the potential of the new conjugate. Based on our previous experience with avidin-based pre-targeting followed 90 Y-DOTA-biotin in the locoregional treatment of peritoneal carcinomatosis and malignant glioma suggested that similar radionuclide therapy might be worth investigating as a partial replacement of external beam radiotherapy in breast cancer. We have developed IART® the Intra-operative Avidination for Radionuclide Therapy that relies on the avidin-biotin binding system. In fact, the “avidination” of the anatomical area of the tumor with native avidin, directly injected by the surgeon into and around the tumor bed, provides a target for the radiolabeled biotin intravenously (iv) injected one day later. In order to optimize the overall strategy, further efforts were needed to optimize the use of the labeled new biotin conjugate and to elucidate its chemical and biological properties. In the first 18 months of this CRP, the pre-clinical evaluation of this new reduced biotinamidohexylamine

Radionuclide toxicity

International Nuclear Information System (INIS)

Galle, P.

1982-01-01

The aim of this symposium was to review the radionuclide toxicity problems. Five topics were discussed: (1) natural and artificial radionuclides (origin, presence or emission in the environment, human irradiation); (2) environmental behaviour of radionuclides and transfer to man; (3) metabolism and toxicity of radionuclides (radioiodine, strontium, rare gas released from nuclear power plants, ruthenium-activation metals, rare earths, tritium, carbon 14, plutonium, americium, curium and einsteinium, neptunium, californium, uranium) cancerogenous effects of radon 222 and of its danghter products; (4) comparison of the hazards of various types of energy; (5) human epidemiology of radionuclide toxicity (bone cancer induction by radium, lung cancer induction by radon daughter products, liver cancer and leukaemia following the use of Thorotrast, thyroid cancer; other site of cancer induction by radionuclides) [fr

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

International Nuclear Information System (INIS)

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

1998-01-01

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

Country report: Italy (Chinol). Pre-clinical evaluation of a new biotin-DOTA conjugate labeled with {sup 90}Y for application in pretargeting clinical protocols

Energy Technology Data Exchange (ETDEWEB)

Chinol, Marco

2010-07-01

In the attempt to improve the therapeutic efficacy of radiolabeled mAbs in cancer radioimmunotherapy, various studies have examined the concept of tumor pretargeting. The so called three-step pretargeting technique, employing the avidin–biotin system, was applied in phase I-II clinical trials showing low toxicity and therapeutic efficacy. The final step of the pretargeting protocols consists in the systemic injection of radiolabeled biotin. The worldwide recognized “successful association” is between {sup 90}Y and the tetraazamacrocycle DOTA chelator chemically bound to biotin. Improvements in the structure of the biotin-DOTA conjugate have been reported by our group following a novel approach which simplified the synthetic pattern by reducing the amide group to a methylene group, thus transforming the amide into a secondary amine without affecting the length of the biotin side arm. Preliminary in-vitro experiments, previously published by our group, indicated the potential of the new conjugate. Based on our previous experience with avidin-based pre-targeting followed {sup 90}Y-DOTA-biotin in the locoregional treatment of peritoneal carcinomatosis and malignant glioma suggested that similar radionuclide therapy might be worth investigating as a partial replacement of external beam radiotherapy in breast cancer. We have developed IART® the Intra-operative Avidination for Radionuclide Therapy that relies on the avidin-biotin binding system. In fact, the “avidination” of the anatomical area of the tumor with native avidin, directly injected by the surgeon into and around the tumor bed, provides a target for the radiolabeled biotin intravenously (iv) injected one day later. In order to optimize the overall strategy, further efforts were needed to optimize the use of the labeled new biotin conjugate and to elucidate its chemical and biological properties. In the first 18 months of this CRP, the pre-clinical evaluation of this new reduced biotinamidohexylamine

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

Science.gov (United States)

Bray, Lane A.; Ryan, Jack L.

1998-01-01

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

One-dimensional unstable eigenfunction and manifold computations in delay differential equations

International Nuclear Information System (INIS)

Green, Kirk; Krauskopf, Bernd; Engelborghs, Koen

2004-01-01

In this paper we present a new numerical technique for computing the unstable eigenfunctions of a saddle periodic orbit in a delay differential equation. This is used to obtain the necessary starting data for an established algorithm for computing one-dimensional (1D) unstable manifolds of an associated saddle fixed point of a suitable Poincare map. To illustrate our method, we investigate an intermittent transition to chaos in a delay system describing a semiconductor laser subject to phase-conjugate feedback

Purification of SUMO conjugating enzymes and kinetic analysis of substrate conjugation

Science.gov (United States)

Yunus, Ali A.; Lima, Christopher D.

2009-01-01

SUMO conjugation to protein substrates requires the concerted action of a dedicated E2 ubiquitin conjugation enzyme (Ubc9) and associated E3 ligases. Although Ubc9 can directly recognize and modify substrate lysine residues that occur within a consensus site for SUMO modification, E3 ligases can redirect specificity and enhance conjugation rates during SUMO conjugation in vitro and in vivo. In this chapter, we will describe methods utilized to purify SUMO conjugating enzymes and model substrates which can be used for analysis of SUMO conjugation in vitro. We will also describe methods to extract kinetic parameters during E3-dependent or E3-independent substrate conjugation. PMID:19107417

Radionuclide trap

International Nuclear Information System (INIS)

McGuire, J.C.

1978-01-01

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

Radionuclide ventriculography in children with Duchenne muscular dystrophy

International Nuclear Information System (INIS)

Tian Jiahe

1992-01-01

The ventricular functions of 22 children with Duchenne disease(DD) were studied by radionuclide multi-gated ventriculography using in-vivo labeled 99m Tc-RBC and compared with those of 30 age-matched normal children, 20 congenital heart disease and 7 congestive cardiomyopathy. 21 parameters were evaluated, including RV and LV EF, systolic and diastolic functions and phase distribution, etc. It was found that the DD patients showed several specific cardiac functional alterations, i.e, slight but significant abnormality in both systolic and diastolic function, special phase delay at post-lateral segment of LV in 81.8% of the patients. It is concluded that (1) all DD patients have definite evidence of heart injury; (2) the injury is mainly on the left side of the heart, influencing entire cardiac cycle; (3) there is specific phase abnormality in DD patients; (4) the radionuclide ventriculography is of great value in monitoring of these cardiac functional changes

Experimental fracture healing: evaluation using radionuclide bone imaging: concise communication

International Nuclear Information System (INIS)

Gumerman, L.W.; Fogel, S.R.; Goodman, M.A.; Hanley, E.N. Jr.; Kappakas, G.S.; Rutkowski, R.; Levine, G.

1978-01-01

Radionuclide bone imaging was performed in a rabbit model to observe the course of fracture healing and to establish criteria for distinguishing nonunion and delayed healing from normal healing. Sequential gamma-camera images (with pinhole collimator) were collected and subjected to computer analysis. Five groups were established: (a) control--immobilization; (b) control--immobilization plus periosteal stripping; (c) simple fracture--osteotomy; (d) delayed union--osteotomy plus periosteal stripping; and (e) nonunion--osteotomy, periosteal stripping and polymethyl methacrylate interposed between fracture fragments. Histographic representation of absolute count rates along rabbit tibias followed a predictable pattern in the simple-fracture and delayed-union groups. They differed only in the time of appearance of phases. The non-union group demonstrated no recognizable sequential pattern. In this experimental model, serial bone scanning the quantitative data analysis has shown potential for indicating the course of healing in fractures and for serving as a guide to treatment

Radionuclide cisternography

International Nuclear Information System (INIS)

Song, H.H.

1980-01-01

The purpose of this thesis is to show that radionuclide cisternography makes an essential contribution to the investigation of cerebrospinal fluid (CSF) dynamics, especially for the investigation of hydrocephalus. The technical details of radionuclide cisternography are discussed, followed by a description of the normal and abnormal radionuclide cisternograms. The dynamics of CFS by means of radionuclide cisternography were examined in 188 patients in whom some kind of hydrocephalus was suspected. This study included findings of anomalies associated with hydrocephalus in a number of cases, such as nasal liquorrhea, hygromas, leptomeningeal or porencephalic cysts. The investigation substantiates the value of radionuclide cisternography in the diagnosis of disturbances of CSF flow. The retrograde flow of radiopharmaceutical into the ventricular system (ventricular reflux) is an abnormal phenomenon indicating the presence of communicating hydrocephalus. (Auth.)

New peptide receptor radionuclide therapy of invasive cancer cells: in vivo studies using 177Lu-DOTA-AE105 targeting uPAR in human colorectal cancer xenografts

DEFF Research Database (Denmark)

Persson, Morten; Rasmussen, Palle; Madsen, Jacob

2012-01-01

-of-concept for a theranostic approach as treatment modality in a human xenograft colorectal cancer model. MethodsA DOTA-conjugated 9-mer high affinity uPAR binding peptide (DOTA-AE105) was radiolabeled with 64Cu and 177Lu, for PET imaging and targeted radionuclide therapy study, respectively. Human uPAR-positive CRC HT-29...... for the first time the in vivo efficacy of an uPAR-targeted radionuclide therapeutic intervention on both tumor size and its content of uPAR expressing cells thus setting the stage for future translation into clinical use. © 2012 Elsevier Inc. All rights reserved....

Interventricular delay measurement using equilibrium radionuclide angiography before resynchronization therapy should be performed outside the area of segmental wall motion abnormalities

Energy Technology Data Exchange (ETDEWEB)

Courtehoux, Maxime [Service EFMP CHU Trousseau, Chambray les Tours (France); Zannad, Noura; Fauchier, Laurent; Babuty, Dominique [Service Cardiologie B CHU Trousseau, Tours (France); Eder, Veronique [Service EFMP CHU Trousseau, Chambray les Tours (France); EA3852 University Francois Rabelais, Tours (France)

2011-02-15

The aim of this study was to demonstrate that only mechanical dyssynchrony outside the area of segmental wall motion abnormalities (WMA) can be reduced by cardiac resynchronization therapy (CRT). Included in the study were 28 consecutive patients with nonischaemic cardiomyopathy selected for CRT. Equilibrium radionuclide angiography (ERNA) was carried out before and after implantation of a multisite pacemaker. Patients were separated into two groups depending on the presence or absence of segmental WMA. A reduction in QRS duration was observed in all patients after CRT. The interventricular delay (IVD) decreased significantly after CRT only in patients without WMA (homogeneous contraction, HG group; IVD 44 {+-} 11.4 vs. 17 {+-} 3.1 , p = 0.04). In contrast, no significant decrease was observed in patients with WMA (WMA group; IVD 51 {+-} 6 vs. 38 {+-} 6 , p NS). However, when dyssynchrony was considered outside the WMA area, a significant reduction in IVD was obtained, in the same range as in the HG group (IVD 32 {+-} 3 vs. 19 {+-} 3 , p = 0.04). In 9 of 15 patients (60%) with a reduction in IVD after CRT, the left ventricle ejection fraction (LVEF) increased by about +10%. In contrast, in 13 of 13 patients (100%) with no reduction in IVD, no modification of LVEF was obtained. In the presence of segmental WMA without significant delays outside the WMA area, no reduction in IVD was observed and LVEF did not increase (IVD 34 {+-} 5 before CRT vs. 37 {+-} 7 after CRT; LVEF 19 {+-} 4% before CRT vs. 22 {+-} 3% after CRT, p NS). ERNA can be used to predict good mechanical resynchronization (decrease in IVD) in patients after pacing. IVD has to be determined excluding the area of WMA in order to select patients who will show an increase in their left ventricle function after CRT. (orig.)

Speciation analysis of radionuclides

International Nuclear Information System (INIS)

Salbu, B.

2010-01-01

Full text: Naturally occurring and artificially produced radionuclides in the environment can be present in different physico-chemical forms (i. e. radionuclide species) varying in size (nominal molecular mass), charge properties and valence, oxidation state, structure and morphology, density, complexing ability etc. Low molecular mass (LMM) species are believed to be mobile and potentially bioavailable, while high molecular mass (HMM) species such as colloids, polymers, pseudocolloids and particles are considered inert. Due to time dependent transformation processes such as mobilization of radionuclide species from solid phases or interactions of mobile and reactive radionuclide species with components in soils and sediments, however, the original distribution of radionuclides deposited in ecosystems will change over time and influence the ecosystem behaviour. To assess the environmental impact from radionuclide contamination, information on radionuclide species deposited, interactions within affected ecosystems and the time-dependent distribution of radionuclide species influencing mobility and biological uptake is essential. The development of speciation techniques to characterize radionuclide species in waters, soils and sediments should therefore be essential for improving the prediction power of impact and risk assessment models. The present paper reviews fractionation techniques which should be utilised for radionuclide speciation purposes. (author)

Quantitative radionuclide angiocardiography

International Nuclear Information System (INIS)

Scholz, P.M.; Rerych, S.K.; Moran, J.F.; Newman, G.E.; Douglas, J.M.; Sabiston, D.C. Jr.; Jones, R.H.

1980-01-01

This study introduces a new method for calculating actual left ventricular volumes and cardiac output from data recorded during a single transit of a radionuclide bolus through the heart, and describes in detail current radionuclide angiocardiography methodology. A group of 64 healthy adults with a wide age range were studied to define the normal range of hemodynamic parameters determined by the technique. Radionuclide angiocardiograms were performed in patients undergoing cardiac catherization to validate the measurements. In 33 patients studied by both techniques on the same day, a close correlation was documented for measurement of ejection fraction and end-diastolic volume. To validate the method of volumetric cardiac output calcuation, 33 simultaneous radionuclide and indocyanine green dye determinations of cardiac output were performed in 18 normal young adults. These independent comparisons of radionuclide measurements with two separate methods document that initial transit radionuclide angiocardiography accurately assesses left ventricular function

Delayed airway stenosis after radiotherapy for head and neck cancer

Energy Technology Data Exchange (ETDEWEB)

Yuta, Atsushi; Tatematsu, Masanori; Ishinaga, Hajime; Harada, Teruhiko; Majima, Yuichi [Mie Univ., Tsu (Japan). School of Medicine

2002-03-01

Seven cases of delayed airway stenosis after radiotherapy for early staged head and neck cancers during 1989 and 1999 were evaluated (aged 54-77 yrs, 6 male and a female). The cases included five glottic laryngeal cancers (T1a, T1b, and three T2), a subglottic laryngeal cancer, and an unknown origin, but strongly suspected laryngeal cancer, with neck metastasis. Radio injury was found from 3 months to 47 months after radiotherapy. {sup 60}Co for radiotherapy was used in all seven cases, although {sup 60}Co radionuclide was changed to Liniac in 1997. The total dose was 60 Gy for 3 cases, and 70 Gy for 4 cases. Tracheostomy was performed in 3 cases due to bilateral vocal cord impairment. Background, treatment, and response to radiotherapy were compared to those of 90 patients of a control group with early staged laryngeal cancer who did not fail radiation injury during the same period. As a result, radionuclide ({sup 60}Co), total dose, cervical surgery, antiinflammatory drugs, laryngeal edema during radiotherapy were risk factors. The intensity and the period of mucositis by radiotherapy was important for indicating delayed airway stenosis. (author)

Delayed airway stenosis after radiotherapy for head and neck cancer

International Nuclear Information System (INIS)

Yuta, Atsushi; Tatematsu, Masanori; Ishinaga, Hajime; Harada, Teruhiko; Majima, Yuichi

2002-01-01

Seven cases of delayed airway stenosis after radiotherapy for early staged head and neck cancers during 1989 and 1999 were evaluated (aged 54-77 yrs, 6 male and a female). The cases included five glottic laryngeal cancers (T1a, T1b, and three T2), a subglottic laryngeal cancer, and an unknown origin, but strongly suspected laryngeal cancer, with neck metastasis. Radio injury was found from 3 months to 47 months after radiotherapy. 60 Co for radiotherapy was used in all seven cases, although 60 Co radionuclide was changed to Liniac in 1997. The total dose was 60 Gy for 3 cases, and 70 Gy for 4 cases. Tracheostomy was performed in 3 cases due to bilateral vocal cord impairment. Background, treatment, and response to radiotherapy were compared to those of 90 patients of a control group with early staged laryngeal cancer who did not fail radiation injury during the same period. As a result, radionuclide ( 60 Co), total dose, cervical surgery, antiinflammatory drugs, laryngeal edema during radiotherapy were risk factors. The intensity and the period of mucositis by radiotherapy was important for indicating delayed airway stenosis. (author)

Radionuclide Imaging of Musculoskeletal Injuries in Athletes with Negative Radiographs.

Science.gov (United States)

Nagle, C E; Freitas, J E

1987-06-01

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

Radionuclide administration to nursing mothers: mathematically derived guidelines

International Nuclear Information System (INIS)

Romney, B.M.; Nickoloff, E.L.; Esser, P.D.; Alderson, P.O.

1986-01-01

We determined a formula to establish objective guidelines for the administration of radionuclides to nursing mothers. The formula is based on the maximum permissible dose to the infant's critical organ, serial measurements of breast milk activity, milk volume, and dose to the critical organ per microcurie in milk. Using worst-case assumptions, we believe that cessation of nursing for 24 hours after administration of technetium labeled radiopharmaceuticals is sufficient for safety. Longer-lived agents require greater delays. Iodine-123 radiopharmaceuticals are preferable to iodine-131 agents and should always be used when studying the unblocked thyroid

Novel Hyaluronic Acid Conjugates for Dual Nuclear Imaging and Therapy in CD44-Expressing Tumors in Mice In Vivo

Science.gov (United States)

Dubey, Ravindra Dhar; Klippstein, Rebecca; Wang, Julie Tzu-Wen; Hodgins, Naomi; Mei, Kuo-Ching; Sosabowski, Jane; Hider, Robert C.; Abbate, Vincenzo; Gupta, Prem N.; Al-Jamal, Khuloud T.

2017-01-01

Hyaluronic acid, a natural CD44 receptor ligand, has attracted attention in the past years as a macromolecular delivery of anticancer agents to cancer. At the same time, the clinical applications of Gemcitabine (Gem) have been hindered by its short biological half-life, high dose and development of drug resistance. This work reports the synthesis of a hyaluronic acid (HA) conjugate for nuclear imaging, and in vivo Gem delivery to CD44-expressing solid tumors in mice. HA was individually conjugated, via amide coupling, to Gem (HA-Gem), 4'-(aminomethyl)fluorescein hydrochloride (HA-4'-AMF) or tris(hydroxypyridinone) amine (HA-THP) for cancer therapy, in vitro tracking or single photon emission computed tomography/computed tomography (SPECT/CT) imaging, respectively. Gem conjugation to HA was directly confirmed by nuclear magnetic resonance (1H NMR), gel permeation chromatography (GPC) and UV-visible spectrometry, or indirectly by a nucleoside transporter inhibition study. Gem conjugation to HA improved its plasma stability, reduced blood hemolysis and resulted in delayed cytotoxicity in vitro. Uptake inhibition studies in colon CT26 and pancreatic PANC-1 cells, by flow cytometry, revealed that uptake of fluorescent HA conjugate is CD44 receptor and macropinocytosis-dependent. Gamma scintigraphy and SPECT/CT imaging confirmed the relatively prolonged blood circulation profile and uptake in CT26 (1.5 % ID/gm) and PANC-1 (1 % ID/gm) subcutaneous tumors at 24 h after intravenous injection in mice. Four injections of HA-Gem at ~15 mg/kg, over a 28-day period, resulted in significant delay in CT26 tumor growth and prolonged mice survival compared to the free drug. This study reports for the first time dual nuclear imaging and drug delivery (Gem) of HA conjugates to solid tumors in mice. The conjugates show great potential in targeting, imaging and killing of CD44-over expressing cells in vivo. This work is likely to open new avenues for the application of HA

Synthesis of DOTA-conjugated multimeric [Tyr3]octreotide peptides via a combination of Cu(I)-catalyzed "click" cycloaddition and thio acid/sulfonyl azide "sulfo-click" amidation and their in vivo evaluation.

NARCIS (Netherlands)

Yim, C.B.; Dijkgraaf, I.; Merkx, R.; Versluis, C.; Eek, A.; Mulder, G.E.; Rijkers, D.T.; Boerman, O.C.; Liskamp, R.M.

2010-01-01

Herein, we describe the design, synthesis, and biological evaluation of a series of DOTA-conjugated monomeric, dimeric, and tetrameric [Tyr(3)]octreotide-based analogues as a tool for tumor imaging and/or radionuclide therapy. These compounds were synthesized using a Cu(I)-catalyzed 1,3-dipolar

Waste/Rock Interactions Technology Program: the status of radionuclide sorption-desorption studies performed by the WRIT program

International Nuclear Information System (INIS)

Serne, R.J.; Relyea, J.F.

1982-04-01

The most credible means for radionuclides disposed as solid wastes in deep-geologic repositories to reach the biosphere is through dissolution of the solid waste and subsequent radionuclide transport by circulating ground water. Thus safety assessment activities must consider the physicochemical interactions between radionculides present in ground water with package components, rocks and sediments since these processes can significantly delay or constrain the mass transport of radionuclides in comparison to ground-water movement. This paper focuses on interactions between dissolved radiouclides in ground water and rocks and sediments away from the near-field repository. The primary mechanism discussed is adsorption-desorption, which has been studied using two approaches. Empirical studies of adsorption-desorption rely on distribution coefficient measurements while mechanism studies strive to identify, differentiate and quantify the processes that control nuclide retardation

Radiolabeled, Antibody-Conjugated Manganese Oxide Nanoparticles for Tumor Vasculature Targeted Positron Emission Tomography and Magnetic Resonance Imaging.

Science.gov (United States)

Zhan, Yonghua; Shi, Sixiang; Ehlerding, Emily B; Graves, Stephen A; Goel, Shreya; Engle, Jonathan W; Liang, Jimin; Tian, Jie; Cai, Weibo

2017-11-08

Manganese oxide nanoparticles (Mn 3 O 4 NPs) have attracted a great deal of attention in the field of biomedical imaging because of their ability to create an enhanced imaging signal in MRI as novel potent T 1 contrast agents. In this study, we present tumor vasculature-targeted imaging in mice using Mn 3 O 4 NPs through conjugation to the anti-CD105 antibody TRC105 and radionuclide copper-64 ( 64 Cu, t 1/2 : 12.7 h). The Mn 3 O 4 conjugated NPs, 64 Cu-NOTA-Mn 3 O 4 @PEG-TRC105, exhibited sufficient stability in vitro and in vivo. Serial positron emission tomography (PET) and magnetic resonance imaging (MRI) studies evaluated the pharmacokinetics and demonstrated targeting of 64 Cu-NOTA-Mn 3 O 4 @PEG-TRC105 to 4T1 murine breast tumors in vivo, compared to 64 Cu-NOTA-Mn 3 O 4 @PEG. The specificity of 64 Cu-NOTA-Mn 3 O 4 @PEG-TRC105 for the vascular marker CD105 was confirmed through in vivo, in vitro, and ex vivo experiments. Since Mn 3 O 4 conjugated NPs exhibited desirable properties for T 1 enhanced imaging and low toxicity, the tumor-specific Mn 3 O 4 conjugated NPs reported in this study may serve as promising multifunctional nanoplatforms for precise cancer imaging and diagnosis.

Radiolabeled Cetuximab Conjugates for EGFR Targeted Cancer Diagnostics and Therapy

Directory of Open Access Journals (Sweden)

Wiebke Sihver

2014-03-01

Full Text Available The epidermal growth factor receptor (EGFR has evolved over years into a main molecular target for the treatment of different cancer entities. In this regard, the anti-EGFR antibody cetuximab has been approved alone or in combination with: (a chemotherapy for treatment of colorectal and head and neck squamous cell carcinoma and (b with external radiotherapy for treatment of head and neck squamous cell carcinoma. The conjugation of radionuclides to cetuximab in combination with the specific targeting properties of this antibody might increase its therapeutic efficiency. This review article gives an overview of the preclinical studies that have been performed with radiolabeled cetuximab for imaging and/or treatment of different tumor models. A particularly promising approach seems to be the treatment with therapeutic radionuclide-labeled cetuximab in combination with external radiotherapy. Present data support an important impact of the tumor micromilieu on treatment response that needs to be further validated in patients. Another important challenge is the reduction of nonspecific uptake of the radioactive substance in metabolic organs like liver and radiosensitive organs like bone marrow and kidneys. Overall, the integration of diagnosis, treatment and monitoring as a theranostic approach appears to be a promising strategy for improvement of individualized cancer treatment.

Radionuclide fixation mechanisms in rocks

International Nuclear Information System (INIS)

Nakashima, S.

1991-01-01

In the safety evaluation of the radioactive waste disposal in geological environment, the mass balance equation for radionuclide migration is given. The sorption of radionuclides by geological formations is conventionally represented by the retardation of the radionuclides as compared with water movement. In order to quantify the sorption of radionuclides by rocks and sediments, the distribution ratio is used. In order to study quantitatively the long term behavior of waste radionuclides in geological environment, besides the distribution ratio concept in short term, slower radionuclide retention reaction involving mineral transformation should be considered. The development of microspectroscopic method for long term reaction path modeling, the behavior of iron during granite and water interaction, the reduction precipitation of radionuclides, radionuclide migration pathways, and the representative scheme of radionuclide migration and fixation in rocks are discussed. (K.I.)

Biological toxicity of intracellular radionuclide decay. Part of a coordinated programme on radiation biology of Auger emitters and their therapeutic applications

International Nuclear Information System (INIS)

Hofer, K.G.

1980-06-01

Internal radiotherapy should be performed with short-lived radionuclides which emit high LET radiation and short ranged radiation, and accumulated within cancers. Based on these considerations, several radionuclides (tritium, copper-64, gallium-67, iodine-123, iodine 125, iodine-131 and astatine-211) were chosen and their toxicity was assessed using cell division in mammalian cultured cells as a criterion. It was apparent that the toxic effects obtained with 125 I greatly exceeded those observed in cells treated with any other radionuclides. The possible hypotheses to explain the excessive radiosensitivity of 125 I were discussed in relation to microdosimetry calculation. It was also found that the division delay induced by radionuclide decay is primarily due to damage to the cell nucleus but not to the plasma membrane. The key problem remains the development of agents which can serve as carriers for radionuclide accumulation within tumors. Although several promising approaches (Synkavit, tamoxifen, iododeoxyuridine, antibodies, liposomes) were investigated, only 125 I-labelled Synkavit would be desirable for clinical application

Marine biogeochemistry of radionuclides

International Nuclear Information System (INIS)

Fowler, S.W.

1997-01-01

Radionuclides entering the ocean from runoff, fallout, or deliberate release rapidly become involved in marine biogeochemical cycles. Sources, sinks and transport of radionuclides and analogue elements are discussed with emphasis placed on how these elements interact with marine organisms. Water, food and sediments are the source terms from which marine biota acquire radionuclides. Uptake from water occurs by surface adsorption, absorption across body surfaces, or a combination of both. Radionuclides ingested with food are either assimilated into tissue or excreted. The relative importance of the food and water pathway in uptake varies with the radionuclide and the conditions under which exposure occurs. Evidence suggests that, compared to the water and food pathways, bioavailability of sediment-bound radionuclides is low. Bioaccumulation processes are controlled by many environmental and intrinsic factors including exposure time, physical-chemical form of the radionuclide, salinity, temperature, competitive effects with other elements, organism size, physiology, life cycle and feeding habits. Once accumulated, radionuclides are transported actively by vertical and horizontal movements of organisms and passively by release of biogenic products, e.g., soluble excreta, feces, molts and eggs. Through feeding activities, particles containing radionuclides are ''packaged'' into larger aggregates which are redistributed upon release. Most radionuclides are not irreversibly bound to such particles but are remineralized as they sink and/or decompose. In the pelagic zones, sinking aggregates can further scavenge particle-reactive elements thus removing them from the surface layers and transporting them to depth. Evidence from both radiotracer experiments and in situ sediment trap studies is presented which illustrates the importance of biological scavenging in controlling the distribution of radionuclides in the water column. (author)

Radionuclide methods of identifying patients who may require coronary artery bypass surgery

International Nuclear Information System (INIS)

Beller, G.A.; Gibson, R.S.; Watson, D.D.

1985-01-01

Myocardial thallium-201 ( 201 Tl) scintigraphy or radionuclide angiography performed in conjunction with exercise stress testing can provide clinically useful information regarding the functional significance of underlying coronary artery stenoses in patients with known or suspected coronary artery disease. Knowledge of type, location, and extent of myocardial 201 Tl perfusion abnormalities or the severity of exercise-induced global and regional dysfunction has prognostic value. Risk stratification can be undertaken with either radionuclide technique by consideration of the magnitude of the ischemic response and may assist in the selection of patients for coronary artery bypass graft surgery (CABG). In patients with coronary artery disease, delayed 201 Tl redistribution observed on exercise or dipyridamole 201 Tl scintigraphy, particularly when present in multiple vascular regions and associated with increased lung 201 Tl uptake, has been shown to be predictive of an adverse outcome, whereas patients with chest pain and a normal exercise 201 Tl scintigram have a good prognosis with medical treatment. Similarly, a marked fall in the radionuclide ejection fraction from rest to exercise has been found to correlate with high-risk anatomic disease. Another important application of radionuclide imaging in patients being considered for CABG (particularly those with a depressed resting left ventricular ejection fraction) is the determination of myocardial viability and potential for improved blood flow and enhanced regional function after revascularization. 69 references

Delayed biological effects of incorporated sulfur-35 in combination with IOS-4876

International Nuclear Information System (INIS)

Rusanova, O.V.

1990-01-01

Comparative evaluation of some delayed effects of sulfur-35 single administration to mongree white rats males is carried out; modifying effect of IOS-4876 preparation on biological efficiency of incorporated sulfur-35 is also evaluated. Different radionuclide doses demonstrated identical tumor effect exceeding by 2.2-3 times the level of spontaneous tumors. Sulfur-35 incorporated in quantities of 185 and 925 kBq/g causes proved increase in rats death level during the first two years of observation. IOS-4876 preparation leads to certain decrease in the level of delayed biological effects due to internal irradiation. 11 refs

The use of radiocobalt as a label improves imaging of EGFR using DOTA-conjugated Affibody molecule.

Science.gov (United States)

Garousi, Javad; Andersson, Ken G; Dam, Johan H; Olsen, Birgitte B; Mitran, Bogdan; Orlova, Anna; Buijs, Jos; Ståhl, Stefan; Löfblom, John; Thisgaard, Helge; Tolmachev, Vladimir

2017-07-20

Several anti-cancer therapies target the epidermal growth factor receptor (EGFR). Radionuclide imaging of EGFR expression in tumours may aid in selection of optimal cancer therapy. The 111 In-labelled DOTA-conjugated Z EGFR:2377 Affibody molecule was successfully used for imaging of EGFR-expressing xenografts in mice. An optimal combination of radionuclide, chelator and targeting protein may further improve the contrast of radionuclide imaging. The aim of this study was to evaluate the targeting properties of radiocobalt-labelled DOTA-Z EGFR:2377 . DOTA-Z EGFR:2377 was labelled with 57 Co (T 1/2  = 271.8 d), 55 Co (T 1/2  = 17.5 h), and, for comparison, with the positron-emitting radionuclide 68 Ga (T 1/2  = 67.6 min) with preserved specificity of binding to EGFR-expressing A431 cells. The long-lived cobalt radioisotope 57 Co was used in animal studies. Both 57 Co-DOTA-Z EGFR:2377 and 68 Ga-DOTA-Z EGFR:2377 demonstrated EGFR-specific accumulation in A431 xenografts and EGFR-expressing tissues in mice. Tumour-to-organ ratios for the radiocobalt-labelled DOTA-Z EGFR:2377 were significantly higher than for the gallium-labelled counterpart already at 3 h after injection. Importantly, 57 Co-DOTA-Z EGFR:2377 demonstrated a tumour-to-liver ratio of 3, which is 7-fold higher than the tumour-to-liver ratio for 68 Ga-DOTA-Z EGFR:2377 . The results of this study suggest that the positron-emitting cobalt isotope 55 Co would be an optimal label for DOTA-Z EGFR:2377 and further development should concentrate on this radionuclide as a label.

TRING: a computer program for calculating radionuclide transport in groundwater

International Nuclear Information System (INIS)

Maul, P.R.

1984-12-01

The computer program TRING is described which enables the transport of radionuclides in groundwater to be calculated for use in long term radiological assessments using methods described previously. Examples of the areas of application of the program are activity transport in groundwater associated with accidental spillage or leakage of activity, the shutdown of reactors subject to delayed decommissioning, shallow land burial of intermediate level waste and geologic disposal of high level waste. Some examples of the use of the program are given, together with full details to enable users to run the program. (author)

Risk governance on radionuclide contamination in food in Japan

International Nuclear Information System (INIS)

Sekizawa, Jun

2012-01-01

A large scale nuclear power plant accident happened after the great earthquake in Fukushima in March 2011. There was several critical mismanagement of the accident which resulted in the radio-nuclides release in the environment. Furthermore the information delay and the lack in delivery of clear and comprehensible explanation of the risk have been causing huge anxieties and worries among people living near to the site, and also people in the nation. Risk assessment appeared not to meet appropriately requests of risk management authorities and also people. Author has been trying to straighten the large amounts of data on radionuclide contamination in foods so as for people to easily understand the real situation with succinct messages explaining risk and to take appropriate actions in facing the risk. Appropriate responses and coordination among the risk managing authorities are indispensable especially in this kind of huge accident which may entail vast scale and long lasting risk and a new paradigm of the food safety governance is required in Japan. (author)

Radionuclide generators

International Nuclear Information System (INIS)

Lambrecht, R.M.; Wollongong Univ.; Tomiyoshi, K.; Sekine, T.

1997-01-01

The present status and future directions of research and development on radionuclide generator technology are reported. The recent interest to develop double-neutron capture reactions for production of in vivo generators; neutron rich nuclides for radio-immunotherapeutic pharmaceuticals: and advances with ultra-short lived generators is highlighted. Emphasis is focused on: production of the parent radionuclide; the selection and the evaluation of support materials and eluents with respect to the resultant radiochemical yield of the daughter, and the breakthrough of the radionuclide parent: and, the uses of radionuclide generators in radiopharmaceutical chemistry, biomedical and industrial applications. The 62 Zn → 62 Cu, 66 Ni → 66 Cu, 103m Rh → 103 Rh, 188 W → 188 Re and the 225 Ac → 221 Fr → 213 Bi generators are predicted to be emphasized for future development. Coverage of the 99 Mo → 99m Tc generator was excluded, as it the subject of another review. The literature search ended June, 1996. (orig.)

Renography and indirect radionuclide cystography; Nierenfunktionsszintigrafie und indirekte Refluxpruefung

Energy Technology Data Exchange (ETDEWEB)

Franzius, C. [Universitaetsklinikum Muenster (Germany). Klinik und Poliklinik fuer Nuklearmedizin; MR-, Nuklearmedizin- und PET/CT-Zentrum Bremen-Mitte (Germany); Hahn, Klaus [Klink und Poliklinik fuer Nuklearmedizin Klinikum der Ludwig-Maximilians-Univ. Muenchen (Germany)

2010-09-15

Renal scintigraphy is one of the most common performed nuclear medicine procedures mainly in childhood. This review article describes in detail indications, preparation, data acquisition, data analysis and interpretation of renography using {sup 99m}Tc-MAG3 including indirect reflux study (radionuclide cystography) and of static renal scintigraphy using {sup 99m}Tc-DMSA. The current controversies in interpretation were considered, especially the interpretation of a reduced or delayed drainage. Pitfalls in performance and analysis and the avoidance were addressed. Renography is a routine examination that allows a visual and quantitative evaluation of various aspects of renal function. (orig.)

Radiolabeled Cetuximab Conjugates for EGFR Targeted Cancer Diagnostics and Therapy †

Science.gov (United States)

Sihver, Wiebke; Pietzsch, Jens; Krause, Mechthild; Baumann, Michael; Steinbach, Jörg; Pietzsch, Hans-Jürgen

2014-01-01

The epidermal growth factor receptor (EGFR) has evolved over years into a main molecular target for the treatment of different cancer entities. In this regard, the anti-EGFR antibody cetuximab has been approved alone or in combination with: (a) chemotherapy for treatment of colorectal and head and neck squamous cell carcinoma and (b) with external radiotherapy for treatment of head and neck squamous cell carcinoma. The conjugation of radionuclides to cetuximab in combination with the specific targeting properties of this antibody might increase its therapeutic efficiency. This review article gives an overview of the preclinical studies that have been performed with radiolabeled cetuximab for imaging and/or treatment of different tumor models. A particularly promising approach seems to be the treatment with therapeutic radionuclide-labeled cetuximab in combination with external radiotherapy. Present data support an important impact of the tumor micromilieu on treatment response that needs to be further validated in patients. Another important challenge is the reduction of nonspecific uptake of the radioactive substance in metabolic organs like liver and radiosensitive organs like bone marrow and kidneys. Overall, the integration of diagnosis, treatment and monitoring as a theranostic approach appears to be a promising strategy for improvement of individualized cancer treatment. PMID:24603603

Radionuclides in terrestrial ecosystems

International Nuclear Information System (INIS)

Allen, S.E.; Horrill, A.D.; Howard, B.J.; Lowe, V.P.W.; Parkinson, J.A.

1983-07-01

The subject is discussed under the headings: concentration and spatial distribution of radionuclides in grazed and ungrazed saltmarshes; incorporation of radionuclides by sheep grazing on an estuarine saltmarsh; inland transfer of radionuclides by birds feeding in the estuaries and saltmarshes at Ravenglass; radionuclides in contrasting types of coastal pastures and taken up by individual plant species found in west Cumbria; procedures developed and used for the measurement of alpha and gamma emitters in environmental materials. (U.K.)

Radionuclide data

International Nuclear Information System (INIS)

Anon.

1992-01-01

Chapter 8 presents tables on selected alpha, beta, gamma and x-ray emitters by increasing energy; information on specific activity for selected radionuclides; naturally occurring radionuclides; the natural decay series; and the artificially produced neptunium series. A table of alpha emitters is listed by increasing atomic number and by energy. The table of β emitters presented is useful in identifying β emitters whose energies and possibly half-lives have been determined by standard laboratory techniques. It is also a handy guide to β-emitting isotopes for applications requiring specific half-lives and/or energies. Gamma rays for radionuclides of importance to radiological assessments and radiation protection are listed by increasing energy. The energies and branching ratios are important for radionuclide determinations with gamma spectrometry detectors. This section also presents a table of x-ray energies which are useful for radiochemical analyses. A number of nuclides emit x-rays as part of their decay scheme. These x-rays may be counted with Ar proportional counters, Ge planar or n-type Ge co-axial detectors, or thin crystal NaI(T1) scintillation counters. In both cases, spectral measurements can be made and both qualitative and quantitative information obtained on the sample. Nuclear decay data (energy and probability by radiation type) for more than one hundred radionuclides that are important to health physicists are presented in a schematic manner

Evaluation of iodovinyl antibody conjugates: Comparison with a p-iodobenzoyl conjugate and direct radioiodination

International Nuclear Information System (INIS)

Hadley, S.W.; Wilbur, D.S.

1990-01-01

The preparations and conjugations of 2,3,5,6-tetrafluorophenyl 5-[125I/131I]iodo-4-pentenoate (7a) and 2,3,5,6-tetrafluorophenyl 3,3-dimethyl-5-[125I/131I]iodo-4-pentenoate (7b) to monoclonal antibodies are reported. Reagents 7a and 7b were prepared in high radiochemical yield by iododestannylation of their corresponding 5-tri-n-butylstannyl precursors. Radioiodinated antibody conjugates were prepared by reaction of 7a or 7b with the protein at basic pH. Evaluation of these conjugates by several in vitro procedures demonstrated that the radiolabel was attached to the antibody in a stable manner and that the conjugates maintained immunoreactivity. Comparative dual-isotope biodistribution studies of a monoclonal antibody Fab fragment conjugate of 7a and 7b with the same Fab fragment labeled with N-succinimidyl p-[131I]iodobenzoate (PIB, p-iodobenzoate, 2) or directly radioiodinated have been carried out in tumor-bearing nude mice. Coinjection of the Fab conjugate of 7a with the Fab conjugate of 2 demonstrated that the biodistributions were similar in most organs, except the neck tissue (thyroid-containing) and the stomach, which contained substantially increased levels of the 7a label. Coinjection of the Fab conjugate of 7a with the Fab fragment radioiodinated by using the chloramine-T method demonstrated that the biodistributions were remarkably similar, suggesting roughly equivalent in vivo deiodination of these labeled antibody fragments. Coinjection of the Fab conjugate of 7a with the Fab conjugate of 7b indicated that there was ∼ a 2-fold reduction in the amount of in vivo deiodination of the 7b conjugate as compared to the 7a conjugate

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

Energy Technology Data Exchange (ETDEWEB)

Rakovec, P.; Kranjec, I.; Fettich, J.J.; Jakopin, J.; Fidler, V.; Turk, J.

1985-01-01

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

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

International Nuclear Information System (INIS)

Rakovec, P.; Kranjec, I.; Fettich, J.J.; Jakopin, J.; Fidler, V.; Turk, J.

1985-01-01

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

Radionuclide generators

International Nuclear Information System (INIS)

Lambrecht, R.M.

1983-01-01

The status of radionuclide generators for chemical research and applications related to the life sciences and biomedical research are reviewed. Emphasis is placed upon convenient, efficient and rapid separation of short-lived daughter radionuclides in a chemical form suitable for use without further chemical manipulation. The focus is on the production of the parent, the radiochemistry associated with processing the parent and daughter, the selection and the characteristic separation methods, and yields. Quality control considerations are briefly noted. The scope of this review includes selected references to applications of radionuclide generators in radiopharmaceutical chemistry, and the life sciences, particularly in diagnostic and therapeutic medicine. The 99 Mo-sup(99m)Tc generator was excluded. 202 references are cited. (orig.)

Co-conjugation vis-à-vis individual conjugation of α-amylase and glucoamylase for hydrolysis of starch.

Science.gov (United States)

Jadhav, Swati B; Singhal, Rekha S

2013-10-15

Two enzymes, α-amylase and glucoamylase have been individually and co-conjugated to pectin by covalent binding. Both the enzyme systems showed better thermal and pH stability over the free enzyme system with the complete retention of original activities. Mixture of individually conjugated enzymes showed lower inactivation rate constant with longer half life than the co-conjugated enzyme system. Individually conjugated enzymes showed an increase of 56.48 kJ/mole and 38.22 kJ/mole in activation energy for denaturation than the free enzymes and co-conjugated enzymes, respectively. Km as well as Vmax of individually and co-conjugated enzymes was found to be higher than the free enzymes. SDS-polyacrylamide gel electrophoresis confirmed the formation of conjugate and co-conjugate as evident by increased molecular weight. Both the enzyme systems were used for starch hydrolysis where individually conjugated enzymes showed highest release of glucose at 60 °C and pH 5.0 as compared to free and co-conjugated enzyme. Copyright © 2013 Elsevier Ltd. All rights reserved.

ELF/VLF wave propagation at subauroral latitudes: Conjugate observation between the ground and Van Allen Probes

Czech Academy of Sciences Publication Activity Database

Martinez‐Calderon, C.; Shiokawa, K.; Miyoshi, Y.; Keika, K.; Ozaki, M.; Schofield, I.; Connors, M.; Kletzing, C.; Hanzelka, Miroslav; Santolík, Ondřej; Kurth, W. S.

2016-01-01

Roč. 121, č. 6 (2016), s. 5384-5393 ISSN 2169-9380 R&D Projects: GA ČR(CZ) GA14-31899S Institutional support: RVO:68378289 Keywords : QP * conjugate event * VLF/ELF * propagation * time delay * ray tracing Subject RIV: BL - Plasma and Gas Discharge Physics Impact factor: 2.733, year: 2016 http://onlinelibrary.wiley.com/doi/10.1002/2015JA022264/full

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

Science.gov (United States)

Widel, M

2017-01-01

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

Radionuclide cardiography in medical practice

International Nuclear Information System (INIS)

Strangfeld, D.; Mohnike, W.; Schmidt, J.; Heine, H.; Correns, H.J.

1986-01-01

This publication is a compendium on all aspects of radionuclide diagnostics concerning cardiovascular system diseases. Starting with introductory remarks on the control of cardiovascular diseases the contribution of radionuclide cardiology to functional cardiovascular diagnostics as well as pathophysiological and pathobiochemical aspects of radiocardiography are outlined. Radiopharmaceuticals used in radiocardiography, physical and technical problems in application of radionuclides and their measuring techniques are discussed. In individual chapters radionuclide ventriculography, myocardial scintiscanning, circulatory diagnostics, radionuclide diagnostics of arterial hypertension, of thrombosis and in vitro diagnostics of thrombophilia are treated in the framework of clinical medicine

Metabolism of radionuclides in domestic animals

International Nuclear Information System (INIS)

Wirth, E.; Leising, C.

1986-01-01

The reactor accident at Chernobyl has shown that shortly after the contamination of the environment radionuclides can be found in animal products. The main contamination pathways of domestic animas are: uptake of radionuclides by foodstuffs; uptake of radionuclides by contaminated drinking water; uptake of radionuclides by inhalation; uptake of radionuclides through skin; uptake of radionuclides by ingestion of soil particles. Generally the uptake of radionuclides by food is the dominant exposure pathway. In rare cases the inhalation of radionuclides or the uptake by drinking water may be of importance. The metabolism of incorporated radionuclides is comparable to the respective metabolism of essential mass or trace elements or heavy metals. Radioisotopes of essential elements are for instance iron 55, manganese 54, cobalt 58 and cobalt 60. Other elements are typical antagonists to essential elements, e.g. strontium 90 is an antagonist to calcium or cesium 137 to potassium. Lead 210 and plutonium 239 behave similarly as heavy metals. Generally the knowledge of the metabolism of trace and mass elements, of antagonistic and synergistic elements and heavy metals can be applied to these radionuclides

Radionuclide scanning

International Nuclear Information System (INIS)

Shapiro, B.

1986-01-01

Radionuclide scanning is the production of images of normal and diseased tissues and organs by means of the gamma-ray emissions from radiopharmaceutical agents having specific distributions in the body. The gamma rays are detected at the body surface by a variety of instruments that convert the invisible rays into visible patterns representing the distribution of the radionuclide in the body. The patterns, or images, obtained can be interpreted to provide or to aid diagnoses, to follow the course of disease, and to monitor the management of various illnesses. Scanning is a sensitive technique, but its specificity may be low when interpreted alone. To be used most successfully, radionuclide scanning must be interpreted in conjunction with other techniques, such as bone radiographs with bone scans, chest radiographs with lung scans, and ultrasonic studies with thyroid scans. Interpretation is also enhanced by providing pertinent clinical information because the distribution of radiopharmaceutical agents can be altered by drugs and by various procedures besides physiologic and pathologic conditions. Discussion of the patient with the radionuclide scanning specialist prior to the study and review of the results with that specialist after the study are beneficial

Drift-Scale Radionuclide Transport

International Nuclear Information System (INIS)

Houseworth, J.

2004-01-01

The purpose of this model report is to document the drift scale radionuclide transport model, taking into account the effects of emplacement drifts on flow and transport in the vicinity of the drift, which are not captured in the mountain-scale unsaturated zone (UZ) flow and transport models ''UZ Flow Models and Submodels'' (BSC 2004 [DIRS 169861]), ''Radionuclide Transport Models Under Ambient Conditions'' (BSC 2004 [DIRS 164500]), and ''Particle Tracking Model and Abstraction of Transport Process'' (BSC 2004 [DIRS 170041]). The drift scale radionuclide transport model is intended to be used as an alternative model for comparison with the engineered barrier system (EBS) radionuclide transport model ''EBS Radionuclide Transport Abstraction'' (BSC 2004 [DIRS 169868]). For that purpose, two alternative models have been developed for drift-scale radionuclide transport. One of the alternative models is a dual continuum flow and transport model called the drift shadow model. The effects of variations in the flow field and fracture-matrix interaction in the vicinity of a waste emplacement drift are investigated through sensitivity studies using the drift shadow model (Houseworth et al. 2003 [DIRS 164394]). In this model, the flow is significantly perturbed (reduced) beneath the waste emplacement drifts. However, comparisons of transport in this perturbed flow field with transport in an unperturbed flow field show similar results if the transport is initiated in the rock matrix. This has led to a second alternative model, called the fracture-matrix partitioning model, that focuses on the partitioning of radionuclide transport between the fractures and matrix upon exiting the waste emplacement drift. The fracture-matrix partitioning model computes the partitioning, between fractures and matrix, of diffusive radionuclide transport from the invert (for drifts without seepage) into the rock water. The invert is the structure constructed in a drift to provide the floor of the

Chapter 2. Radionuclides in the biosphere

International Nuclear Information System (INIS)

Toelgyessy, J.; Harangozo, M.

2000-01-01

This is a chapter of textbook of radioecology for university students. In this chapter authors deal with role of radionuclides in the biosphere. Chapter consists of next parts: (1) Natural radionuclides in biosphere; (2) Man-made radionuclides in the biosphere; (3) Ecologically important radionuclides; (4) Natural background; (5) Radiotoxicity and (6) Paths of transfer of radionuclides from the source to human

Studies on influence of biological factors on concentration of radionuclides

International Nuclear Information System (INIS)

Anon.

1974-01-01

Biological factors influencing the concentration of radionuclides were studied from the points of uptake through digestive tract, food as pathways, and metabolic activities. The uptake of radionuclides by marine fishes through digestive tract was determined by whole body counter. 137 Cs, 65 Zn, 131 I, 54 Mn, 60 Co, 85 Sr, and 144 Ce were used as tracers and was given with solid feed. The feed given was excreated 24 to 48 hours later in small of middle sized fishes, and 20 to 48 hours later in large sized fishes. The uptake rate of 137 Cs and 65 Zn was high absorption of 20 to 80 per cent, that of 131 I, 60 Co and 54 Mn was not remarkable, and that of 85 Sr and 144 Ce was low absorption. The biological concentration of 137 Cs through pathways of food. In fishes taking up radionuclides through contaminated food, concentration factor increased in accordance with contamination level. In addition, radionuclides with small uptake but delayed excretion and those with high concentration rate could be the factors to decide the concentration factors of marine organisms. In order to study the relationship between metabolic activities and concentration, the uptake of one-year old fishes and adult fishes, and fishes fed and those non-fed were compared. One-year fishes took up large amount of 85 Sr during short period, however, concentration by metabolism in adult fishes was slow. Comparing feeding group and non-feeding group, the former showed 85 Sr concentration factor of 1.5 to 2 times that of the later, and the later showed 137 Cs concentration factor of 2 to 4 times that of the former. However, both uptake and excretion were rapid suggesting that taking food activated the metabolism of substances. (Kanao, N.)

Geomorphological applications of environmental radionuclides

International Nuclear Information System (INIS)

Quine, T.A.; Walling, D.

1998-01-01

Geomorphologists have shown increasing interest in environmental radionuclides since pioneering studies by Ritchie and McHenry in the USA and Campbell, Longmore and Loughran in Australia. Environmental radionuclides have attracted this interest because they provide geomorphologists with the means to trace sediment movement within the landscape. They, therefore, facilitate investigation of subjects at the core of geomorphology, namely the rates and patterns of landscape change. Most attention has been focussed on the artificial radionuclide caesium-137 ( 137 Cs) but more recently potential applications of the natural radionuclides lead-210 ( 210 Pb) and beryllium-7( 7 Be) have been investigated (Walling et al., 1995; Wallbrink and Murray, 1996a, 1996b). The origin, characteristics and applications of these radionuclides are summarised. These radionuclides are of value as sediment tracers because of three important characteristics: a strong affinity for sediment; a global distribution and the possibility of measurement at low concentration. Geomorphological applications of environmental radionuclides provide unique access to detailed qualitative data concerning landscape change over a range of timescales

Foodstuffs, radionuclides, monitoring

International Nuclear Information System (INIS)

Denisikov, A.I.

2000-01-01

Radionuclide contamination of water and food stuffs as a result of the Chernobyl accident and permissible contents of 90 Sr and 137 Cs are considered in brief. A method of radiation monitoring of food stuffs and water for the radionuclides mentioned is suggested. The method permits employment of the simplest and cheapest radiometric equipment for analysis, whole the high degree of radionuclide concentration using fiber sorbents permits using the instrumentation without expensive shields against external radiation. A description of ion-exchange unit for radiation monitoring of liquid samples of food stuffs or water, is provided [ru

Generator for radionuclide

International Nuclear Information System (INIS)

Weisner, P.S.; Forrest, T.R.F.

1985-01-01

This invention provides a radionuclide generator of the kind in which a parent radionuclide, adsorbed on a column of particulate material, generates a daughter radionuclide which is periodically removed from the column. This invention is particularly concerned with technetium generators using single collection vials. The generator comprises a column, a first reservoir for the eluent, a second reservoir to contain the volume of eluent required for a single elution, and means connecting the first reservoir to the second reservoir and the second reservoir to the column. Such a generator is particularly suitable for operation by vacuum elution

Process for encapsulating radionuclides

International Nuclear Information System (INIS)

Brownell, L.E.; Isaacson, R.E.

1976-01-01

Radionuclides are immobilized in virtually an insoluble form by reacting at a temperature of at least 90 0 C as an aqueous alkaline mixture having a solution pH of at least 10, containing a source of silicon, the radionuclide waste, and a metal cation. The molar ratio of silicon to the metal cation is on the order of unity to produce a gel from which complex metalosilicates crystallize to entrap the radionuclides within the resultant condensed crystal lattice. The product is a silicious stone-like material which is virtually insoluble and nonleachable in alkaline or neutral environment. One embodiment provides for the formation of the complex metalo-silicates, such as synthetic pollucite, by gel formation with subsequent calcination to the solid product; another embodiment utilizes a hydrothermal process, either above ground or deep within basalt caverns, at greater than atmospheric pressures and a temperature between 90 and 500 0 C to form complex metalo-silicates, such as strontium aluminosilicate. Another embodiment provides for the formation of complex metalo-silicates, such as synthetic pollucite, by slurrying an alkaline mixture of bentonite or kaolinite with a source of silicon and the radionuclide waste in salt form. In each of the embodiments a mobile system is achieved whereby the metalo-silicate constituents reorient into a condensed crystal lattice forming a cage structure with the condensed metalo-silicate lattice which completely surrounds the radionuclide and traps the radionuclide therein; thus rendering the radionuclide virtually insoluble

Reagents for Astatination of Biomolecules. 5. Evaluation of hydrazone linkers in 211At- and 125I-labeled closo-decaborate(2-) conjugates of Fab′ as a means of decreasing kidney retention

Science.gov (United States)

Wilbur, D. Scott; Chyan, Ming-Kuan; Hamlin, Donald K.; Nguyen, Holly; Vessella, Robert L.

2011-01-01

Evaluation of monoclonal antibody (MAb) fragments (e.g. Fab′, Fab or engineered fragments) as cancer-targeting reagents for therapy with the α-particle emitting radionuclide astatine-211 (211At) has been hampered by low in vivo stability of the label and a propensity of these proteins localize to kidneys. Fortunately, our group has shown that the low stability of the 211At label, generally a meta- or para-[211At]astatobenzoyl conjugate, on MAb Fab′ fragments can be dramatically improved by use of closo-decaborate(2-) conjugates. However, the higher stability of radiolabeled MAb Fab′ conjugates appears to result in retention of the radioactivity in kidneys. This investigation was conducted to evaluate whether the retention of radioactivity in kidney might be decreased by the use of acid-cleavable hydrazone between the Fab′ and the radiolabeled closo-decaborate(2-) moiety. Five conjugation reagents containing sulfhydryl-reactive maleimide groups, a hydrazone functionality and a closo-decaborate(2-) moiety were prepared. In four of the five conjugation reagents, a discrete polyethylene glycol (PEG) linker was used, and one substituent adjacent to the hydrazone was varied (phenyl, benzoate, anisole or methyl) to provide varying acid-sensitivity. In the initial studies, the five maleimido-closo-decaborate(2-) conjugation reagents were radioiodinated (125I or 131I), then conjugated with an anti-PSMA Fab′ (107-1A4 Fab′). Biodistributions of the five radioiodinated Fab′ conjugates were obtained in nude mice at 1, 4 and 24 h post injection (pi). In contrast to closo-decaborate(2-) conjugated to 107-1A4 Fab′ through a non-cleavable linker, two conjugates containing either a benzoate or a methyl substituent on the hydrazone functionality displayed clearance rates from kidney, liver and spleen that were similar to those obtained with directly radioiodinated Fab′ (i.e. no conjugate). The maleimido-closo-decaborate(2-) conjugation reagent containing a benzoate

Bacteriophytochromes control conjugation in Agrobacterium fabrum.

Science.gov (United States)

Bai, Yingnan; Rottwinkel, Gregor; Feng, Juan; Liu, Yiyao; Lamparter, Tilman

2016-08-01

Bacterial conjugation, the transfer of single stranded plasmid DNA from donor to recipient cell, is mediated through the type IV secretion system. We performed conjugation assays using a transmissible artificial plasmid as reporter. With this assay, conjugation in Agrobacterium fabrum was modulated by the phytochromes Agp1 and Agp2, photoreceptors that are most sensitive in the red region of visible light. In conjugation studies with wild-type donor cells carrying a pBIN-GUSINT plasmid as reporter that lacked the Ti (tumor inducing) plasmid, no conjugation was observed. When either agp1(-) or agp2(-) knockout donor strains were used, plasmid DNA was delivered to the recipient, indicating that both phytochromes suppress conjugation in the wild type donor. In the recipient strains, the loss of Agp1 or Agp2 led to diminished conjugation. When wild type cells with Ti plasmid and pBIN-GUS reporter plasmid were used as donor, a high rate of conjugation was observed. The DNA transfer was down regulated by red or far-red light by a factor of 3.5. With agp1(-) or agp2(-) knockout donor cells, conjugation in the dark was about 10 times lower than with the wild type donor, and with the double knockout donor no conjugation was observed. These results imply that the phytochrome system has evolved to inhibit conjugation in the light. The decrease of conjugation under different temperature correlated with the decrease of phytochrome autophosphorylation. Copyright © 2015 Elsevier B.V. All rights reserved.

Radionuclide transfer from mother to embryo

International Nuclear Information System (INIS)

Toader, M.; Vasilache, R.A.; Scridon, R.; Toader, M.L.

1998-01-01

The transfer of radionuclides from mother to embryo is still a matter of high interest. Therefore, the relation was investigated between the amount of radionuclides in the embryo and the dietary intake of the mother, this for two scenarios: a recurrent intake of variable amounts of radionuclides, and a long-term intake of a relatively constant amount of radionuclides, the radionuclide being 137 Cs. In the first case, the amount of radionuclides present in the embryo increases with the age of the embryo and with the intake of the mother. In the second case, no correlation could be found between the age of the embryo and its radioactive content; only the correlation between the intake of the mother and the radionuclide content of the embryo remained. (A.K.)

Polymers for Protein Conjugation

Directory of Open Access Journals (Sweden)

Gianfranco Pasut

2014-01-01

Full Text Available Polyethylene glycol (PEG at the moment is considered the leading polymer for protein conjugation in view of its unique properties, as well as to its low toxicity in humans, qualities which have been confirmed by its extensive use in clinical practice. Other polymers that are safe, biodegradable and custom-designed have, nevertheless, also been investigated as potential candidates for protein conjugation. This review will focus on natural polymers and synthetic linear polymers that have been used for protein delivery and the results associated with their use. Genetic fusion approaches for the preparation of protein-polypeptide conjugates will be also reviewed and compared with the best known chemical conjugation ones.

Radionuclide imaging of spinal infections

International Nuclear Information System (INIS)

Gemmel, Filip; Dumarey, Nicolas; Palestro, Christopher J.

2006-01-01

The diagnosis of spinal infection, with or without implants, has been a challenge for physicians for many years. Spinal infections are now being recognised more frequently, owing to aging of the population and the increasing use of spinal-fusion surgery. The diagnosis in many cases is delayed, and this may result in permanent neurological damage or even death. Laboratory evidence of infection is variable. Conventional radiography and radionuclide bone imaging lack both sensitivity and specificity. Neither in vitro labelled leucocyte scintigraphy nor 99m Tc-anti-granulocyte antibody scintigraphy is especially useful, because of the frequency with which spinal infection presents as a non-specific photopenic area on these tests. Sequential bone/gallium imaging and 67 Ga-SPECT are currently the radionuclide procedures of choice for spinal osteomyelitis, but these tests lack specificity, suffer from poor spatial resolution and require several days to complete. [ 18 F]Fluoro-2-deoxy-D-glucose (FDG) PET is a promising technique for diagnosing spinal infection, and has several potential advantages over conventional radionuclide tests. The study is sensitive and is completed in a single session, and image quality is superior to that obtained with single-photon emitting tracers. The specificity of FDG-PET may also be superior to that of conventional tracers because degenerative bone disease and fractures usually do not produce intense FDG uptake; moreover, spinal implants do not affect FDG imaging. However, FDG-PET images have to be read with caution in patients with instrumented spinal-fusion surgery since non-specific accumulation of FDG around the fusion material is not uncommon. In the future, PET-CT will likely provide more precise localisation of abnormalities. FDG-PET may prove to be useful for monitoring response to treatment in patients with spinal osteomyelitis. Other tracers for diagnosing spinal osteomyelitis are also under investigation, including radiolabelled

Radionuclide diagnosis of emergency states

International Nuclear Information System (INIS)

Ishmukhametov, A.I.

1985-01-01

Solution of emergency state radionuclide diagnostics from the technical point of view is provided by the application of the mobile quick-operating equipment in combination with computers, by the use of radionuclides with acceptable for emergency medicine characteristics and by development of radionuclide investigation data propcessing express-method. Medical developments include the study of acute disease and injury radioisotope semiotics, different indication diagnostic value determining, comparison of the results, obtained during radionuclide investigation, with clinicolaboratory and instrumental data, separation of methodical complex series

Anthropogenic radionuclides in the environment

Energy Technology Data Exchange (ETDEWEB)

Hu, Q; Weng, J; Wang, J

2007-11-15

Studies of radionuclides in the environment have entered a new era with the renaissance of nuclear energy and associated fuel reprocessing, geological disposal of high-level nuclear wastes, and concerns about national security with respect to nuclear non-proliferation. This work presents an overview of anthropogenic radionuclide contamination in the environment, as well as the salient geochemical behavior of important radionuclides. We first discuss the following major anthropogenic sources and current development that contribute to the radionuclide contamination of the environment: (1) nuclear weapons program; (2) nuclear weapons testing; (3) nuclear power plants; (4) commercial fuel reprocessing; (5) geological repository of high-level nuclear wastes, and (6) nuclear accidents. Then, we summarize the geochemical behavior for radionuclides {sup 99}Tc, {sup 129}I, and {sup 237}Np, because of their complex geochemical behavior, long half-lives, and presumably high mobility in the environment. Biogeochemical cycling and environment risk assessment must take into account speciation of these redox-sensitive radionuclides.

Radionuclide daughter inventory generator code: DIG

International Nuclear Information System (INIS)

Fields, D.E.; Sharp, R.D.

1985-09-01

The Daughter Inventory Generator (DIG) code accepts a tabulation of radionuclide initially present in a waste stream, specified as amounts present either by mass or by activity, and produces a tabulation of radionuclides present after a user-specified elapsed time. This resultant radionuclide inventory characterizes wastes that have undergone daughter ingrowth during subsequent processes, such as leaching and transport, and includes daughter radionuclides that should be considered in these subsequent processes or for inclusion in a pollutant source term. Output of the DIG code also summarizes radionuclide decay constants. The DIG code was developed specifically to assist the user of the PRESTO-II methodology and code in preparing data sets and accounting for possible daughter ingrowth in wastes buried in shallow-land disposal areas. The DIG code is also useful in preparing data sets for the PRESTO-EPA code. Daughter ingrowth in buried radionuclides and in radionuclides that have been leached from the wastes and are undergoing hydrologic transport are considered, and the quantities of daughter radionuclide are calculated. Radionuclide decay constants generated by DIG and included in the DIG output are required in the PRESTO-II code input data set. The DIG accesses some subroutines written for use with the CRRIS system and accesses files containing radionuclide data compiled by D.C. Kocher. 11 refs

α-Methylprednisolone conjugated cyclodextrin polymer-based nanoparticles for rheumatoid arthritis therapy

Directory of Open Access Journals (Sweden)

Jungyeon Hwang

2008-10-01

Full Text Available Jungyeon Hwang1, Kathleen Rodgers2, James C Oliver3, Thomas Schluep11Insert Therapeutics, Inc., Pasadena, CA, USA; 2Livingston Research Institute, Los Angeles, CA, USA; James C Oliver, Peptagen, Inc., Raleigh, NC USAAbstract: A glycinate derivative of α-methylprednisolone (MP was prepared and conjugated to a linear cyclodextrin polymer (CDP with a loading of 12.4% w/w. The polymer conjugate (CDP-MP self-assembled into nanoparticles with a size of 27 nm. Release kinetics of MP from the polymer conjugate showed a half-life (t1/2 of 50 h in phosphate buffer solution (PBS and 19 h in human plasma. In vitro, the proliferation of human lymphocytes was suppressed to a similar extent but with a delayed effect when CDP-MP was compared with free MP. In vivo, CDP-MP was administered intravenously to mice with collagen-induced arthritis and compared with free MP. CDP-MP was administered weekly for six weeks (0.07, 0.7, and 7 mg/kg/week and MP was administered daily for six weeks (0.01, 0.1, and 1 mg/kg/day. Body weight changes were minimal in all animals. After 28 days, a significant decrease in arthritis score was observed in animals treated weekly with an intermediate or high dose of CDP-MP. Additionally, dorsoplantar swelling was reduced to baseline in animals treated with CDP-MP at the intermediate and high dose level. Histological evaluation showed a reduction in synovitis, pannus formation and disruption of architecture at the highest dose level of CDP-MP. MP administered daily at equivalent cumulative doses showed minimal efficacy in this model. This study demonstrates that conjugation of MP to a cyclodextrin-polymer may improve its efficacy, leading to lower doses and less frequent administration for a safer and more convenient management of rheumatoid arthritis.Keywords: α-methylprednisolone (MP, cyclodextrin polymer (CDP, polymer conjugate (CDP-MP, rheumatoid arthritis (RA, enhanced permeability and retention effect (EPR

Radionuclide scintimetry for diagnosis of complications following femoral neck fracture

International Nuclear Information System (INIS)

Alberts, K.A.; Dahlborn, M.; Hindmarsh, J.; Soederborg, B.; Ringertz, H.

1984-01-01

A scintimetric study using Tc-99m MDP was made of 54 patients with delayed union, nonunion, or late segmental collapse of the femoral head, 4-92 months after femoral neck fracture. In radiographically verified collapse, the radionuclide uptake ratio between the femoral head on the fractured and on the intact side (HHR) was significantly higher than in fractures resulting in delayed union or nonunion. On the basis of scintimetric and radiographic findings, the patients with healing disturbances could be divided into three groups, characterized by the following features: (1) Satisfactory post-reduction position of the fracture without subsequent redisplacement and a high HHR, which as a rule turned out to be delayed union; (2) The same radiographic pattern but with a lower HHR, which in most cases resulted in nonunion; (3) Inadequate reduction or early redisplacement of the fracture with a high HHR, which resulted in nonunion. The fractional precision in discriminating between different types of disturbed fracture healing by means of skeletal scintimetry was 0.86 in this study. This non-invasive and technically simple method would therefore be a valuable complement to radiography in the assessment of healing, more than 4 months after fracture of the femoral neck. (author)

Critical review: Radionuclide transport, sediment transport, and water quality mathematical modeling; and radionuclide adsorption/desorption mechanisms

Energy Technology Data Exchange (ETDEWEB)

Onishi, Y.; Serne, R.J.; Arnold, E.M.; Cowan, C.E.; Thompson, F.L. [Pacific Northwest Lab., Richland, WA (United States)

1981-01-01

This report describes the results of a detailed literature review of radionuclide transport models applicable to rivers, estuaries, coastal waters, the Great Lakes, and impoundments. Some representatives sediment transport and water quality models were also reviewed to evaluate if they can be readily adapted to radionuclide transport modeling. The review showed that most available transport models were developed for dissolved radionuclide in rivers. These models include the mechanisms of advection, dispersion, and radionuclide decay. Since the models do not include sediment and radionuclide interactions, they are best suited for simulating short-term radionuclide migration where: (1) radionuclides have small distribution coefficients; (2) sediment concentrations in receiving water bodies are very low. Only 5 of the reviewed models include full sediment and radionuclide interactions: CHMSED developed by Fields; FETRA SERATRA, and TODAM developed by Onishi et al, and a model developed by Shull and Gloyna. The 5 models are applicable to cases where: (1) the distribution coefficient is large; (2) sediment concentrations are high; or (3) long-term migration and accumulation are under consideration. The report also discusses radionuclide absorption/desorption distribution ratios and addresses adsorption/desorption mechanisms and their controlling processes for 25 elements under surface water conditions. These elements are: Am, Sb, C, Ce, Cm, Co, Cr, Cs, Eu, I, Fe, Mn, Np, P, Pu, Pm, Ra, Ru, Sr, Tc, Th, {sup 3}H, U, Zn and Zr.

Preparation and evaluation of a radiogallium complex-conjugated bisphosphonate as a bone scintigraphy agent

International Nuclear Information System (INIS)

Ogawa, Kazuma; Takai, Kenichiro; Kanbara, Hiroya; Kiwada, Tatsuto; Kitamura, Yoji; Shiba, Kazuhiro; Odani, Akira

2011-01-01

Introduction: 68 Ga is a radionuclide of great interest as a positron emitter for positron emission tomography (PET). To develop a new bone-imaging agent with radiogallium, 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid (DOTA) was chosen as a chelating site and Ga-DOTA complex-conjugated bisphosphonate, which has a high affinity for bone, was prepared and evaluated. Although we are interested in developing 68 Ga-labeled bone imaging agents for PET, in these initial studies 67 Ga was used because of its longer half-life. Methods: DOTA-conjugated bisphosphonate (DOTA-Bn-SCN-HBP) was synthesized by conjugation of 2-(4-isothiocyanatebenzyl)-1,4,7,10-tetraazacyclododecane-1,4,7, 10-tetraacetic acid to 4-amino-1-hydroxybutylidene-1,1-bisphosphonate (alendronate). 67 Ga-DOTA-Bn-SCN-HBP was prepared by coordination with 67 Ga, and its in vitro and in vivo evaluations were performed. Results: 67 Ga-DOTA-Bn-SCN-HBP was prepared with a radiochemical purity of over 95% without purification. 67 Ga-DOTA-Bn-SCN-HBP had great affinity for hydroxyapatite in binding assay. In biodistribution experiments, 67 Ga-DOTA-Bn-SCN-HBP accumulated in bone rapidly but was hardly observed in tissues other than bone. Pretreatment of an excess amount of alendronate inhibited the bone accumulation of 67 Ga-DOTA-Bn-SCN-HBP. Conclusions: 67 Ga-DOTA-Bn-SCN-HBP showed ideal biodistribution characteristics as a bone-imaging agent. These findings should provide useful information on the drug design of bone imaging agents for PET with 68 Ga.

History of medical radionuclide production.

Science.gov (United States)

Ice, R D

1995-11-01

Radionuclide production for medical use originally was incidental to isotope discoveries by physicists and chemists. Once the available radionuclides were identified they were evaluated for potential medical use. Hevesy first used 32P in 1935 to study phosphorous metabolism in rats. Since that time, the development of cyclotrons, linear accelerators, and nuclear reactors have produced hundreds of radionuclides for potential medical use. The history of medical radionuclide production represents an evolutionary, interdisciplinary development of applied nuclear technology. Today the technology is represented by a mature industry and provides medical benefits to millions of patients annually.

Prognostic value of quantitative furosemide radionuclide renography in obstructive nephropathy

International Nuclear Information System (INIS)

Schuemichen, C.; Fischer, R.; Sierke, P.; Joseph, A.; Krause, T.

1988-01-01

Diuretic radionuclide renography is applied in patients with hydronephrosis in order to distinguish dilated, non-obstructed systems from those with significant mechanical obstruction. This is done after furosemide application by (semi) quantification of pelvic radioactivity outflow. In the dilated, non-obstructed pelvis, this outflow is increased, whereas in mechanical obstructed systems no response or even a decreased outflow is observed. It was expected that the latter outcome of the test is associated with an impaired renal function due to obstructive nephropathy. In the case that furosemide was given 30 min after 123 I hippuran application, this assumption could not be proved. When furosemide and 123 I hippuran were applied simultaneously, only a poor correlation was found between the response of pelvic outflow and the individual tubular clearance of the affected kidney. On the other hand, there was a clear correlation between the delay of pelvic outflow in the non-diuretic radionuclide renography and the individual tubular clearance. It can therefore be concluded that this test has little prognostic value and that other criteria in addition to the quantification of diuretic pelvic outflow are necessary for providing more reliable results. (orig.)

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

Science.gov (United States)

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

2013-04-01

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

Optical phase conjugation

CERN Document Server

Fisher, Robert A

1983-01-01

This book appears at a time of intense activity in optical phase conjugation. We chose not to await the maturation of the field, but instead to provide this material in time to be useful in its development. We have tried very hard to elucidate and interrelate the various nonlinear phenomena which can be used for optical phase conjugation.

Country report: Cuba. Local Production of 90Y And 188Re Radionuclides and Development of Radiopharmaceuticals for Therapy

International Nuclear Information System (INIS)

Xiques, Abmel; Hernández, Ignacio; Leyva, René; Pérez, Marylaine; Alonso, Luis Michel; Zamora, Minelys

2010-01-01

During the first period of this CRP we could test an efficient and reliable generator system based on ion-chromatography to obtain 90 Y from its parent radionuclide 90 Sr. This production scheme for 90 Y was outlined in the previous CRP related with the development of generator technologies. Quality parameters such as trace metals that can potentially interfere in the labeling of biomoléculas, 90 Y recovery, 90 Sr/ 90 Y ratio and radiation dose to bed matrix were evaluated. The results showed that high recovery and radionuclidic purity could be obtained for 90 Y during its repeated separation from the 90 Sr cow. No replacement or treatment of the cow were necessary and low waste generation and 90 Sr losses less that 0.1% after each run were also observed during the present study. A Fab’ fragment was enzimatically produced and purified from the monoclonal antibody h-R3 (Nimotuzumab®). The fragment and the parent antibody were successfully conjugated with DOTA and labeled with 90 Y. The radioinmunoconjugate thus obtained also exhibited a good 24 h in-vitro stability in an excess of DTPA. A 90 Y radiocoloid was prepared in a cromic phosphate particle for radiosynoviorthesis with promising results in animal models. Two alumina based 188 W/ 188 Re generators were prepared and their eluates were used in the labeling of hR3-DOTA conjugates. Quality control and in vivo evaluation in comparison with 99m Tc-hR3 showed very good results and similar pattern of distribution and pharmacokinetic and will be used in clinical trials for cancer patients. (author)

Conditions and processes affecting radionuclide transport

Science.gov (United States)

Simmons, Ardyth M.; Neymark, Leonid A.

2012-01-01

Characteristics of host rocks, secondary minerals, and fluids would affect the transport of radionuclides from a previously proposed repository at Yucca Mountain, Nevada. Minerals in the Yucca Mountain tuffs that are important for retarding radionuclides include clinoptilolite and mordenite (zeolites), clay minerals, and iron and manganese oxides and hydroxides. Water compositions along flow paths beneath Yucca Mountain are controlled by dissolution reactions, silica and calcite precipitation, and ion-exchange reactions. Radionuclide concentrations along flow paths from a repository could be limited by (1) low waste-form dissolution rates, (2) low radionuclide solubility, and (3) radionuclide sorption onto geological media.

Unexpected radionuclide uptake due to calcification in muscles

International Nuclear Information System (INIS)

Khier, A.

1999-01-01

Full text: A male patient aged 27 years was injected with 1000 MBq of 99 Tc m -MDP. The patient was an active man indulging in contact sport. He presented with lower back and pelvic pain. Spot pictures were made of the pelvis, lumbar spine and femurs. Unexpected active radionuclide uptake in the muscles was seen. In the delayed static images, there was focal accumulation of tracer uptake in the muscles overlying the mid-shaft of the left femur consistent with myositis ossificans. Myositis ossificans is a benign ossifying process that is generally solitary and well circumscribed. It is most commonly found in the muscles but it may occur in other connective tissues, especially tendons and subcutaneous fat. This was presumably associated with chronic muscular injuries contracted during sports activity

Qualidade conjugal: mapeando conceitos

Directory of Open Access Journals (Sweden)

Clarisse Mosmann

2006-12-01

Full Text Available Apesar da ampla utilização do conceito de qualidade conjugal, identifica-se falta de clareza conceitual acerca das variáveis que o compõem. Esse artigo apresenta revisão da literatura na área com o objetivo de mapear o conceito de qualidade conjugal. Foram analisadas sete principais teorias sobre o tema: Troca Social, Comportamental, Apego, Teoria da Crise, Interacionismo Simbólico. Pelos postulados propostos nas diferentes teorias, podem-se identificar três grupos de variáveis fundamentais na definição da qualidade conjugal: recursos pessoais dos cônjuges, contexto de inserção do casal e processos adaptativos. Neste sentido, a qualidade conjugal é resultado do processo dinâmico e interativo do casal, razão deste caráter multidimensional.

A Method to Determine Oscillation Emergence Bifurcation in Time-Delayed LTI System with Single Lag

Directory of Open Access Journals (Sweden)

Yu Xiaodan

2014-01-01

Full Text Available One type of bifurcation named oscillation emergence bifurcation (OEB found in time-delayed linear time invariant (abbr. LTI systems is fully studied. The definition of OEB is initially put forward according to the eigenvalue variation. It is revealed that a real eigenvalue splits into a pair of conjugated complex eigenvalues when an OEB occurs, which means the number of the system eigenvalues will increase by one and a new oscillation mode will emerge. Next, a method to determine OEB bifurcation in the time-delayed LTI system with single lag is developed based on Lambert W function. A one-dimensional (1-dim time-delayed system is firstly employed to explain the mechanism of OEB bifurcation. Then, methods to determine the OEB bifurcation in 1-dim, 2-dim, and high-dimension time-delayed LTI systems are derived. Finally, simulation results validate the correctness and effectiveness of the presented method. Since OEB bifurcation occurs with a new oscillation mode emerging, work of this paper is useful to explore the complex phenomena and the stability of time-delayed dynamic systems.

Radionuclides in air, water, and biota

International Nuclear Information System (INIS)

Seymour, A.H.; Nelson, V.A.

1977-01-01

Air, water, and biological samples collected before and after the 1965, 1969, and 1971 underground nuclear detonations at Amchitka Island were analyzed for natural and fallout radionuclides by gamma spectrometry. Selected samples were also analyzed for tritium, 55 Fe, and 90 Sr. The objectives were to search for and identify radionuclides of Amchitka origin in the samples and to contribute to the general knowledge of the distribution of radionuclides in the environment. The studies showed that there has been no escape of radionuclides from the underground sites of the three nuclear detonations at Amchitka Island except for trace quantities of radionuclides, principally tritium, in water and soil gas samples from the immediate vicinity of the surface ground zero for the 1965 event. Two naturally occurring radionuclides, 40 K and 7 Be, were the most abundant radionuclides in the samples, usually by a factor of 10 or more, except for 137 Cs in lichen samples. All levels were well below applicable Radiation Protction Guides, often being near the statistical limit of detection

Phytoremediation of radionuclides: an emerging alternative

International Nuclear Information System (INIS)

Singh, Shraddha

2013-01-01

Proliferation of nuclear power industry, nuclear weapon testing, dismantling of existing nuclear weapons and occasional accidents have contributed to an enhancement in the level of radionuclides in the environment. The radionuclides due to their long half life and transfer through the food chain effect adversely to normal biological systems. Hence, it is essential to effectively remove the radionuclides from contaminated soils and solutions. Phytoremediation - the use of plants for remediation of toxic metals and radionuclides has been recognized as an aesthetically pleasing, low cost and environment friendly in situ method. Phytoremediation is an umbrella term which covers several plant based approaches. Plants have shown the potential of remediation of these radionuclides from spiked solutions, low level nuclear waste and soil. Various aspects of phytoremediation as well as potential of various plants for remediation of radionuclides will be discussed here. (author)

Radionuclide migration test using undisturbed aerated soil

International Nuclear Information System (INIS)

Yamamoto, Tadatoshi; Ohtsuka, Yoshiro; Ogawa, Hiromichi; Wadachi, Yoshiki

1988-01-01

As one of the most important part of safety assessment on the shallow land disposal of lowlevel radioactive waste, the radionuclide migration was studied using undisturbed soil samples, in order to evaluate an exact radionuclide migration in an aerated soil layer. Soil samples used in the migration test were coastal sand and loamy soil which form typical surface soil layers in Japan. The aqueous solution containing 60 CoCl 2 , 85 SrCl 2 and 137 CsCl was fed into the soil column and concentration of each radionuclide both in effluent and in soil was measured. Large amount of radionuclides was adsorbed on the surface of soil column and small amount of radionuclides moved deep into the soil column. Difference in the radionuclide profile was observed in the low concentration portion particularly. It is that some fractions of 60 Co and 137 Cs are stable in non-ionic form and move downward through the soil column together with water. The radionuclide distribution in the surface of soil column can be fairly predicted with a conventional migration equation for ionic radionuclides. As a result of radionuclide adsorption, both aerated soil layers of coastal sand and loamy soil have large barrier ability on the radionuclide migration through the ground. (author)

Radionuclides in food

International Nuclear Information System (INIS)

Fernandez Gomez, Isis Maria

2008-01-01

The sources of the presence of radionuclides in food are presented: natural radiation and artificial radiation. The transfer of radionuclides through food chains, intakes of radionuclides to the body with its partners effective doses and typical consumption of basic foods of a rural adult population are exposed as main topics. Also the radiation doses from natural sources and exposure to man by ingestion of contaminated food with radionuclides of artificial origin are shown. The contribution of the food ingestion to the man exposure depends on: characteristics of radionuclide, natural conditions, farming practices and eating habits of the population. The principal international organizations in charge of setting guide levels for radionuclides in food are mentioned: standards, rules and the monitoring. It establishes that a guide is necessary for the food monitoring; the alone CODEX ALIMENTARIUS is applicable to emergency situations and the generic action levels proposed by the CODEX not satisfy all needs (no guiding international levels for planned or existing situations such as NORM). There are handled mainly socio-economic and political aspects. Among the actions to be taken are: to assure a public comprehensive information over the risk evaluation in food; to reinforce the collaboration among the different international organizations (WHO, IAEA, ICRP, EC) in relation with the food of set; to give follow-up to the control of the drinkable water and NORM's presence in the food. In addition, it is possible to create the necessary mechanisms to reduce the number of irrelevant measures and bureaucratic useless steps (certificates); to promote the exchange between the different institutions involved in the topic of the food, with relation to the acquired experiences and learned lessons. Likewise, it might examine the possibility of a multidisciplinary approximation (radioactive and not radioactive pollutants); to elaborate a technical guide to assure the

Initial Radionuclide Inventories

Energy Technology Data Exchange (ETDEWEB)

H. Miller

2004-09-19

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

Should single-phase radionuclide bone imaging be used in suspected osteomyelitis

International Nuclear Information System (INIS)

Fihn, S.D.; Larson, E.B.; Nelp, W.B.; Rudd, T.G.; Gerber, F.H.

1984-01-01

The records of 69 patients who had 86 delayed, static radionuclide bone images for suspected osteomyelitis were studied to determine the effects of this procedure on diagnosis and treatment. Sensitivity, specificity, and positive predictive value were lower than reported in several other studies. When osteomyelitis was unlikely, imaging was either negative or falsely positive and rarely affected treatment. In 46 cases where osteomyelitis was more likely, imaging potentially changed therapy in 19 but was unhelpful or misleading in 15. Static-phase images with ''definite'' interpretations, particularly when negative, are specific, but ''equivocal'' studies may lead to diagnostic and therapeutic errors. When ostemyelitis is improbable, imaging rarely changes diagnosis or therapy

Cross-Conjugated n-Dopable Aromatic Polyketone

NARCIS (Netherlands)

Voortman, Thomas P.; Bartesaghi, Davide; Koster, L. Jan Anton; Chiechi, Ryan C.

2015-01-01

This paper describes the synthesis and characterization of a high molecular weight cross-conjugated polyketone synthesized via scalable Friedel Crafts chemistry. Cross-conjugated polyketones are precursors to conjugated polyions; they become orders of magnitude more conductive after a two-electron

Determination of alpha radionuclides in fish

International Nuclear Information System (INIS)

Pernicka, L.; Matel, L.; Rosskopfova, O.

2001-01-01

In atmospheric water, external water and undercurrent the occurrence of radionuclides is usual. It is an important factor of quality of the environment. Plants ingest radionuclides from water and with they everyone. And it arises radioactivity infest food-chain. Radiotoxicity of this radionuclides is very deer sometimes. The sensitive radiochemical procedures for their determination are necessarily important. The poster presents the combined procedure used at our laboratory for determination of alpha radionuclides in biological samples. (authors)

Preparation, radioiodination and in vitro evaluation of a nido-carborane-dextran conjugate, a potential residualizing label for tumor targeting proteins and peptides

International Nuclear Information System (INIS)

Tolmachev, V.; Bruskin, A.; Uppsala University; Sjoeberg, S.; Carlsson, J.; Lundqvist, H.

2004-01-01

Polysaccharides are not degradable by proteolytic enzymes in lysosomes and do not diffuse through cellular membranes. Thus, attached to an internalizing, targeting protein, such polysaccharide linkers, will remain intracellularly after protein degradation. They can be labeled with halogens and provide then a so called residualizing label. Such an approach improves tumor-to-non-tumor radioactivity ratio and, consequently, the results of radionuclide diagnostics and therapy. A new approach to obtain a stable halogenation of the polysaccharide dextran using 7-(3-amino-propyl)-7,8-dicarba-nido-undecaborate (-) (ANC) is presented. Dextran T10 was partially oxidized by metaperiodate, and ANC was coupled to dextran by reductive amination. The conjugate was then labeled with 125 I using either Chloramine-T or IodoGen as oxidants. Labeling efficiency was 69-85%. Stability of the label was evaluated in rat liver homogenates. Under these conditions, the ANC-dextran conjugate was found to be more stable than labeled albumin, which was used as a control protein. (author)

Radionuclide usage survey 1979-80

International Nuclear Information System (INIS)

Woods, M.J.

1980-08-01

Details of a survey by the Life Sciences Working Group of the International Committee for Radionuclide Metrology (ICRM) on radionuclide usage by medical physicists in 11 countries are presented. The results indicate that the radionuclide which will be of most significance in the future will be F-18, Fe-52, Ga-67, Ga-68, Kr-81m, Tc-99m, In-111, I-123, Xe-127 and Tl-201, (U.K.)

Preparation and evaluation of a radiogallium complex-conjugated bisphosphonate as a bone scintigraphy agent

Energy Technology Data Exchange (ETDEWEB)

Ogawa, Kazuma, E-mail: kogawa@p.kanazawa-u.ac.jp [Graduate School of Natural Science and Technology, Kanazawa University, Kanazawa 920-1192 (Japan); Takai, Kenichiro; Kanbara, Hiroya; Kiwada, Tatsuto [Graduate School of Natural Science and Technology, Kanazawa University, Kanazawa 920-1192 (Japan); Kitamura, Yoji; Shiba, Kazuhiro [Advanced Science Research Center, Kanazawa University, Kanazawa 920-8640 (Japan); Odani, Akira [Graduate School of Natural Science and Technology, Kanazawa University, Kanazawa 920-1192 (Japan)

2011-07-15

Introduction: {sup 68}Ga is a radionuclide of great interest as a positron emitter for positron emission tomography (PET). To develop a new bone-imaging agent with radiogallium, 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid (DOTA) was chosen as a chelating site and Ga-DOTA complex-conjugated bisphosphonate, which has a high affinity for bone, was prepared and evaluated. Although we are interested in developing {sup 68}Ga-labeled bone imaging agents for PET, in these initial studies {sup 67}Ga was used because of its longer half-life. Methods: DOTA-conjugated bisphosphonate (DOTA-Bn-SCN-HBP) was synthesized by conjugation of 2-(4-isothiocyanatebenzyl)-1,4,7,10-tetraazacyclododecane-1,4,7, 10-tetraacetic acid to 4-amino-1-hydroxybutylidene-1,1-bisphosphonate (alendronate). {sup 67}Ga-DOTA-Bn-SCN-HBP was prepared by coordination with {sup 67}Ga, and its in vitro and in vivo evaluations were performed. Results: {sup 67}Ga-DOTA-Bn-SCN-HBP was prepared with a radiochemical purity of over 95% without purification. {sup 67}Ga-DOTA-Bn-SCN-HBP had great affinity for hydroxyapatite in binding assay. In biodistribution experiments, {sup 67}Ga-DOTA-Bn-SCN-HBP accumulated in bone rapidly but was hardly observed in tissues other than bone. Pretreatment of an excess amount of alendronate inhibited the bone accumulation of {sup 67}Ga-DOTA-Bn-SCN-HBP. Conclusions: {sup 67}Ga-DOTA-Bn-SCN-HBP showed ideal biodistribution characteristics as a bone-imaging agent. These findings should provide useful information on the drug design of bone imaging agents for PET with {sup 68}Ga.

YUCCA6 over-expression demonstrates auxin function in delaying leaf senescence in Arabidopsis thaliana

KAUST Repository

Kim, Jeong Im

2011-04-21

The Arabidopsis thaliana YUCCA family of flavin monooxygenase proteins catalyses a rate-limiting step in de novo auxin biosynthesis. A YUCCA6 activation mutant, yuc6-1D, has been shown to contain an elevated free IAA level and to display typical high-auxin phenotypes. It is reported here that Arabidopsis plants over-expressing YUCCA6, such as the yuc6-1D activation mutant and 35S:YUC6 transgenic plants, displayed dramatic longevity. In addition, plants over-expressing YUCCA6 exhibited classical, delayed dark-induced and hormone-induced senescence in assays using detached rosette leaves. However, plants over-expressing an allele of YUCCA6, that carries mutations in the NADPH cofactor binding site, exhibited neither delayed leaf senescence phenotypes nor phenotypes typical of auxin overproduction. When the level of free IAA was reduced in yuc6-1D by conjugation to lysine, yuc6-1D leaves senesced at a rate similar to the wild-type leaves. Dark-induced senescence in detached leaves was accompanied by a decrease in their free IAA content, by the reduced expression of auxin biosynthesis enzymes such as YUCCA1 and YUCCA6 that increase cellular free IAA levels, and by the increased expression of auxin-conjugating enzymes encoded by the GH3 genes that reduce the cellular free auxin levels. Reduced transcript abundances of SAG12, NAC1, and NAC6 during senescence in yuc6-1D compared with the wild type suggested that auxin delays senescence by directly or indirectly regulating the expression of senescence-associated genes. 2011 The Author(s).

Block-conjugate-gradient method

International Nuclear Information System (INIS)

McCarthy, J.F.

1989-01-01

It is shown that by using the block-conjugate-gradient method several, say s, columns of the inverse Kogut-Susskind fermion matrix can be found simultaneously, in less time than it would take to run the standard conjugate-gradient algorithm s times. The method improves in efficiency relative to the standard conjugate-gradient algorithm as the fermion mass is decreased and as the value of the coupling is pushed to its limit before the finite-size effects become important. Thus it is potentially useful for measuring propagators in large lattice-gauge-theory calculations of the particle spectrum

Radionuclides: Accumulation and Transport in Plants.

Science.gov (United States)

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

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

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

Science.gov (United States)

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

1999-03-23

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

Radionuclide transport processes in terrestrial ecosystems

International Nuclear Information System (INIS)

Whicker, F.W.

1983-01-01

Some major principles and the status of knowledge concerning the transport of radionuclides through terrestrial ecosystems are reviewed. Fundamental processes which control the flow of radionuclides between ecosystem components such as air, soil, plants, and animals are described, with emphasis on deposition, resuspension, plant uptake, ingestion, and assimilation. Properties of radionuclides, organisms, and ecosystems are examined in relation to their influence on the accumulation of radioactive materials by plants and animals. The effects of the physicochemical nature of the radionuclide; morphology, physiology, and behavior of the organism; and soil, nutrient, and trophic characteristics of the ecosystem are highlighted. Observations in natural ecosystems on radionuclides such as 137 Cs, 90 Sr, 131 I, 3 H, and 239 Pu are used to illustrate current concepts. An assessment of the degree to which the processes controlling radionuclide behavior are understood and of our ability to simulate and predict such behavior with computerized models is offered. Finally, brief comments are made on research needs

Radionuclide imaging of spinal infections

Energy Technology Data Exchange (ETDEWEB)

Gemmel, Filip [Ghent Maria-Middelares, General Hospital, Division of Nuclear Medicine, Ghent (Belgium); Medical Center Leeuwarden (MCL), Division of Nuclear Medicine, Henri Dunantweg 2, Postbus 888, Leeuwarden (Netherlands); Dumarey, Nicolas [Universite Libre de Bruxelles, Hopital Erasme, Division of Nuclear Medicine, Brussels (Belgium); Palestro, Christopher J. [Long Island Jewish Medical Center, Division of Nuclear Medicine, Long Island, NY (United States)

2006-10-15

The diagnosis of spinal infection, with or without implants, has been a challenge for physicians for many years. Spinal infections are now being recognised more frequently, owing to aging of the population and the increasing use of spinal-fusion surgery. The diagnosis in many cases is delayed, and this may result in permanent neurological damage or even death. Laboratory evidence of infection is variable. Conventional radiography and radionuclide bone imaging lack both sensitivity and specificity. Neither in vitro labelled leucocyte scintigraphy nor {sup 99m}Tc-anti-granulocyte antibody scintigraphy is especially useful, because of the frequency with which spinal infection presents as a non-specific photopenic area on these tests. Sequential bone/gallium imaging and {sup 67}Ga-SPECT are currently the radionuclide procedures of choice for spinal osteomyelitis, but these tests lack specificity, suffer from poor spatial resolution and require several days to complete. [{sup 18}F]Fluoro-2-deoxy-D-glucose (FDG) PET is a promising technique for diagnosing spinal infection, and has several potential advantages over conventional radionuclide tests. The study is sensitive and is completed in a single session, and image quality is superior to that obtained with single-photon emitting tracers. The specificity of FDG-PET may also be superior to that of conventional tracers because degenerative bone disease and fractures usually do not produce intense FDG uptake; moreover, spinal implants do not affect FDG imaging. However, FDG-PET images have to be read with caution in patients with instrumented spinal-fusion surgery since non-specific accumulation of FDG around the fusion material is not uncommon. In the future, PET-CT will likely provide more precise localisation of abnormalities. FDG-PET may prove to be useful for monitoring response to treatment in patients with spinal osteomyelitis. Other tracers for diagnosing spinal osteomyelitis are also under investigation, including

Protein carriers of conjugate vaccines

Science.gov (United States)

Pichichero, Michael E

2013-01-01

The immunogenicity of polysaccharides as human vaccines was enhanced by coupling to protein carriers. Conjugation transformed the T cell-independent polysaccharide vaccines of the past to T cell-dependent antigenic vaccines that were much more immunogenic and launched a renaissance in vaccinology. This review discusses the conjugate vaccines for prevention of infections caused by Hemophilus influenzae type b, Streptococcus pneumoniae, and Neisseria meningitidis. Specifically, the characteristics of the proteins used in the construction of the vaccines including CRM, tetanus toxoid, diphtheria toxoid, Neisseria meningitidis outer membrane complex, and Hemophilus influenzae protein D are discussed. The studies that established differences among and key features of conjugate vaccines including immunologic memory induction, reduction of nasopharyngeal colonization and herd immunity, and antibody avidity and avidity maturation are presented. Studies of dose, schedule, response to boosters, of single protein carriers with single and multiple polysaccharides, of multiple protein carriers with multiple polysaccharides and conjugate vaccines administered concurrently with other vaccines are discussed along with undesirable consequences of conjugate vaccines. The clear benefits of conjugate vaccines in improving the protective responses of the immature immune systems of young infants and the senescent immune systems of the elderly have been made clear and opened the way to development of additional vaccines using this technology for future vaccine products. PMID:23955057

Radionuclide Sensors for Water Monitoring

International Nuclear Information System (INIS)

Grate, Jay W.; Egorov, Oleg B.; DeVol, Timothy A.

2004-01-01

Radionuclide contamination in the soil and groundwater at U.S. Department of Energy (DOE) sites is a severe problem that requires monitoring and remediation. Radionuclide measurement techniques are needed to monitor surface waters, groundwater, and process waters. Typically, water samples are collected and transported to an analytical laboratory, where costly radiochemical analyses are performed. To date, there has been very little development of selective radionuclide sensors for alpha- and beta-emitting radionuclides such as 90Sr, 99Tc, and various actinides of interest. The objective of this project is to investigate novel sensor concepts and materials for sensitive and selective determination of beta- and alpha-emitting radionuclide contaminants in water. To meet the requirements for loW--level, isotope-specific detection, the proposed sensors are based on radiometric detection. As a means to address the fundamental challenge of the short ranges of beta and alpha particle s in water, our overall approach is based on localization of preconcentration/separation chemistries directly on or within the active area of a radioactivity detector. Automated microfluidics is used for sample manipulation and sensor regeneration or renewal. The outcome of these investigations will be the knowledge necessary to choose appropriate chemistries for selective preconcentration of radionuclides from environmental samples, new materials that combine chemical selectivity with scintillating properties, new materials that add chemical selectivity to solid-state diode detectors, new preconcentrating column sensors, and improved instrumentation and signal processing for selective radionuclide sensors. New knowledge will provide the basis for designing effective probes and instrumentation for field and in situ measurements

Radionuclides in terrestrial ecosystems

International Nuclear Information System (INIS)

Bocock, K.L.

1981-01-01

This report summarizes information on the distribution and movement of radionuclides in semi-natural terrestrial ecosystems in north-west England with particular emphasis on inputs to, and outputs from ecosystems; on plant and soil aspects; and on radionuclides in fallout and in discharges by the nuclear industry. (author)

Artificial radionuclides in soil, flora and fauna

International Nuclear Information System (INIS)

Marej, A.N.

1984-01-01

Sources and ways of soil contamination by radionuclides, as well as the main regularities of radionuclide behaviour in soils, are discussed. Ways of radionuclide uptake by plants are discussed in detail, since radionuclide contamination of vegetation, and agricultural plants and pastures in particular, is one of the main factors, determining sanitary value of environmental contamination by radioactive substances

Conjugated polymer zwitterions and solar cells comprising conjugated polymer zwitterions

Science.gov (United States)

Emrick, Todd; Russell, Thomas; Page, Zachariah; Liu, Yao

2018-06-05

A conjugated polymer zwitterion includes repeating units having structure (I), (II), or a combination thereof ##STR00001## wherein Ar is independently at each occurrence a divalent substituted or unsubstituted C3-30 arylene or heteroarylene group; L is independently at each occurrence a divalent C1-16 alkylene group, C6-30arylene or heteroarylene group, or alkylene oxide group; and R1 is independently at each occurrence a zwitterion. A polymer solar cell including the conjugated polymer zwitterion is also disclosed.

Environmental behaviour of radionuclides and transfer to man

International Nuclear Information System (INIS)

Smith, H.

1982-01-01

The environmental behaviour of the radionuclides making the major contribution to man's irradiation through diet is described. The following stages are emphasized: transfer of radionuclides to plants; transfer of radionuclides to animals; metabolism of inhaled or ingested radionuclides in animals providing food for man; transfer of radionuclides through the aquatic environment; application of food chain models. (43 references)

Research study of conjugate materials; Conjugate material no chosa kenkyu

Energy Technology Data Exchange (ETDEWEB)

NONE

1998-03-01

The paper reported an introductory research on possibilities of new glass `conjugate materials.` The report took up the structure and synthetic process of conjugate materials to be researched/developed, classified them according to structural elements on molecular, nanometer and cluster levels, and introduced the structures and functions. Further, as glasses with new functions to be proposed, the paper introduced transparent and high-strength glass used for houses and vehicles, light modulation glass which realizes energy saving and optical data processing, and environmentally functional glass which realizes environmental cleaning or high performance biosensor. An initial survey was also conducted on rights of intellectual property to be taken notice of in Japan and abroad in the present situation. Reports were summed up and introduced of Osaka National Research Institute, Electrotechnical Laboratory, and National Industrial Research Institute of Nagoya which are all carrying out leading studies of conjugate materials. 235 refs., 135 figs., 6 tabs.

Radioactivity: radionuclides in foods

International Nuclear Information System (INIS)

Simpson, R.E.; Baratta, E.J.; Jelinek, C.F.

1977-01-01

The results are summarized of the analysis for strontium-90, cesium-137, iodine-131, ruthenium-106, and potassium-40, a naturally occurring radionuclide, in samples of total diet and selected import commodities in the foods compliance program of the Food and Drug Administration. On the basis of the radionuclide intake guidelines established by the Federal Radiation Council (FRC), the low content of radionuclides found in the total diet samples for fiscal years 1973 and 1974 demonstrates the need for surveillance only at the present level. The low levels of radionuclides found in a limited number of edible imported commodities indicate that their contribution to the total diet would not increase the levels of these radionuclides above those recommended for only periodic surveillance by the FRC. The potassium levels, determined from potassium-40 activity, found in meats and fish agree with the value for normal muscle tissue for the reference man reported by the International Commission on Radiation Protection. Of the other commodities, nuts contained the highest levels, while sugar, beverages, and processed foods contained the lowest levels of potassium. Although cesium and potassium are chemical analogs with similar metabolic properties, because of their variable content in some leafy samples as a result of surface contamination, a correlation between cesium-137 levels and the cesium-137-to-potassium ratio was inconclusive

Inverse problem in radionuclide transport

International Nuclear Information System (INIS)

Yu, C.

1988-01-01

The disposal of radioactive waste must comply with the performance objectives set forth in 10 CFR 61 for low-level waste (LLW) and 10 CFR 60 for high-level waste (HLW). To determine probable compliance, the proposed disposal system can be modeled to predict its performance. One of the difficulties encountered in such a study is modeling the migration of radionuclides through a complex geologic medium for the long term. Although many radionuclide transport models exist in the literature, the accuracy of the model prediction is highly dependent on the model parameters used. The problem of using known parameters in a radionuclide transport model to predict radionuclide concentrations is a direct problem (DP); whereas the reverse of DP, i.e., the parameter identification problem of determining model parameters from known radionuclide concentrations, is called the inverse problem (IP). In this study, a procedure to solve IP is tested, using the regression technique. Several nonlinear regression programs are examined, and the best one is recommended. 13 refs., 1 tab

Radionuclide Retention in Concrete Wasteforms

Energy Technology Data Exchange (ETDEWEB)

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

2012-09-24

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

Gold nanorod-mediated hyperthermia enhances the efficacy of HPMA copolymer-90Y conjugates in treatment of prostate tumors

International Nuclear Information System (INIS)

Buckway, Brandon; Frazier, Nick; Gormley, Adam J.; Ray, Abhijit; Ghandehari, Hamidreza

2014-01-01

Introduction: The treatment of prostate cancer using a radiotherapeutic 90 Y labeled N-(2-hydroxypropyl)methacrylamide (HPMA) copolymer can be enhanced with localized tumor hyperthermia. An 111 In labeled HPMA copolymer system for single photon emission computerized tomography (SPECT) was developed to observe the biodistribution changes associated with hyperthermia. Efficacy studies were conducted in prostate tumor bearing mice using the 90 Y HPMA copolymer with hyperthermia. Methods: HPMA copolymers containing 1, 4, 7, 10-tetraazacyclododecane-1,4,7,10-tetraacetic acid (DOTA) were synthesized by reversible addition-fragmentation transfer (RAFT) copolymerization and subsequently labeled with either 111 In for imaging or 90 Y for efficacy studies. Radiolabel stability was characterized in vitro with mouse serum. Imaging and efficacy studies were conducted in DU145 prostate tumor bearing mice. Imaging was performed using single photon emission computerized tomography (SPECT). Localized mild tumor hyperthermia was achieved by plasmonic photothermal therapy using gold nanorods. Results: HPMA copolymer-DOTA conjugates demonstrated efficient labeling and stability for both radionuclides. Imaging analysis showed a marked increase of radiolabeled copolymer within the hyperthermia treated prostate tumors, with no significant accumulation in non-targeted tissues. The greatest reduction in tumor growth was observed in the hyperthermia treated tumors with 90 Y HPMA copolymer conjugates. Histological analysis confirmed treatment efficacy and safety. Conclusion: HPMA copolymer-DOTA conjugates radiolabeled with both the imaging and treatment radioisotopes, when combined with hyperthermia can serve as an image guided approach for efficacious treatment of prostate tumors

Sediment and radionuclide transport in rivers: radionuclide transport modeling for Cattaraugus and Buttermilk Creeks, New York

International Nuclear Information System (INIS)

Onishi, Y.; Yabusaki, S.B.; Kincaid, C.T.; Skaggs, R.L.; Walters, W.H.

1982-12-01

SERATRA, a transient, two-dimensional (laterally-averaged) computer model of sediment-contaminant transport in rivers, satisfactorily resolved the distribution of sediment and radionuclide concentrations in the Cattaraugus Creek stream system in New York. By modeling the physical processes of advection, diffusion, erosion, deposition, and bed armoring, SERATRA routed three sediment size fractions, including cohesive soils, to simulate three dynamic flow events. In conjunction with the sediment transport, SERATRA computed radionuclide levels in dissolved, suspended sediment, and bed sediment forms for four radionuclides ( 137 Cs, 90 Sr, 239 240 Pu, and 3 H). By accounting for time-dependent sediment-radionuclide interaction in the water column and bed, SERATA is a physically explicit model of radionuclide fate and migration. Sediment and radionuclide concentrations calculated by SERATA in the Cattaraugus Creek stream system are in reasonable agreement with measured values. SERATRA is in the field performance phase of an extensive testing program designed to establish the utility of the model as a site assessment tool. The model handles not only radionuclides but other contaminants such as pesticides, heavy metals and other toxic chemicals. Now that the model has been applied to four field sites, including the latest study of the Cattaraugus Creek stream system, it is recommended that a final model be validated through comparison of predicted results with field data from a carefully controlled tracer test at a field site. It is also recommended that a detailed laboratory flume be tested to study cohesive sediment transport, deposition, and erosion characteristics. The lack of current understanding of these characteristics is one of the weakest areas hindering the accurate assessment of the migration of radionuclides sorbed by fine sediments of silt and clay

Modeling Radionuclide Decay Chain Migration Using HYDROGEOCHEM

Science.gov (United States)

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

2014-12-01

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

Misonidazole-glutathione conjugates in CHO cells

International Nuclear Information System (INIS)

Varghese, A.J.; Whitmore, G.F.

1984-01-01

Misonidazole, after reduction to the hydroxylamine derivative, reacts with glutathione (GSH) under physiological conditions. The reaction product has been identified as a mixture of two isomeric conjugates. When water soluble extracts of CHO cells exposed to misonidazole under hypoxic conditions are subjected to HPLC analysis, misonidazole derivatives, having the same chromatographic properties as the GSH-MISO conjugates, were detected. When CHO cells were incubated with misonidazole in the presence of added GSH, a substantial increase in the amount of the conjugate was detected. When extracts of CHO cells exposed to misonidazole under hypoxia were subsequently exposed to GSH, an increased formation of the conjugate was observed. A rearrangement product of the hydroxylamine derivative of misonidazole is postulated as the reactive intermediate responsible for the formation of the conjugate

Modelling conjugation with stochastic differential equations

DEFF Research Database (Denmark)

Philipsen, Kirsten Riber; Christiansen, Lasse Engbo; Hasman, Henrik

2010-01-01

Enterococcus faecium strains in a rich exhaustible media. The model contains a new expression for a substrate dependent conjugation rate. A maximum likelihood based method is used to estimate the model parameters. Different models including different noise structure for the system and observations are compared......Conjugation is an important mechanism involved in the transfer of resistance between bacteria. In this article a stochastic differential equation based model consisting of a continuous time state equation and a discrete time measurement equation is introduced to model growth and conjugation of two...... using a likelihood-ratio test and Akaike's information criterion. Experiments indicating conjugation on the agar plates selecting for transconjugants motivates the introduction of an extended model, for which conjugation on the agar plate is described in the measurement equation. This model is compared...

Measurement of radionuclides in waste packages

Science.gov (United States)

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

1984-09-12

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

Poly(2-oxazoline)-Antibiotic Conjugates with Penicillins.

Science.gov (United States)

Schmidt, Martin; Bast, Livia K; Lanfer, Franziska; Richter, Lena; Hennes, Elisabeth; Seymen, Rana; Krumm, Christian; Tiller, Joerg C

2017-09-20

The conjugation of antibiotics with polymers is rarely done, but it might be a promising alternative to low-molecular-weight derivatization. The two penicillins penicillin G (PenG) and penicillin V (PenV) were attached to the end groups of different water-soluble poly(2-oxazoline)s (POx) via their carboxylic acid function. This ester group was shown to be more stable against hydrolysis than the β-lactam ring of the penicillins. The conjugates are still antimicrobially active and up to 20 times more stable against penicillinase catalyzed hydrolysis. The antibiotic activity of the conjugates against Staphylococcus aureus in the presence of penicillinase is up to 350 times higher compared with the free antibiotics. Conjugates with a second antimicrobial function, a dodecyltrimethylammonium group (DDA-X), at the starting end of the PenG and PenV POx conjugates are more antimicrobially active than the conjugates without DDA-X and show high activity in the presence of penicillinase. For example, the conjugates DDA-X-PEtOx-PenG and DDA-X-PEtOx-PenV are 200 to 350 times more active against S. aureus in the presence of penicillinase and almost as effective as the penicillinase stable cloxacollin (Clox) under these conditions. These conjugates show even greater activity compared to cloxacollin without this enzyme present. Further, both conjugates kill Escherichia coli more effectively than PenG and Clox.

Speciation of radionuclides in the environment

International Nuclear Information System (INIS)

Gunten, H.R. von; Benes, P.

1994-02-01

Methods for the determination of the speciation of radionuclides in aerosols, in aquatic solutions, in sediments, soils and rocks are reviewed. At present, most of the results about speciation are deduced from model calculations, model experiments, and separation of species (forms) of radionuclides, e.g., by sequential extraction procedures. Methods of direct determination of speciation of radionuclides (e.g. by laser induced spectroscopy) are in general not yet sensitive enough for a measurement of the very low concentrations of radionuclides in the environment. The methodological part of this paper is followed by a review of the very abundant literature about speciation of important radionuclides in the environment, i.e. in the atmosphere, hydrosphere and lithosphere. The review does not include the biosphere. Literature up to spring 1993 is included (with a few more recent additions). (author)

Radionuclide transport in a single fissure

International Nuclear Information System (INIS)

Eriksen, T.E.

1983-01-01

Radionuclide migration have been studied in natural fissures orieted parallel to the axis of granite drill cores. A short pulse of the radionuclides solution was injected at one end of the fissure and the temporal change in radionuclide concentration of the eluate measured. After several hundred fissure volumes water had been pumped through the fissure following the radionuclide pulse the activity distribution on the fissure surfaces was measured. From the retardation of 152 Eu, 235 Np and 237 Pu it is concluded that these radionuclides are transported in the oxidation states Eu(III), Pu(IV) and Np(V). The distribution coefficients K sub (d) calculated from flow and activity distribution data on the basis of geometric surface area/volume ratios are of the same order as published K sub (d) values obtained from batch equilibrium experiments. (Author)

Measurement of anthropogenic radionuclides in the atmosphere with a radionuclide monitoring network for nuclear tests

International Nuclear Information System (INIS)

Yonezawa, Chushiro; Yamamoto, Yoichi

2011-01-01

A worldwide radionuclide monitoring network for nuclear tests has detected the anthropogenic radioactive materials released in the atmosphere due to the accident of the Fukushima Daiichi Nuclear Power Plant impacted by the Great East Japan Earthquake on March 11, 2011. After four months have passed since the accident occurred, most overseas stations do not detect the radionuclides of Fukushima origin any more. The Takasaki station in Japan, however, is still detecting them every day. This paper describes radionuclide monitoring stations and the network of them as part of the International Monitoring System (IMS) in the Comprehensive Nuclear Test Ban Treaty (CTBT), as well as the measurement results of radionuclide particulates and radioactive isotopes of xenon released from the Fukushima Daiichi Nuclear Power Plant with the monitoring network. (J.P.N.)

Radionuclide behavior in water saturated porous media: Diffusion and infiltration coupling of thermodynamically and kinetically controlled radionuclide water - mineral interactions

International Nuclear Information System (INIS)

Spasennykh, M.Yu.; Apps, J.A.

1995-05-01

A model is developed describing one dimensional radionuclide transport in porous media coupled with locally reversible radionuclide water-mineral exchange reactions and radioactive decay. Problems are considered in which radionuclide transport by diffusion and infiltration processes occur in cases where radionuclide water-solid interaction are kinetically and thermodynamically controlled. The limits of Sr-90 and Cs-137 migration are calculated over a wide range of the problem variables (infiltration velocity, distribution coefficients, and rate constants of water-mineral radionuclide exchange reactions)

A vector Wiener filter for dual-radionuclide imaging

International Nuclear Information System (INIS)

Links, J.M.; Prince, J.L.; Gupta, S.N.

1996-01-01

The routine use of a single radionuclide for patient imaging in nuclear medicine can be complemented by studies employing two tracers to examine two different processes in a single organ, most frequently by simultaneous imaging of both radionuclides in two different energy windows. In addition, simultaneous transmission/emission imaging with dual-radionuclides has been described, with one radionuclide used for the transmission study and a second for the emission study. There is thus currently considerable interest in dual-radionuclide imaging. A major problem with all dual-radionuclide imaging is the crosstalk between the two radionuclides. Such crosstalk frequently occurs, because scattered radiation from the higher energy radionuclide is detected in the lower energy window, and because the lower energy radionuclide may have higher energy emissions which are detected in the higher energy window. The authors have previously described the use of Fourier-based restoration filtering in single photon emission computed tomography (SPECT) and positron emission tomography (PET) to improve quantitative accuracy by designing a Wiener or other Fourier filter to partially restore the loss of contrast due to scatter and finite spatial resolution effects. The authors describe here the derivation and initial validation of an extension of such filtering for dual-radionuclide imaging that simultaneously (1) improves contrast in each radionuclide's direct image, (2) reduces image noise, and (3) reduces the crosstalk contribution from the other radionuclide. This filter is based on a vector version of the Wiener filter, which is shown to be superior [in the minimum mean square error (MMSE) sense] to the sequential application of separate crosstalk and restoration filters

Approximate error conjugation gradient minimization methods

Science.gov (United States)

Kallman, Jeffrey S

2013-05-21

In one embodiment, a method includes selecting a subset of rays from a set of all rays to use in an error calculation for a constrained conjugate gradient minimization problem, calculating an approximate error using the subset of rays, and calculating a minimum in a conjugate gradient direction based on the approximate error. In another embodiment, a system includes a processor for executing logic, logic for selecting a subset of rays from a set of all rays to use in an error calculation for a constrained conjugate gradient minimization problem, logic for calculating an approximate error using the subset of rays, and logic for calculating a minimum in a conjugate gradient direction based on the approximate error. In other embodiments, computer program products, methods, and systems are described capable of using approximate error in constrained conjugate gradient minimization problems.

Dynamic modelling of radionuclide uptake by Fukushima coastal biota - Dynamic modelling of radionuclide uptake by marine biota: application to Fukushima assessment

Energy Technology Data Exchange (ETDEWEB)

Vives i Batlle, Jordi [Belgian Nuclear Research Centre, Boeretang 200, 2400 Mol (Belgium)

2014-07-01

Radiological assessments to non-human marine biota are usually carried out by assuming that the activity concentration in an organism is proportional to the activity concentration in an adjacent volume of water, via a concentration factor (CF). It is also assumed that radionuclides in the water are in isotopic equilibrium with the sediments via a sediment distribution coefficient (K{sub d}). These assumptions are not valid in accidental situations where the biota and the sediments react with a time delay to large variations of activity concentration in seawater. A simple dynamic model was developed to factorise the dynamics of radionuclide uptake and turnover in biota and sediments, as determined by a balance between the residence time of radionuclides in seawater/sediments and the biological half-life of elimination in the biota. The model calculates activity concentration of {sup 131}I, {sup 134}Cs, {sup 137}Cs and {sup 90}Sr in seabed sediment, fish, crustaceans, molluscs and macro-algae from surrounding activity concentrations in seawater, with which to derive internal and external dose rates. A central element of this new model is the inclusion of sediment processes in dynamic transfer modelling. The model is adapted to include depletion of radionuclides adsorbed onto suspended particulates (particle scavenging), molecular diffusion, pore water mixing and bioturbation (modelled effectively as a diffusive process) represented by a simple set of differential equations that is coupled with the biological uptake/turnover processes. In this way, the model is capable of reproducing activity concentration in sediment to give a more realistic calculation of the external dose to biota compared with the simpler approach based on CF and K{sub d} values used in previous assessments. The model is applied to the assessment of the radiological impact of the Fukushima accident on marine biota in the early phase of the accident. It is shown that previous assessment of the

Radionuclides in Canada goose eggs

International Nuclear Information System (INIS)

Rickard, W.H.; Sweany, H.A.

1975-01-01

Low levels of radionuclides were measured in Canada goose eggs taken from deserted nests from Columbia River islands on the Energy Research and Development Administration's Hanford Reservation. Potassium-40, a naturally occurring radionuclide, was the most abundant radionuclide measured in egg contents and egg shell. Strontium-90 was incorporated into egg shells and cesium-137 into inner egg contents. Manganese-54, cobalt-60, and zinc-65 were more abundant in inner egg contents than in egg shell. Cerium-144 was detected in egg shell but not in inner shell

Sensors and Automated Analyzers for Radionuclides

International Nuclear Information System (INIS)

Grate, Jay W.; Egorov, Oleg B.

2003-01-01

The production of nuclear weapons materials has generated large quantities of nuclear waste and significant environmental contamination. We have developed new, rapid, automated methods for determination of radionuclides using sequential injection methodologies to automate extraction chromatographic separations, with on-line flow-through scintillation counting for real time detection. This work has progressed in two main areas: radionuclide sensors for water monitoring and automated radiochemical analyzers for monitoring nuclear waste processing operations. Radionuclide sensors have been developed that collect and concentrate radionuclides in preconcentrating minicolumns with dual functionality: chemical selectivity for radionuclide capture and scintillation for signal output. These sensors can detect pertechnetate to below regulatory levels and have been engineered into a prototype for field testing. A fully automated process monitor has been developed for total technetium in nuclear waste streams. This instrument performs sample acidification, speciation adjustment, separation and detection in fifteen minutes or less

Radionuclide deposition control

International Nuclear Information System (INIS)

1980-01-01

A method is described for controlling the deposition, on to the surfaces of reactor components, of the radionuclides manganese-54, cobalt-58 and cobalt-60 from a liquid stream containing the radionuclides. The method consists of disposing a getter material (nickel) in the liquid stream, and a non-getter material (tantalum, tungsten or molybdenum) as a coating on the surfaces where deposition is not desired. The process is described with special reference to its use in the coolant circuit in sodium cooled fast breeder reactors. (U.K.)

Preparation, structural analysis and bioactivity of ribonuclease A-albumin conjugate: tetra-conjugation or PEG as the linker.

Science.gov (United States)

Li, Chunju; Lin, Qixun; Wang, Jun; Shen, Lijuan; Ma, Guanghui; Su, Zhiguo; Hu, Tao

2012-12-31

Ribonuclease A (RNase A) is a therapeutic enzyme with cytotoxic action against tumor cells. Its clinical application is limited by the short half-life and insufficient stability. Conjugation of albumin can overcome the limitation, whereas dramatically decrease the enzymatic activity of RNase A. Here, three strategies were proposed to prepare the RNase A-bovine serum albumin (BSA) conjugates. R-SMCC-B (a conjugate of four RNase A attached with one BSA) and R-PEG-B (a mono-conjugate) were prepared using Sulfo-SMCC (a short bifunctional linker) and mal-PEG-NHS (a bifunctional PEG), respectively. Mal-PEG-NHS and hexadecylamine (HDA) were used to prepare the mono-conjugate, R-HDA-B, where HDA was adopted to bind BSA. The PEG linker can elongate the proximity between RNase A and BSA. In contrast, four RNase A were closely located on BSA in R-SMCC-B. R-SMCC-B showed the lowest K(m) and the highest relative enzymatic activity and k(cat)/K(m) in the three conjugates. Presumably, the tetravalent interaction of RNase A in R-SMCC-B can increase the binding affinity to its substrate. In addition, the slow release of BSA from R-HDA-B may increase the enzymatic activity of R-HDA-B. Our study is expected to provide strategies to develop protein-albumin conjugate with high therapeutic potential. Copyright © 2012 Elsevier B.V. All rights reserved.

Radionuclide transfer

International Nuclear Information System (INIS)

Gerber, G.B.

1993-01-01

The research project described here had the aim to obtain further information on the transfer of nuclides during pregnancy and lactation. The tests were carried out in mini-pigs and rats receiving unchanging doses of radionuclides with the food. The following findings were revealed for the elements examined: Fe, Se, Cs and Zn were characterized by very high transfer levels in the mother, infant and foetus. A substantial uptake by the mother alone was observed for Co, Ag and Mn. The uptake by the foetus and infant here was 1 to 10 times lower. A preferential concentration in certain tissues was seen for Sr and Tc; the thyroid levels of Tc were about equally high in mothers and infants, while Sr showed less accumulation in the maternal bone. The lanthanide group of substances (Ce, Eu and Gd as well as Y and Ru) were only taken up to a very limited extent. The uptake of the examined radionuclides (Fe, Co, Ag, Ce) with the food ingested was found here to be ten times greater in rats as compared to mini-pigs. This showed that great caution must be observed, if the behaviour of radionuclides in man is extrapolated from relevant data obtained in rodents. (orig./MG) [de

Radionuclides in the study of marine processes

International Nuclear Information System (INIS)

Kershaw, P.J.; Woodhead, D.S.

1991-01-01

For many years, the radioactive properties of the naturally occurring radionuclides have been used to determine their distributions in the marine environment and, more generally, to gain an understanding of the dynamic processes which control their behaviour in attaining these distributions. More recently the inputs from human activities of both natural and artificial (i.e. man-made) radionuclides have provided additional opportunities for the study of marine processes on local, regional and global scales. The primary objective of the symposium is to provide a forum for an open discussion of the insights concerning processes in the marine environment which can be gained from studies of radionuclide behaviour. Papers have been grouped within the following principal themes; the uses of radionuclides as tracers of water transport; scavenging and particulate transport processes in the oceans as deduced from radionuclide behaviour; processes in the seabed and radionuclides in biological systems. (Author)

Chemical speciation of radionuclides migrating in groundwaters

International Nuclear Information System (INIS)

Robertson, D.; Schilk, A.; Abel, K.; Lepel, E.; Thomas, C.; Pratt, S.; Cooper, E.; Hartwig, P.; Killey, R.

1994-04-01

In order to more accurately predict the rates and mechanisms of radionuclide migration from low-level waste disposal facilities via groundwater transport, ongoing studies are being conducted at field sites at Chalk River Laboratories to identify and characterize the chemical speciation of mobile, long-lived radionuclides migrating in groundwaters. Large-volume water sampling techniques are being utilized to separate and concentrate radionuclides into particular, cationic, anionic, and nonionic chemical forms. Most radionuclides are migrating as soluble, anionic species that appear to be predominantly organoradionuclide complexes. Laboratory studies utilizing anion exchange chromatography have separated several anionically complexed radionuclides, e.g., 60 Co and 106 Ru, into a number of specific compounds or groups of compounds. Further identification of the anionic organoradionuclide complexes is planned utilizing high resolution mass spectrometry. Large-volume ultra-filtration experiments are characterizing the particulate forms of radionuclides being transported in these groundwaters

Chemical de-conjugation for investigating the stability of small molecule drugs in antibody-drug conjugates.

Science.gov (United States)

Chen, Tao; Su, Dian; Gruenhagen, Jason; Gu, Christine; Li, Yi; Yehl, Peter; Chetwyn, Nik P; Medley, Colin D

2016-01-05

Antibody-drug conjugates (ADCs) offer new therapeutic options for advanced cancer patients through precision killing with fewer side effects. The stability and efficacy of ADCs are closely related, emphasizing the urgency and importance of gaining a comprehensive understanding of ADC stability. In this work, a chemical de-conjugation approach was developed to investigate the in-situ stability of the small molecule drug while it is conjugated to the antibody. This method involves chemical-mediated release of the small molecule drug from the ADC and subsequent characterization of the released small molecule drug by HPLC. The feasibility of this technique was demonstrated utilizing a model ADC containing a disulfide linker that is sensitive to the reducing environment within cancer cells. Five reducing agents were screened for use in de-conjugation; tris(2-carboxyethyl) phosphine (TCEP) was selected for further optimization due to its high efficiency and clean impurity profile. The optimized de-conjugation assay was shown to have excellent specificity and precision. More importantly, it was shown to be stability indicating, enabling the identification and quantification of the small molecule drug and its degradation products under different formulation pHs and storage temperatures. In summary, the chemical de-conjugation strategy demonstrated here offers a powerful tool to assess the in-situ stability of small molecule drugs on ADCs and the resulting information will shed light on ADC formulation/process development and storage condition selection. Copyright © 2015 Elsevier B.V. All rights reserved.

Mobility and Bioavailability of Radionuclides in Soils

International Nuclear Information System (INIS)

Iurian, A.; Olufemi Phaneuf, M.; Mabit, L.

2016-01-01

It is crucial to understand the behavior of radionuclides in the environment, their potential mobility and bioavailability related to long-term persistence, radiological hazards, and impact on human health. Such key information is used to develop strategies that support policy decisions. The environmental behavior of radionuclides depends on ecosystem characteristics. A given soil’s capacity to immobilize radionuclides has been proved to be the main factor responsible for their resulting activity concentrations in plants. The mobility and bioavailability of radionuclides in soils is complex, depending on clay-sized soil fraction, clay mineralogy, organic matter, cation exchange capacity, pH and quantities of competing cations. Moreover, plant species have different behaviors regarding radionuclide absorption depending on soil and plan characteristics

Radionuclides deposition over Antarctica

International Nuclear Information System (INIS)

Pourchet, M.; Magand, O.; Frezzotti, M.; Ekaykin, A.; Winther, J.-G.

2003-01-01

A detailed and comprehensive map of the distribution patterns for both natural and artificial radionuclides over Antarctica has been established. This work integrates the results of several decades of international programs focusing on the analysis of natural and artificial radionuclides in snow and ice cores from this polar region. The mean value (37±20 Bq m -2 ) of 241 Pu total deposition over 28 stations is determined from the gamma emissions of its daughter 241 Am, presenting a long half-life (432.7 yrs). Detailed profiles and distributions of 241 Pu in ice cores make it possible to clearly distinguish between the atmospheric thermonuclear tests of the fifties and sixties. Strong relationships are also found between radionuclide data ( 137 Cs with respect to 241 Pu and 210 Pb with respect to 137 Cs), make it possible to estimate the total deposition or natural fluxes of these radionuclides. Total deposition of 137 Cs over Antarctica is estimated at 760 TBq, based on results from the 90-180 deg. East sector. Given the irregular distribution of sampling sites, more ice cores and snow samples must be analyzed in other sectors of Antarctica to check the validity of this figure

Radionuclides in the food chain

International Nuclear Information System (INIS)

Harley, J.H.; Schmidt, G.D.

1988-01-01

Radionuclides in the Food Chain reviews past experience in meeting the challenge of radionuclide contamination of foodstuffs and water sources and, in the wake of the reactor accidents at Chernobyl and Three Mile Island, presents current concepts and programs relating to measurement, surveillance, effects, risk management, evaluation guidelines, and control and regulatory activities. This volume, based on a symposium sponsored by the International Life Sciences Institute in association with the International Institute for Applied Systems Analysis, which brought together both radiation experts and food industry policymakers, examines such vital topics as structural problems in large-scale crisis-managment systems; dose assessment from man-made sources; international recommendations on radiation protection; airborne contamination, as well as aquatic and soilborne radionuclides; food-chain contamination from testing nuclear devices; long-term health effects of radionuclides in food and water supplies; and use of mathematical models in risk assessment and management. (orig.)

Idaho radionuclide exposure study: Literature review

International Nuclear Information System (INIS)

Baker, E.G.; Freeman, H.D.; Hartley, J.N.

1987-10-01

Phosphate ores contain elevated levels of natural radioactivity, some of which is released to the environment during processing or use of solid byproducts. The effect of radionuclides from Idaho phosphate processing operations on the local communities has been the subject of much research and study. The literature is reviewed in this report. Two primary radionuclide pathways to the environment have been studied in detail: (1) airborne release of volatile radionuclides, primarily 210 Po, from calciner stacks at the two elemental phosphorus plants; and (2) use of byproduct slag as an aggregate for construction in Soda Springs and Pocatello. Despite the research, there is still no clear understanding of the population dose from radionuclide emissions, effluents, and solid wastes from phosphate processing plants. Two other potential radionuclide pathways to the environment have been identified: radon exhalation from phosphogypsum and ore piles and contamination of surface and ground waters. Recommendations on further study needed to develop a data base for a complete risk assssment are given in the report

Photoluminescence in conjugated polymers

International Nuclear Information System (INIS)

Furst, J.E.; Laugesen, R.; Dastoor, P.; McNeill, C.

2002-01-01

Full text: Conjugated polymers combine the electronic and optical properties of semiconductors with the processability of polymers. They contain a sequence of alternate single and double carbon bonds so that the overlap of unhybridised p z orbitals creates a delocalised ρ system which gives semiconducting properties with p-bonding (valence) and p* -antibonding (conduction) bands. Photoluminesence (PL) in conjugated polymers results from the radiative decay of singlet excitons confined to a single chain. The present work is the first in a series of studies in our laboratory that will characterize the optical properties of conjugated polymers. The experiment involves the illumination of thin films of conjugated polymer with UV light (I=360 nm) and observing the subsequent fluorescence using a custom-built, fluorescence spectrometer. Photoluminesence spectra provide basic information about the structure of the polymer film. A typical spectrum is shown in the accompanying figure. The position of the first peak is related to the polymer chain length and resolved multiple vibronic peaks are an indication of film structure and morphology. We will also present results related to the optical degradation of these materials when exposed to air and UV light

Bio-Conjugates for Nanoscale Applications

DEFF Research Database (Denmark)

Villadsen, Klaus

Bio-conjugates for Nanoscale Applications is the title of this thesis, which covers three different projects in chemical bio-conjugation research, namely synthesis and applications of: Lipidated fluorescent peptides, carbohydrate oxime-azide linkers and N-aryl O-R2 oxyamine derivatives. Lipidated...

Some parameters of radionuclide kinetics

International Nuclear Information System (INIS)

Prokof'ev, O.N.; Smirnov, V.A.; Belen'kij, E.I.

1978-01-01

Numerical values of the rates of radionuclide absorption into, and elimination from, bovine organs were determined. Kinetic rate constants of radionuclides such as 89 Sr, 99 Mo, 131 I, 132 Tl, and 140 Be were calculated. The calculations were done for muscle, liver, and kidney

Radionuclide - Soil Organic Matter Interactions

DEFF Research Database (Denmark)

Carlsen, Lars

1985-01-01

Interactions between soil organic matter, i.e. humic and fulvic acids, and radionuclides of primary interest to shallow land burial of low activity solid waste have been reviewed and to some extent studied experimentally. The radionuclides considered in the present study comprise cesium, strontium...

Radionuclide transport in a single fissure

International Nuclear Information System (INIS)

Eriksen, T.E.

1984-01-01

Radionuclide migration has been studied in natural fissures running parallel to the axes of granitic drill cores. A short pulse of radionuclide solution was injected at one end of the fissure and the temporal change in radionuclide concentration of the eluate measured. At the end of each experiment the fissure was opened and the radionuclide distribution on the fissure surfaces measured. The retardation of 241 Am(III) at pH 8.2 as well as the variation in 235 Np(V) retardation with pH are found to be in good agreement with K d-values obtained in batch experiments. The reduction of (TcO - 4 ) to Tc(IV) leads as expected to increasing retardation.(author)

Radionuclide migration in water reservoirs

International Nuclear Information System (INIS)

Rodionova, L.F.

1983-01-01

Toxicity degree and radiation effect of different radionuclides depend on multiple factors, whose interaction can strengthen or weaken the effects through the mechanism of nuclide accumulation by hydrobiontes. Stage of development of an aquatic organism, its age, mass and sex as well as lifetime and residence time of the organism in the given medium are of importance. The radionuclide build up depends on illumination, locale of the bioobject residence, on the residence nature. The concentration of radionuclides in aquatic organisms and bionts survival depend on a season, temperature of the residence medium, as well as salinity and mineral composition of water influence

Interplay of alternative conjugated pathways and steric interactions on the electronic and optical properties of donor-acceptor conjugated polymers

KAUST Repository

Lima, Igo T.; Risko, Chad; Aziz, Saadullah Gary; Da Silva Filho, Demé trio A Da Silva; Bredas, Jean-Luc

2014-01-01

Donor-acceptor π-conjugated copolymers are of interest for a wide range of electronic applications, including field-effect transistors and solar cells. Here, we present a density functional theory (DFT) study of the impact of varying the conjugation pathway on the geometric, electronic, and optical properties of donor-acceptor systems. We consider both linear ("in series"), traditional conjugation among the donor-acceptor moieties versus structures where the acceptor units are appended orthogonally to the linear, donor-only conjugated backbone. Long-range-corrected hybrid functionals are used in the investigation with the values of the tuned long-range separation parameters providing an estimate of the extent of conjugation as a function of the oligomer architecture. Considerable differences in the electronic and optical properties are determined as a function of the nature of the conjugation pathway, features that should be taken into account in the design of donor-acceptor copolymers.

Radionuclide Air Emissions Report for 2012

Energy Technology Data Exchange (ETDEWEB)

Wahl, Linnea [Ernest Orlando Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States)

2013-05-01

Berkeley Lab operates facilities where radionuclides are produced, handled, store d, and potentially emitted . These facilities are subject to the EPA radioactive air emission regulations in 40 CFR 61, Subpart H (EPA 1989a). Radionuclides may be emitted from stacks or vents on buildings where radionuclide production or use is authorized or they may be emitted as diffuse sources. In 2012, all Berkeley Lab sources were minor sources of radionuclides (sources resulting in a potential dose of less than 0.1 mrem/yr [0.001 mSv/yr]) . These minor sources include d about 140 stack sources and no diffuse sources . T here were no unplanned airborne radionuclide emissions from Berkeley Lab operations . Emissions from minor sources were measured by sampling or monitoring or were calculated based on quantities used, received for use, or produced during the year. Using measured and calculated emissions, and building- specific and common parameters, Laboratory personnel applied the EPA -approved computer code s, CAP88-PC and COMPLY , to calculate doses to the maximally exposed individual (MEI) at any offsite point where there is a residence, school, business, or office. Because radionuclides are used at three noncontiguous locations (the main site, Berkeley West Bio center, and Joint BioEnergy Institute), three different MEIs were identified.

Molecular Targets for Targeted Radionuclide Therapy

International Nuclear Information System (INIS)

Mather, S.J.

2009-01-01

Molecular targeted radionuclide cancer therapy is becoming of increasing importance, especially for disseminated diseases. Systemic chemotherapies often lack selectivity while targeted radionuclide therapy has important advantages as the radioactive cytotoxic unit of the targeting vector is specifically directed to the cancer, sparing normal tissues. The principle strategy to improve cancer selectivity is to couple therapeutic agents to tumour-targeting vectors. In targeted radionuclide therapy (TRT), the cytotoxic portion of the conjugates normally contains a therapeutic radiometal immobilised by a bifunctional chelator. The aim is therefore to use as ligand-targeted therapeutics vectors coupled to Auger-, alpha- and/or beta-emitting radionuclides. An advantage of using radiation instead of chemotherapeutics as the cytotoxic agent is the so called 'crossfire effect'. This allows sterilisation of tumour cells that are not directly targeted due to heterogeneity in target molecule expression or inhomogeneous vector delivery. However, before the targeting ligands can be selected, the target molecule on the tumour has to be selected. It should be uniquely expressed, or at least highly overexpressed, on or in the target cells relative to normal tissues. The target should be easily accessible for ligand delivery and should not be shed or down- regulated after ligand binding. An important property of a receptor (or antigen) is its potential to be internalized upon binding of the ligand. This provides an active uptake mechanism and allows the therapeutic agent to be trapped within the tumour cells. Molecular targets of current interest include: Receptors: G-protein coupled receptors are overexpressed on many major human tumours. The prototype of these receptors are somatostatin receptors which show very high density in neuroendocrine tumours, but there are many other most interesting receptors to be applied for TRT. The targeting ligands for these receptors are

Radionuclide supply of the progeny via mother's milk

International Nuclear Information System (INIS)

Ovcharenko, E.P.

1982-01-01

While examining transition of radioactive substances from material organism to milk and then radionuclide administration with milk to progeny, a number of relationships had been revealed. They are similar to those discovered by the author during his study on transplacental radionuclide kinetics. The quantity of transition through placental and milk barriers of group 2 Periodical system radionuclides is inversally proportional to radionuclide mass number. There is evidence for the increase of radionuclide transition per different kinds of animal progeny mass unit during pregnancy as well as during lactation [ru

Radionuclide Retention in Concrete Wasteforms

Energy Technology Data Exchange (ETDEWEB)

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

2011-09-30

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

Water, soil, crops and radionuclides. Studies on the behavior of radionuclides in the terrestrial environments

International Nuclear Information System (INIS)

Uchida, Shigeo

2008-01-01

In order to predict the migration of artificially-produced radionuclides into a human body and its radiation dose rates of human body and to decrease the exposed radiation doses of human body, the behavior of radionuclides in the environment must be elucidated. In National Institute of Radiological Sciences (NIRS), the environmental radioecological research group of Nakaminato Laboratory for Marine Radioecology has progressed the survey and research on the behavior of artificially-produced radionuclides in the terrestrial environment. This article describes the research results (the radioactivity of water, soil, and crops) made so far at Nakaminato Laboratory for Marine Radioecology. (M.H.)

Country report: Cuba. Local Production of {sup 90}Y And {sup 188}Re Radionuclides and Development of Radiopharmaceuticals for Therapy

Energy Technology Data Exchange (ETDEWEB)

Xiques, Abmel; Hernández, Ignacio; Leyva, René; Pérez, Marylaine; Alonso, Luis Michel; Zamora, Minelys [Centro de Isotopos (CENTIS) (Cuba)

2010-07-01

During the first period of this CRP we could test an efficient and reliable generator system based on ion-chromatography to obtain {sup 90}Y from its parent radionuclide {sup 90}Sr. This production scheme for {sup 90}Y was outlined in the previous CRP related with the development of generator technologies. Quality parameters such as trace metals that can potentially interfere in the labeling of biomoléculas, {sup 90}Y recovery, {sup 90}Sr/{sup 90}Y ratio and radiation dose to bed matrix were evaluated. The results showed that high recovery and radionuclidic purity could be obtained for {sup 90}Y during its repeated separation from the {sup 90}Sr cow. No replacement or treatment of the cow were necessary and low waste generation and {sup 90}Sr losses less that 0.1% after each run were also observed during the present study. A Fab’ fragment was enzimatically produced and purified from the monoclonal antibody h-R3 (Nimotuzumab®). The fragment and the parent antibody were successfully conjugated with DOTA and labeled with {sup 90}Y. The radioinmunoconjugate thus obtained also exhibited a good 24 h in-vitro stability in an excess of DTPA. A {sup 90}Y radiocoloid was prepared in a cromic phosphate particle for radiosynoviorthesis with promising results in animal models. Two alumina based {sup 188}W/{sup 188}Re generators were prepared and their eluates were used in the labeling of hR3-DOTA conjugates. Quality control and in vivo evaluation in comparison with {sup 99m}Tc-hR3 showed very good results and similar pattern of distribution and pharmacokinetic and will be used in clinical trials for cancer patients. (author)

Abscess detection with radionuclides

International Nuclear Information System (INIS)

Alavi, J.B.

1988-01-01

Radionuclide studies may aid in the diagnosis and localization of intra-abdominal infections. Despite the introduction of new radiographic and ultrasound methods, there are several clinical situations in which radionuclide scans have proved useful. Those include detection of postoperative intra-abdominal abscess, evaluation of liver abscess, differentiation between pancreatic pseudocyst or abscess, evaluation of fever of unknown origin, and evaluation of inflammatory bowel disease. Each clinical situation is discussed separately here

Identification of Ambiguous Activities in Radionuclide Cisternography Using SPECT/CT: Aspirated and Ingested CSF Rhinorrhea

Energy Technology Data Exchange (ETDEWEB)

Lee, Dong Yun; Kim, Jae Seung [Univ. of Ulsan College of Medicine, Ulsan (Korea, Republic of)

2014-03-15

A 2 year-old little girl underwent Tc-99m diethylenthriamine pentaacetic acid (DTPA) radionuclide cisternography to evaluate CSF rhinorrhea (Fig. 1). Cisternography clearly showed consecutive tracer activity in the nasal cavity and nasal tip, reflecting cerebrospinal fluid (CSF) leakage. However, several unexpected activities appeared on the bilateral mid- and unilateral lower thorax on delayed images, respectively. We performed additional SPECT/CT to delineate the CSF leakage tract and identify the unexpected activities. Through SPECT/CT, we could confirm that the mid-thoracic activity was in the lung parenchyma, while the lower thoracic activity was in the stomach. Thus, we speculated that these unexpected activities were the result of aspirated and ingested CSF rhinorrhea. CSF rhinorrhea occurs when there is a fistula between the dura mater and the skull base and discharge of CSF from the nose. A spinal fluid leak from the intracranial space to the nasal respiratory tract is potentially very serious because of the risk of an ascending infection that could produce fulminant meningitis. Therefore, identification of the fistulous tract is helpful for patient management. Radionuclide cisternography is an important imaging modality to detect the site of leakage in patients with CSF rhinorrhea. The combination of radionuclide cistenography and SPECT/CT has led to a major improvement in the diagnostic accuracy for localization of CSF leakage. This case also shows an important role for SPECT/CT fusion imaging in radionuclide cisternography not only for localizing the primary CSF fistula tract, but also for evaluating ambiguous radiotracer activities in planar imaging; these ultimately turned out to be aspirated and ingested CSF rhinorrhea.

Identification of Ambiguous Activities in Radionuclide Cisternography Using SPECT/CT: Aspirated and Ingested CSF Rhinorrhea

International Nuclear Information System (INIS)

Lee, Dong Yun; Kim, Jae Seung

2014-01-01

A 2 year-old little girl underwent Tc-99m diethylenthriamine pentaacetic acid (DTPA) radionuclide cisternography to evaluate CSF rhinorrhea (Fig. 1). Cisternography clearly showed consecutive tracer activity in the nasal cavity and nasal tip, reflecting cerebrospinal fluid (CSF) leakage. However, several unexpected activities appeared on the bilateral mid- and unilateral lower thorax on delayed images, respectively. We performed additional SPECT/CT to delineate the CSF leakage tract and identify the unexpected activities. Through SPECT/CT, we could confirm that the mid-thoracic activity was in the lung parenchyma, while the lower thoracic activity was in the stomach. Thus, we speculated that these unexpected activities were the result of aspirated and ingested CSF rhinorrhea. CSF rhinorrhea occurs when there is a fistula between the dura mater and the skull base and discharge of CSF from the nose. A spinal fluid leak from the intracranial space to the nasal respiratory tract is potentially very serious because of the risk of an ascending infection that could produce fulminant meningitis. Therefore, identification of the fistulous tract is helpful for patient management. Radionuclide cisternography is an important imaging modality to detect the site of leakage in patients with CSF rhinorrhea. The combination of radionuclide cistenography and SPECT/CT has led to a major improvement in the diagnostic accuracy for localization of CSF leakage. This case also shows an important role for SPECT/CT fusion imaging in radionuclide cisternography not only for localizing the primary CSF fistula tract, but also for evaluating ambiguous radiotracer activities in planar imaging; these ultimately turned out to be aspirated and ingested CSF rhinorrhea

Organometallic B12-DNA conjugate

DEFF Research Database (Denmark)

Hunger, Miriam; Mutti, Elena; Rieder, Alexander

2014-01-01

Design, synthesis, and structural characterization of a B12-octadecanucleotide are presented herein, a new organometallic B12-DNA conjugate. In such covalent conjugates, the natural B12 moiety may be a versatile vector for controlled in vivo delivery of oligonucleotides to cellular targets in hum...

The Conjugate Acid-Base Chart.

Science.gov (United States)

Treptow, Richard S.

1986-01-01

Discusses the difficulties that beginning chemistry students have in understanding acid-base chemistry. Describes the use of conjugate acid-base charts in helping students visualize the conjugate relationship. Addresses chart construction, metal ions, buffers and pH titrations, and the organic functional groups and nonaqueous solvents. (TW)

Natural and Synthetic Barriers to Immobilize Radionuclides

International Nuclear Information System (INIS)

Um, W.

2011-01-01

The experiments of weathering of glass waste form and the reacted sediments with simulated glass leachates show that radionuclide sequestration can be significantly enhanced by promoting the formation of secondary precipitates. In addition, synthetic phosphate-bearing nanoporous material exhibits high stability at temperature and has a very high K d value for U(VI) removal. Both natural and synthetic barrier materials can be used as additional efficient adsorbents for retarding transport of radionuclides for various contaminated waste streams and waste forms present at U. S. Department of Energy clean-up sites and the proposed geologic radioactive waste disposal facility. In the radioactive waste repository facility, natural or synthetic materials are planned to be used as a barrier material to immobilize and retard radionuclide release. The getter material can be used to selectively scavenge the radionuclide of interest from a liquid waste stream and subsequently incorporate the loaded getters in a cementitious or various monolithic waste forms. Also, the getter material is to reduce the release of radionuclides from monolithic waste forms. Also, the getter material is to reduce the release of radionuclides from monolithic waste forms. Also, the getter material is to reduce the release of radionuclides form monolithic waste forms by being emplaced as a backfill barrier material around the wastes or waste form to minimize the potential around the wastes or waste form to minimize the potential hazard of leached radioactive wastes. The barrier material should be highly efficient to sequester radionuclides and possess physical and chemical stability for long-term exposure to severe weathering conditions. Because potential leaching of radionuclides depends on various environmental and weathering conditions of the near-field repository, the barrier materials must be durable and not disintegrate under a range of moisture, temperature, pressure, radiation, Eh, ph. and

Therapy for incorporated radionuclides: scope and need

International Nuclear Information System (INIS)

Smith, V.H.

1981-03-01

In the United States the recent termination of funding for research on therapy for incorporated radionuclides has virtually halted progress on improved or new agents and procedures for removing radioactivity from the body. Research was eliminated, but is still needed on new removal agents, improved delivery system, in vitro test systems, and the toxicology of treatments. For many radionuclides, no adequate therapy exists. The relationship between radionuclide removal and reduction in cancer risk is still unanswered. Without proper research support, needed improvements in the treatment for incorporated radionuclides in the US are uncertain

Phytoremediation of soils contaminated with radionuclides

International Nuclear Information System (INIS)

Yamaguchi, Isamu

2004-01-01

Aiming at efficient phytoremediation of soils contaminated with radionuclides, we examined the effect of soil microbes on the uptake ability of plants using the multitracer technique to find that tomato rhizofungi in Fusarium spp. can stimulate the uptake of 85 Sr and 137 Cs by the plants. The synergic effect of a nonpathogenic strain of F. oxysporum on the uptake of radionuclides by plants proved to be enhanced by introducing a phytochelatin synthase gene into the fungus. Since soil contamination by radionuclides is still an unsolved problem in many parts of the world. Studies on phytoremediation of polluted soil environment will be important for developing effective strategies and devising adequate techniques to reduce human risks caused by food contamination of radionuclides. (author)

REVIEW ARTICLE Conjugated Hyperbilirubinaemia in Early Infancy ...

African Journals Online (AJOL)

REVIEW ARTICLE Conjugated Hyperbilirubinaemia in Early Infancy. AOK Johnson. Abstract. Conjugated hyperbilirubinaemia exists when the conjugated serum bilirubin level is more than 2 mg/dl or more than 20 per cent of the total serum bilirubin. It is always pathological in early infancy. The causes are many and diverse ...

National Low-Level Waste Management Program Radionuclide Report Series

International Nuclear Information System (INIS)

Rudin, M.J.; Garcia, R.S.

1992-02-01

This volume serves as an introduction to the National Low-Level Radioactive Waste Management Program Radionuclide Report Series. This report includes discussions of radionuclides listed in Title 10 of the Code of Federal Regulations Part 61.55, Tables 1 and 2 (including alpha-emitting transuranics with half-lives greater than five years). Each report includes information regarding radiological and chemical characteristics of specific radionuclides. Information is also included discussing waste streams and waste forms that may contain each radionuclide, and radionuclide behavior in the environment and in the human body. Not all radionuclides commonly found at low-level radioactive waste sites are included in this report. The discussion in this volume explains the rationale of the radionuclide selection process

Effect of Chelator Conjugation Level and Injection Dose on Tumor and Organ Uptake of 111In Labeled MORAb-009, an Anti-mesothelin Antibody

Science.gov (United States)

Shin, I. S.; Lee, S.-M.; Kim, H. S.; Yao, Z.; Regino, C.; Sato, N.; Cheng, K. T.; Hassan, R.; Campo, M. F.; Albone, E. F.; Choyke, P. L.; Pastan, I.; Paik, C. H.

2012-01-01

Introduction Radiolabeling of a monoclonal antibody (mAb) with a metallic radionuclide requires the conjugation of a bifunctional chelator to the mAb. The conjugation, however, can alter the physical and immunological properties of the mAb, consequently affecting its tumor targeting pharmacokinetics. In this study, we investigated the effect of the amount of 2-(p-isothiocyanatobenzyl)-cyclohexyl-diethylenetriamine-pentaacetic acid (CHX-A″) conjugated to MORAb-009, a mAb directed against mesothelin and the effect of MORAb dose on the biodistribution of 111In labeled MORAb-009. Methods We used nude mice bearing A431/K5 tumor as a mesothelin-positive tumor model and A431 tumor as a mesothelin-negative control. To find the optimal level of CHX-A″ conjugation, CHX-A″-MORAb-009 conjugates with 2.4, 3.5, and 5.5 CHX-A″ molecules were investigated. To investigate the effect of injected MORAb-009 dose on neutralizing the shed-mesothelin in the circulation, the biodistribution studies were performed after the i.v. co-injection of the 111In labeled MORAb-009 (2.4 CHX-A″/MORAb-009) with three different doses, 0.2, 2, and 30 μg of MORAb-009. Results The tumor uptake in A431/K5 tumor was 4 times higher than that in A431 tumor, indicating that the tumor uptake in A431/K5 was mesothelin-mediated. The conjugate with 5.5 CHX-A″ showed a lower isoelectric point (pI) and lower immunoreactivity (IR) than the 2.4 CHX-A″ conjugate. These differences were reflected in biodistribution of the 111In label. The 111In labeled MORAb-009 conjugated with 2.4 CHX-A″ produced higher tumor uptake, and lower liver and spleen uptakes than the 5.5 CHX-A″ conjugate. The biodistribution studies also revealed that the tumor uptake was significantly affected by the injected MORAb-009 dose and tumor size. The 30 μg dose produced higher tumor uptake than the 0.2 and 2 μg doses whereas the 30 μg dose produced lower liver and spleen uptakes than the 0.2 μg dose. Conclusion This study

Radionuclide Retention in Concrete Waste Forms

Energy Technology Data Exchange (ETDEWEB)

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

2010-09-30

Assessing long-term performance of Category 3 waste cement grouts for radionuclide encasement requires knowledge of the radionuclide-cement interactions and mechanisms of retention (i.e., sorption or precipitation); the mechanism of contaminant release; the significance of contaminant release pathways; how waste form performance is affected by the full range of environmental conditions within the disposal facility; the process of waste form aging under conditions that are representative of processes occurring in response to changing environmental conditions within the disposal facility; the effect of waste form aging on chemical, physical, and radiological properties; and the associated impact on contaminant release. This knowledge will enable accurate prediction of radionuclide fate when the waste forms come in contact with groundwater. The information presented in the report provides data that 1) quantify radionuclide retention within concrete waste form materials similar to those used to encapsulate waste in the Low-Level Waste Burial Grounds (LLBG); 2) measure the effect of concrete waste form properties likely to influence radionuclide migration; and 3) quantify the stability of uranium-bearing solid phases of limited solubility in concrete.

Long-term development of the radionuclide exposure of murine rodent populations in Belarus after the Chernobyl accident.

Science.gov (United States)

Ryabokon, N I; Smolich, I I; Kudryashov, V P; Goncharova, R I

2005-12-01

external gamma-ray dose rate, but there were exceptions due to the delayed maximum of internal exposure. The inter-individual distributions of radionuclide concentrations and lifetime whole-body absorbed doses were asymmetric and close to log-normal, including concentrations and doses considerably higher than the population mean values.

Application of optical phase conjugation to plasma diagnostics (invited)

International Nuclear Information System (INIS)

Jahoda, F.C.; Anderson, B.T.; Forman, P.R.; Weber, P.G.

1985-01-01

Several possibilities for plasma diagnostics provided by optical phase conjugation and, in particular, self-pumped phase conjugation in barium titanate (BaTiO 3 ) are discussed. These include placing a plasma within a dye laser cavity equipped with a phase conjugate mirror for intracavity absorption measurements, time differential refractometry with high spatial resolution, and simplified real-time holographic interferometry. The principles of phase conjugation with particular reference to photorefractive media and the special advantages of self-pumped phase conjugation are reviewed prior to the discussion of the applications. Distinctions are made in the applications between those for which photorefractive conjugators are essential and those for which they only offer experimental simplification relative to other types of phase conjugators

Remediation of radionuclide pollutants through biosorption - an overview

Energy Technology Data Exchange (ETDEWEB)

Das, Nilanjana [Environmental Biotechnology Division, School of Biosciences and Technology, VIT University, Vellore (India)

2012-01-15

The development of nuclear science and technology has led to the increase of nuclear wastes containing radionuclides to be released and disposed in the environment. Pollution caused by radionuclides is a serious problem throughout the world. To solve the problem, substantial research efforts have been directed worldwide to adopt sustainable technologies for the treatment of radionuclide containing wastes. Biosorption represents a technological innovation as well as a cost effective excellent remediation technology for cleaning up radionuclides from aqueous environment. A variety of biomaterials viz. algae, fungi, bacteria, plant biomass, etc. have been reported for radionuclide remediation with encouraging results. This paper reviews the achievements and current status of radionuclide remediation through biosorption which will provide insights into this research frontier. (Copyright copyright 2012 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

Radionuclide injury to the lung

International Nuclear Information System (INIS)

Dagle, G.E.; Sanders, C.L.

1984-01-01

Radionuclide injury to the lung has been studied in rats, hamsters, dogs, mice and baboons. Exposure of the lung to high dose levels of radionuclides produces a spectrum of progressively more severe functional and morphological changes, ranging from radiation pneumonitis and fibrosis to lung tumors. These changes are somewhat similar for different species. Their severity can be related to the absorbed radiation dose (measured in rads) produced by alpha, beta or gamma radiation emanating from various deposited radionuclides. The chemicophysical forms of radionuclides and spatial-temporal factors are also important variables. As with other forms of injury to the lung, repair attempts are highlighted by fibrosis and proliferation of pulmonary epithelium. Lung tumors are the principal late effect observed in experimental animals following pulmonary deposition of radionuclides at dose levels that do not result in early deaths from radiation pneumonitis or fibrosis. The predominant lung tumors described have been of epithelial origin and have been classified, in decreasing frequency of occurrence, as adenocarcinoma, bronchioloalveolar carcinoma, epidermoid carcinomas and combined epidermoid and adenocarcinoma. Mesothelioma and fibrosarcoma have been observed in rats, but less commonly in other species. Hemangiosarcomas were frequently observed in dogs exposed to beta-gamma emitters, and occasionally in rats exposed to alpha emitters. These morphologic changes in the lungs of experimental animals were reviewed and issues relevant to the prediction of human hazards discussed. 88 references

Radionuclide lymphoscintigraphy in the evaluation of peripheral edema

International Nuclear Information System (INIS)

Kim, Soon; Zeon, Seok Kil

2000-01-01

It has been difficulty to visualize lymphatics in living patients. Conventional or direct lymphography has been the gold standard for delineation of the lymphatic system, but this procedure is invasive, difficulty to perform, and harmful to the lymphatic vascular endothelium. The aim of our study was to determine its severity, and to understand the drainage patterns on patients with peripheral edema by functional lymphatic studies. Tc-99m antimony sulfide colloid 25 MBq with 0.4 ml volume was injected intradermally in the first, second and third web space of the foot or hand in 40 patients with peripheral edema (5 in upper extremity and 35 in lower extremity). Initial flow after injection and whole body images at approximately 30 minutes. 1-4 hours were obtained. In 9/40 cases with peripheral edema normal lymphoscintigram were revealed, primary lymphedema was observed in 5/31 cases. The imaging patterns in primary lymphedema were absent (3 cases) or delayed (2 cases) transport, lymphatic duct dilatation (1), cutoff (1), decrease in size and number of lymph nodes (2). The Common caused of edema in secondry lymphedema (26/31) were carcinoma (13), inflammation (5), post-operation (5), and unknown origin (3). The common imaging findings in carcinoma showed non-visualization of lymph nodes (13), dermal backflow (8), collateral circulation (5), and in inflammation lymphatic obstruction (2), increase in size and number of lymph nodes (2), delayed transport (1), and in post-operation dermal backflow (3), delayed transport (2), decrease in number and size of lymph node (2) Clear images patterns were observed difference between primary lymphedema an secondary lymphedema. Radionuclide lymphoscintigraphy is essentially non-invasive, easy to perform repeatedly, and harmless to the lymphatic vascular endothelium for evaluation of a patient with lymphedema

The vertical distribution of radionuclides in a Ribble Estuary saltmarsh: transport and deposition of radionuclides

International Nuclear Information System (INIS)

Brown, J.E.; McDonald, P.; Parker, A.; Rae, J.E.

1999-01-01

Routine discharges of low-level liquid radioactive waste by British Nuclear Fuels plc (BNFL) at Sellafield and Springfields have resulted in enhanced levels of radionuclides in sediments of the Ribble Estuary, NW England, UK. Variations in radionuclide concentrations ( 137 Cs, 230 Th, and 239240 Pu) with depth in a mature saltmarsh core were analysed in order to investigate historical discharge trends and waste-dispersal mechanisms. Core samples from Longton/Hutton Marsh were analysed by gamma-spectrometry and α-spectrometry for radionuclides and by laser granulometry to establish grain-size variations with depth. Distinct subsurface maxima were present for 137 Cs and 239240 Pu with activities as high as 4500 Bq kg -1 for 137 Cs and 600 Bq kg -1 for 239240 Pu. Thorium-230 exhibited complex activity profiles with depth, specific activities ranging between 200 and 2400 Bq kg -1 . The vertical distributions of Sellafield-derived radionuclides ( 137 Cs and 239240 Pu) in mature saltmarsh deposits reflect the time-integrated discharge pattern from Sellafield, implying a transport mechanism that has involved the mixing of sediment labelled with radioactivity from recent discharges and sediment labelled from historical discharge events before deposition. A mechanism involving the transport of contaminated silt therefore seems to dominate. The vertical distribution of Springfields-derived 230 Th in the same areas reflects the annual gross-α discharge pattern from BNFL Springfields. In contrast to the Sellafield-derived radionuclides, a fairly rapid transport mechanism from source to sink is implied, with little or no time for mixing with radionuclides discharged years earlier. (Copyright (c) 1999 Elsevier Science B.V., Amsterdam. All rights reserved.)

Interpretation of biological-rate coefficients derived from radionuclide content, radionuclide concentration and specific activity experiments

International Nuclear Information System (INIS)

Vanderploeg, H.A.; Booth, R.S.

1976-01-01

Rigorous expressions are derived for the biological-rate coefficients (BRCs) determined from time-dependent measurements of three different dependent variables of radionuclide tracer experiments. These variables, which apply to a single organism, are radionuclide content, radionuclide concentration and specific activity. The BRCs derived from these variables have different mathematical expressions and, for high growth rates, their numerical values can be quite different. The precise mathematical expressions for the BRCs are presented here to aid modelers in selecting the correct parameters for their models and to aid experiments in interpreting their results. The usefulness of these three variables in quantifying elemental uptakes and losses by organisms is discussed. (U.K.)

Research on sorption behavior of radionuclides under shallow land environment. Mechanism and standard methodologies for measurement of distribution coefficients of radionuclides

International Nuclear Information System (INIS)

Sakamoto, Yoshiaki; Tanaka, Tadao; Takebe, Shinichi; Nagao, Seiya; Ogawa, Hiromichi; Komiya, Tomokazu; Hagiwara, Shigeru

2001-01-01

This study consists of two categories' research works. One is research on sorption mechanism of radionuclides with long half-life, which are Technetium-99, TRU elements and U series radionuclides, on soil and rocks, including a development of database of distribution coefficients of radionuclides. The database on the distribution coefficients of radionuclides with information about measurement conditions, such as shaking method, soil characteristics and solution composition, has been already opened to the public (JAERI-DATABASE 20001003). Another study is investigation on a standard methodology of the distribution coefficient of radionuclide on soils, rocks and engineering materials in Japan. (author)

Radionuclides in the environment: Risks and opportunities

International Nuclear Information System (INIS)

Elzerman, A.W.

1993-01-01

Environmental chemistry plays a critical role in the open-quotes nuclear ageclose quotes. It makes a vital contribution to understanding of the sources, fate and effects of radionuclides in the environment, both man-made and natural. Risk assessment of radionuclides in the environment relies heavily on the tools of environmental chemistry. On the other hand, radionuclides provide unique opportunities to exploit in environmental chemistry investigations due to their well-defined sources, traceability in environmental processes, analytical sensitivities, and open-quotes built-inclose quotes radioactive decay open-quotes clocksclose quotes. In some cases naturally present radionuclides are utilized, while in others tracers are deliberately added or have already been added by the nuclear fuel cycle or nuclear testing. Several examples in each of these categories are discussed to spotlight the current status of environmental chemistry and radionuclides in the environment as an example application

RIVER-RAD, Radionuclide Transport in Surface Waters

International Nuclear Information System (INIS)

1996-01-01

1 - Description of program or function: RIVER-RAD assesses the potential fate of radionuclides released to rivers. The model is simplified in nature and is intended to provide guidance in determining the potential importance of the surface water pathway, relevant transport mechanisms, and key radionuclides in estimating radiological dose to man. 2 - Method of solution: A compartmental linear transfer model is used in RIVER-RAD. The river system model in the code is divided into reaches (compartments) of equal size, each with a sediment compartment below it. The movement of radionuclides is represented by a series of transfers between the reaches, and between the water and sediment compartments of each reach. Within each reach (for both the water and sediment compartments), the radionuclides are assumed to be uniformly mixed. Upward volatilization is allowed from the water compartment, and the transfer of radionuclides between the reaches is determined by the flow rate of the river. Settling and resuspension velocities determine the transfer of absorbed radionuclides between the water and sediment compartments. Radioactive decay and decay-product buildup are incorporated into all transport calculations for all radionuclide chains specified by the user. Each nuclide may have unique input and removal rates. Volatilization and radiological decay are considered as linear rate constants in the model. 3 - Restrictions on the complexity of the problem: None noted

EBS Radionuclide Transport Abstraction

International Nuclear Information System (INIS)

Schreiner, R.

2001-01-01

The purpose of this work is to develop the Engineered Barrier System (EBS) radionuclide transport abstraction model, as directed by a written development plan (CRWMS M and O 1999a). This abstraction is the conceptual model that will be used to determine the rate of release of radionuclides from the EBS to the unsaturated zone (UZ) in the total system performance assessment-license application (TSPA-LA). In particular, this model will be used to quantify the time-dependent radionuclide releases from a failed waste package (WP) and their subsequent transport through the EBS to the emplacement drift wall/UZ interface. The development of this conceptual model will allow Performance Assessment Operations (PAO) and its Engineered Barrier Performance Department to provide a more detailed and complete EBS flow and transport abstraction. The results from this conceptual model will allow PA0 to address portions of the key technical issues (KTIs) presented in three NRC Issue Resolution Status Reports (IRSRs): (1) the Evolution of the Near-Field Environment (ENFE), Revision 2 (NRC 1999a), (2) the Container Life and Source Term (CLST), Revision 2 (NRC 1999b), and (3) the Thermal Effects on Flow (TEF), Revision 1 (NRC 1998). The conceptual model for flow and transport in the EBS will be referred to as the ''EBS RT Abstraction'' in this analysis/modeling report (AMR). The scope of this abstraction and report is limited to flow and transport processes. More specifically, this AMR does not discuss elements of the TSPA-SR and TSPA-LA that relate to the EBS but are discussed in other AMRs. These elements include corrosion processes, radionuclide solubility limits, waste form dissolution rates and concentrations of colloidal particles that are generally represented as boundary conditions or input parameters for the EBS RT Abstraction. In effect, this AMR provides the algorithms for transporting radionuclides using the flow geometry and radionuclide concentrations determined by other

Charged particle induced delayed X-rays (DEX) for the analysis of intermediate and heavy elements

Science.gov (United States)

Pillay, A. E.; Erasmus, C. S.; Andeweg, A. H.; Sellschop, J. P. F.; Annegarn, H. J.; Dunn, J.

1988-12-01

The emission of K X-rays from proton-rich and metastable radionuclides, following proton activation of the stable isotopes of the elements of interest, has not been widely used as a means of analysis. The thrust of this paper proposes a nuclear technique using delayed X-rays for the analysis of low concentrations of intermediate and heavy elements. The method is similar to the delayed gamma-ray technique. Proton bombardment induces mainly (p, n) reactions whereas the delayed X-rays originate largely from e --capture and isomeric transition. Samples of rare earth and platinum group elements (PGE), in the form of compacted powders, were irradiated with an 11 MeV proton beam and delayed X-rays detected with a 100 mm 2 Ge detector. Single element spectra for a range of rare earths and PGEs are presented. Analytical conditions are demonstrated for Pd in the range 0.1-5%. Spectra from actual geological samples of a PGE ore, preconcentrated by fire-assay, and monazite are presented. All six platinum group elements are visible and interference-free in a single spectrum, a marked advance on other nuclear techniques for these elements, including PIXE and neutron activation analysis (NAA).

Radionuclide carrier

International Nuclear Information System (INIS)

Hartman, F.A.; Kretschmar, H.C.; Tofe, A.J.

1978-01-01

A physiologically acceptable particulate radionuclide carrier is described. It comprises a modified anionic starch derivative with 0.1% to 1.5% by weight of a reducing agent and 1 to 20% by weight of anionic substituents

Chapter 13. Radionuclides in medicine

International Nuclear Information System (INIS)

Toelgyessy, J.; Harangozo, M.

2000-01-01

This is a chapter of textbook of radioecology for university students. In this chapter authors deal with problems connected with using of radionuclides in medicine. Methods of treatment with using of radionuclides are reviewed. Chapter consists of next parts: (1) Remotion of thyroid gland; (2) Treatment of cerebrally tumour in nuclear reactor; (3) Artificial heart

Naturally occurring radionuclides in food

International Nuclear Information System (INIS)

Djujic, I.

1995-01-01

The naturally occurring radionuclides are the major source of radiation exposure to humans. The principal way of natural radiation exposure is the inhalation of 222 Rn decay products (about 85% of the total). The remainder is equally divided between internally deposited radionuclides, cosmic and terrestrial sources. In the present study, the content of 40 K, 210 Pb, 226 Ra, 230 Th, 232 Th and 238 U in representative food samples (milk, pork, beef, potatoes, wheat and corn flour) and samples of different food items that do not represent entire national production but provide interesting additional data for approximative calculation of naturally occurring radionuclide intake is presented. Daily weight of food eaten, participation of food groups, as well as daily intake by food of mentioned naturally occurring radionuclides in the Serbian diet was obtained on the base of house hold budget surveys. The result obtained for daily intake estimates in mBq for Serbian population are 78.1 ( 40 K), 38.2( 210 Pb), 52.3( 226 Ra), 2.0( 230 Th) and 12.5( 238 U). (author)

Radionuclide Sensors for Subsurface Water Monitoring. Final report

International Nuclear Information System (INIS)

Timothy DeVol

2006-01-01

Contamination of the subsurface by radionuclides is a persistent and vexing problem for the Department of Energy. These radionuclides must be measured in field studies and monitored in the long term when they cannot be removed. However, no radionuclide sensors existed for groundwater monitoring prior to this team's research under the EMSP program. Detection of a and b decays from radionuclides in water is difficult due to their short ranges in condensed media

Uptake by plants of radionuclides from FUSRAP waste materials

International Nuclear Information System (INIS)

Knight, M.J.

1983-04-01

Radionuclides from FUSRAP wastes potentially may be taken up by plants during remedial action activities and permanent near-surface burial of contaminated materials. In order to better understand the propensity of radionuclides to accumulate in plant tissue, soil and plant factors influencing the uptake and accumulation of radionuclides by plants are reviewed. In addition, data describing the uptake of the principal radionuclides present in FUSRAP wastes (uranium-238, thorium-230, radium-226, lead-210, and polonium-210) are summarized. All five radionuclides can accumulate in plant root tissue to some extent, and there is potential for the translocation and accumulation of these radionuclides in plant shoot tissue. Of these five radionuclides, radium-226 appears to have the greatest potential for translocation and accumulation in plant shoot tissue. 28 references, 1 figure, 3 tables

Uptake by plants of radionuclides from FUSRAP waste materials

Energy Technology Data Exchange (ETDEWEB)

Knight, M.J.

1983-04-01

Radionuclides from FUSRAP wastes potentially may be taken up by plants during remedial action activities and permanent near-surface burial of contaminated materials. In order to better understand the propensity of radionuclides to accumulate in plant tissue, soil and plant factors influencing the uptake and accumulation of radionuclides by plants are reviewed. In addition, data describing the uptake of the principal radionuclides present in FUSRAP wastes (uranium-238, thorium-230, radium-226, lead-210, and polonium-210) are summarized. All five radionuclides can accumulate in plant root tissue to some extent, and there is potential for the translocation and accumulation of these radionuclides in plant shoot tissue. Of these five radionuclides, radium-226 appears to have the greatest potential for translocation and accumulation in plant shoot tissue. 28 references, 1 figure, 3 tables.

Determination of natural occurring radionuclides concentrations

International Nuclear Information System (INIS)

Stajic, J.; Markovic, V.; Krstic, D.; Nikezic, D.

2011-01-01

Tobacco smoke contains certain concentrations of naturally occurring radionuclides from radioactive chains of uranium and thorium - 214 Pb, 214 Bi, 228 Ac, 208 Tl, 226 Ra, 232 Th and 40 K. Inhaling of tobacco smoke leads to internal exposure of man. In order to estimate absorbed dose of irradiation it is necessary to determine concentrations of radionuclides present in the tobacco leaves. In this paper specific activities of naturally occurring radionuclides were measured in tobacco samples from cigarettes which are used in Serbia. [sr

Manual of bioassay procedures for radionuclides

International Nuclear Information System (INIS)

Pleskach, S.; Petkau, A.

1986-06-01

A monitoring program is described by which atomic radiation workers ar monitored for internal contamination with radionuclides in the workplace. The program involves analytical procedures for measuring alpha, beta and gamma activity in biological specimens, usually urine. Radionuclides are identified by their characteristic radiation using liquid scintillation counting, and alpha, beta and gamma spectrometry. Examples of calculating the minimum detectable activity for specific radionuclides are given and used to derive call-in-criteria in accordance with which the different groups of workers are monitored each month

Radionuclides in ground-level air

International Nuclear Information System (INIS)

Sinkko, K.

1987-01-01

In the air surveillance programme the concentrations of artificial radionuclides are monitored in the air close to the ground to obtain the necessary basic data for estimating the exposure of the Finnish population to fall-out radionuclides and also to detect atmospheric traces of radioactive materials caused by their use or production. Airborne dust is collected on filters with high-volume air samplers and the concentrations of gamma-emitting radionuclides in the air are evaluated. In the first quarter of 1986 only long-lived cesium, caused by earlier atmospheric nuclear explosions was detected. The concentrations of cesium were very low. In January and March a small amount of short-lived, fresh fission and activation products were also observed

Methotrexate and epirubicin conjugates as potential antitumor drugs

Directory of Open Access Journals (Sweden)

Szymon Wojciech Kmiecik

2017-07-01

Full Text Available Introduction: The use of hybrid molecules has become one of the most significant approaches in new cytotoxic drug design. This study describes synthesis and characterization of conjugates consisting of two well-known and characterized chemotherapeutic agents: methotrexate (MTX and epirubicin (EPR. The synthesized conjugates combine two significant anticancer strategies: combinatory therapy and targeted therapy. These two drugs were chosen because they have different mechanisms of action, which can increase the anticancer effect of the obtained conjugates. MTX, which is a folic acid analog, has high cytotoxic properties and can serve as a targeting moiety that can reach folate receptors (FRs overexpresing tumor cells. Combination of nonselective drugs such as EPR with MTX can increase the selectivity of the obtained conjugates, while maintaining the high cytotoxic properties.Materials and methods: Conjugates were purified by RP-HPLC and the structure was investigated by MS and MS/MS methods. The effect of the conjugates on proliferation of LoVo, LoVo/Dx, MCF-7 and MV-4-11 human cancer cell lines was determined by SRB or MTT assay.Results: The conjugation reaction results in the formation of monosubstituted (α, γ and disubstituted MTX derivatives. In vitro proliferation data demonstrate that the conjugates synthesized in our study show lower cytotoxic properties than both chemotherapeutics used alone.Discussion: Epirubicin cytotoxicity was not observed in obtained conjugates. Effective drugs release after internalization needs further investigation.

Modified inorganic nanoparticles as vehicles for alpha emitters in radionuclide therapy

International Nuclear Information System (INIS)

Piotrowska, A.; Leszczuk, E.; Koźmiński, P.; Bilewicz, A.; Morgenstern, A.; Bruchertseifer, F.

2014-01-01

The TiO 2 nanoparticles have unique properties like: high specific surface, high affinity for multivalent cations and simple way of synthesis, which are useful in the process of labelling. Commercially available (e.g. P-25 Degussa) and synthesised in our laboratory nanoparticles were used in experiments. The nanoparticles were characterized by TEM, SEM, DLS and NanoSight techniques. In the experiments, two different methods of labeling are tested. The first one was based on the possibility of formation strong bonds with certain cations on the surface of the nanoparticles. In the 65 second one, TiO 2 nanoparticles were doped with 225 Ac during the process of synthesis. In both cases, high yields of labelling (>99%) was obtained. Afterwards, the stability of labelled nanoparticles was examined in 0.9 % NaCl, 10 -3 M EDTA, solutions of biologically active substances (cysteine, glutathione) and human serum. In case of TiO 2 nanoparticles labelled with 225 Ac, which was built in the crystalline structure, the leakage of 225 Ac and its daughter radionuclides was not significant in any of solutions, even when the incubation time was extended to 10 days. In the case of nanoparticles with adsorbed 225 Ac on surface the leakage in serum was slightly higher, but still insignificant. Also the NaA nanozeolite as a carrier for radium radionuclides has been studied. 224 Ra and 225 Ra, the α-particle emitting radionuclides, have been absorbed in the nanometer-sized NaA zeolite through simple ion-exchange. 224,225 Ra-nanozeolites have shown very good stability in solutions containing: physiological salt, EDTA, amino acid and human serum. To make NaA nanozeolite particles dispersed in water their surface has been modified with silane coupling agent containing poly (ethylene glycol) (PEG) molecules. To obtain conjugates specific for receptors on glioma cancer cells short peptide substance P were covalently attached to the PEG-TiO 2 and PEG-nanozeolite surface. The obtained

Selected radionuclides important to low-level radioactive waste management

International Nuclear Information System (INIS)

1996-11-01

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

Selected radionuclides important to low-level radioactive waste management

Energy Technology Data Exchange (ETDEWEB)

NONE

1996-11-01

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

Measurements for modeling radionuclide transfer in the aquatic environment

International Nuclear Information System (INIS)

Kahn, B.

1976-01-01

Analytical methods for measuring radionuclides in the aquatic environment are discussed for samples of fresh water and seawater, fish and shellfish, biota such as algae, plankton, seaweed, and aquatic plants, and sediment. Consideration is given to radionuclide collection and concentration, sample preservation, radiochemical and instrumental analysis, and quality assurance. Major problems are the very low environmental levels of the radionuclides of interest, simultaneous occurrence of radionuclides in several chemical and physical forms and the numerous factors that affect radionuclide levels in and transfers among media. Some radionuclides of importance in liquid effluents from nuclear power stations are listed, and sources of radiochemical analytical methods are recommended

Statistical analysis of fallout radionuclides transfer to paddy-field rice

International Nuclear Information System (INIS)

Takahashi, T.; Morisawa, S.; Inoue, Y.

1996-01-01

Radionuclides released from nuclear facilities to atmosphere are transported through various pathways in biosphere and cause human exposure. Among these radionuclides transfer pathways, an ingestion of crops containing radionuclides is one of the dominant pathway for human exposure. For the safety assessment of nuclear facilities, it is important to understand the behavior of radionuclides in agricultural environment and to describe them in a mathematical model. In this paper, a statistical model is proposed for estimating the concentration of fallout radionuclides in paddy-field rice, the staple food for Japanese people. For describing behavior of fallout radionuclides in a paddy-field, a dynamic model and a statistical model have been proposed respectively. The model used in this study has been developed assuming that the amount of radionuclides transfer to brown rice (hulled rice) or polished rice through direct deposition of airborne radionuclides (the direct deposition pathway) and root uptake from a paddy soil (the root uptake pathway) are proportional to the deposition flux of radionuclides and concentration of radionuclides in paddy soil respectively. That is, the model has two independent variables; the deposition flux of radionuclides and the concentration of radionuclides in the paddy soil, and has single dependent variable; the concentration of radionuclides in brown rice or polished rice. The regression analysis is applied by using environmental monitoring data. Then the distribution of radionuclides between rice-bran (skin part of rice crop) and polished rice (core part) through both the direct deposition pathway and the root uptake pathway are evaluated by the model. (author)

Accumulation of radionuclides by lichen symbionts

Energy Technology Data Exchange (ETDEWEB)

Nifontova, M G; Kulikov, N V [AN SSSR, Sverdlovsk. Inst. Ehkologii Rastenij i Zhivotnykh

1983-01-01

The aim of investigation is the quantitative estimation of ability and role of separate symbionts in the accumulation of radionuclides. As investigation volumes, durably cultivated green lichen alga Trebouxia erici and lichen fungi extracted from Cladonia rangiferina, Parmelia caperata and Acarospora fuscata are used. The accumulation of radioactive isotopes with fungi and seaweeds is estimated according to accumulation coefficients (AC) which are the ratio of radiation concentration in plants and agarized medium. Radionuclide content (/sup 90/Sr and /sup 137/Cs) is determined radiometrically. A special series of experiments is done to investigate radionuclide accumulation dependences with lichen seaweed and fungi on light conditions. It is shown that both symbionts of lichen-seaweed and fungus take part in the accumulation of radionuclide from outer medium (atmospheric fall-out and soil). However fungus component constituting the base of structural organization of thallus provides the greater part of radionuclides accumulated by the plant. Along with this the violation of viability of seaweed symbionts particularly in the case of light deficiency brings about the reduction of /sup 137/Cs sorption by seaweeds and tells on the total content of radiocesium in plant thallus.

Targeted Radionuclide Therapy

Directory of Open Access Journals (Sweden)

David Cheng

2011-10-01

Full Text Available Targeted radiotherapy is an evolving and promising modality of cancer treatment. The killing of cancer cells is achieved with the use of biological vectors and appropriate radionuclides. Among the many advantages of this approach are its selectiveness in delivering the radiation to the target, relatively less severe and infrequent side effects, and the possibility of assessing the uptake by the tumor prior to the therapy. Several different radiopharmaceuticals are currently being used by various administration routes and targeting mechanisms. This article aims to briefly review the current status of targeted radiotherapy as well as to outline the advantages and disadvantages of radionuclides used for this purpose.

Targeted Radionuclide Therapy

Energy Technology Data Exchange (ETDEWEB)

Ersahin, Devrim, E-mail: devrimersahin@yahoo.com; Doddamane, Indukala; Cheng, David [Department of Diagnostic Radiology, School of Medicine, Yale University, 333 Cedar St., New Haven, CT 06520 (United States)

2011-10-11

Targeted radiotherapy is an evolving and promising modality of cancer treatment. The killing of cancer cells is achieved with the use of biological vectors and appropriate radionuclides. Among the many advantages of this approach are its selectiveness in delivering the radiation to the target, relatively less severe and infrequent side effects, and the possibility of assessing the uptake by the tumor prior to the therapy. Several different radiopharmaceuticals are currently being used by various administration routes and targeting mechanisms. This article aims to briefly review the current status of targeted radiotherapy as well as to outline the advantages and disadvantages of radionuclides used for this purpose.

Radionuclides in foods

International Nuclear Information System (INIS)

1994-01-01

This report contains data on the levels of radionuclides in the UK foodchain. Most data derive from monitoring programmes that exist around nuclear sites, and in some cases date back to the 1960s. Some comparative data from site operator and government-run programmes are included. Data from monitoring undertaken after the Chernobyl accident are summarised. General monitoring of the foodchain for both artificial and natural radionuclides, and the results of relevant government-sponsored research are also described. The report includes basic information on radioactivity in the environment, radiation protection standards and describes what measures are taken to routinely monitor the foodchain and assess public risk. (Author)

Targeted Radionuclide Therapy

International Nuclear Information System (INIS)

Ersahin, Devrim; Doddamane, Indukala; Cheng, David

2011-01-01

Targeted radiotherapy is an evolving and promising modality of cancer treatment. The killing of cancer cells is achieved with the use of biological vectors and appropriate radionuclides. Among the many advantages of this approach are its selectiveness in delivering the radiation to the target, relatively less severe and infrequent side effects, and the possibility of assessing the uptake by the tumor prior to the therapy. Several different radiopharmaceuticals are currently being used by various administration routes and targeting mechanisms. This article aims to briefly review the current status of targeted radiotherapy as well as to outline the advantages and disadvantages of radionuclides used for this purpose

Radionuclides in house dust

Energy Technology Data Exchange (ETDEWEB)

Fry, F A; Green, N; Dodd, N J; Hammond, D J

1985-04-01

Discharges of radionuclides from the British Nuclear Fuel plc (BNFL) reprocessing plant at Sellafield in Cumbria have led to elevated concentrations radionuclides in the local environment. The major routes of exposure of the public are kept under review by the appropriate authorising Government departments and monitoring is carried out both by the departments and by BNFL itself. Recently, there has been increasing public concern about general environmental contamination resulting from the discharges and, in particular, about possible exposure of members of the public by routes not previously investigated in detail. One such postulated route of exposure that has attracted the interest of the public, the press and Parliament arises from the presence of radionuclides within houses. In view of this obvious and widespread concern, the Board has undertaken a sampling programme in a few communities in Cumbria to assess the radiological significance of this source of exposure. From the results of our study, we conclude that, although radionuclides originating rom the BNFL site can be detected in house dust, this source of contamination is a negligible route of exposure for members of the public in West Cumbria. This report presents the results of the Board's study of house dust in twenty homes in Cumbria during the spring and summer of 1984. A more intensive investigation is being carried out by Imperial College. (author)

Radionuclide accumulation peculiarities demonstrated by vegetable varieties

International Nuclear Information System (INIS)

Kruk, A.V.; Goncharenko, G.G.; Kilchevsky, A.V.

2004-01-01

This study focused on ecological and genetic aspects of radionuclide accumulation demonstrated by a number of vegetable varieties. The researches resulted in determining the cabbage varieties which were characterised by the minimal level of radionuclide accumulation. It was shown that the above varieties manifested the relation between radionuclide accumulation and morphobiological characteristics such as vegetation period duration and yield criteria. The study specified the genotypes with high ecological stability as regards to radionuclide accumulation: 'Beloruskaya 85' cabbage and 'Dokhodny' tomato showed the best response to Cs 137, while 'Beloruskaya 85', 'Rusinovka', 'Amager 611' cabbage varieties and 'Sprint' tomato showed the minimal level of Sr 90 accumulation. (authors)

2008 LANL radionuclide air emissions report

Energy Technology Data Exchange (ETDEWEB)

Fuehne, David P.

2009-06-01

The emissions of radionuclides from Department of Energy Facilities such as Los Alamos National Laboratory (LANL) are regulated by the Amendments to the Clean Air Act of 1990, National Emissions Standards for Hazardous Air Pollutants (40 CFR 61 Subpart H). These regulations established an annual dose limit of 10 mrem to the maximally exposed member of the public attributable to emissions of radionuclides. This document describes the emissions of radionuclides from LANL and the dose calculations resulting from these emissions for calendar year 2008. This report meets the reporting requirements established in the regulations.

2010 LANL radionuclide air emissions report /

Energy Technology Data Exchange (ETDEWEB)

Fuehne, David P.

2011-06-01

The emissions of radionuclides from Department of Energy Facilities such as Los Alamos National Laboratory (LANL) are regulated by the Amendments to the Clean Air Act of 1990, National Emissions Standards for Hazardous Air Pollutants (40 CFR 61 Subpart H). These regulations established an annual dose limit of 10 mrem to the maximally exposed member of the public attributable to emissions of radionuclides. This document describes the emissions of radionuclides from LANL and the dose calculations resulting from these emissions for calendar year 2010. This report meets the reporting requirements established in the regulations.

Preparation of porous materials for radionuclides capture

International Nuclear Information System (INIS)

Bajzikova, Anna; Smrcek, Stanislav; Kozempel, Jan; Vlk, Martin; Barta, Jan

2015-01-01

Porous materials showing promise for radionuclide capture from water at contaminated sites were prepared. Nanoporous materials (size of pores 1-100 nm) and some polymers are well suited to this purpose owing their affinity for selected radionuclides. Nanoporous metal oxides and silica gel with styrene-divinylbenzene-TODGA-modified surface were prepared, characterized and tested for radionuclide ( 227 Ac, 227 Th, 223 Ra) capture efficiency. (orig.)

Radionuclide Data Centre. Tasks and problems of obtaining the most reliable values of the nuclear physics characteristics of radionuclides and radiation physics parameters of radionuclide sources

International Nuclear Information System (INIS)

Chechev, V.P.

1994-01-01

Information is provided on the establishment of the Radionuclide Data Centre under the V.G. Khlopin Radium Institute. Its functions and areas of activity are discussed. The paper focuses on the procedure of obtaining the evaluated values of the decay and radiative characteristics of the widely used radionuclides. (author)

TIMED: a computer program for calculating cumulated activity of a radionuclide in the organs of the human body at a given time, t, after deposition

International Nuclear Information System (INIS)

Watson, S.B.; Snyder, W.S.; Ford, M.R.

1976-12-01

TIMED is a computer program designed to calculate cumulated radioactivity in the various source organs at various times after radionuclide deposition. TIMED embodies a system of differential equations which describes activity transfer in the lungs, gastrointestinal tract, and other organs of the body. This system accounts for delay of transfer of activity between compartments of the body and radioactive daughters

Human dose pathways of radionuclides in forests

International Nuclear Information System (INIS)

Rantavaara, A.

2009-01-01

Forest soil, understorey vegetation and trees are all sources of radionuclides and human radiation doses after contaminating atmospheric deposition. People are exposed to radiation externally from sources outside the body and internally via ingestion and inhalation of radionuclides. Understorey vegetation contributes to ingestion doses through berries, herbs, wild honey, mushrooms and game meat; also trees provide feed to terrestrial birds and big game. During stay in forests people are subject to external radiation from forest floor and overstorey, and they may inhale airborne radioactive aerosol or gaseous radionuclides in ground level air. In the early phase of contamination also resuspended radionuclides may add to the internal dose of people via inhalation. People in Nordic countries are most exposed to radiation via ingestion of radionuclides in wild foods. The distribution of radionuclides in forests is changed by environmental processes, and thereby also the significance of various dose pathways to humans will change with time. External exposure is received in living environment from contaminated stemwood used as building timber and for manufacturing of furniture and other wood products. The aim of this paper is to outline the significance of various human dose pathways of radionuclides in forests considering the public and workers in forestry and production of bioenergy. Examples on effective doses are given based on two historical events, atmospheric nuclear weapon tests (mostly in 1950's and in 1960's) and the Chernobyl nuclear power plant accident in 1986. (au)

General program for the advancement of the radionuclide technology

International Nuclear Information System (INIS)

1979-12-01

The 'General Program for the Advancement of the Radionuclide Technology' was elaborated in 1978 by the 'Arbeitsgemeinschaft zur Foerderung der Radionuklidtechnik' (AFR) (Association for the Promotion of Radionuclide Technology). In addition to an inventory of the major applications of radionuclide technology, this General Program includes a comprehensive description of tasks relating to the central topics of raw materials, environment, technology and materials, health and nutrition, scientific developments of radionuclide technology. The 'General Program for the Advancement of the Radionuclide Technology' serves inter alia as a basis of evaluation in opinions on funding applications filed with the Federal Ministry for Research and Technology (BMFT) with respect to the provision of advanced techniques involving radionuclides for industrial application. (orig.) [de

Theoretical estimation of absorbed dose to organs in radioimmunotherapy using radionuclides with multiple unstable daughters

International Nuclear Information System (INIS)

Hamacher, K.A.; Sgouros, G.

2001-01-01

The toxicity and clinical utility of long-lived alpha emitters such as Ac-225 and Ra-223 will depend upon the fate of alpha-particle emitting unstable intermediates generated after decay of the conjugated parent. For example, decay of Ac-225 to a stable element yields four alpha particles and seven radionuclides. Each of these progeny has its own free-state biodistribution and characteristic half-life. Therefore, their inclusion for a more accurate prediction of absorbed dose and potential toxicity requires a formalism that takes these factors into consideration as well. To facilitate the incorporation of such intermediates into the dose calculation, a previously developed methodology (model 1) has been extended. Two new models (models 2 and 3) for allocation of daughter products are introduced and are compared with the previously developed model. Model 1 restricts the transport to a function that yields either the place of origin or the place(s) of biodistribution depending on the half-life of the parent radionuclide. Model 2 includes the transient time within the bloodstream and model 3 incorporates additional binding at or within the tumor. This means that model 2 also allows for radionuclide decay and further daughter production while moving from one location to the next and that model 3 relaxes the constraint that the residence time within the tumor is solely based on the half-life of the parent. The models are used to estimate normal organ absorbed doses for the following parent radionuclides: Ac-225, Pb-212, At-211, Ra-223, and Bi-213. Model simulations are for a 0.1 g rapidly accessible tumor and a 10 g solid tumor. Additionally, the effects of varying radiolabled carrier molecule purity and amount of carrier molecules, as well as tumor cell antigen saturation are examined. The results indicate that there is a distinct advantage in using parent radionuclides such as Ac-225 or Ra-223, each having a half-life of more than 10 days and yielding four alpha

Radionuclides in house dust

CERN Document Server

Fry, F A; Green, N; Hammond, D J

1985-01-01

Discharges of radionuclides from the British Nuclear Fuel plc (BNFL) reprocessing plant at Sellafield in Cumbria have led to elevated concentrations radionuclides in the local environment. The major routes of exposure of the public are kept under review by the appropriate Government departments and monitoring is carried out both by the departments and by BNFL itself. Recently, there has been increasing public concern about general environmental contamination resulting from the discharges and, in particular, about possible exposure of members of the public by routes not previously investigated in detail. One such postulated route of exposure that has attracted the interest of the public, the press and Parliament arises from the presence of radionuclides within houses. In view of this obvious and widespread concern, the Board has undertaken a sampling programme in a few communities in Cumbria to assess the radiological significance of this source of exposure. From the results of our study, we conclude that, alt...

Geochemistry and radionuclide migration

International Nuclear Information System (INIS)

Isherwood, D.

1978-01-01

Theoretically, the geochemical barrier can provide a major line of defense in protecting the biosphere from the hazards of nuclear waste. The most likely processes involved are easily identified. Preliminary investigations using computer modeling techniques suggest that retardation is an effective control on radionuclide concentrations. Ion exchange reactions slow radionuclide migration and allow more time for radioactive decay and dispersion. For some radionuclides, solubility alone may limit concentrations to less than the maximum permissible now considered acceptable by the Federal Government. The effectiveness of the geochemical barrier is ultimately related to the repository site characteristics. Theory alone tells us that geochemical controls will be most efficient in an environment that provides for maximum ion exchange and the precipitation of insoluble compounds. In site selection, consideration should be given to rock barriers with high ion exchange capacity that might also act as semi-permeable membranes. Also important in evaluating the site's potential for effective geochemical controls are the oxidation potentials, pH and salinity of the groundwater

Multivalent peptidic linker enables identification of preferred sites of conjugation for a potent thialanstatin antibody drug conjugate.

Directory of Open Access Journals (Sweden)

Sujiet Puthenveetil

Full Text Available Antibody drug conjugates (ADCs are no longer an unknown entity in the field of cancer therapy with the success of marketed ADCs like ADCETRIS and KADCYLA and numerous others advancing through clinical trials. The pursuit of novel cytotoxic payloads beyond the mictotubule inhibitors and DNA damaging agents has led us to the recent discovery of an mRNA splicing inhibitor, thailanstatin, as a potent ADC payload. In our previous work, we observed that the potency of this payload was uniquely tied to the method of conjugation, with lysine conjugates showing much superior potency as compared to cysteine conjugates. However, the ADC field is rapidly shifting towards site-specific ADCs due to their advantages in manufacturability, characterization and safety. In this work we report the identification of a highly efficacious site-specific thailanstatin ADC. The site of conjugation played a critical role on both the in vitro and in vivo potency of these ADCs. During the course of this study, we developed a novel methodology of loading a single site with multiple payloads using an in situ generated multi-drug carrying peptidic linker that allowed us to rapidly screen for optimal conjugation sites. Using this methodology, we were able to identify a double-cysteine mutant ADC delivering four-loaded thailanstatin that was very efficacious in a gastric cancer xenograft model at 3mg/kg and was also shown to be efficacious against T-DM1 resistant and MDR1 overexpressing tumor cell lines.

Multivalent peptidic linker enables identification of preferred sites of conjugation for a potent thialanstatin antibody drug conjugate.

Science.gov (United States)

Puthenveetil, Sujiet; He, Haiyin; Loganzo, Frank; Musto, Sylvia; Teske, Jesse; Green, Michael; Tan, Xingzhi; Hosselet, Christine; Lucas, Judy; Tumey, L Nathan; Sapra, Puja; Subramanyam, Chakrapani; O'Donnell, Christopher J; Graziani, Edmund I

2017-01-01

Antibody drug conjugates (ADCs) are no longer an unknown entity in the field of cancer therapy with the success of marketed ADCs like ADCETRIS and KADCYLA and numerous others advancing through clinical trials. The pursuit of novel cytotoxic payloads beyond the mictotubule inhibitors and DNA damaging agents has led us to the recent discovery of an mRNA splicing inhibitor, thailanstatin, as a potent ADC payload. In our previous work, we observed that the potency of this payload was uniquely tied to the method of conjugation, with lysine conjugates showing much superior potency as compared to cysteine conjugates. However, the ADC field is rapidly shifting towards site-specific ADCs due to their advantages in manufacturability, characterization and safety. In this work we report the identification of a highly efficacious site-specific thailanstatin ADC. The site of conjugation played a critical role on both the in vitro and in vivo potency of these ADCs. During the course of this study, we developed a novel methodology of loading a single site with multiple payloads using an in situ generated multi-drug carrying peptidic linker that allowed us to rapidly screen for optimal conjugation sites. Using this methodology, we were able to identify a double-cysteine mutant ADC delivering four-loaded thailanstatin that was very efficacious in a gastric cancer xenograft model at 3mg/kg and was also shown to be efficacious against T-DM1 resistant and MDR1 overexpressing tumor cell lines.

DKPRO: A radionuclide decay and reprocessing code

International Nuclear Information System (INIS)

Wootan, D.; Schmittroth, F.A.

1997-01-01

The DKPRO code solves the general problem of modeling complex nuclear wastes streams using ORIGEN2 radionuclide production files. There is a continuing need for estimates of Hanford radionuclides. Physical measurements are one basis; calculational estimates, the approach represented here, are another. Given a known nuclear fuel history, it is relatively straightforward to calculate radionuclide inventories with codes such as the widely-used Oak Ridge National Laboratory code ORIGEN2

Transfer of radionuclides into human milk

International Nuclear Information System (INIS)

Steiner, M.; Wirth, E.

1998-01-01

Up until now the potential radiation exposure to breast-fed babies due to contaminated human milk has not been taken into account, when deriving international limit values and reference levels for radionuclides in foodstuffs, in air at monitored work places or for exposures in the medical field. It was the aim of the research project 'Transfer of radionuclides into human milk' to quantify the transfer of incorporated radionuclides into mother's milk, and develop simple models to estimate the radiation exposure of babies through the ingestion of human milk. The study focused on considerations of the radiation exposure due to the ingestion of contaminated foodstuffs by the mother, the inhalation of radionuclides at monitored work places, and the administration of radiopharmaceuticals to breast-feeding mothers. The blocking of infant thyroid glands by stable iodine in the case of accidental releases of radioiodine was considered as well. (orig.) [de

Targeting of indium 111-labeled bivalent hapten to human melanoma mediated by bispecific monoclonal antibody conjugates: Imaging of tumors hosted in nude mice

International Nuclear Information System (INIS)

Le Doussal, J.M.; Gruaz-Guyon, A.; Martin, M.; Gautherot, E.; Delaage, M.; Barbet, J.

1990-01-01

Antibody conjugates were prepared by coupling F(ab')2 or Fab' fragments of an antibody specific for the human high molecular weight-melanoma associated antigen to Fab' fragments of an antibody specific for indium-diethylenetriaminepentaacetate complexes. Monovalent and bivalent haptens were synthesized by reacting the dipeptide tyrosyl-lysine with diethylenetriaminepentaacetic cyclic anhydride. In vitro, the antibody conjugate mediated binding of the 111In-labeled haptens to melanoma cells. In vivo, it allowed specific localization of the haptens in A375 tumors. The bivalent hapten exhibited much higher efficiency at targeting 111In onto cells, both in vitro and in vivo. Antibody conjugate and hapten doses (2 micrograms and 1 pmol, respectively) and the delay between antibody conjugate and tracer injections (24 h) were adjusted to maximize tumor uptake (4% injected dose/g) and tumor to normal tissue contrast (greater than 3) obtained 3 h after injection of the 111In-labeled bivalent hapten. This two-step technique, when compared to direct targeting of 111In-labeled F(ab')2 fragments, provided lower localization of injected activity into the tumor (x 0.25), but higher tumor/tissue ratios, especially with respect to liver (x 7), spleen (x 8), and kidneys (x 10). In addition, high contrast images were obtained within 3 hours, instead of days. Thus, antibody conjugate-mediated targeting of small bivalent haptens, labeled with short half-life isotopes, is proposed as a general method for improving tumor radioimmunolocalization

Radionuclide migration in crystalline rock fractures

International Nuclear Information System (INIS)

Hoelttae, P.

2002-01-01

Crystalline rock has been considered as a host medium for the repository of high radioactive spent nuclear fuel in Finland. The geosphere will act as an ultimate barrier retarding the migration of radionuclides to the biosphere if they are released through the technical barriers. Radionuclide transport is assumed to take place along watercarrying fractures, and retardation will occur both in the fracture and within the rock matrix. To be able to predict the transport and retardation of radionuclides in rock fractures and rock matrices, it is essential to understand the different phenomena involved. Matrix diffusion has been indicated to be an important mechanism, which will retard the transport of radionuclides in rock fractures. Both dispersion and matrix diffusion are processes, which can have similar influences on solute breakthrough curves in fractured crystalline rock. In this work, the migration of radionuclides in crystalline rock fractures was studied by means of laboratory scale column methods. The purpose of the research was to gain a better understanding of various phenomena - particularly matrix diffusion - affecting the transport and retardation behaviour of radionuclides in fracture flow. Interaction between radionuclides and the rock matrix was measured in order to test the compatibility of experimental retardation parameters and transport models used in assessing the safety of underground repositories for spent nuclear fuel. Rock samples of mica gneiss and of unaltered, moderately altered and strongly altered tonalite represented different rock features and porosities offering the possibility to determine experimental boundary limit values for parameters describing both the transport and retardation of radionuclides and rock matrix properties. The dominant matrix diffusion behaviour was demonstrated in porous ceramic column and gas diffusion experiments. Demonstration of the effects of matrix diffusion in crystalline rock fracture succeeded for the

In Vitro Evaluation of Third Generation PAMAM Dendrimer Conjugates

Directory of Open Access Journals (Sweden)

Mohammad Najlah

2017-10-01

Full Text Available The present study compares the use of high generation G3 and low generation G0 Polyamidoamine (PAMAM dendrimers as drug carriers of naproxen (NAP, a poorly water soluble drug. Naproxen was conjugated to G3 in different ratios and to G0 in a 1:1 ratio via a diethylene glycol linker. A lauroyl chain (L, a lipophilic permeability enhancer, was attached to G3 and G0 prodrugs. The G3 and G0 conjugates were more hydrophilic than naproxen as evaluated by the measurement of partitioning between 1-octanol and a phosphate buffer at pH 7.4 and pH 1.2. The unmodified surface PAMAM-NAP conjugates showed significant solubility enhancements of NAP at pH 1.2; however, with the number of NAP conjugated to G3, this was limited to 10 molecules. The lactate dehydrogenase (LDH assay indicated that the G3 dendrimer conjugates had a concentration dependent toxicity towards Caco-2 cells. Attaching naproxen to the surface of the dendrimer increased the IC50 of the resulting prodrugs towards Caco-2 cells. The lauroyl G3 conjugates showed the highest toxicity amongst the PAMAM dendrimer conjugates investigated and were significantly more toxic than the lauroyl-G0-naproxen conjugates. The permeability of naproxen across monolayers of Caco-2 cells was significantly increased by its conjugation to either G3 or G0 PAMAM dendrimers. Lauroyl-G0 conjugates displayed considerably lower cytotoxicity than G3 conjugates and may be preferable for use as a drug carrier for low soluble drugs such as naproxen.

Gastroesophageal reflux in children: radionuclide gastroesophagography

International Nuclear Information System (INIS)

Blumhagen, J.D.; Rudd, T.G.; Christie, D.L.

1980-01-01

Sixty-five symptomatic infants and children underwent radionuclide gastroesophagography, acid reflux testing, and barium esophagography with water-siphon testing to evaluate the clinical efficacy of the scintigraphic technique in detecting gastroesophageal reflux. After ingesting /sup 99m/Tc sulfur colloid in fruit juice, patients rested beneath the gamma camera for 30 to 60 min while esophageal activity was monitored continuously. By using the acid reflux test as a standard of comparison, the senstivity of radionuclide gastroesophagography was 75%. Because of its physiologic nature, low radiation exposure, and convenience, radionuclide gastroesophagography warrants further evaluation as a screening test for gastroesophageal reflux

Soil - plant experimental radionuclide transfer factors

International Nuclear Information System (INIS)

Dobrin, R.I.; Dulama, C.N.; Toma, Al.

2006-01-01

Some experimental research was performed in our institute to assess site specific soil-plant transfer factors. A full characterization of an experimental site was done both from pedo-chemical and radiological point of view. Afterwards, a certain number of culture plants were grown on this site and the evolution of their radionuclide burden was then recorded. Using some soil amendments one performed a parallel experiment and the radionuclide root uptake was evaluated and recorded. Hence, transfer parameters were calculated and some conclusions were drawn concerning the influence of site specific conditions on the root uptake of radionuclides. (authors)

Sources of anthropogenic radionuclides in the environment: a review

International Nuclear Information System (INIS)

Hu Qinhong; Weng Jianqing; Wang Jinsheng

2010-01-01

Studies of radionuclides in the environment have entered a new era with the renaissance of nuclear energy and associated fuel reprocessing, geological disposal of high-level nuclear wastes, and concerns about national security with respect to nuclear non-proliferation. This work presents an overview on sources of anthropogenic radionuclides in the environment, as well as a brief discussion of salient geochemical behavior of important radionuclides. We first discuss the following major anthropogenic sources and current developments that have lead, or could potentially contribute, to the radionuclide contamination of the environment: (1) nuclear weapons program; (2) nuclear weapons testing; (3) nuclear power plants; (4) uranium mining and milling; (5) commercial fuel reprocessing; (6) geological repository of high-level nuclear wastes that include radionuclides might be released in the future, and (7) nuclear accidents. Then, we briefly summarize the inventory of radionuclides 99 Tc and 129 I, as well as geochemical behavior for radionuclides 99 Tc, 129 I, and 237 Np, because of their complex geochemical behavior, long half-lives, and presumably high mobility in the environment; biogeochemical cycling and environment risk assessment must take into account speciation of these redox-sensitive radionuclides.

CONJUGATED BLOCK-COPOLYMERS FOR ELECTROLUMINESCENT DIODES

NARCIS (Netherlands)

Hilberer, A; Gill, R.E; Herrema, J.K; Malliaras, G.G; Wildeman, J.; Hadziioannou, G

In this article we review results obtained in our laboratory on the design and study of new light-emitting polymers. We are interested in the synthesis and characterisation of block copolymers with regularly alternating conjugated and non conjugated sequences. The blocks giving rise to luminescence

Tetrafullerene conjugates for all-organic photovoltaics

NARCIS (Netherlands)

Fernández, G.; Sánchez, L.; Veldman, D.; Wienk, M.M.; Atienza, C.M.; Guldi, D.M.; Janssen, R.A.J.; Martin, N.

2008-01-01

The synthesis of two new tetrafullerene nanoconjugates in which four C60 units are covalently connected through different -conjugated oligomers (oligo(p-phenylene ethynylene) and oligo(p-phenylene vinylene)) is described. The photovoltaic (PV) response of these C60-based conjugates was evaluated by

Transuranic radionuclides dispersed into the aquatic environment, a bibliography

Energy Technology Data Exchange (ETDEWEB)

Noshkin, V.E.; Stoker, A.C.; Wong, Kai M. [and others

1994-04-01

The purpose of this project was to compile a bibliography of references containing environmental transuranic radionuclide data. Our intent was to identify those parameters affecting transuranic radionuclide transport that may be generic and those that may be dependent on chemical form and/or environmental conditions (i.e., site specific) in terrestrial, aquatic and atmospheric environments An understanding of the unique characteristics and similarities between source terms and environmental conditions relative to transuranic radionuclide transport and cycling will provide the ability to assess and predict the long term impact on man and the environment. An additional goal of our literature review, was to extract the ranges of environmental transuranic radionuclide data from the identified references for inclusion in a data base. Related to source term, these ranges of data can be used to calculate the dose to man from the radionuclides, and to perform uncertainty analyses on these dose assessments. On the basis of our reviews, we have arbitrarily outlined five general source terms. These are fallout, fuel cycle waste, accidents, disposal sites and resuspension. Resuspension of the transuranic radionuclides is a unique source term, in that the radionuclides can originate from any of the other source terms. If these transuranic radionuclides become resuspended into the air, they then become important as a source of inhaled radionuclides.

Novel Aflatoxin Derivatives and Protein Conjugates

Directory of Open Access Journals (Sweden)

Reinhard Niessner

2007-03-01

Full Text Available Aflatoxins, a group of structurally related mycotoxins, are well known for their toxic and carcinogenic effects in humans and animals. Aflatoxin derivatives and protein conjugates are needed for diverse analytical applications. This work describes a reliable and fast synthesis of novel aflatoxin derivatives, purification by preparative HPLC and characterisation by ESI-MS and one- and two-dimensional NMR. Novel aflatoxin bovine serum albumin conjugates were prepared and characterised by UV absorption and MALDI-MS. These aflatoxin protein conjugates are potentially interesting as immunogens for the generation of aflatoxin selective antibodies with novel specificities.

Radionuclide characterization of environmental air around nuclear facilities

International Nuclear Information System (INIS)

Gede Sutresna Wijaya; Anung Muharini

2015-01-01

Air is an important environmental component in human life. Presence of air pollutants or contaminants will have a negative impact on human health. According to the existence of a nuclear facility in Yogyakarta, the characterization of radionuclides in the air is absolutely necessary to ensure the safety of people and the environment and also to supervise the safe operation of the facility. In this research the characterization of radionuclides in the air was carried through the air sampling by using High Volume Air Sampler equipped with filter TFA 2133, followed by analysis using combination of a gamma and alpha spectrometers. The concentration of radioactivity in the air fluctuates depending on the time and duration of sampling. Characterization of gamma emitting radionuclides in the air is dominated by radon progeny radionuclides such as 214 Pb, 214 Bi with activity 20.09 ± 1.23 until 32.91 ± 4.87 Bq/m 3 and 31.22 ± 1.76 until 44.25 ± 4.91 Bq/m 3 . Alpha emitter radionuclide was dominated by 214 Po (7.69 MeV) which is also radon progeny and a primordial radionuclides. It can be concluded that the presence of radionuclides in the environmental air not as a product resulting from the operation of nuclear facilities in Yogyakarta. (author)

An overview of BORIS: Bioavailability of Radionuclides in Soils

International Nuclear Information System (INIS)

Tamponnet, C.; Martin-Garin, A.; Gonze, M.-A.; Parekh, N.; Vallejo, R.; Sauras-Yera, T.; Casadesus, J.; Plassard, C.; Staunton, S.; Norden, M.; Avila, R.; Shaw, G.

2008-01-01

The ability to predict the consequences of an accidental release of radionuclides relies mainly on the level of understanding of the mechanisms involved in radionuclide interactions with different components of agricultural and natural ecosystems and their formalisation into predictive models. Numerous studies and databases on contaminated agricultural and natural areas have been obtained, but their use to enhance our prediction ability has been largely limited by their unresolved variability. Such variability seems to stem from incomplete knowledge about radionuclide interactions with the soil matrix, soil moisture, and biological elements in the soil and additional pollutants, which may be found in such soils. In the 5th European Framework Programme entitled Bioavailability of Radionuclides in Soils (BORIS), we investigated the role of the abiotic (soil components and soil structure) and biological elements (organic compounds, plants, mycorrhiza, and microbes) in radionuclide sorption/desorption in soils and radionuclide uptake/release by plants. Because of the importance of their radioisotopes, the bioavailability of three elements, caesium, strontium, and technetium has been followed. The role of one additional non-radioactive pollutant (copper) has been scrutinised in some cases. Role of microorganisms (e.g., K d for caesium and strontium in organic soils is much greater in the presence of microorganisms than in their absence), plant physiology (e.g., changes in plant physiology affect radionuclide uptake by plants), and the presence of mycorrhizal fungi (e.g., interferes with the uptake of radionuclides by plants) have been demonstrated. Knowledge acquired from these experiments has been incorporated into two mechanistic models CHEMFAST and BIORUR, specifically modelling radionuclide sorption/desorption from soil matrices and radionuclide uptake by/release from plants. These mechanistic models have been incorporated into an assessment model to enhance its

An overview of BORIS: Bioavailability of Radionuclides in Soils

Energy Technology Data Exchange (ETDEWEB)

Tamponnet, C. [Institute of Radioprotection and Nuclear Safety, DEI/SECRE, CADARACHE, B.P. 1, 13108 Saint-Paul-lez-Durance, Cedex (France)], E-mail: christian.tamponnet@irsn.fr; Martin-Garin, A.; Gonze, M.-A. [Institute of Radioprotection and Nuclear Safety, DEI/SECRE, CADARACHE, B.P. 1, 13108 Saint-Paul-lez-Durance, Cedex (France); Parekh, N. [Center for Ecology and Hydrology, Lancaster Environment Centre, Lancaster University, Lancaster LA1 4YQ (United Kingdom); Vallejo, R.; Sauras-Yera, T.; Casadesus, J. [Department of Plant Biology, University of Barcelona, 08028 Barcelona (Spain); Plassard, C.; Staunton, S. [INRA, UMR Rhizosphere and Symbiosis, Place Viala, 34060 Montpellier (France); Norden, M. [Swedish Radiation Protection Institute, 171 16 Stockholm (Sweden); Avila, R. [Facilia AB, Valsgaerdevaegen 12, 168 53 Bromma, Stockholm (Sweden); Shaw, G. [Division of Agricultural and Environmental Sciences University Park, Nottingham NG7 2RD (United Kingdom)

2008-05-15

The ability to predict the consequences of an accidental release of radionuclides relies mainly on the level of understanding of the mechanisms involved in radionuclide interactions with different components of agricultural and natural ecosystems and their formalisation into predictive models. Numerous studies and databases on contaminated agricultural and natural areas have been obtained, but their use to enhance our prediction ability has been largely limited by their unresolved variability. Such variability seems to stem from incomplete knowledge about radionuclide interactions with the soil matrix, soil moisture, and biological elements in the soil and additional pollutants, which may be found in such soils. In the 5th European Framework Programme entitled Bioavailability of Radionuclides in Soils (BORIS), we investigated the role of the abiotic (soil components and soil structure) and biological elements (organic compounds, plants, mycorrhiza, and microbes) in radionuclide sorption/desorption in soils and radionuclide uptake/release by plants. Because of the importance of their radioisotopes, the bioavailability of three elements, caesium, strontium, and technetium has been followed. The role of one additional non-radioactive pollutant (copper) has been scrutinised in some cases. Role of microorganisms (e.g., K{sub d} for caesium and strontium in organic soils is much greater in the presence of microorganisms than in their absence), plant physiology (e.g., changes in plant physiology affect radionuclide uptake by plants), and the presence of mycorrhizal fungi (e.g., interferes with the uptake of radionuclides by plants) have been demonstrated. Knowledge acquired from these experiments has been incorporated into two mechanistic models CHEMFAST and BIORUR, specifically modelling radionuclide sorption/desorption from soil matrices and radionuclide uptake by/release from plants. These mechanistic models have been incorporated into an assessment model to enhance

Structure Property Relationships in Organic Conjugated Systems

OpenAIRE

O'Neill, Luke

2008-01-01

A series of pi(п) conjugated oligomers containing 1 to 6 monomer units were studied by absorption and photoluminescence spectroscopies. The results are discussed and examined with regard to the variation of the optical properties with the increase of effective conjugation length. It was found that there was a linear relationship between the positioning of the absorption and photoluminescence maxima plotted against inverse conjugation length. The relationships are in good agreement with the si...

A basic toxicity classification of radionuclides

International Nuclear Information System (INIS)

1963-01-01

In the course of its work in the field of health and safety the International Atomic Energy Agency has often met the practical requirement for grading radionuclides in order of their relative radiotoxicities. This need was particularly evident when the Agency's Basic Safety Standards for the protection of health against ionizing radiation were in preparation, when it was necessary to exempt quantities of radionuclides from inclusion in the norms. A basic toxicity grading might be of help to laboratories in meeting some of their requirements in problems related to waste management as well as for the design of experimental facilities. It should also serve as a basis for the development of safety criteria for laboratory equipment and procedures for handling and transporting various quantities and kinds of radionuclides. The purpose of the present Report is to make a toxicity grading of the radionuclides according to the risk of biological injury which they may cause when they have become incorporated in the human body. 4 refs, 4 tabs

A basic toxicity classification of radionuclides

Energy Technology Data Exchange (ETDEWEB)

1963-04-01

In the course of its work in the field of health and safety the International Atomic Energy Agency has often met the practical requirement for grading radionuclides in order of their relative radiotoxicities. This need was particularly evident when the Agency's Basic Safety Standards for the protection of health against ionizing radiation were in preparation, when it was necessary to exempt quantities of radionuclides from inclusion in the norms. A basic toxicity grading might be of help to laboratories in meeting some of their requirements in problems related to waste management as well as for the design of experimental facilities. It should also serve as a basis for the development of safety criteria for laboratory equipment and procedures for handling and transporting various quantities and kinds of radionuclides. The purpose of the present Report is to make a toxicity grading of the radionuclides according to the risk of biological injury which they may cause when they have become incorporated in the human body. 4 refs, 4 tabs.

Method of preparing radionuclide doses

International Nuclear Information System (INIS)

Kuperus, J.H.

1987-01-01

A method is described of preparing aliquot dosea of a tracer material useful in diagnostic nuclear medicine comprising: storing discrete quantities of a lyophilized radionuclide carrier in separate tubular containers from which air and moisture is excluded, selecting from the tubular containers a container in which is stored a carrier appropriate for a nuclear diagnostic test to be performed, interposing the selected container between the needle and the barrel of a hypodermic syringe, and drawing a predetermined amount of a liquid containing a radionuclide tracer in known concentration into the hypodermic syringe barrel through the hypodermic needle and through the selected container to dissolve the discrete quantity of lyophilized carrier therein to combine the carrier with the radionuclide tracer to form an aliquot dose of nuclear diagnostic tracer material, as needed

Transfer parameters of radionuclides in the marine environment

International Nuclear Information System (INIS)

1996-03-01

To increase the accuracy of estimation of exposure dose by radionuclides in the marine, the informations of environmental parameter data in the marine were collected, arranged and discussed. The informations were discussed by 'a sectional committee of marine suspended solids and sediment'. The following problems were investigated and the studies were recorded in this report, clear explanation about the distribution factor (kd), the estimation method of kd, the fluctuating factor of kd data (properties of suspension and sediment, differences among the experimental methods), the physical and chemical behavior of radionuclides, sediment of radionuclides by means of sorption to the suspended particles in the marine, sorption of radionuclides into the marine soil (sediment), re-eluent of radionuclides sorpted in the marine soil (sediment), and relation between marine organism and marine suspended materials and sediment. (S.Y.)

Sources and Bioactive Properties of Conjugated Dietary Fatty Acids.

Science.gov (United States)

Hennessy, Alan A; Ross, Paul R; Fitzgerald, Gerald F; Stanton, Catherine

2016-04-01

The group of conjugated fatty acids known as conjugated linoleic acid (CLA) isomers have been extensively studied with regard to their bioactive potential in treating some of the most prominent human health malignancies. However, CLA isomers are not the only group of potentially bioactive conjugated fatty acids currently undergoing study. In this regard, isomers of conjugated α-linolenic acid, conjugated nonadecadienoic acid and conjugated eicosapentaenoic acid, to name but a few, have undergone experimental assessment. These studies have indicated many of these conjugated fatty acid isomers commonly possess anti-carcinogenic, anti-adipogenic, anti-inflammatory and immune modulating properties, a number of which will be discussed in this review. The mechanisms through which these bioactivities are mediated have not yet been fully elucidated. However, existing evidence indicates that these fatty acids may play a role in modulating the expression of several oncogenes, cell cycle regulators, and genes associated with energy metabolism. Despite such bioactive potential, interest in these conjugated fatty acids has remained low relative to the CLA isomers. This may be partly attributed to the relatively recent emergence of these fatty acids as bioactives, but also due to a lack of awareness regarding sources from which they can be produced. In this review, we will also highlight the common sources of these conjugated fatty acids, including plants, algae, microbes and chemosynthesis.

Preparation and immunological properties of procaine-protein conjugates

International Nuclear Information System (INIS)

Liakopoulou, A.

1981-01-01

Procaine was conjugated to BSA and rat and rabbit Gf using the carbodiimide method and 14 C-procaine as tracer. The composition of the conjugates could be varied depending on the time of incubation and the concentration of procaine in the reaction mixtures. Procaine-BSA conjugates were soluble in water or saline. However, procaine conjugates to rat or rabbit Gf were not readily soluble in saline. These conjugates were good for immunization purposes, but it was cumbersome to work with them when clear solutions were needed, as in the immunochemical procedures used in this study. The immunological properties of the conjugates were studied in rats and rabbits. Rats responded with production of IgGa and precipitating antibodies to the procaine group, but IgE antibodies to the immunogen could not be detected. Furthermore, precipitating antibodies towards the procaine group were raised in rabbits. When BSA was the protein carrier, antibodies to the carrier molecule were also detected in both rats and rabbits. The conjugates of procaine to rat or rabbit Gf did not elicit antibody response to the carrier molecule when used in the homologous species. Hapten inhibition studies suggested that, in the rabbit, antibodies were also produced with specificity directed towards the molecular configuration of the hapten-carrier bond. (author)

IRDye78 Conjugates for Near-Infrared Fluorescence Imaging

Directory of Open Access Journals (Sweden)

Atif Zaheer

2002-10-01

Full Text Available The detection of human malignancies by near-infrared (NIR fluorescence will require the conjugation of cancer-specific ligands to NIR fluorophores that have optimal photoproperties and pharmacokinetics. IRDye78, a tetra-sulfonated heptamethine indocyanine NIR fluorophore, meets most of the criteria for an in vivo imaging agent, and is available as an N-hydroxysuccinimide ester for conjugation to low-molecular-weight ligands. However, IRDye78 has a high charge-to-mass ratio, complicating purification of conjugates. It also has a potentially labile linkage between fluorophore and ligand. We have developed an ion-pairing purification strategy for IRDye78 that can be performed with a standard C18 column under neutral conditions, thus preserving the stability of fluorophore, ligand, and conjugate. By employing parallel evaporative light scatter and absorbance detectors, all reactants and products are identified, and conjugate purity is maximized. We describe reversible and irreversible conversions of IRDye78 that can occur during sample purification, and describe methods for preserving conjugate stability. Using seven ligands, spanning several classes of small molecules and peptides (neutral, charged, and/or hydrophobic, we illustrate the robustness of these methods, and confirm that IRDye78 conjugates so purified retain bioactivity and permit NIR fluorescence imaging of specific targets.

Production of medical short-lived radionuclides in Canada

International Nuclear Information System (INIS)

Wiebe, L.I.

1985-01-01

The production of radionuclides for medical and biomedical research in Canada has been reviewed with respect to the national geographic and demographic characteristics which influence their use. The types of facilities available for the production of short-lived radionuclides have been summarized, and a tabulation of the radionuclides that are produced has been presented. In broad terms production facilities can be classified as belonging to one of two groups, nuclear reactor or charged-particle accelerators. The charged-particle accelerators produce the more neutron-deficient and (because of the resultant decay properties) the more useful radionuclides for medical application. The nuclear reactor facilities for radionuclide production range in size and capacity from the high-flux research reactors of AECL to the six SLOWPOKE reactors, five of which are located on university campuses across the country. The McMaster University reactor is used to produce curie quantities of fluorine-18 weekly. Millicurie amounts of a large number of radionuclides, most of which have half-lives ranging from 2 to 50 hr, are produced in the low-flux reactors, in support of basic medical research

Simulation of radionuclide transport in U.S. agriculture

International Nuclear Information System (INIS)

Sharp, R.D.; Baes, C.F. III.

1982-01-01

Because of the recent concern about the impact of energy technologies on man and related health effects, there has emerged a need for models to calculate or predict the effects of radionuclides on man. A general overview is presented of a model that calculates the ingrowth of radionuclides into man's food chain. The FORTRAN IV computer program TERRA, Transport of Environmentally Released Radionuclides in Agriculture, simulates the build-up of radionuclides in soil, four plant food compartments, in meat and milk from beef, and in the livestock food compartments that cause radionuclide build-up in milk and meat from beef. A large data set of spatially oriented parameters has been developed in conjunction with TERRA. This direct-access data set is called SITE, Specific Information on the Terrestrial Environment, and contains 35 parameters for each of 3525 half-degree longitude-latitude cells which define the lower 48 states. TERRA and SITE are used together as a package for determining radionuclide concentrations in man's food anywhere within the conterminous 48 states due to atmospheric releases

Assessment of the important radionuclides in nuclear waste

International Nuclear Information System (INIS)

Kerrisk, J.F.

1985-10-01

The relative importance of the various radionuclides contained in nuclear waste has been assessed by consideration of (1) the quantity of each radionuclide present, (2) the Environmental Protection Agency's release limits for radionuclides, (3) how retardation processes such as solubility and sorption affect radionuclie transport, and (4) the physical and chemical forms of radionuclides in the waste. Three types of waste were reviewed: spent fuel, high-level waste, and defense high-level waste. Conditions specific to the Nevada Nuclear Waste Storage Investigations project potential site at Yucca Mountain were used to describe radionuclide transport. The actinides Am, Pu, Np, and U were identified as the waste elements for which solubility and sorption data were most urgently needed. Other important waste elements were identified as Sr, Cs, C, Ni, Zr, Tc, Th, Ra, and Sn. Under some conditions, radionuclides of three elements (C, Tc, and I) may have high solubility and negligible sorption. The potential for transport of some waste elements (C and I) in the gas phase must also be evaluated for the Yucca Mountain Site. 12 refs., 17 tabs

Radionuclide Retention in Concrete Wasteforms - FY13

Energy Technology Data Exchange (ETDEWEB)

Snyder, Michelle MV; Golovich, Elizabeth C.; Wellman, Dawn M.; Crum, Jarrod V.; Lapierre, Robert; Dage, Denomy C.; Parker, Kent E.; Cordova, Elsa A.

2013-10-15

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

21 CFR 892.1390 - Radionuclide rebreathing system.

Science.gov (United States)

2010-04-01

... gaseous or volatile radionuclide or a radionuclide-labeled aerosol and permit it to be respired by the patient during nuclear medicine ventilatory tests (testing process of exchange between the lungs and the...

Naturally occurring radionuclides in agricultural products: An overview

International Nuclear Information System (INIS)

Hanlon, E.A.

1994-01-01

Low levels of naturally occurring radionuclides exist in phosphatic clays, a by-product of phosphatic mining and beneficiation processes. Concerns about these radionuclides entering the human food chain were an immediate research priority before the phosphate clays could be reclaimed for intensive agricultural purposes. Efforts included the assembly of a large body of data from both sons and plants, part of which were produced by the Polk County (Florida) Mined Lands Agricultural Research/Demonstration Project MLAR/DP. Additional detailed studies involving dairy and beef cattle (Bos taurus) were conducted by researchers working with the MLAR/DP. A national symposium was conducted in which data concerning the MLAR/DP work and other research projects also dealing with naturally occurring radionuclides in agriculture could be discussed. The symposium included invited review papers dealing with the identification of radionuclide geological origins, the geochemistry and movement of radionuclides within the environment, mechanisms of plant uptake, entry points into the food chain, and evaluation of dose and risk assessment to the consumer of low levels of radionuclides. The risk to human health of an individual obtaining 0.1 of his or her dietary intake from crops produced on phosphatic clays increased by 1 in 5 x 10 6 /yr above a control individual consuming no food grown on phosphatic clays. Leaf tissues were found to be generally higher than fruit, grain, or root tissues. The natural range in radionuclide content among various food types was greater than the difference in radionuclides content between the same food produced on phosphatic clays vs. natural soils. 19 refs

Internal radiotherapy and dosimetric study for 111In/177Lu-pegylated liposomes conjugates in tumor-bearing mice

International Nuclear Information System (INIS)

Wang, H.-E.; Yu, H.-M.; Lu, Y.-C.; Heish, N.-N.; Tseng, Yun-Long; Huang, K.-L.; Chuang, K.-T.; Chen, Chin-Hsiung; Hwang, J.-J.; Lin, W.-J.; Wang, Shyh-Jen; Ting, G.; Whang-Peng, Jacqueline; Deng, W.-P.

2006-01-01

In vivo characterization and dosimetric analysis has been performed to evaluate the potential of pegylated liposomes as carriers of radionuclides in tumor internal radiotherapy. Methods: The DTPA/PEG-liposomes were synthesized with a medium size of 110 nm, conjugated with 111 In/ 177 Lu-(oxine) 3 to afford 111 In/ 177 Lu-liposome. The stability of 111 In/ 177 Lu-liposome in serum was investigated. The biodistribution, scintigraphic imaging and pharmacokinetics of 111 In/ 177 Lu-liposomes after intravenous(i.v.) injection into C-26 tumor-bearing BALB/cByJ mice were studied. Radiation dose was estimated by MIRD-III program. Results: The incorporation efficiency of 111 In/ 177 Lu into liposomes was 95%. After incubation at 37 o C for 72 h in serum, more than 83% of radioactivity was still retained in the intact 111 In/ 177 Lu-liposomes. The biodistribution of 111 In-liposomes showed that the radioactivity in the blood decreased from 23.14±8.16%ID/g at 1 h to 0.02±0.00%ID/g at 72 h post-injection (p.i.), while reaching its maximum accumulation in tumors at 48 h p.i., with half-life in blood of 10.2 h. The results were supported by that of 177 Lu-liposomes. Scintigraphic imaging with 111 In-liposomes showed unambiguous tumor images at 48 h p.i. Dose estimation showed that the absorbed dose in tumor from 177 Lu-liposomes was 5.74x10 -5 Gy/MBq. Conclusions: This study provides an in vivo characterization and dosimetric evaluation for the use of liposome systems as carriers in targeted radionuclide therapy. The results suggest that adequate tumor targeting as well as dose delivered to tumors could be achieved by the use of radionuclide targeted liposomes

Migration of radionuclides through a river system

Energy Technology Data Exchange (ETDEWEB)

Matsunaga, Takeshi [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment

1999-03-01

Migration behavior of several atmospherically-derived radionuclides in a river watershed was studied. A main interest was in their relocation from the ground soil of the watershed to a downstream region through a river. Studied radionuclides are: {sup 137}Cs generated by weapon tests in the atmosphere; {sup 210}Pb and {sup 7}Be of naturally occurring radionuclides; {sup 137}Cs, {sup 90}Sr, {sup 239,240}Pu and {sup 241}Am released by the Chernobyl nuclear power plant accident. Dominance of the form in suspended solid in river water (particulate form) was qualified for the radionuclides in the Kuji river watershed. An importance of discharge in flooding was also confirmed. A historical budget analysis for weapon test derived {sup 137}Cs was presented for the Hi-i river watershed and its accompanied lake sediment (Lake Shinji). The work afforded a scheme of a fate of {sup 137}Cs after falling on the ground soil and on the lake surface. Several controlling factors, which can influence on the chemical form of radionuclides discharged to a river, were also investigated in the vicinity of the Chernobyl nuclear power plant. A special attention was paid on the association of the radionuclides with dissolved species in water. Preferential association of Pu and Am isotopes to a large molecular size of dissolved matrices, probably of humic substances, was suggested. (author)

Preconditioning the modified conjugate gradient method ...

African Journals Online (AJOL)

In this paper, the convergence analysis of the conventional conjugate Gradient method was reviewed. And the convergence analysis of the modified conjugate Gradient method was analysed with our extension on preconditioning the algorithm. Convergence of the algorithm is a function of the condition number of M-1A.

Mathematical simulation of sediment and radionuclide transport in estuaries

International Nuclear Information System (INIS)

Onishi, Y.; Trent, D.S.

1982-11-01

The finite element model LFESCOT (Flow, Energy, Salinity, Sediment and Contaminant Transport Model) was synthesized under this study to simulate radionuclide transport in estuaries to obtain accurate radionuclide distributions which are affected by these factors: time variance, three-dimensional flow, temperature, salinity, and sediments. Because sediment transport and radionuclide adsorption/desorption depend strongly on sizes or types of sediments, FLESCOT simulates sediment and a sediment-sorbed radionuclide for the total of three sediment-size fractions (or sediment types) of both cohesive and noncohesive sediments. It also calculates changes of estuarine bed conditions, including bed elevation changes due to sediment erosion/deposition, and three-dimensional distributions of three bed sediment sizes and sediment-sorbed radionuclides within the bed. Although the model was synthesized for radionuclide transport, it is general enough to also handle other contaminants such as heavy metals, pesticides, or toxic chemicals. The model was checked for its capability for flow, water surface elevation change, salinity, sediment and radionuclide transport under various simple conditions first, confirming the general validity of the model's computational schemes. These tests also revealed that FLESCOT can use large aspect ratios of computational cells, which are necessary in handling long estuarine study areas. After these simple tests, FLESCOT was applied to the Hudson River estuary between Chelsea and the mouth of the river to examine how well the model can predict radionuclide transport through simulating tidally influenced three-dimensional flow, salinity, sediment and radionuclide movements with their interactions

Online estimation of radionuclide transportation in water environment

International Nuclear Information System (INIS)

Yi-Jing Zhang; Li-Sheng Hu

2017-01-01

Transportation evaluation of the radionuclide waste discharged from nuclear power plants is an essential licensing issue, especially for inland sites. Basically, the dynamics of radionuclide transportation are nonlinear and time-varying. Motivated by its time-consuming computation, the work proposed an online estimation method for the radionuclide waste in water surface. After extracting the nonlinearity of factors influencing radionuclide transportation, the method utilizes transfer function and generalized autoregressive conditional heteroskedasticity models to perform deterministic and probabilistic estimations. It turns out that, the resulting predictions show high accuracy and can optimize the online discharge management of radioactive waste for nuclear power plants. (author)

Radionuclide examinations

International Nuclear Information System (INIS)

Lentle, B.C.

1989-01-01

This paper reports on radionuclide examinations of the pancreas. The pancreas, situated retroperitonally high in the epigastrium, was a particularly difficult organ to image noninvasively before ultrasonography and computed tomography (CT) became available. Indeed the organ still remains difficult to examine in some patients, a fact reflected in the variety of methods available to evaluate pancreatic morphology. It is something of a paradox that the pancreas is metabolically active and physiologically important but that its examination by radionuclide methods has virtually ceased to have any role in day-to-day clinical practice. To some extent this is caused by the tendency of the pancreas's commonest gross diseases emdash carcinoma and pancreatitis, for example emdash to result in nonfunction of the entire organ. Disorders of pancreatic endocrine function have generally not required imaging methods for diagnosis, although an understanding of diabetes mellitus and its nosology has been advanced by radioimmunoassay of plasma insulin concentrations

Radionuclides in terrestrial ecosystems

International Nuclear Information System (INIS)

Howard, B.J.; Kennedy, V.H.; Nelson, A.

1983-06-01

A bibliographical database has been developed to provide quick access to research and background literature in the field of radioecology. This is a development of an earlier database described by Nelson (Bocock 1981). ITE's particular fields of interest have led to a subject bias in the bibliography towards studies in Cumbria, especially those concerned with radionuclides originating from the reprocessing plant at Sellafield, and towards ecological research studies that are complementary to radionuclide studies. Other subjects covered, include the chemistry of radionuclides, budgets and transfers within ecosystems and techniques for the analysis of environmental samples. ITE's research objectives have led to the establishment of a specialized database which is intended to complement rather than compete with the large international databases made available by suppliers such as IRS-DIALTECH or DIALOG. Currently the database holds about 1900 references which are stored on a 2 1/2 megabyte hard disk on a Digital PDP11/34 computer operating under a time shared system. The references follow a standard format. (author)

Status report on radionuclide transfer

International Nuclear Information System (INIS)

1980-01-01

At the suggestion of the Federal Minstry of the Interior, in June 1978, a group of scientists from several institutions who are active in the field of radionuclide transfer or are interested in these problems got together. During the discussions of the work team, especially the transfer soil/plants was emphasized. Then the work team set up a status report on the transfer of the radionuclides relevant in the sense of the radiation protection act. The nuclides H 3 and C14, the isotopes of the Sr, J, and Cs, Tc99, the so-called corrosion nuclides Mn54, Fe59, co-isotopes and Zn65, and isotopes of Pu, Am, and Cm were regarded as important for a possible radiation exposition. Recent investigations revealed that also the natural radionuclides Ra226, Po210, and Pb210 should be covered by the investigations. The goal of this status report is to present the level of knowledge on the transfer of these radionuclides to man in a brief form, giving hints at the most important literature. It was requested by the Federal Ministry of the Interior, as fas as possible, to indicate transfer factors which are necessary for the radio-occology act to be decreed according to Para. 45 of the radiation protection act. Another goal of the report was to show the gap in the knowledge on the radio nuclide transfer. This was thought to help to create a basis for the decisions of the Federal Ministry concerning the support of other investigation projects in the field of transfer of radionuclides. (orig./MG) [de

The fate and importance of radionuclides produced in nuclear events

Energy Technology Data Exchange (ETDEWEB)

Shore, B; Anspaugh, L; Chertok, R; Gofman, J; Harrison, F; Heft, R; Koranda, J; Ng, Y; Phelps, P; Potter, G; Tamplin, A [Lawrence Radiation Laboratory, University of California, Livermore, CA (United States)

1969-07-01

Some of the major program at the Bio-Medical Division concerned with the fate and importance of the fission products, the radionuclides induced in the device materials, the radionuclides induced in the environment surrounding the device, and the tritium produced in Plowshare cratering events will be discussed. These programs include (1) critical unknowns in predicting organ and body burdens from radionuclides produced in cratering events; (2) the analysis with a high-resolution solid state gamma ray spectrometer of radionuclides in complex biological and environmental samples; (3) the characterization of radioactive particles from cratering detonation; (4) the biological availability to beagles, pigs and goats of radionuclides in Plowshare debris; (5) the biological availability to aquatic animals of radionuclides in Plowshare and other nuclear debris and the biological turnover of critical nuclides in specific aquatic animals; (6) the biological availability of Plowshare and other nuclear debris radionuclides to dairy cows and the transplacental transport of debris radionuclides in the dairy cow; (7) the persistence and behavior of radionuclides, particularly tritium, at sites of Plowshare and other nuclear detonations; and (8) somatic effects of Low Dose Radiation: Chromosome studies. (author)

The fate and importance of radionuclides produced in nuclear events

International Nuclear Information System (INIS)

Shore, B.; Anspaugh, L.; Chertok, R.; Gofman, J.; Harrison, F.; Heft, R.; Koranda, J.; Ng, Y.; Phelps, P.; Potter, G.; Tamplin, A.

1969-01-01

Some of the major program at the Bio-Medical Division concerned with the fate and importance of the fission products, the radionuclides induced in the device materials, the radionuclides induced in the environment surrounding the device, and the tritium produced in Plowshare cratering events will be discussed. These programs include (1) critical unknowns in predicting organ and body burdens from radionuclides produced in cratering events; (2) the analysis with a high-resolution solid state gamma ray spectrometer of radionuclides in complex biological and environmental samples; (3) the characterization of radioactive particles from cratering detonation; (4) the biological availability to beagles, pigs and goats of radionuclides in Plowshare debris; (5) the biological availability to aquatic animals of radionuclides in Plowshare and other nuclear debris and the biological turnover of critical nuclides in specific aquatic animals; (6) the biological availability of Plowshare and other nuclear debris radionuclides to dairy cows and the transplacental transport of debris radionuclides in the dairy cow; (7) the persistence and behavior of radionuclides, particularly tritium, at sites of Plowshare and other nuclear detonations; and (8) somatic effects of Low Dose Radiation: Chromosome studies. (author)

99mTC-dextran-antibody conjugates. Labelling procedures

International Nuclear Information System (INIS)

Marquez, M.; Westlin, J.E.; Nilsson, S.; Holmberg, A.R.

1996-01-01

Dextran forms stable chelates with 99m Tc, a radionuclide with ideal properties for planar scintigraphic and tomographic imaging. This study investigates some of the factors of importance to the formation of 99m Tc-dextran. The complex was used for the technetium labelling of a monoclonal antibody. Two radiolabelling methods were studied: Direct dextran labelling with the reductant dissolved in HCl and labelling via a weak 'transfer' chelator (tartaric acid) with the reductant dissolved in ethanol. Different conditions during the labelling reaction were studied. Finally, dextran was coupled to a monoclonal anticytokeratin antibody and the conjugate was subsequently radiolabelled with 99m Tc. Gel filtration (GFR) and thin layer chromatography (TLC) were compared as methods for estimation of the labelling efficiency. When using 10-500 μM of ligand, 5-100 μM SnC1 2 with 10-500 MBq of technetium at pH7 incubated for 10-15 min, the radiolabelling seemed optimal (70-75% labelling efficiency). It was found that 100 μM tartaric acid used as a weak intermediate chelator with SnCl 2 dissolved in ethanol improved the reproducibility of the labelling. The labelling efficiency was not affected by either the presence of oxygen or the addition of an oxygen scavenger during the labelling incubation. In general, TLC showed higher labelling efficiencies than GFR, indicating inadequate separation of the different moieties. (orig.)

Migration of radionuclides in geologic media: Fundamental research needs

International Nuclear Information System (INIS)

Reed, D.T.; Zachara, J.M.; Wildung, R.E.; Wobber, F.J.

1990-01-01

An assessment of the fundamental research needs in understanding and predicting the migration of radionuclides in the subsurface is provided. Emphasis is on the following three technical areas: (1) aqueous speciation of radionuclides, (2) the interaction of radionuclides with substrates, and (3) intermediate-scale interaction studies. This research relates to important issues associated with environmental restoration and remediation of DOE sites contaminated with mixed radionuclide-organic wastes. 64 refs., 1 fig., 1 tab

Radiopharmaceuticals and other compounds labelled with short-lived radionuclides

CERN Document Server

Welch, Michael J

2013-01-01

Radiopharmaceuticals and Other Compounds Labelled with Short-Lived Radionuclides covers through both review and contributed articles the potential applications and developments in labeling with short-lived radionuclides whose use is restricted to institutions with accelerators. The book discusses the current and potential use of generator-produced radionuclides as well as other short-lived radionuclides, and the problems of quality control of such labeled compounds. The book is useful to nuclear medicine physicians.

Radionuclides incorporation in activated natural nanotubes

International Nuclear Information System (INIS)

Silva, Jose Parra

2016-01-01

Natural palygorskite nanotubes show suitable physical and chemical properties and characteristics to be use as potential nanosorbent and immobilization matrix for the concentration and solidification of radionuclides present in nuclear wastes. In the development process of materials with sorption properties for the incorporation and subsequent immobilization of radionuclides, the most important steps are related with the generation of active sites simultaneously to the increase of the specific surface area and suitable heat treatment to producing the structural folding. This study evaluated the determining parameters and conditions for the activation process of the natural palygorskite nanotubes aiming at the sorption of radionuclides in the nanotubes structure and subsequent evaluation of the parameters involve in the structural folding by heat treatments. The optimized results about the maximum sorption capacity of nickel in activated natural nanotubes show that these structures are apt and suitable for incorporation of radionuclides similar to nickel. By this study is verified that the optimization of the acid activation process is fundamental to improve the sorption capacities for specifics radionuclides by activated natural nanotubes. Acid activation condition optimized maintaining structural integrity was able to remove around 33.3 wt.% of magnesium cations, equivalent to 6.30·10 -4 g·mol -1 , increasing in 42.8% the specific surface area and incorporating the same molar concentration of nickel present in the liquid radioactive waste at 80 min. (author)

100 Years of radionuclide metrology

International Nuclear Information System (INIS)

Judge, S.M.; Arnold, D.; Chauvenet, B.; Collé, R.; De Felice, P.; García-Toraño, E.; Wätjen, U.

2014-01-01

The discipline of radionuclide metrology at national standards institutes started in 1913 with the certification by Curie, Rutherford and Meyer of the first primary standards of radium. In early years, radium was a valuable commodity and the aim of the standards was largely to facilitate trade. The focus later changed to providing standards for the new wide range of radionuclides, so that radioactivity could be used for healthcare and industrial applications while minimising the risk to patients, workers and the environment. National measurement institutes responded to the changing demands by developing new techniques for realising primary standards of radioactivity. Looking ahead, there are likely to be demands for standards for new radionuclides used in nuclear medicine, an expansion of the scope of the field into quantitative imaging to facilitate accurate patient dosimetry for nuclear medicine, and an increasing need for accurate standards for radioactive waste management and nuclear forensics. - Highlights: • The driving forces for the development of radionuclide metrology. • Radium standards to facilitate trade of this valuable commodity in the early years. • After 1950, focus changes to healthcare and industrial applications. • National Measurement Institutes develop new techniques, standards, and disseminate the best practice in measurement. • Challenges in nuclear medicine, radioactive waste management and nuclear forensics

Underground radionuclide migration at the Nevada Test Site

International Nuclear Information System (INIS)

Nimz, G.J.; Thompson, J.L.

1992-01-01

This document reviews results from a number of studies concerning underground migration of radionuclides from nuclear test cavities at the Nevada Test Site (NTS). Discussed are all cases known to the Department of Energy's Hydrology and Radionuclide Migration Program where radionuclides have been detected outside of the immediate vicinity of nuclear test cavities that are identifiable as the-source of the nuclides, as well as cases where radionuclides might have been expected and were intentionally sought but not fixed. There are nine locations where source-identifiable radionuclide migration has been detected, one where migration was purposely induced by pumping, and three where migration might be expected but was not found. In five of the nine cases of non-induced migration, the inferred migration mechanism is prompt fracture injection during detonation. In the other four cases, the inferred migration mechanism is water movement. In only a few of the reviewed cases can the actual migration mechanism be stated with confidence, and the attempt has been made to indicate the level of confidence for each case. References are cited where more information may be obtained. As an aid to future study, this document concludes with a brief discussion of the aspects of radionuclide migration that, as the present review indicates, are not yet understood. A course of action is suggested that would produce a better understanding of the phenomenon of radionuclide migration

Inter-comparison of dynamic models for radionuclide transfer to marine biota in a Fukushima accident scenario

Energy Technology Data Exchange (ETDEWEB)

Vives i Batlle, J.; Beresford, N. A.; Beaugelin-Seiller, K.; Bezhenar, R.; Brown, J.; Cheng, J. -J.; Ćujić, M.; Dragović, S.; Duffa, C.; Fiévet, B.; Hosseini, A.; Jung, K. T.; Kamboj, S.; Keum, D. -K.; Kryshev, A.; LePoire, D.; Maderich, V.; Min, B. -I.; Periáñez, R.; Sazykina, T.; Suh, K. -S.; Yu, C.; Wang, C.; Heling, R.

2016-03-01

We report an inter-comparison of eight models designed to predict the radiological exposure of radionuclides in marine biota. The models were required to simulate dynamically the uptake and turnover of radionuclides by marine organisms. Model predictions of radionuclide uptake and turnover using kinetic calculations based on biological half-life (TB1/2) and/or more complex metabolic modelling approaches were used to predict activity concentrations and, consequently, dose rates of 90Sr, 131I and 137Cs to fish, crustaceans, macroalgae and molluscs under circumstances where the water concentrations are changing with time. For comparison, the ERICA Tool, a model commonly used in environmental assessment, and which uses equilibrium concentration ratios, was also used. As input to the models we used hydrodynamic forecasts of water and sediment activity concentrations using a simulated scenario reflecting the Fukushima accident releases. Although model variability is important, the intercomparison gives logical results, in that the dynamic models predict consistently a pattern of delayed rise of activity concentration in biota and slow decline instead of the instantaneous equilibrium with the activity concentration in seawater predicted by the ERICA Tool. The differences between ERICA and the dynamic models increase the shorter the TB1/2 becomes; however, there is significant variability between models, underpinned by parameter and methodological differences between them. The need to validate the dynamic models used in this intercomparison has been highlighted, particularly in regards to optimisation of the model biokinetic parameters.

Doxorubicin conjugated to D-alpha-tocopheryl polyethylene glycol 1000 succinate (TPGS): conjugation chemistry, characterization, in vitro and in vivo evaluation.

Science.gov (United States)

Cao, Na; Feng, Si-Shen

2008-10-01

To develop a polymer-anticancer drug conjugate, D-alpha-tocopheryl polyethylene glycol 1000 succinate (TPGS) was employed as a carrier of doxorubicin (DOX) to enhance its therapeutic effects and reduce its side effects. Doxorubicin was chemically conjugated to TPGS. The molecular structure, drug loading efficiency, drug release kinetics and stability of the conjugate were characterized. The cellular uptake, intracellular distribution, and cytotoxicity were accessed by using MCF-7 breast cancer cells and C6 glioma cells as in vitro cell model. The conjugate showed higher cellular uptake efficiency and broader distribution within the cells. Judged by IC(50), the conjugate was found 31.8, 69.6, 84.1% more effective with MCF-7 cells and 43.9, 87.7, 42.2% more effective with C6 cells than the parent drug after 24, 48, 72 h culture, respectively. The in vivo pharmacokinetics and biodistribution were investigated after an i.v. administration at 5 mg DOX/kg body weight in rats. Promisingly, 4.5-fold increase in the half-life and 24-fold increase in the area-under-the-curve (AUC) of DOX were achieved for the TPGS-DOX conjugate compared with the free DOX. The drug level in heart, gastric and intestine was significantly reduced, which is an indication of reduced side effects. Our TPGS-DOX conjugate showed great potential to be a prodrug of higher therapeutic effects and fewer side effects than DOX itself.

21 CFR 892.5700 - Remote controlled radionuclide applicator system.

Science.gov (United States)

2010-04-01

... radionuclide applicator system. (a) Identification. A remote controlled radionuclide applicator system is an... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Remote controlled radionuclide applicator system... include patient and equipment supports, component parts, treatment planning computer programs, and...

The contamination of the oceans by anthropogenic radionuclides

International Nuclear Information System (INIS)

Figueira, Rubens C.L.; Cunha, Ieda I.L.

1998-01-01

Several hundreds of artificial of artificial radionuclides are produced as the result of human activities, such as the applications of nuclear reactors and particle accelerators, testing of nuclear weapons and nuclear accidents. Many of these radionuclides are short-lived and decay quickly after their production, but some of them are longer-lived and are released into the environment. From the radiological point of view the most important radionuclides are cesium-137, strontium-90 and plutonium-239, due to their chemical and nuclear characteristics. The two first radioisotopes present long half life (30 and 28 years), high fission yields and chemical behaviour similar to potassium and calcium, respectively. No stable element exists for plutonium-239, that presents high radiotoxity, longh half-life (24000 years) and some marine organisms accumulate plutonium at high levels. The radionuclides introduced into marine environment undergo various physical, chemical and biological processes taking place in the sea. These processes may be due to physical, dispersion or complicated chemical and biological interactions of the radionuclides with inorganic and organic suspend matter, variety of living organism, bottom sediments, etc. The behaviour of radionuclides in the sea depends primarily on their chemical properties, but it may also be influenced by properties of interacting matrices and other environmental factors. The major route of radiation exposure of man to artificial radionuclides occuring in the marine environment is through ingestion of radiologically contamined marine organisms. This paper summarizes the main sources of contamination in the marine environment and presents an overview covering the oceanic distribution of anthropogenic radionuclides in the FAO regions. A great number of measurements of artificial radioclides have been carried out on various marine environmental samples in different oceans over the world, being cesium-137 the most widely measured

Radionuclide examination in rheumatology

International Nuclear Information System (INIS)

Streda, A.; Kolar, J.; Valesova, M.

1984-01-01

On the basis of twenty years of experience with the use of radionuclides in bone and articular rheumatic diseases indications for such examinations are summed up. The main advantage of the use of radionuclide methods is that they bring forward early diagnosis of tissue reconstruction which can thus be detected at the stage of microstructural changes. They also provide earlier and more reliable detection of the degree of the pathological process than is provided by X-ray examination. In some cases scintiscan may also be found useful as a method for following up the results of treatment of rheumatic diseases. (author)

Solubility limited radionuclide transport through geologic media

International Nuclear Information System (INIS)

Muraoka, Susumu; Iwamoto, Fumio; Pigford, T.H.

1980-11-01

Prior analyses for the migration of radionuclides neglect solubility limits of resolved radionuclide in geologic media. But actually some of the actinides may appear in chemical forms of very low solubility. In the present report we have proposed the migration model with no decay parents in which concentration of radionuclide is limited in concentration of solubility in ground water. In addition, the analytical solutions of the space-time-dependent concentration are presented in the case of step release, band release and exponential release. (author)

Radionuclide determination of right and left ventricular stroke volumes

Energy Technology Data Exchange (ETDEWEB)

Shen, Wei Feng; Roubin, G S; Choong, C Y.P.; Harris, P J; Flether, P J; Kelly, D T; Uren, R F; Hutton, B F

1985-03-01

The relationship between radionuclide and thermodilution measurement of stroke volumes (SV) was investigated in 30 patients without valvular regurgitation or intracardiac shunt (group A) at rest and during exercise. Both attenuated radionuclide right ventricular (RV) and left ventricular (LV) SV measurements correlated well with the SV determined by the thermodilution method (r = 0.87 and r = 0.93, all P < 0.001). The reliability of the radionuclide method to estimate SV was evaluated prospectively in two additional groups of patients. In 11 patients without valvular regurgitation or intracardiac shunt (group B) the radionuclide RVSV and LVSV closely approximated to thermodilution SV at rest and during exercise. In 15 patients with aortic regurgitation (group C) the radionuclide stroke volume ratio correlated well with the angiographic regurgitant fraction. Thus, both RVSV and LVSV and the severity of aortic regurgitation can be reliably measured with gated radionuclide ventriculography.

Methods for determining radionuclide retardation factors: status report

International Nuclear Information System (INIS)

Relyea, J.F.; Serne, R.J.; Rai, D.

1980-04-01

This report identifies a number of mechanisms that retard radionuclide migration, and describes the static and dynamic methods that are used to study such retardation phenomena. Both static and dynamic methods are needed for reliable safety assessments of underground nuclear-waste repositories. This report also evaluates the extent to which the two methods may be used to diagnose radionuclide migration through various types of geologic media, among them unconsolidated, crushed, intact, and fractured rocks. Adsorption is one mechanism that can control radionuclide concentrations in solution and therefore impede radionuclide migration. Other mechanisms that control a solution's radionuclide concentration and radionuclide migration are precipitation of hydroxides and oxides, oxidation-reduction reactions, and the formation of minerals that might include the radionuclide as a structural element. The retardation mechanisms mentioned above are controlled by such factors as surface area, cation exchange capacity, solution pH, chemical composition of the rock and of the solution, oxidation-reduction potential, and radionuclide concentration. Rocks and ground waters used in determining retardation factors should represent the expected equilibrium conditions in the geologic system under investigation. Static test methods can be used to rapidly screen the effects of the factors mentioned above. Dynamic (or column) testing, is needed to assess the effects of hydrodynamics and the interaction of hydrodynamics with the other important parameters. This paper proposes both a standard method for conducting batch Kd determinations, and a standard format for organizing and reporting data. Dynamic testing methods are not presently developed to the point that a standard methodology can be proposed. Normal procedures are outlined for column experimentation and the data that are needed to analyze a column experiment are identified

Bis-polymer lipid-peptide conjugates and nanoparticles thereof

Energy Technology Data Exchange (ETDEWEB)

Xu, Ting; Dong, He; Shu, Jessica; Dube, Nikhil

2018-04-24

The present invention provides bis-polymer lipid-peptide conjugates containing a hydrophobic block and headgroup containing a helical peptide and two polymer blocks. The conjugates can self-assemble to form helix bundle subunits, which in turn assemble to provide micellar nanocarriers for drug cargos and other agents. Particles containing the conjugates and methods for forming the particles are also disclosed.

Research progess on treatment of cancer with targeted radionuclide therapy

International Nuclear Information System (INIS)

Luo Jiawen; Zhang Caixia

2008-01-01

The new development and situation of targeted radionuclide therapy in oncology is described, which include radioimmunotherapy, peptide receptor radionuclide therapy, gene therapy and radionuclide labled chemotherapeutics therapy. The application research on labled carrier of those therapy is emphasized. Meanwhile, the research progess of indomethacin and its combined with targeted radionuclide therapy is also described. (authors)

Fire fighting in a radionuclide laboratory

International Nuclear Information System (INIS)

Wenzel, H.

1991-01-01

A fire-brigade was called to a laboratory which held a handling licence for the radionuclides C-14, T, P-32, Se-75, Mo-99, and S-35. The fire-brigade was unaware of a release of radionuclides. Therefore they used respiratory equipment, and all persons present were subsequently examined for contamination. (DG) [de

Permissible annual depositions and radionuclide concentrations in air

International Nuclear Information System (INIS)

Belyaev, V.A.; Golovko, M.Yu.

1993-01-01

It is established that it necessary to take into account the other ways of radionuclide intake apart from the inhalation one when determining the standards for radionuclide contamination of the atmospheric air. Whereby it is proposed to standardize annual depositions rather than permissible concentration in the atmospheric air for the ways related to radionuclide releases on the ground surface, which is explained by ambiguity of their dry deposition rate from the air. Formulae and results of calculation of standard characteristics are presented. The permissible radionuclide depositions, related to the intake through food chains are calculated with account for diet diversity, agroclimatic and phenological parameters in different regions of the country

Understanding Radionuclide Interactions with Layered Materials

Science.gov (United States)

Wang, Y.

2015-12-01

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

Radionuclide transport in a single fissure

International Nuclear Information System (INIS)

Eriksen, T.E.

1988-12-01

The study of radionuclide migration through rock is currently of great interest due to its relevance to the possible escape paths into the biosphere of radionuclides released from high level radioactive wastes burried in deep geological repositories. While water will provide the vehicle for transportation, interaction with geological material may greatly influence the radionuclide movement relative that of water. A flow system for laboratory studies of radionuclide transport in natural fissures in granitic rock under reducing conditions is described. The system based on the use of synthetic ground water equilibrated with granitic rock in a well sealed system, allow experiments to be carried out at -240 mV reduction potential. In flow experiments with technetium the retardation was found to be dependent on the method used for reducing TcO 4 - . The preparation of the tracer solutions is crucial, as some of the redox-reactions may be very slow. The dynamics of the Tc(VII) reduction and also speciation need to be carried out in separate experiments. (4 illustrations, 5 tables)

Radionuclide therapy practice and facilities in Europe

International Nuclear Information System (INIS)

Hoefnagel, C.A.; Clarke, S.E.M.; Fischer, M.; Chatal, J.F.; Lewington, V.J.; Nilsson, S.; Troncone, L.; Vieira, M.R.

1999-01-01

Using a questionnaire the EANM Task Group Radionuclide Therapy in 1993 collected data on the current practice of radionuclide therapy in European countries. Subsequently, at the request of the EANM Executive Committee, the EANM Radionuclide Therapy Committee has made an inventory of the distribution of facilities for radionuclide therapy and undertaken an assessment of the total number of patients treated throughout Europe and of the types of treatment provides, with the aim of supporting the development of policy to adjust the available capacity to the needs by the year 2000. For this purpose, a second, more detailed questionnaire was sent out the members and national advisors of the Committee (see below), who gathered the data for each country that was a member of the EANM at the time. It is concluded that a wide bariation in therapy practice exists across Europe, particularly in the utilisation of radionuclide therapy, the requirement and availability of proper isolation facilities and the background training of those undertaking therapy. More uniform guidelines and legislation are required, although changes in legislation may have a significant impact in some countries. Although there is wide variation in the therapies used in each country, one the whole it appears that there is an underutilisation of nuclear medicine as a therapeutic modality. A rapidly increasing role may be expected, in particular for oncological indications requiring high-dose radionuclide treatment. Therefore there is an urgent need for a greater number of isolation beds in dedicated centers throughout Europe

Conjugated polymer nanoparticles, methods of using, and methods of making

KAUST Repository

Habuchi, Satoshi; Piwonski, Hubert Marek; Michinobu, Tsuyoshi

2017-01-01

Embodiments of the present disclosure provide for conjugated polymer nanoparticle, method of making conjugated polymer nanoparticles, method of using conjugated polymer nanoparticle, polymers, and the like.

Conjugated polymer nanoparticles, methods of using, and methods of making

KAUST Repository

Habuchi, Satoshi

2017-03-16

Embodiments of the present disclosure provide for conjugated polymer nanoparticle, method of making conjugated polymer nanoparticles, method of using conjugated polymer nanoparticle, polymers, and the like.

Surface diffusion of sorbed radionuclides

International Nuclear Information System (INIS)

Berry, J.A.; Bond, K.A.

1991-01-01

Surface diffusion has in the past been invoked to explain rates of radionuclide migration which were greater than those predicted. Results were generally open to interpretation but the possible existence of surface diffusion, whereby sorbed radionuclides could potentially migrate at much enhanced rates, necessitated investigation. In this work through-diffusion experiments have shown that although surface diffusion does exist for some nuclides, the magnitude of the phenomenon is not sufficient to affect repository safety assessment modelling. (author)

DNA damage induced by radionuclide internal irradiation

International Nuclear Information System (INIS)

Cui Fengmei; Zhao Jingyong; Hong Chengjiao; Lao Qinhua; Wang Liuyi; Yang Shuqin

2004-01-01

Objective: To study the DNA damage of peripheral blood mononuclear cell (PBMC) in rats exposed to radionuclide internal irradiation. Methods: The radionuclides were injected into the rats and single cell get electrophoresis (SCGE) was performed to detect the length of DNA migration in the rat PBMC. Results: DNA migration in the rat PBMC increased with accumulative dose or dose-rate. It showed good relationship of dose vs. response and of dose-rate vs. response, both relationship could be described as linear models. Conclusion: Radionuclide internal irradiation could cause DNA damage in rat PBMC. (authors)

Radionuclide Basics: Iodine

Science.gov (United States)

... Centers Radiation Protection Contact Us Share Radionuclide Basics: Iodine Iodine (chemical symbol I) is a chemical element. ... in the environment Iodine sources Iodine and health Iodine in the Environment All 37 isotopes of iodine ...

40 CFR 141.66 - Maximum contaminant levels for radionuclides.

Science.gov (United States)

2010-07-01

... beta particle and photon radioactivity from man-made radionuclides in drinking water must not produce.../year). (2) Except for the radionuclides listed in table A, the concentration of man-made radionuclides... may make this technology too complex for small surface water systems. e Removal efficiencies can vary...

Nonlinear conjugate gradient methods in micromagnetics

Directory of Open Access Journals (Sweden)

J. Fischbacher

2017-04-01

Full Text Available Conjugate gradient methods for energy minimization in micromagnetics are compared. The comparison of analytic results with numerical simulation shows that standard conjugate gradient method may fail to produce correct results. A method that restricts the step length in the line search is introduced, in order to avoid this problem. When the step length in the line search is controlled, conjugate gradient techniques are a fast and reliable way to compute the hysteresis properties of permanent magnets. The method is applied to investigate demagnetizing effects in NdFe12 based permanent magnets. The reduction of the coercive field by demagnetizing effects is μ0ΔH = 1.4 T at 450 K.

Human glutathione S-transferase-mediated glutathione conjugation of curcumin and efflux of these conjugates in Caco-2 cells

NARCIS (Netherlands)

Usta, M.; Wortelboer, H.M.; Vervoort, J.J.M.; Boersma, M.G.; Rietjens, I.M.C.M.; Bladeren, van P.J.; Cnubben, N.H.P.

2007-01-01

Curcumin, an alpha,beta-unsaturated carbonyl compound, reacts with glutathione, leading to the formation of two monoglutathionyl curcumin conjugates. In the present study, the structures of both glutathione conjugates of curcumin were identified by LC-MS and one- and two-dimensional H-1 NMR

Selective Covalent Conjugation of Phosphorothioate DNA Oligonucleotides with Streptavidin

Directory of Open Access Journals (Sweden)

Christof M. Niemeyer

2011-08-01

Full Text Available Protein-DNA conjugates have found numerous applications in the field of diagnostics and nanobiotechnology, however, their intrinsic susceptibility to DNA degradation by nucleases represents a major obstacle for many applications. We here report the selective covalent conjugation of the protein streptavidin (STV with phosphorothioate oligonucleotides (psDNA containing a terminal alkylthiolgroup as the chemically addressable linking unit, using a heterobifunctional NHS-/maleimide crosslinker. The psDNA-STV conjugates were synthesized in about 10% isolated yields. We demonstrate that the terminal alkylthiol group selectively reacts with the maleimide while the backbone sulfur atoms are not engaged in chemical conjugation. The novel psDNA-STV conjugates retain their binding capabilities for both biotinylated macromolecules and the complementary nucleic acid. Moreover, the psDNA-STV conjugate retained its binding capacity for complementary oligomers even after a nuclease digestion step, which effectively degrades deoxyribonucleotide oligomers and thus the binding capability of regular DNA-STV conjugates. The psDNA-STV therefore hold particular promise for applications e.g. in proteome research and novel biosensing devices, where interfering endogenous nucleic acids need to be removed from analytes by nuclease digestion.

Dye linked conjugated homopolymers: using conjugated polymer electroluminescence to optically pump porphyrin-dye emission

DEFF Research Database (Denmark)

Nielsen, K.T.; Spanggaard, H.; Krebs, Frederik C

2004-01-01

. Electroluminescent devices of the homopolymer itself and of the zinc-porphyrin containing polymer were prepared and the nature of the electroluminescence was characterized. The homopolymer segments were found to optically pump the emission of the zinc-porphyrin dye moities. The homopolymer exhibits blue......Zinc-porphyrin dye molecules were incorporated into the backbone of a conjugated polymer material by a method, which allowed for the incorporation of only one zinc-porphyrin dye molecule into the backbone of each conjugated polymer molecule. The electronic properties of the homopolymer were...

Lipid-peptide-polymer conjugates and nanoparticles thereof

Science.gov (United States)

Xu, Ting; Dong, He; Shu, Jessica

2015-06-02

The present invention provides a conjugate having a peptide with from about 10 to about 100 amino acids, wherein the peptide adopts a helical structure. The conjugate also includes a first polymer covalently linked to the peptide, and a hydrophobic moiety covalently linked to the N-terminus of the peptide, wherein the hydrophobic moiety comprises a second polymer or a lipid moiety. The present invention also provides helix bundles form by self-assembling the conjugates, and particles formed by self-assembling the helix bundles. Methods of preparing the helix bundles and particles are also provided.

Novel β-cyclodextrin-eosin conjugates.

Science.gov (United States)

Benkovics, Gábor; Afonso, Damien; Darcsi, András; Béni, Szabolcs; Conoci, Sabrina; Fenyvesi, Éva; Szente, Lajos; Malanga, Milo; Sortino, Salvatore

2017-01-01

Eosin B (EoB) and eosin Y (EoY), two xanthene dye derivatives with photosensitizing ability were prepared in high purity through an improved synthetic route. The dyes were grafted to a 6-monoamino-β-cyclodextrin scaffold under mild reaction conditions through a stable amide linkage using the coupling agent 4-(4,6-dimethoxy-1,3,5-triazin-2-yl)-4-methylmorpholinium chloride. The molecular conjugates, well soluble in aqueous medium, were extensively characterized by 1D and 2D NMR spectroscopy and mass spectrometry. Preliminary spectroscopic investigations showed that the β-cyclodextrin-EoY conjugate retains both the fluorescence properties and the capability to photogenerate singlet oxygen of the unbound chromophore. In contrast, the corresponding β-cyclodextrin-EoB conjugate did not show either relevant emission or photosensitizing activity probably due to aggregation in aqueous medium, which precludes any response to light excitation.

Novel β-cyclodextrin–eosin conjugates

Directory of Open Access Journals (Sweden)

Gábor Benkovics

2017-03-01

Full Text Available Eosin B (EoB and eosin Y (EoY, two xanthene dye derivatives with photosensitizing ability were prepared in high purity through an improved synthetic route. The dyes were grafted to a 6-monoamino-β-cyclodextrin scaffold under mild reaction conditions through a stable amide linkage using the coupling agent 4-(4,6-dimethoxy-1,3,5-triazin-2-yl-4-methylmorpholinium chloride. The molecular conjugates, well soluble in aqueous medium, were extensively characterized by 1D and 2D NMR spectroscopy and mass spectrometry. Preliminary spectroscopic investigations showed that the β-cyclodextrin–EoY conjugate retains both the fluorescence properties and the capability to photogenerate singlet oxygen of the unbound chromophore. In contrast, the corresponding β-cyclodextrin–EoB conjugate did not show either relevant emission or photosensitizing activity probably due to aggregation in aqueous medium, which precludes any response to light excitation.

Choice of radionuclide for antibody labelling: new perspectives

International Nuclear Information System (INIS)

Hazra, D.K.; Dass, S.

1983-01-01

The expanding horizons of labelled antibody techniques in diagnostic imaging or assay, therapy and research and the availabilities of monoclonal antibodies is resulting in a demand for suitable radionuclides as antibody labels. An outline is given of the different criteria for choosing an appropriate radionuclide for labelling an antibody depending on its particular field of use. The requirements of procedures for firmly linking radionuclides to antibodies are also given. (U.K.)

Emissions of the corrosion radionuclides in an atmosphere

International Nuclear Information System (INIS)

Vardanyan, M.

2010-01-01

In area of Armenian nuclear power plant location, in atmospheric air in majority of cases log two technogenic radionuclides: l 37 C s and 9 0 S r. Presence of these radionuclides basically is caused by global fall out (consequences of tests of the nuclear weapon and Chernobyl NPP accident), whose contribution to the contents of these radionuclides in atmosphere is incomparably greater, than emissions from the NPP. However there are some cases when in an atmosphere are registered the technogenic radionuclides, caused by emissions from NPP. In the present work such case is considered. Gas-aerosol releases of NPP in the atmosphere are carefully purified by means of various high-efficiency filters and gas-cleaning systems. Nevertheless, one should forecast and measure, the possible impact of these releases on the environment in the regions surrounding the NPP. Radioactive releases of the Armenian NPP (ANPP) contain the set of radionuclides characteristic for NPPs of this type. They may be divided into three groups: 1 31 I , 1 37 C s, 1 34 C s, 9 0 S r and 8 9 S r fission fragments, isotopes of noble gases krypton and xenon and other radionuclides; corrosion originated radionuclides: 6 0 C o, 1 10m A g, 5 4 M n, 5 l C r and others; activation products of the heat-transfer agent itself. It should be noted that the amount of radioactive materials released in the environment by the ANPP during the whole period of its operation was much lower than the admissible quantities specified in the corresponding legal documents (RSN, NPPSP) acting in Armenia, which are practically identical to the internationally accepted norms. The amounts of releases and their radionuclides composition for the ANPP are given

Radiopharmaceutical labeling research

International Nuclear Information System (INIS)

Anon.

1985-01-01

The objective of this research is to develop methods of attaching radionuclides to monoclonal antibodies and antibody fragments for use in tumor imaging and internal radiation therapy. Monoclonal antibodies and their fragments are of interest because they enable the selective targeting of tumors. The labeled antibodies could be employed as carriers to transport radioisotopes to tumors, thus minimizing total-body radiation dose and radiation damage to normal tissue. Because the time required for labeled antibodies to find the tumor antigen and deliver the dose to the tumor is estimated to be about 1-3 days, radionuclides with a l- to 3-day half-life would be optimum for this purpose. Two of the radionuclides produced at LAMPF, 67 Cu and 77 Br, have the suitable half-life and nuclear-decay properties for use in tumor imaging or therapy with radiolabeled antibodies. These radionuclides and the efforts to prepare radiolabeled antibodies with them are described. We have used three different approaches to meet this objective of labeling antibodies: (1) labeling chelating agents with metal radionuclides, then conjugating the labeled chelating agents to antibodies; (2) conjugating activated chelating agents to antibodies, followed by metalation with metal radionuclides; and (3) radiobrominating small molecules that can be conjugated to antibodies

Photodynamic tissue adhesion with chlorin(e6) protein conjugates.

Science.gov (United States)

Khadem, J; Veloso, A A; Tolentino, F; Hasan, T; Hamblin, M R

1999-12-01

To test the hypothesis that a photodynamic laser-activated tissue solder would perform better in sealing scleral incisions when the photosensitizer was covalently linked to the protein than when it was noncovalently mixed. Conjugates and mixtures were prepared between the photosensitizer chlorin(e6) and various proteins (albumin, fibrinogen, and gelatin) in different ratios and used to weld penetrating scleral incisions made in human cadaveric eyes. A blue-green (488-514 nm) argon laser activated the adhesive, and the strength of the closure was measured by increasing the intraocular pressure until the wound showed leakage. Both covalent conjugates and noncovalent mixtures showed a light dose-dependent increase in leaking pressure. A preparation of albumin chlorin(e6) conjugate with additional albumin added (2.5 protein to chlorin(e6) molar ratio) showed significantly higher weld strength than other protein conjugates and mixtures. This is the first report of dye-protein conjugates as tissue solders. These conjugates may have applications in ophthalmology.

Human glutathione S-transferase-mediated glutathione conjugation of curcumin and efflux of these conjugates in caco-2 cells

NARCIS (Netherlands)

Usta, M.; Wortelboer, H.M.; Vervoort, J.; Boersma, M.G.; Rietjens, I.M.C.M.; Bladeren, P.J. van; Cnubben, N.H.P.

2007-01-01

Curcumin, an α,β-unsaturated carbonyl compound, reacts with glutathione, leading to the formation of two monoglutathionyl curcumin conjugates. In the present study, the structures of both glutathione conjugates of curcumin were identified by LC-MS and one- and two-dimensional 1H NMR analysis, and

Reconstructing historical radionuclide concentrations along the east coast of Ireland using a compartmental model

International Nuclear Information System (INIS)

Smith, C.N.; Clarke, S.; McDonald, P.; Goshawk, J.A.; Jones, S.R.

2000-01-01

A mathematical model is presented that simulates the annually averaged transport of radionuclides, originating from the BNFL reprocessing plant at Sellafield, throughout the Irish Sea. The model, CUMBRIA77, represents the processes of radionuclide transport and dispersion in the marine environment and allows predictions of radionuclide concentration in various environmental media, including biota, to be made throughout the whole of the Irish Sea. In this paper we describe the use of the model to reconstruct the historical activity concentrations of 137Cs and 239+240Pu in a variety of environmental media in the western Irish Sea and along the Irish east coast back to 1950. This reconstruction exercise is of interest because only limited measurements of 137Cs and 239+240Pu activity are available prior to the 1980s. The predictions were compared to the available measured data to validate their accuracy. The results of the reconstruction indicate that activity concentrations of 137Cs in the western Irish Sea follow a similar, though slightly delayed and smoothed, profile to the discharges from the Sellafield site, with concentrations at the time of peak discharge (the mid-1970s) being around an order of magnitude higher than those measured in the 1980s and 1990s. By contrast, the concentrations of 239+240Pu at the time of peak discharges were similar to those presently measured. These differences reflect the distinct marine chemistries of the two nuclides, in particular the higher propensity of plutonium to bind to sediments leading to extended transport times. Despite these differences in behaviour the doses to Irish seafood consumers from 137Cs remain significantly higher than those from 239+240Pu

DENDRIMER CONJUGATES FOR SELECTIVE OF PROTEIN AGGREGATES

DEFF Research Database (Denmark)

2004-01-01

Dendrimer conjugates are presented, which are formed between a dendrimer and a protein solubilising substance. Such dendrimer conjugates are effective in the treatment of protein aggregate-related diseases (e.g. prion-related diseases). The protein solubilising substance and the dendrimer together...

Radionuclide cisternography: SPECT and 3D-rendering

International Nuclear Information System (INIS)

Henkes, H.; Huber, G.; Piepgras, U.; Hierholzer, J.; Cordes, M.

1991-01-01

Radionuclide cisternography is indicated in the clinical work-up for hydrocephalus, when searching for CSF leaks, and when testing whether or not intracranial cystic lesions are communicating with the adjacent subarachnoid space. This paper demonstrates the feasibility and diagnostic value of SPECT and subsequent 3D surface rendering in addition to conventional rectilinear CSF imaging in eight patients. Planar images allowed the evaluation of CSF circulation and the detection of CSF fistula. They were advantageous in examinations 48 h after application of 111 In-DTPA. SPECT scans, generated 4-24 h after tracer application, were superior in the delineation of basal cisterns, especially in early scans; this was helpful in patients with pooling due to CSF fistula and in cystic lesions near the skull base. A major drawback was the limited image quality of delayed scans, when the SPECT data were degraded by a low count rate. 3D surface rendering was easily feasible from SPECT data and yielded high quality images. The presentation of the spatial distribution of nuclide-contaminated CSF proved especially helpful in the area of the basal cisterns. (orig.) [de

The significance of 123I-BMIPP delayed scintigraphic imaging in cardiac patients.

Science.gov (United States)

Akashi, Yoshihiro J; Kida, Keisuke; Suzuki, Kae; Inoue, Koji; Kawasaki, Kensuke; Yamauchi, Masahiro; Musha, Haruki; Anker, Stefan D

2007-04-25

Earlier studies have not fully investigated the significance of radionuclide planar imaging in cardiac patients using the fatty acid analogue 123I-beta-methyl-iodophenylpentadecanoic acid (123I-BMIPP). This study was to clarify the effectiveness of 123I-BMIPP in assessing the heart-to-mediastinum ratio (H/M) and myocardial washout rate (WR) in patients with heart disease. Myocardial 123I-BMIPP imaging was performed in 33 patients (20 with chronic heart failure [CHF] and 13 with stable angina pectoris [AP]) and 11 control subjects. Myocardial 123I-BMIPP planner images were obtained 30 min (early image) and 4 h (delayed image) after tracer injection. The left ventricular ejection fraction (LVEF) was measured by quantitative gated single photon emission computed tomography. The concentration of plasma brain natriuretic peptide (BNP) was measured before the scintigraphic study. (1) Delayed H/M was much lower in CHF than in AP (1.93 +/- 0.37 vs. 2.21 +/- 0.38, p acid metabolism disorders in patients with heart disease in both masked and unmasked conditions.

Stochastic analysis of radionuclide migration in saturated-unsaturated soils

International Nuclear Information System (INIS)

Kawanishi, Moto

1988-01-01

In Japan, LLRW (low level radioactive wastes) generated from nuclear power plants shall be started to store concentrically in the Shimokita site from 1990, and those could be transformed into land disposal if the positive safety is confirmed. Therefore, it is hoped that the safety assessment method shall be successed for the land disposal of LLRW. In this study, a stochastic model to analyze the radionuclide migration in saturated-unsaturated soils was constructed. The principal results are summarized as follows. 1) We presented a generalized idea for the modeling of the radionuclide migration in saturated-unsaturated soils as an advective-dispersion phenomena followed by the decay of radionuclides and those adsorption/desorption in soils. 2) Based on the radionuclide migration model mentioned above, we developed a stochastic analysis model on radionuclide migration in saturated-unsaturated soils. 3) From the comparison between the simulated results and the exact solution on a few simple one-dimensional advective-dispersion problems of radionuclides, the good validity of this model was confirmed. 4) From the comparison between the simulated results by this model and the experimental results of radionuclide migration in a one-dimensional unsaturated soil column with rainfall, the good applicability was shown. 5) As the stochastic model such as this has several advantages that it is easily able to represent the image of physical phenomena and has basically no numerical dissipation, this model should be more applicable to the analysis of the complicated radionuclide migration in saturated-unsaturated soils. (author)

Preparation of Radiopharmaceuticals Labeled with Metal Radionuclides

Energy Technology Data Exchange (ETDEWEB)

Welch, M.J.

2012-02-16

The overall goal of this project was to develop methods for the production of metal-based radionuclides, to develop metal-based radiopharmaceuticals and in a limited number of cases, to translate these agents to the clinical situation. Initial work concentrated on the application of the radionuclides of Cu, Cu-60, Cu-61 and Cu-64, as well as application of Ga-68 radiopharmaceuticals. Initially Cu-64 was produced at the Missouri University Research Reactor and experiments carried out at Washington University. A limited number of studies were carried out utilizing Cu-62, a generator produced radionuclide produced by Mallinckrodt Inc. (now Covidien). In these studies, copper-62-labeled pyruvaldehyde Bis(N{sup 4}-methylthiosemicarbazonato)-copper(II) was studied as an agent for cerebral myocardial perfusion. A remote system for the production of this radiopharmaceutical was developed and a limited number of patient studies carried out with this agent. Various other copper radiopharmaceuticals were investigated, these included copper labeled blood imaging agents as well as Cu-64 labeled antibodies. Cu-64 labeled antibodies targeting colon cancer were translated to the human situation. Cu-64 was also used to label peptides (Cu-64 octriatide) and this is one of the first applications of a peptide radiolabeled with a positron emitting metal radionuclide. Investigations were then pursued on the preparation of the copper radionuclides on a small biomedical cyclotron. A system for the production of high specific activity Cu-64 was developed and initially the Cu-64 was utilized to study the hypoxic imaging agent Cu-64 ATSM. Utilizing the same target system, other positron emitting metal radionuclides were produced, these were Y-86 and Ga-66. Radiopharmaceuticals were labeled utilizing both of these radionuclides. Many studies were carried out in animal models on the uptake of Cu-ATSM in hypoxic tissue. The hypothesis is that Cu-ATSM retention in vivo is dependent upon the

Radionuclide transfer onto ground surface in surface water flow, 1

International Nuclear Information System (INIS)

Mukai, Masayuki; Takebe, Shinichi; Komiya, Tomokazu; Kamiyama, Hideo

1991-07-01

Radionuclides migration in ground surface water flow is considered to be one of the important path way in the scenario for environmental migration of radionuclides leaked from low level radioactive waste repository. Simulating the slightly sloped surface on which contaminated solution is flowing downward, testing for radionuclide migration on ground surface had been started. As it's first step, an experiment was carried out under the condition of restricted infiltration in order to elucidate the adsorption behavior of radionuclides onto the loamy soil surface in related with hydraulic conditions. Radionuclides concentration change in effluent solution with time and a concentration distribution of radionuclides adsorbed on the ground surface were obtained from several experimental conditions combining the rate and the duration time of the water flow. The radionuclides concentration in the effluent solution was nearly constant during each experimental period, and was reduced under the condition of lower flow rate. The surface distribution of radionuclides concentration showed two distinctive regions. The one was near the inlet vessel where the concentration was promptly reducing, and the other was following the former where the concentration was nearly constant. The characteristic surface distribution of radionuclides concentration can be explained by a two dimensional diffusion model with a first order adsorption reaction, based on the advection of flow rate distribution in perpendicular direction. (author)

Extreme radionuclide accumulation on alpine glaciers in cryoconites

International Nuclear Information System (INIS)

Lettner, H.; Wilflinger, T.; Hubmer, A.K.; Bossew, P.

2008-01-01

Full text: Under environmental conditions when radionuclide fallout will not be diluted by media like soil or water, radionuclides deposited may accumulate to unusual high activities. On glacier surfaces conditions as such exist for aerosols and airborne dust deposited with anthropogenic and natural radionuclides attached on their surfaces. In the course of agglomeration processes initiated by melting and redistribution, these particles may concentrate in small depressions, ice pockets, ablation edges etc. and form substances called cryoconites ('ice dust'). As there is no other matrix than the original aerosol particles, cryoconites are a sink for radionuclides and airborne pollutants and their activity levels are among the highest produced by natural processes observed in environmental media. 137 Cs activities found on glaciers in the Austrian alps are between 255 and 136.000 Bq/kg and predominantly derived from Chernobyl, but also from global fallout. Further anthropogenic radionuclides detected are 134 Cs, 90 Sr, 238,239+240 Pu, 241 Am, 125 Sb, 154 Eu, 60 Co and 207 Bi. In combination with the naturally occurring radionuclides 7 Be and 210 Pb and isotopic ratios such as 134 Cs/ 137 Cs, identification and discrimination of the sources, the nuclear weapon tests and the Chernobyl fallout, can be carried out. (author)

Radionuclide X-ray fluorescence analysis

International Nuclear Information System (INIS)

Cechak, T.

1994-01-01

The author's achievements in the title field are summarized and discussed. The following topics are dealt with: (i) principles of radionuclide X-ray fluorescence analysis; (ii) mathematical methods in X-ray fluorescence analysis; (iii) Ross differential filters; (iv) application of radionuclide X-ray fluorescence analysis in the coal industry (with emphasis on the determination of the ash content, sulfur content, and arsenic content of coal); and (v) evaluation of the X-ray fluorescence analyzer from the radiological safety point of view. (P.A.)

Radionuclide generators for biomedical applications

International Nuclear Information System (INIS)

Finn, R.D.; Molinski, V.J.; Hupf, H.B.; Kramer, H.

1983-10-01

This document reviews the chemical literature of those radionuclide generators that have gained or appear to possess utility in medical imaging. The text represents a conscientious effort to peruse the scientific literature through 1980. The intent of this work is to provide a reference point for the investigator who is interested in the development of a particular generator system and the refinements which have been reported. Moreover, the incorporation of the particular daughter radionuclide into a suitable radiodiagnostic agent is presented

A conserved helicase processivity factor is needed for conjugation and replication of an integrative and conjugative element.

Directory of Open Access Journals (Sweden)

Jacob Thomas

Full Text Available Integrative and conjugative elements (ICEs are agents of horizontal gene transfer and have major roles in evolution and acquisition of new traits, including antibiotic resistances. ICEs are found integrated in a host chromosome and can excise and transfer to recipient bacteria via conjugation. Conjugation involves nicking of the ICE origin of transfer (oriT by the ICE-encoded relaxase and transfer of the nicked single strand of ICE DNA. For ICEBs1 of Bacillus subtilis, nicking of oriT by the ICEBs1 relaxase NicK also initiates rolling circle replication. This autonomous replication of ICEBs1 is critical for stability of the excised element in growing cells. We found a conserved and previously uncharacterized ICE gene that is required for conjugation and replication of ICEBs1. Our results indicate that this gene, helP (formerly ydcP, encodes a helicase processivity factor that enables the host-encoded helicase PcrA to unwind the double-stranded ICEBs1 DNA. HelP was required for both conjugation and replication of ICEBs1, and HelP and NicK were the only ICEBs1 proteins needed for replication from ICEBs1 oriT. Using chromatin immunoprecipitation, we measured association of HelP, NicK, PcrA, and the host-encoded single-strand DNA binding protein Ssb with ICEBs1. We found that NicK was required for association of HelP and PcrA with ICEBs1 DNA. HelP was required for association of PcrA and Ssb with ICEBs1 regions distal, but not proximal, to oriT, indicating that PcrA needs HelP to progress beyond nicked oriT and unwind ICEBs1. In vitro, HelP directly stimulated the helicase activity of the PcrA homologue UvrD. Our findings demonstrate that HelP is a helicase processivity factor needed for efficient unwinding of ICEBs1 for conjugation and replication. Homologues of HelP and PcrA-type helicases are encoded on many known and putative ICEs. We propose that these factors are essential for ICE conjugation, replication, and genetic stability.

2014 LANL Radionuclide Air Emissions Report

Energy Technology Data Exchange (ETDEWEB)

Fuehne, David Patrick [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

2015-07-21

This report describes the emissions of airborne radionuclides from operations at Los Alamos National Laboratory (LANL) for calendar year 2014, and the resulting off-site dose from these emissions. This document fulfills the requirements established by the National Emissions Standards for Hazardous Air Pollutants in 40 CFR 61, Subpart H – Emissions of Radionuclides other than Radon from Department of Energy Facilities, commonly referred to as the Radionuclide NESHAP or Rad-NESHAP. Compliance with this regulation and preparation of this document is the responsibility of LANL’s RadNESHAP compliance program, which is part of the Environmental Protection Division. The information in this report is required under the Clean Air Act and is being submitted to the U.S. Environmental Protection Agency (EPA) Region 6.

Conjugate Gaze Palsies

Science.gov (United States)

... version Home Brain, Spinal Cord, and Nerve Disorders Cranial Nerve Disorders Conjugate Gaze Palsies Horizontal gaze palsy Vertical ... Version. DOCTORS: Click here for the Professional Version Cranial Nerve Disorders Overview of the Cranial Nerves Internuclear Ophthalmoplegia ...

Assessment Lumboperitoneal or Ventriculoperitoneal Shunt Patency by Radionuclide Technique: A Review Experience Cases

International Nuclear Information System (INIS)

Chiewvit, Sunanta; Nuntaaree, Sarun; Kanchaanapiboon, Potjanee; Chiewvit, Pipat

2014-01-01

Hydrocephalus-related symptoms that worsen after shunt placement may indicate a malfunctioning or obstructed shunt. The assessment of shunt patency and site of obstruction is important for planning of treatment. The radionuclide cerebrospinal fluid (CSF) shunt study provides a simple, effective, and low-radiation-dose method of assessing CSF shunt patency. The radionuclide CSF shuntography is a useful tool in the management of patients presenting with shunt-related problems not elucidated by conventional radiological examination. This article described the imaging technique of ventriculoperitoneal (VP) shunt and lumbar puncture (LP) shunt. The normal finding, abnormal finding of completed obstruction and partial obstruction is present by our cases experience. The radiopharmaceutical (Tc-99m diethylenetriaminepentaacetic acid) was injected via the reservoir for VP shunt and via lumbar puncture needle in subarachnoid space for LP shunt, then serial image in the head and abdominal area. The normal function of VP and LP shunt usually rapid spillage of the radioactivity in the abdominal cavity diffusely. The patent proximal tube VP shunt demonstrates ventricular reflux. The early image of patent LP shunt reveals no activity in the ventricular system contrast to distal LP shunt reveals early reflux of activity in the ventricular system. The completed distal VP and LP shunt obstruction show absence of tracer in the peritoneal area or markedly delayed appearance of abdominal activity. The partial distal VP and LP shunt obstruction recognized by slow transit or accumulation of tracer at the distal end or focal tracer in the peritoneal cavity near the tip of distal shunt. The images of the normal and abnormal CSF shunt as describe before are present in the full paper. Radionuclide CSF shuntography is a reliable and simple procedure for assessment shunt patency

Inventories of selected radionuclides in the oceans

International Nuclear Information System (INIS)

1988-10-01

In March 1984 an ad hoc Review Committee composed of senior experts in the marine radioactivity field made recommendations that ''the Monaco Laboratory should be engaged in compiling and evaluating the input of radionuclides into the marine environment''. The Committee recommended that work should commence on selected radionuclides, viz., 14 C, caesium isotopes, plutonium isotopes, 210 Po and 210 Pb followed by 226 Ra. Depending on the radionuclides involved the assistance of competent experts from outside as well as inside the IAEA was sought. The present document is a product of the work carried out within the framework of the above-mentioned task and contains reports on 14 C, 90 Sr, 137 Cs, 238 Pu, 239+240 Pu, 210 Pb, 210 Po and 226 Ra. Although the estimation of the inventory in the marine environment and related input and output fluxes, is the same for all radionuclides concerned, different approaches were followed to achieve this objective. These approaches depended on the geochemical characteristics of the radionuclides and the availability of data for different times and locations. For regions where data were lacking, extrapolation on the basis of specific assumptions has often been necessary. As the work was initiated during the pre-Chernobyl period, the radionuclides derived from the Chernobyl incident were not, in general, considered. Since the work for preparing the forthcoming report of the UNSCEAR is scheduled to be completed by 1991, it is hoped that the information contained in this volume will be beneficial. Refs, figs and tabs

A study of the colonic transit function by dual radionuclide colon scintigraphy

International Nuclear Information System (INIS)

Yang Weidong; Sun Buzhou; Song Changyi; Lu Jinyan; Wang Shejiao; Zheng Xianghong; Huang Lin; Lei Yamei

1999-01-01

Objective: To establish a new, simple and noninvasive method which can quantitatively analyze the colonic transit function by dual radionuclide colon scintigraphy. Methods: 24 patients with constipation and 32 normal controls were studied. Na 131 I was sealed into capsule made by polyvinylchloride which can not be digested and absorbed in gastrointestinal tract. Patients and normal volunteers swallow 131 I capsules and drink 99 Tc m labelled sulfur colloid solution at the same time. The static image was acquired at the regular time, then calculate the Geometric Center values (GC). Results: 1) The capsules can be clearly located through the colonic contour shown by 99 Tc m labeled sulfur colloid when it reached the large bowel. 2) The transiting time from mouth to cecum, through colon and through whole gastrointestinal in normal people were (6.61 +- 1.94), (36.61 +- 10.51) and (42.72 +- 10.02) h, respectively, in constipation group were (8.03 +- 3.63), (65.50 +- 28.40) and (74.05 +- 28.17) h, respectively. There was no significant difference (P > 0.05) in two groups compared with each other. But the transiting time through colon and whole gastrointestinal in constipation was slower than that in normal people, with significant difference (P < 0.01). 3) Through examination the colonic transit abnormality can be divided into three patterns: whole colon transit delay, right-colon transit delay and left-colon transit delay. Conclusions: This method is a simple, physiologic and quantitative in evaluating the colonic transit, it can also stage the colonic dyskinesia of the patients

New radionuclide generator systems for use in nuclear medicine

International Nuclear Information System (INIS)

Atcher, R.W.

1979-01-01

A current emphasis in nuclear medicine is to better match the physical lifetime of the radionuclides used in vivo for diagnosis and treatment to the biological lifetime of the diagnostic procedure or to minimize radiation dose to areas other than those to be treated. In many cases the biological lifetime is on the order of minutes. Since the direct production of radionuclides with half lives of minutes requires the user to be near a suitable reactor or accelerator, this study was undertaken to produce short-lived radionuclides indirectly. If a long-lived radionuclide decays into a short-lived radionuclide, quick separation of the daughter activity from the parent enables the user to have a short-lived daughter while freeing him from the constraint of proximity to a cyclotron. Systems where a short-lived daughter is separated from a long-lived parent are called radionuclide generators. Two generator systems were developed for use in nuclear medicine, one in diagnostic work and the other for therapeutic work. The yield and breakthrough characteristics were within the limits required to minimize unnecessary radiation exposure in patients. Two parent radionuclides were produced using 4 He beams available from medium energy cyclotrons. The yield was high enough to produce generators that would be useful in clinical applications

Development of a transportable system for radionuclide analysis

International Nuclear Information System (INIS)

Cunningham, W.C.; Anderson, D.L.; Lamont, W.H.; South, P.K.; Rury, M.A.; Beachley, G.M.; Ondov, J.M.

2008-01-01

Transportable radioanalytical systems were assembled and tested for quantitative determination of γ-emitting radionuclides and screening of β- emitting radionuclides. Standard operating procedures (SOPs), including instructions for assembly, disassembly, operation, sample collection and analysis, and all other procedures needed, were developed. Foods, as well as National Institute of Standards and Technology, International Atomic Energy Agency, and in-house Reference Materials were analyzed. An SOP for γ-emitting radionuclides was successfully tested at 3 locations. (author)

Hydrology/Radionuclide Migration Program and related research activities

International Nuclear Information System (INIS)

Jones, M.A.

1992-02-01

This report presents the results of technical studies conducted under the Hydrology/Radionuclide Migration Program (HRMP) at the Nevada Test Site (NTS) for the period of October 1, 1985 through September 30, 1986. The HRMP was initiated in 1973 as the Radionuclide Migration Program to study and better understand the hydrologic systems of the NTS and potential movement and rates of movement of radionuclides and other contaminants injected into these systems by underground nuclear testing

Synthesis of Mikto-Arm Star Peptide Conjugates.

Science.gov (United States)

Koo, Jin Mo; Su, Hao; Lin, Yi-An; Cui, Honggang

2018-01-01

Mikto-arm star peptide conjugates are an emerging class of self-assembling peptide-based structural units that contain three or more auxiliary segments of different chemical compositions and/or functionalities. This group of molecules exhibit interesting self-assembly behavior in solution due to their chemically asymmetric topology. Here we describe the detailed procedure for synthesis of an ABC Mikto-arm star peptide conjugate in which two immiscible entities (a saturated hydrocarbon and a hydrophobic and lipophobic fluorocarbon) are conjugated onto a short β-sheet forming peptide sequence, GNNQQNY, derived from the Sup35 prion, through a lysine junction. Automated and manual Fmoc-solid phase synthesis techniques are used to synthesize the Mikto-arm star peptide conjugates, followed by HPLC purification. We envision that this set of protocols can afford a versatile platform to synthesize a new class of peptidic building units for diverse applications.

Fullerene-biomolecule conjugates and their biomedicinal applications.

Science.gov (United States)

Yang, Xinlin; Ebrahimi, Ali; Li, Jie; Cui, Quanjun

2014-01-01

Fullerenes are among the strongest antioxidants and are characterized as "radical sponges." The research on biomedicinal applications of fullerenes has achieved significant progress since the landmark publication by Friedman et al in 1993. Fullerene-biomolecule conjugates have become an important area of research during the past 2 decades. By a thorough literature search, we attempt to update the information about the synthesis of different types of fullerene-biomolecule conjugates, including fullerene-containing amino acids and peptides, oligonucleotides, sugars, and esters. Moreover, we also discuss in this review recently reported data on the biological and pharmaceutical utilities of these compounds and some other fullerene derivatives of biomedical importance. While within the fullerene-biomolecule conjugates, in which fullerene may act as both an antioxidant and a carrier, specific targeting biomolecules conjugated to fullerene will undoubtedly strengthen the delivery of functional fullerenes to sites of clinical interest.

Gold Nanoparticle Conjugation Enhances the Antiacanthamoebic Effects of Chlorhexidine

Science.gov (United States)

Aqeel, Yousuf; Siddiqui, Ruqaiyyah; Anwar, Ayaz; Shah, Muhammad Raza

2015-01-01

Acanthamoeba keratitis is a serious infection with blinding consequences and often associated with contact lens wear. Early diagnosis, followed by aggressive topical application of drugs, is a prerequisite in successful treatment, but even then prognosis remains poor. Several drugs have shown promise, including chlorhexidine gluconate; however, host cell toxicity at physiologically relevant concentrations remains a challenge. Nanoparticles, subcolloidal structures ranging in size from 10 to 100 nm, are effective drug carriers for enhancing drug potency. The overall aim of the present study was to determine whether conjugation with gold nanoparticles enhances the antiacanthamoebic potential of chlorhexidine. Gold-conjugated chlorhexidine nanoparticles were synthesized. Briefly, gold solution was mixed with chlorhexidine and reduced by adding sodium borohydride, resulting in an intense deep red color, indicative of colloidal gold-conjugated chlorhexidine nanoparticles. The synthesis was confirmed using UV-visible spectrophotometry that shows a plasmon resonance peak of 500 to 550 nm, indicative of gold nanoparticles. Further characterization using matrix-assisted laser desorption ionization-mass spectrometry showed a gold-conjugated chlorhexidine complex at m/z 699 ranging in size from 20 to 100 nm, as determined using atomic force microscopy. To determine the amoebicidal and amoebistatic effects, amoebae were incubated with gold-conjugated chlorhexidine nanoparticles. For controls, amoebae also were incubated with gold and silver nanoparticles alone, chlorhexidine alone, neomycin-conjugated nanoparticles, and neomycin alone. The findings showed that gold-conjugated chlorhexidine nanoparticles exhibited significant amoebicidal and amoebistatic effects at 5 μM. Amoebicidal effects were observed by parasite viability testing using a Trypan blue exclusion assay and flow-cytometric analysis using propidium iodide, while amoebistatic effects were observed using growth

Analytical characterization of polymer-drug conjugates

International Nuclear Information System (INIS)

Rizzo, V.; Gigli, M.; Pinciroli, V.

1998-01-01

A few polymeric conjugates of antitumor drugs have been recently developed in view of possible therapeutic advantages: solubilization of sparingly soluble drugs in water, improvement of therapeutic index, organ targeting through a second chemical species bound to the same polymeric chain. In this article it's described the analytical approach used in the characterization of the conjugates for chemical identity, purity and strength of the contained active ingredient. The techniques are: high field NMR and size exclusion chromatography with non-aqueous mobile phase for identity; selective hydrolysis and HPLC for strength and purity. A complete and reliable picture is thus obtained both for qualitative and for quantitative aspects. This is an important step forward in the direction of further development and marketing of polymer-drug conjugates [it

Conjugate gradient algorithms using multiple recursions

Energy Technology Data Exchange (ETDEWEB)

Barth, T.; Manteuffel, T.

1996-12-31

Much is already known about when a conjugate gradient method can be implemented with short recursions for the direction vectors. The work done in 1984 by Faber and Manteuffel gave necessary and sufficient conditions on the iteration matrix A, in order for a conjugate gradient method to be implemented with a single recursion of a certain form. However, this form does not take into account all possible recursions. This became evident when Jagels and Reichel used an algorithm of Gragg for unitary matrices to demonstrate that the class of matrices for which a practical conjugate gradient algorithm exists can be extended to include unitary and shifted unitary matrices. The implementation uses short double recursions for the direction vectors. This motivates the study of multiple recursion algorithms.

EBS Radionuclide Transport Abstraction

International Nuclear Information System (INIS)

J.D. Schreiber

2005-01-01

The purpose of this report is to develop and analyze the engineered barrier system (EBS) radionuclide transport abstraction model, consistent with Level I and Level II model validation, as identified in ''Technical Work Plan for: Near-Field Environment and Transport: Engineered Barrier System: Radionuclide Transport Abstraction Model Report Integration'' (BSC 2005 [DIRS 173617]). The EBS radionuclide transport abstraction (or EBS RT Abstraction) is the conceptual model used in the total system performance assessment for the license application (TSPA-LA) to determine the rate of radionuclide releases from the EBS to the unsaturated zone (UZ). The EBS RT Abstraction conceptual model consists of two main components: a flow model and a transport model. Both models are developed mathematically from first principles in order to show explicitly what assumptions, simplifications, and approximations are incorporated into the models used in the TSPA-LA. The flow model defines the pathways for water flow in the EBS and specifies how the flow rate is computed in each pathway. Input to this model includes the seepage flux into a drift. The seepage flux is potentially split by the drip shield, with some (or all) of the flux being diverted by the drip shield and some passing through breaches in the drip shield that might result from corrosion or seismic damage. The flux through drip shield breaches is potentially split by the waste package, with some (or all) of the flux being diverted by the waste package and some passing through waste package breaches that might result from corrosion or seismic damage. Neither the drip shield nor the waste package survives an igneous intrusion, so the flux splitting submodel is not used in the igneous scenario class. The flow model is validated in an independent model validation technical review. The drip shield and waste package flux splitting algorithms are developed and validated using experimental data. The transport model considers

EBS Radionuclide Transport Abstraction

Energy Technology Data Exchange (ETDEWEB)

J.D. Schreiber

2005-08-25

The purpose of this report is to develop and analyze the engineered barrier system (EBS) radionuclide transport abstraction model, consistent with Level I and Level II model validation, as identified in ''Technical Work Plan for: Near-Field Environment and Transport: Engineered Barrier System: Radionuclide Transport Abstraction Model Report Integration'' (BSC 2005 [DIRS 173617]). The EBS radionuclide transport abstraction (or EBS RT Abstraction) is the conceptual model used in the total system performance assessment for the license application (TSPA-LA) to determine the rate of radionuclide releases from the EBS to the unsaturated zone (UZ). The EBS RT Abstraction conceptual model consists of two main components: a flow model and a transport model. Both models are developed mathematically from first principles in order to show explicitly what assumptions, simplifications, and approximations are incorporated into the models used in the TSPA-LA. The flow model defines the pathways for water flow in the EBS and specifies how the flow rate is computed in each pathway. Input to this model includes the seepage flux into a drift. The seepage flux is potentially split by the drip shield, with some (or all) of the flux being diverted by the drip shield and some passing through breaches in the drip shield that might result from corrosion or seismic damage. The flux through drip shield breaches is potentially split by the waste package, with some (or all) of the flux being diverted by the waste package and some passing through waste package breaches that might result from corrosion or seismic damage. Neither the drip shield nor the waste package survives an igneous intrusion, so the flux splitting submodel is not used in the igneous scenario class. The flow model is validated in an independent model validation technical review. The drip shield and waste package flux splitting algorithms are developed and validated using experimental data. The transport

EBS Radionuclide Transport Abstraction

Energy Technology Data Exchange (ETDEWEB)

J. Prouty

2006-07-14

The purpose of this report is to develop and analyze the engineered barrier system (EBS) radionuclide transport abstraction model, consistent with Level I and Level II model validation, as identified in Technical Work Plan for: Near-Field Environment and Transport: Engineered Barrier System: Radionuclide Transport Abstraction Model Report Integration (BSC 2005 [DIRS 173617]). The EBS radionuclide transport abstraction (or EBS RT Abstraction) is the conceptual model used in the total system performance assessment (TSPA) to determine the rate of radionuclide releases from the EBS to the unsaturated zone (UZ). The EBS RT Abstraction conceptual model consists of two main components: a flow model and a transport model. Both models are developed mathematically from first principles in order to show explicitly what assumptions, simplifications, and approximations are incorporated into the models used in the TSPA. The flow model defines the pathways for water flow in the EBS and specifies how the flow rate is computed in each pathway. Input to this model includes the seepage flux into a drift. The seepage flux is potentially split by the drip shield, with some (or all) of the flux being diverted by the drip shield and some passing through breaches in the drip shield that might result from corrosion or seismic damage. The flux through drip shield breaches is potentially split by the waste package, with some (or all) of the flux being diverted by the waste package and some passing through waste package breaches that might result from corrosion or seismic damage. Neither the drip shield nor the waste package survives an igneous intrusion, so the flux splitting submodel is not used in the igneous scenario class. The flow model is validated in an independent model validation technical review. The drip shield and waste package flux splitting algorithms are developed and validated using experimental data. The transport model considers advective transport and diffusive transport

EBS Radionuclide Transport Abstraction

International Nuclear Information System (INIS)

J. Prouty

2006-01-01

The purpose of this report is to develop and analyze the engineered barrier system (EBS) radionuclide transport abstraction model, consistent with Level I and Level II model validation, as identified in Technical Work Plan for: Near-Field Environment and Transport: Engineered Barrier System: Radionuclide Transport Abstraction Model Report Integration (BSC 2005 [DIRS 173617]). The EBS radionuclide transport abstraction (or EBS RT Abstraction) is the conceptual model used in the total system performance assessment (TSPA) to determine the rate of radionuclide releases from the EBS to the unsaturated zone (UZ). The EBS RT Abstraction conceptual model consists of two main components: a flow model and a transport model. Both models are developed mathematically from first principles in order to show explicitly what assumptions, simplifications, and approximations are incorporated into the models used in the TSPA. The flow model defines the pathways for water flow in the EBS and specifies how the flow rate is computed in each pathway. Input to this model includes the seepage flux into a drift. The seepage flux is potentially split by the drip shield, with some (or all) of the flux being diverted by the drip shield and some passing through breaches in the drip shield that might result from corrosion or seismic damage. The flux through drip shield breaches is potentially split by the waste package, with some (or all) of the flux being diverted by the waste package and some passing through waste package breaches that might result from corrosion or seismic damage. Neither the drip shield nor the waste package survives an igneous intrusion, so the flux splitting submodel is not used in the igneous scenario class. The flow model is validated in an independent model validation technical review. The drip shield and waste package flux splitting algorithms are developed and validated using experimental data. The transport model considers advective transport and diffusive transport

Four-wave mixing and phase conjugation in plasmas

International Nuclear Information System (INIS)

Federici, J.F.

1989-01-01

Nonlinear optical effects such as Stimulated Brillouin Scattering, Stimulated Raman Scattering, self-focusing, wave-mixing, parametric mixing, etc., have a long history in plasma physics. Recently, four-wave mixing in plasmas and its applications to phase conjugation has been extensively studied. Although four-wave mixing (FWM), using various nonlinear mediums, has many practical applications in the visible regime, no successful attempt has been made to study or demonstrate FWM for wavelengths longer than 10μm. Plasmas as phase conjugate mirrors have received considerable attention since they become more efficient at longer wavelengths (far-infrared to microwave). The purpose of this thesis is to study various fundamental issues which concern the suitability of plasmas for four-wave mixing and phase conjugation. The major contributions of this thesis are the identification and study of thermal and ionization nonlinearities as potential four-wave mixing and phase conjugation mechanisms and the study of the affect of density inhomogeneities on the FWM process. Using a fluid description for the plasma, this thesis demonstrates that collisional heating generates a thermal force which substantially enhances the phase conjugate reflectivity. The prospect of using a novel ionization nonlinearity in weakly ionized plasmas for wave-mixing and phase conjugation is discussed. The ionization nonlinearity arises from localized heating of the plasma by the beat-wave. Wherever, the local temperature is increased, a plasma density grating is produced due to increased electron-impact ionization. Numerical estimates of the phase conjugate reflectivity indicate reflectivities in the range of 10 -4 -10 -3 are possible in a weakly ionized steady-state gas discharge plasma

Improving global laboratory capabilities for emergency radionuclide bioassay

International Nuclear Information System (INIS)

Li, C.; Jourdain, J.; Kramer, G. H.

2012-01-01

During a radiological or nuclear emergency, first-responders and the general public may be internally contaminated with the radionuclide(s) involved. A timely radionuclide bioassay provides important information about contamination, for subsequent dose assessment and medical management. Both technical and operational gaps are discussed in this paper. As many people may need to be assessed in a short period of time, any single laboratory may find its capabilities insufficient. Laboratories from other regions or other countries may be called upon for assistance. This paper proposes a road-map to improve global capabilities in emergency radionuclide bioassay, suggesting a phased approach for establishing a global laboratory network. Existing international collaboration platforms could provide the base on which to build such a network. (authors)

Conjugation of the CRM197-inulin conjugate significantly increases the immunogenicity of Mycobacterium tuberculosis CFP10-TB10.4 fusion protein.

Science.gov (United States)

Hu, Shun; Yu, Weili; Hu, Chunyang; Wei, Dong; Shen, Lijuan; Hu, Tao; Yi, Youjin

2017-11-01

Mycobacterium tuberculosis (Mtb) is a serious fatal pathogen that causes tuberculosis (TB). Effective vaccination is urgently needed to deal with the serious threat from TB. Mtb-secreted protein antigens are important virulence determinants of Mtb with poor immunogenicity. Adjuvants and antigen delivery systems are thus highly desired to improve the immunogenicity of protein antigens. Inulin is a biocompatible polysaccharide (PS) adjuvant that can stimulate a strong cellular and humoral immunity. Bacterial capsular PS and haptens have been conjugated with cross-reacting material 197 (CRM 197 ) to improve their immunogenicity. CFP10 and TB10.4 were two Mtb-secreted immunodominant protein antigens. A CFP10-TB10.4 fusion protein (CT) was used as the antigen for covalent conjugation with the CRM 197 -inulin conjugate (CRM-inu). The resultant conjugate (CT-CRM-inu) elicited high CT-specific IgG titers, stimulated splenocyte proliferation and provoked the secretion of Th1-type and Th2-type cytokines. Conjugation with CRM-inu significantly prolonged the systemic circulation of CT and exposure to the immune system. Moreover, CT-CRM-inu showed no apparent toxicity to cardiac, hepatic and renal functions. Thus, conjugation of CT with CRM-inu provided an effective strategy for development of protein-based vaccines against Mtb infection. Copyright © 2017 Elsevier Ltd. All rights reserved.

Radionuclide techniques for brain imaging

International Nuclear Information System (INIS)

Cowan, R.J.; Moody, D.M.

1984-01-01

Over the past decade, many of the prime indications for radionuclide brain scanning have become instead indications for CCT, and nuclear medicine studies of the brain have assumed more of a complementary, supportive role. However, there is great promise for improvement in central nervous system radionuclide applications with advances anticipated in both radiopharmaceuticals and instrumentation. Nuclear medicine is continuing to function as a powerful research tool and, in the relatively near future, may regain its role as a major clinical test of the central nervous system

Bactericidal Specificity and Resistance Profile of Poly(Quaternary Ammonium) Polymers and Protein-Poly(Quaternary Ammonium) Conjugates.

Science.gov (United States)

Ji, Weihang; Koepsel, Richard R; Murata, Hironobu; Zadan, Sawyer; Campbell, Alan S; Russell, Alan J

2017-08-14

Antibacterial polymers are potentially powerful biocides that can destroy bacteria on contact. Debate in the literature has surrounded the mechanism of action of polymeric biocides and the propensity for bacteria to develop resistance to them. There has been particular interest in whether surfaces with covalently coupled polymeric biocides have the same mechanism of action and resistance profile as similar soluble polymeric biocides. We designed and synthesized a series of poly(quaternary ammonium) polymers, with tailorable molecular structures and architectures, to engineer their antibacterial specificity and their ability to delay the development of bacterial resistance. These linear poly(quaternary ammonium) homopolymers and block copolymers, generated using atom transfer radical polymerization, had structure-dependent antibacterial specificity toward Gram positive and negative bacterial species. When single block copolymers contained two polymer segments of differing antibacterial specificity, the polymer combined the specificities of its two components. Nanoparticulate human serum albumin-poly(quaternary ammonium) conjugates of these same polymers, synthesized via "grafting from" atom transfer radical polymerization, were strongly biocidal and also exhibited a marked decrease in the rate of bacterial resistance development relative to linear polymers. These protein-biocide conjugates mimicked the behavior of surface-presented polycationic biocides rather than their nonproteinaceous counterparts.

Relating β+ radionuclides' properties by order theory

International Nuclear Information System (INIS)

Quintero, N.Y.; Guillermo Restrepo; Cohen, I.M.; Universidad Tecnologica Nacional, Buenos Aires

2013-01-01

We studied 27 β + radionuclides taking into account some of their variants encoding information of their production, such as integral yield, threshold energy and energy of projectiles used to generate them; these radionuclides are of current use in clinical diagnostic imaging by positron emission tomography (PET). The study was conducted based on physical, physico-chemical, nuclear, dosimetric and quantum properties, which characterise the β + radionuclides selected, with the aim of finding meaningful relationships among them. In order to accomplish this objective the mathematical methodology known as formal concept analysis was employed. We obtained a set of logical assertions (rules) classified as implications and associations, for the set of β + radionuclides considered. Some of them show that low mass defect is related to high and medium values of maximum β + energy, and with even parity and low mean lives; all these parameters are associated to the dose received by a patient subjected to a PET analysis. (author)

Metabolic transformation of radionuclides in marine organisms

International Nuclear Information System (INIS)

Koyanagi, Taku

1987-01-01

Physico-chemical form of radionuclides is one of the important factors governing the concentration by marine organisms, whereas biological activities affect the existing states of radionuclides especially in coastal waters. Radioiodine in the form of iodate which is predominant species in seawater is reduced to iodide ion by biological activities and concentration factor of iodide is an order of magnitude higher than those of iodate. Extremely high accumulation of transition elements, actinides, or natural radionuclides in branchial heart of octopus is explained by the fuction of adenochrome, a glandular pigment in the organ as a natural complexing agent, and similar metal-binding proteins with relatively low molecular weight have been found in various marine invertebrates. High accumulation of some elements also found in mollusk kidney is considered to be caused by the intracellular concretions composed of calcium phosphate. All these biological processes suggest the significance of further investigations on metabolic transformation of radionuclides in marine organisms. (author)

O:2-CRM(197) conjugates against Salmonella Paratyphi A.

Science.gov (United States)

Micoli, Francesca; Rondini, Simona; Gavini, Massimiliano; Lanzilao, Luisa; Medaglini, Donata; Saul, Allan; Martin, Laura B

2012-01-01

Enteric fevers remain a common and serious disease, affecting mainly children and adolescents in developing countries. Salmonella enterica serovar Typhi was believed to cause most enteric fever episodes, but several recent reports have shown an increasing incidence of S. Paratyphi A, encouraging the development of a bivalent vaccine to protect against both serovars, especially considering that at present there is no vaccine against S. Paratyphi A. The O-specific polysaccharide (O:2) of S. Paratyphi A is a protective antigen and clinical data have previously demonstrated the potential of using O:2 conjugate vaccines. Here we describe a new conjugation chemistry to link O:2 and the carrier protein CRM(197), using the terminus 3-deoxy-D-manno-octulosonic acid (KDO), thus leaving the O:2 chain unmodified. The new conjugates were tested in mice and compared with other O:2-antigen conjugates, synthesized adopting previously described methods that use CRM(197) as carrier protein. The newly developed conjugation chemistry yielded immunogenic conjugates with strong serum bactericidal activity against S. Paratyphi A.

O:2-CRM(197 conjugates against Salmonella Paratyphi A.

Directory of Open Access Journals (Sweden)

Francesca Micoli

Full Text Available Enteric fevers remain a common and serious disease, affecting mainly children and adolescents in developing countries. Salmonella enterica serovar Typhi was believed to cause most enteric fever episodes, but several recent reports have shown an increasing incidence of S. Paratyphi A, encouraging the development of a bivalent vaccine to protect against both serovars, especially considering that at present there is no vaccine against S. Paratyphi A. The O-specific polysaccharide (O:2 of S. Paratyphi A is a protective antigen and clinical data have previously demonstrated the potential of using O:2 conjugate vaccines. Here we describe a new conjugation chemistry to link O:2 and the carrier protein CRM(197, using the terminus 3-deoxy-D-manno-octulosonic acid (KDO, thus leaving the O:2 chain unmodified. The new conjugates were tested in mice and compared with other O:2-antigen conjugates, synthesized adopting previously described methods that use CRM(197 as carrier protein. The newly developed conjugation chemistry yielded immunogenic conjugates with strong serum bactericidal activity against S. Paratyphi A.

The main trends in clinical use of radionuclides in oncology

International Nuclear Information System (INIS)

Agranat, V.Z.

1979-01-01

The main trends of using radionuclide methods in clinical oncology are shown. Two main aspects of using radionuclide methods are pointed out: radionuclide investigation of the primary tumour as ''local'' manifestation of the cancer disease, radionuclide investigation of the body ''response'' to the tumour process. Each of the aspects of the problem is briefly considered on some examples. Examples of positive scintigraphy of tumours are given. It is shown that tumorotropic properties of some radionuclides make possible using visualization methods realizing the differential diagnosis of some tumours. Considered are direct and indirect signs which allow determining the presence of metastases and testifying to the tumour process spread

Comparison of the pharmacological and biological properties of HPMA copolymer-pirarubicin conjugates: A single-chain copolymer conjugate and its biodegradable tandem-diblock copolymer conjugate

Czech Academy of Sciences Publication Activity Database

Etrych, Tomáš; Tsukigawa, K.; Nakamura, H.; Chytil, Petr; Fang, J.; Ulbrich, Karel; Otagiri, M.; Maeda, H.

2017-01-01

Roč. 106, 30 August (2017), s. 10-19 ISSN 0928-0987 R&D Projects: GA ČR(CZ) GA15-02986S; GA MŠk(CZ) LQ1604; GA MŠk(CZ) ED1.1.00/02.0109 Grant - others:AV ČR,Japan Society for the Promotion of Science(CZ) JSPS-16-05 Program:Bilaterální spolupráce Institutional support: RVO:61389013 Keywords : pirarubicin * PHPMA conjugate * tandem-diblock PHPMA conjugate Subject RIV: FR - Pharmacology ; Medidal Chemistry OBOR OECD: Pharmacology and pharmacy Impact factor: 3.756, year: 2016

Radionuclide concentrations in white sturgeon from the Columbia River

International Nuclear Information System (INIS)

Dauble, D.D.; Price, K.R.; Poston, T.M.

1993-11-01

The objectives of this study were to (1) review and summarize historical data on radionuclide concentrations in white sturgeon from the Columbia River, (2) determine present-day radionuclide tissue burdens from different locations in the Columbia River, and (3) compare historical data with current data. We first reviewed and summarized the historical literature on radionuclide concentrations in white sturgeon from the Hanford Reach. Field studies were then conducted to evaluate the relationship among sample locations, age/length of white sturgeon, and present radionuclide tissue burdens. Results and comparisons are discussed in the remainder of this report

Radionuclide Therapies in Molecular Imaging and Precision Medicine.

Science.gov (United States)

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

2017-01-01

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

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

Science.gov (United States)

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

2016-01-01

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

CRRIS, Health Risk Assessment from Atmospheric Releases of Radionuclides

International Nuclear Information System (INIS)

1999-01-01

1 - Description of program or function: CRRIS consists of eight fully integrated computer codes which calculate environmental transport of atmospheric releases of radionuclides and resulting doses and health risks to individuals or populations. Each code may be used alone for various assessment applications. Because of its modular structure, CRRIS allows assessments to be tailored to the user's needs. Radionuclides are handled by CRRIS either in terms of the released radionuclides or the exposure radionuclides which consist of both the released nuclides and decay products that build up during environmental transport. Atmospheric dispersion calculations are performed by the ANEMOS computer code for distances less than 100 km and the RETADD-II computer code regional-scale distances. Both codes estimate annual-average air concentrations and ground deposition rates by location. SUMIT will translate and scale multiple ANEMOS runs onto a master grid. TERRA reads radionuclide air concentrations and deposition rates to estimate concentrations of radionuclides in food and surface soil. Radiologic decay and ingrowth, soil leaching, and transport through the food chain are included in the calculations. MLSOIL computes an effective radionuclide ground-surface concentration to be used in computing external health effects. The five-layer model of radionuclide transport through soil in MLSOIL provides an alternative to the single-layer model used in TERRA. DFSOIL computes dose factors used in MLSOIL to compute doses from the five soil layers and from the ground surface. ANDROS reads environmental concentrations of radionuclides computed by the other CRRIS codes and produces tables of doses and risks to individuals or populations from atmospheric releases of radionuclides. 2 - Method of solution: SUMIT performs geometric interpolation. TERRA and MLSOIL are terrestrial transport compartment models. DFSOIL computes soil-layer-specific dose factors based on the point-kernel method

Integrated circuits based on conjugated polymer monolayer.

Science.gov (United States)

Li, Mengmeng; Mangalore, Deepthi Kamath; Zhao, Jingbo; Carpenter, Joshua H; Yan, Hongping; Ade, Harald; Yan, He; Müllen, Klaus; Blom, Paul W M; Pisula, Wojciech; de Leeuw, Dago M; Asadi, Kamal

2018-01-31

It is still a great challenge to fabricate conjugated polymer monolayer field-effect transistors (PoM-FETs) due to intricate crystallization and film formation of conjugated polymers. Here we demonstrate PoM-FETs based on a single monolayer of a conjugated polymer. The resulting PoM-FETs are highly reproducible and exhibit charge carrier mobilities reaching 3 cm 2  V -1  s -1 . The high performance is attributed to the strong interactions of the polymer chains present already in solution leading to pronounced edge-on packing and well-defined microstructure in the monolayer. The high reproducibility enables the integration of discrete unipolar PoM-FETs into inverters and ring oscillators. Real logic functionality has been demonstrated by constructing a 15-bit code generator in which hundreds of self-assembled PoM-FETs are addressed simultaneously. Our results provide the state-of-the-art example of integrated circuits based on a conjugated polymer monolayer, opening prospective pathways for bottom-up organic electronics.

The behaviour of radionuclides in soil

International Nuclear Information System (INIS)

Bunzl, K.

1987-01-01

Radionuclides in soil are of natural as well as of artificial origin. Their migration in the soil and their availability for ecological processes depend considerably on the extent at which they are sorbed. The methods for the determination of the vertical rate of migration are described. For most radionuclides this transport is very slow (a few cm per year). Cs-137 is of especial interest. It is sorbed strongly by most soils and, as a consequence, its root uptake is small. However, as a result of the sorption, this radionuclide is eluted from the root zone only very slowly and its thus available for the root uptake for many years. The Cs-137 concentrations in plants to be expected in the coming years as a result of the fallout from Chernobyl are small. (orig.) [de

Transport of radionuclides in the biosphere

International Nuclear Information System (INIS)

Bundi, A.

1983-10-01

The dispersion of radionuclides in the biosphere and their uptake by man via various nutritional pathways is studied using a compartment model. The sample environment is the area of the lower Limmat and Aare valleys. General considerations of the compartmental description of the biosphere are made. The problem of the description of surface features, in particular soil, sediment and water, is studied in detail using the code BIOPATH. This study is intended to be an example of how a model of the biosphere could be constructed. It is shown that this is a reasonable model to calculate the spreading of radionuclides in the biosphere and that it indicates the relative significance of individual compartments, pathways and radionuclides. Calculated values of dose committment, however, should not be used as reference data for safety analyses. (Auth.)

Bone stress: a radionuclide imaging perspective

International Nuclear Information System (INIS)

Roub, L.W.; Gumerman, L.W.; Hanley, E.N. Jr.; Clark, M.W.; Goodman, M.; Herbert, D.L.

1979-01-01

Thirty-five college athletes with lower leg pain underwent radiography and radionuclide studies to rule out a stress fracture. Their asymptomatic extremities and 13 pain-free athletes served as controls. Four main patterns were observed: (a) sharply marginated scintigraphic abnormalities and positive radiographs; (b) sharply marginated scintigraphic abnormalities and negatives radiographs; (c) ill-defined scintigraphic abnormalities and negative radiographs; and (d) negative radionuclide images and negative radiographs. Since the patients with the first two patterns were otherwise identical medically, the authors feel that this scintigraphic appearance is characterisic of bone stress in the appropriate clinical setting, regardless of the radiographic findings. A schema is proposed to explain the occurrence of positive radionuclide images and negative radiographs in the same patient, using a broad conceptual approach to the problem of bone stress

In vivo evaluation of an anti-PSMA antibody conjugated with varying numbers of biotin molecules in a pretargeting protocol

International Nuclear Information System (INIS)

Wilbur, D.S.; Hamlin, D.K.; Quinn, J.; Vessella, R.L.

2003-01-01

An investigation has been conducted to determine the effect of varying the number of biotin molecules conjugated with an anti-PSMA antibody (mAb) as part of our studies to optimize biotinylated antibodies and radiolabeled streptavidin in pretargeting protocols for Targeted Radionuclide Therapy of prostate cancer. In the investigation, the anti-PSMA antibody 107-1A4 was biotinylated with varying amounts of biotinamidocaproate N-hydroxysuccinimide ester. This procedure resulted in obtaining 107-1A4 with 2.3, 4.5, and 6.8 biotin conjugated as measured by the standard HABA assay. The biotinylated 107-1A4 was radioiodinated and was evaluated in a pretargeting protocol in athymic mice bearing LNCaP human tumor xenografts. In the protocol, 50 μg biotinylated [ 125 I]107-1A4 was injected, followed 48h later by 25 μg of avidin for blood clearance, and 1h after that 20 μg of radiolabeled succinylated recombinant streptavidin ([ 13 1I]sSAv) was administered. The tumor localization and tissue distribution was evaluated at 24, 48, and 72h post [ 131 I]sSAv injection. With 2.3 biotin/mAb, an approximate 1:1 molar ratio (4-5 pmol/g) of sSAv/mAb was obtained at all three time points. With 4.5 biotin/mAb, a 1:1 ratio was observed at 24h, but approx. 2: 1 was observed at 48 and 72h pi. With 6.8 biotin/mAb, sSAv/mAb ratios of approximately 1.5:1; 2:1; and 3:1 were obtained at 24, 48, and 72h pi respectively. The amount of sSAv localized in the tumor was nearly the same (4-5 pmol/g) when 107-1A4 had 2.3 or 4.5 biotin conjugated, but decreased to 3-4.5 pmol/g with 6.8 biotin conjugated. Because the highest levels of co-localized sSAv was found with the lowest number of biotin conjugates, the observed differences in ratios of sSAv/mAb may be best explained as differences in internalization, and degradation of mAb and protease resistant sSAv. In duplicate experiments, similar results were obtained with biotinylated 107-1A4 F(ab') 2 , but not with an mAb to a non-internalizing antigen

Radionuclide migration in groundwater. Annual progress report for 1982

International Nuclear Information System (INIS)

Robertson, D.E.; Toste, A.P.; Abel, K.H.; Brodzinski, R.L.

1984-01-01

Research has continued at a low-level waste disposal facility to characterize the physicochemical species of radionuclides migrating in groundwater. This facility consists of an unlined basin and connecting trench which receives effluent water containing low levels of a wide variety of fission and activation products and trace amounts of transuranic radionuclides. The effluent water percolates through the soil and a small fraction of it emerges at seepage springs located some 260 meters from the trench. The disposal basin and trench are very efficient in retaining most of the radionuclides, but trace amounts of a number of radionuclides existing in mobile chemical forms migrate in the groundwater from the trench to the springs. This facility provides the opportunity for characterizing the rates and mechanisms of radionuclide migration in groundwaters, identifying retardation processes, and validating geochemical models. 13 references, 25 figures, 23 tables

METHOD OF CONJUGATED CIRCULAR ARCS TRACING

Directory of Open Access Journals (Sweden)

N. Ageyev Vladimir

2017-01-01

Full Text Available The geometric properties of conjugated circular arcs connecting two points on the plane with set directions of tan- gent vectors are studied in the work. It is shown that pairs of conjugated circular arcs with the same conditions in frontier points create one-parameter set of smooth curves tightly filling all the plane. One of the basic properties of this set is the fact that all coupling points of circular arcs are on the circular curve going through the initially given points. The circle radius depends on the direction of tangent vectors. Any point of the circle curve, named auxiliary in this work, determines a pair of conjugated arcs with given boundary conditions. One more condition of the auxiliary circle curve is that it divides the plane into two parts. The arcs going from the initial point are out of the circle limited by this circle curve and the arcs coming to the final point are inside it. These properties are the basis for the method of conjugated circular arcs tracing pro- posed in this article. The algorithm is rather simple and allows to fulfill all the needed plottings using only the divider and ruler. Two concrete examples are considered. The first one is related to the problem of tracing of a pair of conjugated arcs with the minimal curve jump when going through the coupling point. The second one demonstrates the possibility of trac- ing of the smooth curve going through any three points on the plane under condition that in the initial and final points the directions of tangent vectors are given. The proposed methods of conjugated circular arcs tracing can be applied in solving of a wide variety of problems connected with the tracing of cam contours, for example pattern curves in textile industry or in computer-aided-design systems when programming of looms with numeric control.

Modeling delay in genetic networks: from delay birth-death processes to delay stochastic differential equations.

Science.gov (United States)

Gupta, Chinmaya; López, José Manuel; Azencott, Robert; Bennett, Matthew R; Josić, Krešimir; Ott, William

2014-05-28

Delay is an important and ubiquitous aspect of many biochemical processes. For example, delay plays a central role in the dynamics of genetic regulatory networks as it stems from the sequential assembly of first mRNA and then protein. Genetic regulatory networks are therefore frequently modeled as stochastic birth-death processes with delay. Here, we examine the relationship between delay birth-death processes and their appropriate approximating delay chemical Langevin equations. We prove a quantitative bound on the error between the pathwise realizations of these two processes. Our results hold for both fixed delay and distributed delay. Simulations demonstrate that the delay chemical Langevin approximation is accurate even at moderate system sizes. It captures dynamical features such as the oscillatory behavior in negative feedback circuits, cross-correlations between nodes in a network, and spatial and temporal information in two commonly studied motifs of metastability in biochemical systems. Overall, these results provide a foundation for using delay stochastic differential equations to approximate the dynamics of birth-death processes with delay.

Modeling delay in genetic networks: From delay birth-death processes to delay stochastic differential equations

Energy Technology Data Exchange (ETDEWEB)

Gupta, Chinmaya; López, José Manuel; Azencott, Robert; Ott, William [Department of Mathematics, University of Houston, Houston, Texas 77004 (United States); Bennett, Matthew R. [Department of Biochemistry and Cell Biology, Rice University, Houston, Texas 77204, USA and Institute of Biosciences and Bioengineering, Rice University, Houston, Texas 77005 (United States); Josić, Krešimir [Department of Mathematics, University of Houston, Houston, Texas 77004 (United States); Department of Biology and Biochemistry, University of Houston, Houston, Texas 77204 (United States)

2014-05-28

Delay is an important and ubiquitous aspect of many biochemical processes. For example, delay plays a central role in the dynamics of genetic regulatory networks as it stems from the sequential assembly of first mRNA and then protein. Genetic regulatory networks are therefore frequently modeled as stochastic birth-death processes with delay. Here, we examine the relationship between delay birth-death processes and their appropriate approximating delay chemical Langevin equations. We prove a quantitative bound on the error between the pathwise realizations of these two processes. Our results hold for both fixed delay and distributed delay. Simulations demonstrate that the delay chemical Langevin approximation is accurate even at moderate system sizes. It captures dynamical features such as the oscillatory behavior in negative feedback circuits, cross-correlations between nodes in a network, and spatial and temporal information in two commonly studied motifs of metastability in biochemical systems. Overall, these results provide a foundation for using delay stochastic differential equations to approximate the dynamics of birth-death processes with delay.

Modeling delay in genetic networks: From delay birth-death processes to delay stochastic differential equations

International Nuclear Information System (INIS)

Gupta, Chinmaya; López, José Manuel; Azencott, Robert; Ott, William; Bennett, Matthew R.; Josić, Krešimir

2014-01-01

Delay is an important and ubiquitous aspect of many biochemical processes. For example, delay plays a central role in the dynamics of genetic regulatory networks as it stems from the sequential assembly of first mRNA and then protein. Genetic regulatory networks are therefore frequently modeled as stochastic birth-death processes with delay. Here, we examine the relationship between delay birth-death processes and their appropriate approximating delay chemical Langevin equations. We prove a quantitative bound on the error between the pathwise realizations of these two processes. Our results hold for both fixed delay and distributed delay. Simulations demonstrate that the delay chemical Langevin approximation is accurate even at moderate system sizes. It captures dynamical features such as the oscillatory behavior in negative feedback circuits, cross-correlations between nodes in a network, and spatial and temporal information in two commonly studied motifs of metastability in biochemical systems. Overall, these results provide a foundation for using delay stochastic differential equations to approximate the dynamics of birth-death processes with delay

Field surveying of radionuclide contamination in forests

International Nuclear Information System (INIS)

Turunen, J.; Rantavaara, A.; Ammann, M.

2009-01-01

Field measurements of radionuclides after an accidental contamination of forests assume the capacity for identification of a number of nuclides in varying source geometries. The continuous redistribution of radionuclides in forests through natural processes implies a decrease of prevailing surface contamination of trees and an increase in activity density on the ground. Portable gamma spectrometers have long been based on Na(I) detectors which, due to their low energy resolution, are not the tool for analysis of contamination from accidental releases of fission and activation products in the first days or weeks after a deposition. Data of airborne radionuclides from the Chernobyl accident in April 1986 were used for demonstration of initial and later distribution of radionuclides as sources of air Kerma in forests. Forest model (FDMF, PV. 6.0) of the RODOS system was used for the assessment of time-dependent Kerma rate from different forest compartments. The results show the fast reduction of activities of short-lived nuclides and their contributions to the Kerma rate in the first weeks and months. The results also give an estimate for the time needed until a gamma spectrometer with a low energy resolution would give useful information about long-lived radioactivity on the forest floor. An example is given on a portable high resolution semiconductor spectrometer that has suitable characteristics for field surveying also during occurrence of a great number of radionuclides contributing to the gamma spectrum. The needs for further research of a recently deposited radionuclide contamination on forest vegetation and soil, and the efforts for improvement of portable radiation meters and their use in management planning and radioecological research on contaminated forests are discussed. (au)

Exchange of certain radionuclides between environment and freshwater algae

International Nuclear Information System (INIS)

Marchyulenene, E. D.P.

1978-01-01

Data on the dynamics and levels of accumulation of strontium, cesium, cerium and ruthenium radionuclides by Charophyta and Cladophora fresh-water algae are presented. An attempt has been made to investigate some processes that accompany the accumulation of radionuclides by plants. Under experimental conditions, the intensity and levels of radionuclide accumulation can be presented in the following order: 144 Ce> 106 Ru> 90 Sr> 137 Cs. The dynamics of radionuclide accumulation varied greatly with the radionuclide and the algae species studied. The 144 Ce accumulation coefficients (AC) in the course of experiment (from 3 hours to 16 days) increased 8-, 9-, 23.4-, 27-, 14.3- and 20.4-fold for Cladophora glomerata, Nitella syncarpa, Nitellopsis obtusa, Chara vulgaris, Ch. rudis, and Ch. aspera, respectively. In the case of 106 Ru, AC for C.glomerata, N. syncarapa, Ch. vulgaris and Ch. rudis increased 34-, 18-,24- and 23-fold, respectively. In all algae species studied the equilibrium of radionuclide accumulation was attained after 2-4 days of experiment. Levels of accumulated 90 Sr and 137 Cs in most species depended on the season while that of 144 Cs and 106 Ru remained constant throughout the vegetation period. The levels of radionuclide elimination, like the accumulation levels, are shown to depend on both isotopes and algae species

Peptide-Carrier Conjugation

DEFF Research Database (Denmark)

Hansen, Paul Robert

2015-01-01

To produce antibodies against synthetic peptides it is necessary to couple them to a protein carrier. This chapter provides a nonspecialist overview of peptide-carrier conjugation. Furthermore, a protocol for coupling cysteine-containing peptides to bovine serum albumin is outlined....

Exposure to radionuclides in smoke from vegetation fires

International Nuclear Information System (INIS)

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

2014-01-01

Naturally occurring radionuclides of uranium, thorium, radium, lead and polonium were determined in bushes and trees and in the smoke from summer forest fires. Activity concentrations of radionuclides in smoke particles were much enriched when compared to original vegetation. Polonium-210 ( 210 Po) in smoke was measured in concentrations much higher than all other radionuclides, reaching 7255 ± 285 Bq kg −1 , mostly associated with the smaller size smoke particles ( 210 Po in surface air near forest fires displayed volume concentrations up to 70 mBq m −3 , while in smoke-free air 210 Po concentration was about 30 μBq m −3 . The estimated absorbed radiation dose to an adult member of the public or a firefighter exposed for 24 h to inhalation of smoke near forest fires could exceed 5 μSv per day, i.e, more than 2000 times above the radiation dose from background radioactivity in surface air, and also higher than the radiation dose from 210 Po inhalation in a chronic cigarette smoker. It is concluded that prolonged exposure to smoke allows for enhanced inhalation of radionuclides associated with smoke particles. Due to high radiotoxicity of alpha emitting radionuclides, and in particular of 210 Po, the protection of respiratory tract of fire fighters is strongly recommended. - Highlights: • Natural radionuclides in vegetation are in low concentrations. • Forest fires release natural radionuclides from vegetation and concentrate them in inhalable ash particles. • Prolonged inhalation of smoke from forest fires gives rise enhanced radiation exposure of lungs especially due to polonium. • Respiratory protection of fire fighters and members of public is highly recommended for radioprotection reasons

Consequence ranking of radionuclides in Hanford tank waste

International Nuclear Information System (INIS)

Schmittroth, F.A.; De Lorenzo, T.H.

1995-09-01

Radionuclides in the Hanford tank waste are ranked relative to their consequences for the Low-Level Tank Waste program. The ranking identifies key radionuclides where further study is merited. In addition to potential consequences for intrude and drinking-water scenarios supporting low-level waste activities, a ranking based on shielding criteria is provided. The radionuclide production inventories are based on a new and independent ORIGEN2 calculation representing the operation of all Hanford single-pass reactors and the N Reactor

Class, Kinship Density, and Conjugal Role Segregation.

Science.gov (United States)

Hill, Malcolm D.

1988-01-01

Studied conjugal role segregation in 150 married women from intact families in working-class community. Found that, although involvement in dense kinship networks was associated with conjugal role segregation, respondents' attitudes toward marital roles and phase of family cycle when young children were present were more powerful predictors of…

Colloid-facilitated radionuclide transport: a regulatory perspective

Science.gov (United States)

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

2001-12-01

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

Solar multi-conjugate adaptive optics performance improvement

Science.gov (United States)

Zhang, Zhicheng; Zhang, Xiaofang; Song, Jie

2015-08-01

In order to overcome the effect of the atmospheric anisoplanatism, Multi-Conjugate Adaptive Optics (MCAO), which was developed based on turbulence correction by means of several deformable mirrors (DMs) conjugated to different altitude and by which the limit of a small corrected FOV that is achievable with AO is overcome and a wider FOV is able to be corrected, has been widely used to widen the field-of-view (FOV) of a solar telescope. With the assistance of the multi-threaded Adaptive Optics Simulator (MAOS), we can make a 3D reconstruction of the distorted wavefront. The correction is applied by one or more DMs. This technique benefits from information about atmospheric turbulence at different layers, which can be used to reconstruct the wavefront extremely well. In MAOS, the sensors are either simulated as idealized wavefront gradient sensors, tip-tilt sensors based on the best Zernike fit, or a WFS using physical optics and incorporating user specified pixel characteristics and a matched filter pixel processing algorithm. Only considering the atmospheric anisoplanatism, we focus on how the performance of a solar MCAO system is related to the numbers of DMs and their conjugate heights. We theoretically quantify the performance of the tomographic solar MCAO system. The results indicate that the tomographic AO system can improve the average Strehl ratio of a solar telescope by only employing one or two DMs conjugated to the optimum altitude. And the S.R. has a significant increase when more deformable mirrors are used. Furthermore, we discuss the effects of DM conjugate altitude on the correction achievable by the MCAO system, and present the optimum DM conjugate altitudes.

The uptake of radionuclides by plants

International Nuclear Information System (INIS)

Cawse, P.A.; Turner, G.S.

1982-02-01

A review of the literature, since 1970, on the research into the uptake of radionuclides by plants, with references to earlier soil and plant studies on the fate of nuclear weapons fallout. Experimental data on the uptake of plutonium isotopes, americium 241, cesium 137, radium 226, curium 244 and neptunium 237 and details of the chemical form of the radionuclide, soil type and plant growth period are tabulated. (U.K.)

Report on the intercomparison run IAEA-156 radionuclides in clover

International Nuclear Information System (INIS)

Strachnov, V.; Valkovic, V.; Dekner, R.

1991-01-01

This report contains the results of the intercomparison IAEA-156 on the determination of radionuclides in clover. Initially participants were requested to determine the levels of 134 Cs, 137 Cs, 40 K, 90 Sr and invited to provide data for other radionuclides. The participants included 46 laboratories located in 25 countries, and statistical evaluation of their data yield recommended values for these four radionuclides. Additional radionuclides reported were 210 Pb, 239 Pu and 125 Sb; however, insufficient data exists to statistically determine recommended values for these radionuclides. The following are the recommended values, with confidence intervals, for the most frequently measured radionuclides (reference date: 1 August 1986): 134 Cs 132.1 Bq/kg (126.4-137.7); 137 Cs 264 Bq/kg (254-274); 40 K 657 Bq/kg (637-676); 90 Sr 14.8 Bq/kg (13.4-16.3). Figs and tabs

Criteria of reference radionuclides for safety analysis of spent fuel waste disposal

International Nuclear Information System (INIS)

Suryanto

1998-01-01

Study on the criteria for reference radionuclides selection for assessment on spent fuel disposal have done. The reference radionuclides in this study means radionuclides are predicted to contribute of the most radiological effect for man if spent fuel waste are discharged on deep geology formation. The research was done by investigate critically of parameters were used on evaluation a kind of radionuclide. Especially, this research study of parameter which relevant disposal case and or spent fuel waste on deep geology formation . The research assumed that spent fuel discharged on deep geology by depth 500-1000 meters from surface of the land. The migration scenario Radionuclides from waste form to man was assumed particularly for normal release in which Radionuclides discharge from waste form in a series thorough container, buffer, geological, rock, to fracture(fault) and move together with ground water go to biosphere and than go into human body. On this scenario, the parameter such as radionuclides inventory, half life, heat generation, hazard index based on maximum permissible concentration (MPC) or annual limit on intake (ALI) was developed as criteria of reference radionuclides selection. The research concluded that radionuclides inventory, half live, heat generated, hazard index base on MPC or ALI can be used as criteria for selection of reference Radionuclide. The research obtained that the main radionuclides are predicted give the most radiological effect to human are as Cs-137, Sr-90, I-129, Am-243, Cm-244, Pu-238, Pu-239, Pu-240. The radionuclides reasonable to be used as reference radionuclides in safety analysis at spent fuel disposal. (author)

Radionuclides in marine organisms

International Nuclear Information System (INIS)

Honda, Teruyuki

2001-01-01

The concentration and accumulation of radionuclides in marine organisms were explained in this paper. Secular change of the radioactivity concentration of 137 Cs in seaweed in coastal area of Japan showed more than 5Bq/kg-fresh in the first half of 1960, but decreased less than 1 Bq/kg-fresh after then and attained to less than 0.1 Bq/kg-fresh in 1990s. However, the value increased a while in 1986, which indicated the effect of Chernobyl accident. The accident increased 137 Cs of shellfish near Japan. The concentration of 239+240 Pu was the lowest value in muscles of fish, but increased from 1.7 to 42.3 mBq/kg wet wt in seaweed in 1999. 99 Tc concentration of seaweed showed from 100 to 1000 times as much as that of seawater. Radionuclides in the Irish Sea are originated from Sellafield reprocessing plant. The concentration factors of macro-algae and surface water fish (IAEA,1985) were shown. Analytical results of U in 61 kinds of marine organs showed that the concentration was different in the part of organ. The higher concentration of U was observed in hard tissue of fish. The concentration factor was different between chemical substances with the same radionuclides. (S.Y.)

Development of radionuclide parameter database on internal contamination in nuclear emergencies

International Nuclear Information System (INIS)

Zhao Li; Xu Cuihua; Li Wenhong; Su Xu

2010-01-01

Objective: To develop a radionuclide parameter database on internal contamination in nuclear emergencies. Methods: By researching the radionuclides composition discharged from different nuclear emergencies, the radionuclide parameters were achieved on physical decay, absorption and metabolism in the body from ICRP publications and some other publications. The database on internal contamination for nuclear incidents was developed by using MS Visual Studio 2005 C and MS Access programming language. Results: The radionuclide parameter database on internal contamination in nuclear emergency was established. Conclusions: The database may be very convenient for searching radionuclides and radionuclide parameter data discharged from different nuclear emergencies, which would be helpful to the monitoring and assessment and assessment of internal contamination in nuclear emergencies. (authors)

Report on the intercomparison run IAEA-321 radionuclides in milk powder

International Nuclear Information System (INIS)

Strachnov, V.; Burns, K.; Dekner, R.

1990-01-01

This report contains the results of the intercomparison IAEA-321 on the determination of radionuclides in milk powder. Initially participants were requested to determine the levels of 134 Cs, 137 Cs, 40 K, 90 Sr and invited to provide data for other radionuclides. The participants included 61 laboratories located in 29 countries, and statistical evaluation of their data yield recommended values for these four radionuclides. Additional radionuclides reported were 226 Ra and 232 Th, however insufficient data exists to statistically determine recommended values for these radionuclides. The recommended values for radionuclide determination are: 134 Cs: 15.5 Bq/kg; 137 Cs: 72.6 Bq/Kg; 40 K: 552 Bq/kg; 90 Sr: 3.3 Bq/kg. Tabs

New best estimates for radionuclide solid-liquid distribution coefficients in soils. Part 3: miscellany of radionuclides (Cd, Co, Ni, Zn, I, Se, Sb, Pu, Am, and others)

International Nuclear Information System (INIS)

Gil-Garcia, C.; Tagami, K.; Uchida, S.; Rigol, A.; Vidal, M.

2009-01-01

New best estimates for the solid-liquid distribution coefficient (K d ) for a set of radionuclides are proposed, based on a selective data search and subsequent calculation of geometric means. The K d best estimates are calculated for soils grouped according to the texture and organic matter content. For a limited number of radionuclides this is extended to consider soil cofactors affecting soil-radionuclide interaction, such as pH, organic matter content, and radionuclide chemical speciation. Correlations between main soil properties and radionuclide K d are examined to complete the information derived from the best estimates with a rough prediction of K d based on soil parameters. Although there are still gaps for many radionuclides, new data from recent studies improve the calculation of K d best estimates for a number of radionuclides, such as selenium, antimony, and iodine.

A random walk model to simulate the atmospheric dispersion of radionuclide

Science.gov (United States)

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

2018-01-01

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

Correlation Water Velocity and TSS with Natural Radionuclides Activity

International Nuclear Information System (INIS)

Tri Harningsih; Muzakky; Agus Taftazani

2007-01-01

Correlation water velocity and TSS with natural radionuclides activity has been studied. For that purpose, the study is to correlation water velocity and TSS with radionuclides on water and sediment samples in alongside river Code Yogyakarta. This research selected radionuclides, for examples Ra-226, Pb-212, Ac- 228, and K-40. Election of this radionuclides to spread over gamma gross composition alongside river of Code. Gamma gross influenced by water velocity and TSS, so that require to correct between water velocity and TSS to radionuclides. Sampling water and sediment conducted when dry season of August, 2006 at 11 locations, start from Boyong Bridge until Pacar Bridge. Result of analysis showed that water velocity range from 8-1070 L/dt and TSS range from 2.81 E-06 - 8.02 E-04 mg/L. The accumulation of radionuclides in water samples non correction water velocity for Ra-226: 0.302-2.861 Bq/L, Pb-212: 0.400-3.390 Bq/L, Ac- 228: 0.0029-0.0047 Bq/L and K-40: 0.780-9.178 Bq/L. The accumulation of radionuclide in water samples correction water velocity for Ra-226: 1.112-70.454 Bq/L, Pb-212: 0.850-77.113 Bq/L, Ac-228: 0.7187- 60.859 Bq/L and K-40: 2.420-208.8 Bq/L. While distribution of radionuclide in sediment for the Ra-226: 0.0012-0.0211 Bq/kg, Pb-212: 0.0017-0.0371 Bq/kg, Ac-228: 0.0021-0.0073 Bq/kg and K-40: 0.0006-0.0084 Bq/kg. (author)

Removal of radionuclides from liquid streams by reverse osmosis

International Nuclear Information System (INIS)

Deshmukh, U.A.; Ramachandhran, V.; Misra, B.M.

1987-01-01

Separation of radionuclides in trace concentrations by cellulose acetate membranes has been under investigation in this laboratory, and the behaviour of some important radionuclides such as 137 Cs and 90 Sr under reverse osmosis has been reported earlier. The present work deals with a few other typical radionuclides such as 60 Co, 103 Ru and 131 I which are not fully amenable to conventional methods for their removal. Separation of these radionuclides from liquid streams by the reverse osmosis process was studied using a small reverse osmosis test cell. Various parameters like membrane porosity, applied pressure and feed activity levels were investigated. Cellulose acetate membranes offer reasonable separation of 60 Co, 103 Ru and 131 I radionuclides, indicating the potential of reverse osmosis for treatment of effluents containing these radioisotopes. The percent separation is found to be in the order of Co > Ru > I. The percent radioactive separation improves with increases in feed activity. The performance data are explained in terms of solution-diffusion mechanism. It appears that the separation of radionuclides is not governed by diffusion alone, but by the interaction of solutes with the membranes. (author)

Site-Selective Conjugation of Native Proteins with DNA

DEFF Research Database (Denmark)

Trads, Julie Brender; Tørring, Thomas; Gothelf, Kurt Vesterager

2017-01-01

Conjugation of DNA to proteins is increasingly used in academia and industry to provide proteins with tags for identification or handles for hybridization to other DNA strands. Assay technologies such as immuno-PCR and proximity ligation and the imaging technology DNA-PAINT require DNA-protein....... The introduction of a bioorthogonal handle at a specific position of a protein by recombinant techniques provides an excellent approach to site-specific conjugation, but for many laboratories and for applications where several proteins are to be labeled, the expression of recombinant proteins may be cumbersome...... conjugates. In DNA nanotechnology, the DNA handle is exploited to precisely position proteins by self-assembly. For these applications, site-selective conjugation is almost always desired because fully functional proteins are required to maintain the specificity of antibodies and the activity of enzymes...

Conjugated Polymers for Flexible Energy Harvesting and Storage.

Science.gov (United States)

Zhang, Zhitao; Liao, Meng; Lou, Huiqing; Hu, Yajie; Sun, Xuemei; Peng, Huisheng

2018-03-01

Since the discovery of conjugated polymers in the 1970s, they have attracted considerable interest in light of their advantages of having a tunable bandgap, high electroactivity, high flexibility, and good processability compared to inorganic conducting materials. The above combined advantages make them promising for effective energy harvesting and storage, which have been widely studied in recent decades. Herein, the key advancements in the use of conjugated polymers for flexible energy harvesting and storage are reviewed. The synthesis, structure, and properties of conjugated polymers are first summarized. Then, their applications in flexible polymer solar cells, thermoelectric generators, supercapacitors, and lithium-ion batteries are described. The remaining challenges are then discussed to highlight the future direction in the development of conjugated polymers. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Formation of primary sperm conjugates in a haplogyne spider (Caponiidae, Araneae) with remarks on the evolution of sperm conjugation in spiders.

Science.gov (United States)

Lipke, Elisabeth; Michalik, Peter

2012-11-01

Sperm conjugation, where two or more sperm are physically united, is a rare but widespread pheno-menon across the animal kingdom. One group well known for its different types of sperm conjugation are spiders. Particularly, haplogyne spiders show a high diversity of sperm traits. Besides individual cleistospermia, primary (synspermia) and secondary (coenospermia, "spermatophore") sperm conjugation occurs. However, the evolution of sperm conjugates and sperm is not understood in this group. Here, we look at how sperm are transferred in Caponiidae (Haplogynae) in pursuit of additional information about the evolution of sperm transfer forms in spiders. Additionally, we investigated the male reproductive system and spermatozoa using light- and transmission electron-microscopy and provide a 3D reconstruction of individual as of well as conjugated spermatozoa. Mature spermatozoa are characterized by an extremely elongated, helical nucleus resulting in the longest spider sperm known to date. At the end of spermiogenesis, synspermia are formed by complete fusion of four spermatids. Thus, synspermia might have evolved early within ecribellate Haplogynae. The fused sperm cells are surrounded by a prominent vesicular area. The function of the vesicular area remains still unknown but might be correlated with the capacitation process inside the female. Further phylogenetic and functional implications of the spermatozoa and sperm conjugation are discussed. Copyright © 2012 Elsevier Ltd. All rights reserved.

Design and biological activity of β-sheet breaker peptide conjugates

International Nuclear Information System (INIS)

Rocha, Sandra; Cardoso, Isabel; Boerner, Hans; Pereira, Maria Carmo; Saraiva, Maria Joao; Coelho, Manuel

2009-01-01

The sequence LPFFD (iAβ 5 ) prevents amyloid-β peptide (Aβ) fibrillogenesis and neurotoxicity, hallmarks of Alzheimer's disease (AD), as previously demonstrated. In this study iAβ 5 was covalently linked to poly(ethylene glycol) (PEG) and the activity of conjugates was assessed and compared to the activity of the peptide alone by in vitro studies. The conjugates were characterized by MALDI-TOF. Competition binding assays established that conjugates retained the ability to bind Aβ with similar strength as iAβ 5 . Transmission electron microscopy analysis showed that iAβ 5 conjugates inhibited amyloid fibril formation, which is in agreement with binding properties observed for the conjugates towards Aβ. The conjugates were also able to prevent amyloid-induced cell death, as evaluated by activation of caspase 3. These results demonstrated that the biological activity of iAβ 5 is not affected by the pegylation process.

Separation of radionuclides from water by magnesium oxide adsorption

International Nuclear Information System (INIS)

Tseng, Chia-Lian; Lo, Jem-Mau; Yeh, Si-Jung

1987-01-01

Adsorption by magnesium oxide of more than forty radionuclides in respective ionic species in water was observed. Generally, the radionuclides in di-valent and/or multi-valent cations are favorably adsorbed by magnesium oxide; but not for the those in mono-valent cations. In addition, the adsorption by magnesium oxide was not effective to most of the radionuclides in negative ionic species. From the observations, the adsorption mechanism is more prominently by the ion exchange of the di- or multi-valent cation species with the hydrous magnesium oxide. Separation of the radionuclides related to the corrosion products possibly produced in a nuclear power plant from natural seawater was attempted by the magnesium oxide adsorption method. It should be emphasized that the adsorption method was found to be practical for separating radionuclides from a large quantity of natural seawater with high recovery and high reproducibility. (author)

Mechanisms of radionuclide transition in natural environment

International Nuclear Information System (INIS)

Pacyna, J.

1974-01-01

Mechanisms of radionuclide transition in various elements of the environment have been dealt with in an ecological aspect. The knowledge of the radionuclide propagation tracks will make possible to ascertain precisely causes and effects of the radiation and to reduce the contamination value. Particular attention has been paid to test methods. (author)

Building shielding effects on radiation doses from routine radionuclide releases

International Nuclear Information System (INIS)

Kocher, D.C.

1977-01-01

In calculating population doses from the release of radionuclides to the atmosphere, it is usually assumed that man spends all of his time outdoors standing on a smooth infinite plane. Realistically, however, man spends most of the time indoors, so that substantial reductions in radiation doses may result compared with the usual estimates. Calculational models were developed to study the effects of building structures on radiation doses from routine releases of radionuclides to the atmosphere. Both internal dose from inhaled radionuclides and external photon dose from airborne and surface-deposited radionuclides are considered. The effect of building structures is described quantitatively by a dose reduction factor, which is the ratio of the dose inside a structure to the corresponding dose with no structure present. The internal dose from inhaled radionuclides is proportional to the radionuclide concentration in the air. Assuming that the outdoor airborne concentration is constant with time, the time-dependence of the indoor airborne concentration in terms of the structure air ventilation rate, the deposition velocities for radionuclides on the inside floor, walls, and ceiling, and the radioactive decay constant, were calculated

Trends in cyclotrons for radionuclide production

International Nuclear Information System (INIS)

Vera Ruiz, H.; Lambrecht, R.M.

1999-01-01

The IAEA recently concluded a worldwide survey of the cyclotrons used for radionuclide production. Most of the institutions responded to the questionnaire. The responses identified technical, utilisation and administrative information for 206 cyclotrons. Compiled data includes the characteristics, performance and popularity of each of the different commercial cyclotrons. Over 20 cyclotrons are scheduled for installation in 1998. The expansion in the number of cyclotron installations during the last decade was driven by the advent of advances in medical imaging instrumentation (namely, positron emission tomography (PET), and more recently by 511 KeV emission tomography); introduction of user friendly compact medical cyclotrons; and recent governmental decisions that permit reimbursement for cyclotron radiopharmaceutical studies by the government or insurance companies. The priorities for the production of clinical, commercial and research radionuclides were identified. The emphasis is on radionuclides used for medical diagnosis with SPET (e.g. 123 I, 201 Tl) and PET (e.g. 11 C, 13 N, 15 O, 18 F) radiopharmaceuticals, and for individualized patient radiation treatment planning (e.g. 64 Cu, 86 Y, 124 I) with PET. There is an emerging trend to advance the cyclotron as an alternative method to nuclear reactors for the production of neutron-rich radionuclides (e.g. 64 Cu, 103 Pd, 186 Re) needed for therapeutic applications. (authors)

The extended regulatory networks of SXT/R391 integrative and conjugative elements and IncA/C conjugative plasmids.

Science.gov (United States)

Poulin-Laprade, Dominic; Carraro, Nicolas; Burrus, Vincent

2015-01-01

Nowadays, healthcare systems are challenged by a major worldwide drug resistance crisis caused by the massive and rapid dissemination of antibiotic resistance genes and associated emergence of multidrug resistant pathogenic bacteria, in both clinical and environmental settings. Conjugation is the main driving force of gene transfer among microorganisms. This mechanism of horizontal gene transfer mediates the translocation of large DNA fragments between two bacterial cells in direct contact. Integrative and conjugative elements (ICEs) of the SXT/R391 family (SRIs) and IncA/C conjugative plasmids (ACPs) are responsible for the dissemination of a broad spectrum of antibiotic resistance genes among diverse species of Enterobacteriaceae and Vibrionaceae. The biology, diversity, prevalence and distribution of these two families of conjugative elements have been the subject of extensive studies for the past 15 years. Recently, the transcriptional regulators that govern their dissemination through the expression of ICE- or plasmid-encoded transfer genes have been described. Unrelated repressors control the activation of conjugation by preventing the expression of two related master activator complexes in both types of elements, i.e., SetCD in SXT/R391 ICEs and AcaCD in IncA/C plasmids. Finally, in addition to activating ICE- or plasmid-borne genes, these master activators have been shown to specifically activate phylogenetically unrelated mobilizable genomic islands (MGIs) that also disseminate antibiotic resistance genes and other adaptive traits among a plethora of pathogens such as Vibrio cholerae and Salmonella enterica.

The extended regulatory networks of SXT/R391 integrative and conjugative elements and IncA/C conjugative plasmids.

Directory of Open Access Journals (Sweden)

Dominic ePoulin-Laprade

2015-08-01

Full Text Available Nowadays, healthcare systems are challenged by a major worldwide drug resistance crisis caused by the massive and rapid dissemination of antibiotic resistance genes and associated emergence of multidrug resistant pathogenic bacteria, in both clinical and environmental settings. Conjugation is the main driving force of gene transfer among microorganisms. This mechanism of horizontal gene transfer mediates the translocation of large DNA fragments between two bacterial cells in direct contact. Integrative and conjugative elements (ICEs of the SXT/R391 family (SRIs and IncA/C conjugative plasmids (ACPs are responsible for the dissemination of a broad spectrum of antibiotic resistance genes among diverse species of Enterobacteriaceae and Vibrionaceae. The biology, diversity, prevalence and distribution of these two families of conjugative elements have been the subject of extensive studies for the past 15 years. Recently, the transcriptional regulators that govern their dissemination through the expression of ICE- or plasmid-encoded transfer genes have been described. Unrelated repressors control the activation of conjugation by preventing the expression of two related master activator complexes in both types of elements, i.e. SetCD in SXT/R391 ICEs and AcaCD in IncA/C plasmids. Finally, in addition to activating ICE- or plasmid-borne genes, these master activators have been shown to specifically activate phylogenetically unrelated mobilizable genomic islands (MGIs that also disseminate antibiotic resistance genes and other adaptive traits among a plethora of pathogens such as Vibrio cholerae and Salmonella enterica.

Study of monitoring protection of radionuclides contamination in organism by autoradiography

International Nuclear Information System (INIS)

Zhu Shoupeng; Kang Baoan; He Guangren

1987-01-01

In view of the exceptionally important role of the medical radiation protection in human health, the authors try to study on the monitoring of internal contamination of radionuclides in organism by different autoradiographic methods, such as: monitoring of the body retention of isolated or combined radionuclides by freezing microautoradiography; monitoring of blood, bone marrow and excreta radioactive samples by smear autoradiography; differentiation of two radionuclides contamination by double radionuclide autoradiography; especially, monitoring of low level of radionuclides contamination by fluorescence sensitization autoradiography. The sensitivity of autoradiographic formation was increased by the scintillator by 10 times

Database for long lived radionuclides (LLRN). CEA working group report

International Nuclear Information System (INIS)

2003-01-01

This report constitutes a data base for long lived radionuclides (with half lives ranging from 30 to 10 14 years) presenting informations on seven different topics: 'Radioactive data' gathers fundamental data characterising radioactive properties of considered radionuclides (half-life, disintegration mode, radiation energy,...); 'Formation and inventory' collects data on radionuclide formation ways as well as quantities formed during fuel irradiation; 'Biological effects' gives data characterising both radiotoxicity for each radionuclide and chemical toxicity for the considered element; 'Partitioning' specifies element repartition according to the different ways of Purex reprocessing and complementary partitioning processes possible for isolating chemical elements corresponding to the considered radionuclides; 'Transmutation' provides data allowing in part to evaluate the feasibility and destruction performances of radionuclides by transmutation with neutrons; 'Behaviour in waste packages' gathers some data relative to the properties of waste packages confinement. Only data on vitrified waste packages are given there; 'Behaviour in diluted solution' provides data used for element migration calculations. (author)

Natural and anthropogenic radionuclide activity concentrations in the New Zealand diet

International Nuclear Information System (INIS)

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

2016-01-01

To support New Zealand's food safety monitoring regime, a survey was undertaken to establish radionuclide activity concentrations across the New Zealand diet. This survey was undertaken to better understand the radioactivity content of the modern diet and also to assess the suitability of the current use of milk as a sentinel for dietary radionuclide trends. Thirteen radionuclides were analysed in 40 common food commodities, including animal products, fruits, vegetables, cereal grains and seafood. Activity was detected for 137 Caesium, 90 Strontium and 131 Iodine. No other anthropogenic radionuclides were detected. Activity concentrations of the three natural radionuclides of Uranium and the daughter radionuclide 210 Polonium were detected in the majority of food sampled, with a large variation in magnitude. The maximum activity concentrations were detected in shellfish for all these radionuclides. Based on the established activity concentrations and ranges, the New Zealand diet contains activity concentrations of anthropogenic radionuclides far below the Codex Alimentarius guideline levels. Activity concentrations obtained for milk support its continued use as a sentinel for monitoring fallout radionuclides in terrestrial agriculture. The significant levels of natural and anthropogenic radionuclide activity concentrations detected in finfish and molluscs support undertaking further research to identify a suitable sentinel for New Zealand seafood monitoring. - Highlights: • A radionuclide monitoring program was undertaken across the New Zealand food supply. • 40 food types were analysed for 13 radionuclides. • 137 Cs was present in 15% of foods (range: 0.05–0.44Bq/kg). • Anthropogenic radionuclides displayed compliance with international limits. • 210 Po, 234 U and 238 U were present in most foods with large ranges of activities.

Speciation and transport of radionuclides in ground water

International Nuclear Information System (INIS)

Robertson, D.E.; Toste, A.P.; Abel, K.H.; Cowan, C.E.; Jenne, E.A.; Thomas, C.W.

1984-01-01

Studies of the chemical speciation of a number of radionuclides migrating in a slightly contaminated ground water plume are identifying the most mobile species and providing an opportunity to test and/or validate geochemical models of radionuclide transport in ground waters. Results to date have shown that most of the migrating radionuclides are present in anionic or nonionic forms. These include anionic forms of 55 Fe, 60 Co, /sup 99m/Tc, 106 Ru, 131 I, and nonionic forms of 63 Ni and 125 Sb. Strontium-70 and a small fraction of the mobile 60 Co are the only cationic radionuclides which have been detected moving in the ground water plume beyond 30 meters from the source. A comparison of the observed chemical forms with the predicted species calculated from modeling thermodynamic data and ground water chemical parameters has indicated a good agreement for most of the radioelements in the system, including Tc, Np, Cs, Sr, Ce, Ru, Sb, Zn, and Mn. The discrepancies between observed and calculated solutions species were noted for Fe, Co, Ni and I. Traces of Fe, Co, and Ni were observed to migrate in anionic or nonionic forms which the calculations failed to predict. These anionic/nonionic species may be organic complexes having enhanced mobility in ground waters. The radioiodine, for example, was shown to behave totally as an anion but further investigation revealed that 49-57% of this anionic iodine was organically bound. The ground water and aqueous extracts of trench sediments contain a wide variety of organic compounds, some of which could serve as complexing agents for the radionuclides. These results indicate the need for further research at a variety of field sites in defining precisely the chemical forms of the mobile radionuclide species, and in better understanding the role of dissolved organic materials in ground water transport of radionuclides

Exposure to radionuclides in smoke from vegetation fires

Energy Technology Data Exchange (ETDEWEB)

Carvalho, Fernando P., E-mail: carvalho@itn.pt; Oliveira, João M.; Malta, Margarida

2014-02-01

Naturally occurring radionuclides of uranium, thorium, radium, lead and polonium were determined in bushes and trees and in the smoke from summer forest fires. Activity concentrations of radionuclides in smoke particles were much enriched when compared to original vegetation. Polonium-210 ({sup 210}Po) in smoke was measured in concentrations much higher than all other radionuclides, reaching 7255 ± 285 Bq kg{sup −1}, mostly associated with the smaller size smoke particles (< 1.0 μm). Depending on smoke particle concentration, {sup 210}Po in surface air near forest fires displayed volume concentrations up to 70 mBq m{sup −3}, while in smoke-free air {sup 210}Po concentration was about 30 μBq m{sup −3}. The estimated absorbed radiation dose to an adult member of the public or a firefighter exposed for 24 h to inhalation of smoke near forest fires could exceed 5 μSv per day, i.e, more than 2000 times above the radiation dose from background radioactivity in surface air, and also higher than the radiation dose from {sup 210}Po inhalation in a chronic cigarette smoker. It is concluded that prolonged exposure to smoke allows for enhanced inhalation of radionuclides associated with smoke particles. Due to high radiotoxicity of alpha emitting radionuclides, and in particular of {sup 210}Po, the protection of respiratory tract of fire fighters is strongly recommended. - Highlights: • Natural radionuclides in vegetation are in low concentrations. • Forest fires release natural radionuclides from vegetation and concentrate them in inhalable ash particles. • Prolonged inhalation of smoke from forest fires gives rise enhanced radiation exposure of lungs especially due to polonium. • Respiratory protection of fire fighters and members of public is highly recommended for radioprotection reasons.

Synthesis and antimicrobial activity of gold nanoparticle conjugates with cefotaxime

Science.gov (United States)

Titanova, Elena O.; Burygin, Gennady L.

2016-04-01

Gold nanoparticles (GNPs) have attracted significant interest as a novel platform for various applications to nanobiotechnology and biomedicine. The conjugates of GNPs with antibiotics and antibodies were also used for selective photothermal killing of protozoa and bacteria. Also the conjugates of some antibiotics with GNPs decreased the number of bacterial growing cells. In this work was made the procedure optimization for conjugation of cefotaxime (a third-generation cephalosporin antibiotic) with GNPs (15 nm) and we examined the antimicrobial properties of this conjugate to bacteria culture of E. coli K-12. Addition of cefotaxime solution to colloidal gold does not change their color and extinction spectrum. For physiologically active concentration of cefotaxime (3 μg/mL), it was shown that the optimum pH for the conjugation was more than 9.5. A partial aggregation of the GNPs in saline medium was observed at pH 6.5-7.5. The optimum concentration of K2CO3 for conjugation cefotaxime with GNPs-15 was 5 mM. The optimum concentration of cefotaxime was at 0.36 μg/mL. We found the inhibition of the growth of E. coli K12 upon application cefotaxime-GNP conjugates.

Review Paper of Radionuclide Monitoring in Food Sample

International Nuclear Information System (INIS)

Noor Fadzilah Yusof; Abdul Kadir Ishak; Wo, Y.M.; Nurrul Assyikeen Mohd Jaffary

2011-01-01

The uncontrolled release of radionuclides into the atmospheric and aquatic environments may occur as the result of a nuclear or radiological accident. Monitoring of the accidental release at its source and especially direct monitoring of the environmental contamination with radionuclides is necessary for assessment and application of public protective actions and longer term countermeasures as well as emergency workers' protection. In areas historically contaminated with long lived radionuclides monitoring it is essential to protect the public and substantiation of any radiological incidents. Also, dietary pathways can be contaminated with radioactive materials resulting from natural occurrence or man-made applications especially during routine operation, accidents and migration of radionuclides from radioactive waste disposal repositories into the biosphere. Therefore, efforts should be made to determine the presence of radionuclides in a potentially high radiation area especially in operational nuclear facilities. This paper will review the strategies for food monitoring that has been adapted in most countries to obtain baseline data for future reference. Also, this study is discussing the type of food selection commonly collected as sample for radionuclide analysis in different countries over the years. Sampling procedure and analysis also included in this review for better understanding of the analysis. Stake holders' involvement is considered as an important asset in the establishment of monitoring strategies. As a conclusion, future plans for food monitoring programme in Malaysia are recommended as a preparation to embark on the Nuclear Power Plant programme. (author)

Human dose pathways of radionuclides in forests; Forests ecosystems

Energy Technology Data Exchange (ETDEWEB)

Rantavaara, A. (Radiation and Nuclear Safety Authority, Research and Environmental Surveillance, Helsinki (Finland))

2009-06-15

Forest soil, understorey vegetation and trees are all sources of radionuclides and human radiation doses after contaminating atmospheric deposition. People are exposed to radiation externally from sources outside the body and internally via ingestion and inhalation of radionuclides. Understorey vegetation contributes to ingestion doses through berries, herbs, wild honey, mushrooms and game meat; also trees provide feed to terrestrial birds and big game. During stay in forests people are subject to external radiation from forest floor and overstorey, and they may inhale airborne radioactive aerosol or gaseous radionuclides in ground level air. In the early phase of contamination also resuspended radionuclides may add to the internal dose of people via inhalation. People in Nordic countries are most exposed to radiation via ingestion of radionuclides in wild foods. The distribution of radionuclides in forests is changed by environmental processes, and thereby also the significance of various dose pathways to humans will change with time. External exposure is received in living environment from contaminated stemwood used as building timber and for manufacturing of furniture and other wood products. The aim of this paper is to outline the significance of various human dose pathways of radionuclides in forests considering the public and workers in forestry and production of bioenergy. Examples on effective doses are given based on two historical events, atmospheric nuclear weapon tests (mostly in 1950's and in 1960's) and the Chernobyl nuclear power plant accident in 1986. (au)

TURVA-2012: Formulation of radionuclide release scenarios

International Nuclear Information System (INIS)

Marcos, Nuria; Hjerpe, Thomas; Snellman, Margit; Ikonen, Ari; Smith, Paul

2014-01-01

TURVA-2012 is Posiva's safety case in support of the Preliminary Safety Analysis Report (PSAR) and application for a construction licence for a repository for disposal of spent nuclear fuel at the Olkiluoto site in south-western Finland. This paper gives a summary of the scenarios and the methodology followed in formulating them as described in TURVA-2012: Formulation of Radionuclide Release Scenarios (Posiva, 2013). The scenarios are further analysed in TURVA-2012: Assessment of Radionuclide Release Scenarios for the Repository System and TURVA-2012: Biosphere Assessment (Posiva, 2012a, 2012b). The formulation of scenarios takes into account the safety functions of the main barriers of the repository system and the uncertainties in the features, events, and processes (FEP) that may affect the entire disposal system (i.e. repository system plus the surface environment) from the emplacement of the first canister until the far future. In the report TURVA-2012: Performance Assessment (2012d), the performance of the engineered and natural barriers has been assessed against the loads expected during the evolution of the repository system and the site. Uncertainties have been identified and these are taken into account in the formulation of radionuclide release scenarios. The uncertainties in the FEP and evolution of the surface environment are taken into account in formulating the surface environment scenarios used ultimately in estimating radiation exposure. Formulating radionuclide release scenarios for the repository system links the reports Performance Assessment and Assessment of Radionuclide Release Scenarios for the Repository System. The formulation of radionuclide release scenarios for the surface environment brings together biosphere description and the surface environment FEP and is the link to the assessment of the surface environment scenarios summarised in TURVA-2012: Biosphere Assessment. (authors)

Radionuclides, radiotracers and radiopharmaceuticals for in vivo diagnosis

International Nuclear Information System (INIS)

Wiebe, L.I.

1984-01-01

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

Radionuclides, radiotracers and radiopharmaceuticals for in vivo diagnosis

Science.gov (United States)

Wiebe, Leonard I.

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

Conjugated Polymer Solar Cells

National Research Council Canada - National Science Library

Paraschuk, Dmitry Y

2006-01-01

This report results from a contract tasking Moscow State University as follows: Conjugated polymers are promising materials for many photonics applications, in particular, for photovoltaic and solar cell devices...

Estimation of total error in DWPF reported radionuclide inventories. Revision 1

International Nuclear Information System (INIS)

Edwards, T.B.

1995-01-01

The Defense Waste Processing Facility (DWPF) at the Savannah River Site is required to determine and report the radionuclide inventory of its glass product. For each macro-batch, the DWPF will report both the total amount (in curies) of each reportable radionuclide and the average concentration (in curies/gram of glass) of each reportable radionuclide. The DWPF is to provide the estimated error of these reported values of its radionuclide inventory as well. The objective of this document is to provide a framework for determining the estimated error in DWPF's reporting of these radionuclide inventories. This report investigates the impact of random errors due to measurement and sampling on the total amount of each reportable radionuclide in a given macro-batch. In addition, the impact of these measurement and sampling errors and process variation are evaluated to determine the uncertainty in the reported average concentrations of radionuclides in DWPF's filled canister inventory resulting from each macro-batch

Characterization of Tumor-Avid Antibody Fragments Genetically Engineered for Mono-Specific Radionuclide Chelation

International Nuclear Information System (INIS)

Quinn, T.P.

2003-01-01

The successful clinical application of targeted-radiopharmaceuticals depends on the development of molecules that optimize tumor specific radionuclide deposition and minimize non-specific organ irradiation. To this end, this proposal outlines a research effort to identify and evaluate novel antibodies and antibody fragments that bind breast tumors. The tumor-avid antibodies will be investigated for as imaging and therapeutic agents and to gain a better understanding of the pharmacokinetics and metabolism of radiolabeled tumor-avid antibody fragments through the use of site-specifically labeled molecules. Antibodies or antibody fragments, that bind breast carcinoma carbohydrate antigens, will be obtained from hybridoma or bacteriophage library screening. More specifically, antibody fragments that bind the carcinoma-associated Thomsen-Friedenreich (T) antigen will be radiolabeled with 99m Tc and 188 Re at a natural amino acid chelation site and will be investigated in vivo for their abilities to target human breast tumors. In addition, site-specific radiolabeled antibody fragments will be biosynthesized using misacylated suppressor tRNAs. Homogeneously radiolabeled populations of antibody fragments will be used to investigate the effects of radionuclide location and chelation chemistries on their biodistribution and metabolism. It is hypothesized that site-specifically radiolabeled antibody fragments will possess enhanced tumor imaging and therapeutic properties due to optimal label location and conjugation chemistries. New insights into the factors that govern antibody metabolism in vivo are also expected from this work. Results from these studies should enhance our ability to design and synthesize radiolabeled antibody fragments that have improved pharmacokinetic properties. The studies in this proposal involve basic research into the development of antibody-based radiopharmaceuticals, with the ultimate goal of application in humans. This type of basic nuclear

Exposure-dose research for radionuclides in natural gas

International Nuclear Information System (INIS)

McNelis, D.N.; Patzer, R.G.

1969-01-01

The fate determination of specific radionuclides in natural gas stimulated by underground engineering applications is being examined. An experimental program, now in its initial stages, is using gas artificially labeled with krypton-85 and tritium under simulated domestic situations. The following topics are being investigated in this study: 1. The concentration of the radionuclides in a gas-heated home. 2. The build-up of contamination on appliances in the kitchen environment. 3. The concentration in foods as a function of radionuclide, food type and preparation. 4. The maximum exposure plausible under specified conditions. (author)

Biokinetics of radionuclides and treatment of accidental intakes

International Nuclear Information System (INIS)

Taylor, D.M.; Stradling, G.N.; Menetrier, F.

2003-01-01

This paper describes the objectives and reviews the progress of EULEP Working Party 5, convened under the auspices of the European Union's Fifth Framework Programme, to 'cluster' two EU-supported contracts, Biokinetics and Dosimetry of Internal Contamination (BIODOS (EU Contract FIS5-1999-00214)) and Radionuclide Biokinetics Database (EULEP) ( RBDATA-EULEP (Concerted Action Contract FIS5-1999-00218), and two non-EU funded projects, Biokinetics of Radionuclides in Human Volunteers (RNHV (non-EU Funded Project) and Treatment of Accidental Intakes of Radionuclides (TAIR (part-funded by EULEP)). (author)

Exposure-dose research for radionuclides in natural gas

Energy Technology Data Exchange (ETDEWEB)

McNelis, D N; Patzer, R G [Southwestern Radiological Health Laboratory, U.S. Public Health Service, Las Vegas, NV (United States)

1969-07-01

The fate determination of specific radionuclides in natural gas stimulated by underground engineering applications is being examined. An experimental program, now in its initial stages, is using gas artificially labeled with krypton-85 and tritium under simulated domestic situations. The following topics are being investigated in this study: 1. The concentration of the radionuclides in a gas-heated home. 2. The build-up of contamination on appliances in the kitchen environment. 3. The concentration in foods as a function of radionuclide, food type and preparation. 4. The maximum exposure plausible under specified conditions. (author)

Quality assurance in the analysis of natural radionuclides - measures and results

Energy Technology Data Exchange (ETDEWEB)

Bothe, M [Nuclear Engineering and Analytics Rossendorf, Inc. (VKTA), Dresden (Germany)

1997-03-01

In the Laboratory for Environmental and Radionuclide Analytics we analyze several natural and also some artificial radionuclides in different materials. For the determination of radionuclides we use various analytical methods. (orig./DG)

Radionuclide withdrawal from animal and human body

International Nuclear Information System (INIS)

Arkhipov, A.S.; Sidorova, T.F.

1995-01-01

The authors review the history of the problem of radionuclide withdrawal from animal and human body and discuss methodological approaches to it. Results of studies of radionuclide elimination by means of chemical and bioactive substances are analyzed. Special attention is paid to decorporation of radioactive elements which are the most hazardous as regards intoxication in connection with the Chernobyl accident: 131 I, 89 St and 90 Sr, 137 Cs, 238 Pu, and 241 Am. The authors analyze the results of studies of radionuclide withdrawal based on the dissolution effect, ionic antagonism, and by means of complexons, carried out in humans and animals. Efficacies of alimentary fibers and other adsorbents, foodstuffs and drinks are demonstrated. 48 refs

Soluble polymer conjugates for drug delivery.

Science.gov (United States)

Minko, Tamara

2005-01-01

The use of water-soluble polymeric conjugates as drug carriers offers several possible advantages. These advantages include: (1) improved drug pharmacokinetics; (2) decreased toxicity to healthy organs; (3) possible facilitation of accumulation and preferential uptake by targeted cells; (4) programmed profile of drug release. In this review, we will consider the main types of useful polymeric conjugates and their role and effectiveness as carriers in drug delivery systems.: © 2005 Elsevier Ltd . All rights reserved.

Diffeomorphisms Holder conjugate to Anosov diffeomorphisms

OpenAIRE

Gogolev, Andrey

2008-01-01

We show by means of a counterexample that a $C^{1+Lip}$ diffeomorphism Holder conjugate to an Anosov diffeomorphism is not necessarily Anosov. The counterexample can bear higher smoothness up to $C^3$. Also we include a result from the 2006 Ph.D. thesis of T. Fisher: a $C^{1+Lip}$ diffeomorphism Holder conjugate to an Anosov diffeomorphism is Anosov itself provided that Holder exponents of the conjugacy and its inverse are sufficiently large.

Radionuclide concentrations in white sturgeon from the Columbia River

Energy Technology Data Exchange (ETDEWEB)

Dauble, D.D.; Price, K.R.; Poston, T.M.

1992-09-01

Although radioactive releases from the US Department of Energy`s Hanford Site have been monitored in the environment since the reactors began operating in 1945, recent information regarding historical releases of radionuclides has led to renewed interest in estimating human exposure to radionuclides at Hanford. Knowledge of the fate of radionuclides in some fish species may be important because of the potential for food-chain transfer to humans. White sturgeon (Acipenser transmontanus) were selected for study because they are long-lived, reside year-round in the Hanford Reach, are benthic, and are an important commercial and sport species in the Columbia River. They also have a greater potential for accumulating persistent radionuclides than shorter-lived species with pelagic and/or anadromous life histories. The purpose of our study was to summarize data on historical concentrations of industrial radionuclides in white sturgeon and to collect additional data on current body burdens in the Columbia River.

Radionuclide concentrations in white sturgeon from the Columbia River

Energy Technology Data Exchange (ETDEWEB)

Dauble, D.D.; Price, K.R.; Poston, T.M.

1992-09-01

Although radioactive releases from the US Department of Energy's Hanford Site have been monitored in the environment since the reactors began operating in 1945, recent information regarding historical releases of radionuclides has led to renewed interest in estimating human exposure to radionuclides at Hanford. Knowledge of the fate of radionuclides in some fish species may be important because of the potential for food-chain transfer to humans. White sturgeon (Acipenser transmontanus) were selected for study because they are long-lived, reside year-round in the Hanford Reach, are benthic, and are an important commercial and sport species in the Columbia River. They also have a greater potential for accumulating persistent radionuclides than shorter-lived species with pelagic and/or anadromous life histories. The purpose of our study was to summarize data on historical concentrations of industrial radionuclides in white sturgeon and to collect additional data on current body burdens in the Columbia River.

Radionuclide concentrations in white sturgeon from the Columbia River

International Nuclear Information System (INIS)

Dauble, D.D.; Price, K.R.; Poston, T.M.

1992-09-01

Although radioactive releases from the US Department of Energy's Hanford Site have been monitored in the environment since the reactors began operating in 1945, recent information regarding historical releases of radionuclides has led to renewed interest in estimating human exposure to radionuclides at Hanford. Knowledge of the fate of radionuclides in some fish species may be important because of the potential for food-chain transfer to humans. White sturgeon (Acipenser transmontanus) were selected for study because they are long-lived, reside year-round in the Hanford Reach, are benthic, and are an important commercial and sport species in the Columbia River. They also have a greater potential for accumulating persistent radionuclides than shorter-lived species with pelagic and/or anadromous life histories. The purpose of our study was to summarize data on historical concentrations of industrial radionuclides in white sturgeon and to collect additional data on current body burdens in the Columbia River

Fukushima Daiichi Radionuclide Inventories

Energy Technology Data Exchange (ETDEWEB)

Cardoni, Jeffrey N. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Jankovsky, Zachary Kyle [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

2016-09-01

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

Model of the long-term transfer of radionuclides in forests

Energy Technology Data Exchange (ETDEWEB)

Avila, Rodolfo [Facilia AB, Bromma (Sweden)

2006-05-15

This report describes a model of the long-term behaviour in temperate and boreal forests of radionuclides entering the ecosystem with subsurface water. The model can be applied for most radionuclides that are of relevance in safety assessment of repositories for high-level radioactive waste. The model can be used for estimating radionuclide concentrations in soil, trees, understorey plants, mushrooms and forest mammals. A recommended (nominal) value and an interval of variation are provided for each model parameter and a classification of parameters by the degree of confidence in the values is given. Model testing against existing empirical data showing satisfactory results is also presented. Forests can play an important role in the spatial and temporal distribution of radionuclides in the environment. Despite of this, forest ecosystems have not been addressed in previous safety assessments. This can be explained by the fact that a suitable model of the long-term transfer of a wide range of radionuclides in forests has not been readily available. The objective of this work was to develop a forest model applicable for a wide range of radionuclides of relevance for high level radioactive waste management (Am-241, Cl-36, Cs-135, I-129, Ni-59, Np-237, Pu-239, Ra-226, Sr-90, Tc-99, Th-232, U-238) that can potentially enter the ecosystem with contaminated groundwater. The model assumes that biomass growth, precipitation and evapo-transpiration drive the radionuclide cycling in the system by influencing the uptake of radionuclides by vegetation and their export from the system via runoff. The mathematical model of radionuclide transfer consists of a system of ordinary differential describing the mass balance in different forest compartments, taking into account the fluxes in and out from the compartment and the radionuclides decay. The fluxes between compartments are calculated by multiplying a transfer coefficient (TC) by the radionuclide inventory in the compartment

Model of the long-term transfer of radionuclides in forests

International Nuclear Information System (INIS)

Avila, Rodolfo

2006-05-01

This report describes a model of the long-term behaviour in temperate and boreal forests of radionuclides entering the ecosystem with subsurface water. The model can be applied for most radionuclides that are of relevance in safety assessment of repositories for high-level radioactive waste. The model can be used for estimating radionuclide concentrations in soil, trees, understorey plants, mushrooms and forest mammals. A recommended (nominal) value and an interval of variation are provided for each model parameter and a classification of parameters by the degree of confidence in the values is given. Model testing against existing empirical data showing satisfactory results is also presented. Forests can play an important role in the spatial and temporal distribution of radionuclides in the environment. Despite of this, forest ecosystems have not been addressed in previous safety assessments. This can be explained by the fact that a suitable model of the long-term transfer of a wide range of radionuclides in forests has not been readily available. The objective of this work was to develop a forest model applicable for a wide range of radionuclides of relevance for high level radioactive waste management (Am-241, Cl-36, Cs-135, I-129, Ni-59, Np-237, Pu-239, Ra-226, Sr-90, Tc-99, Th-232, U-238) that can potentially enter the ecosystem with contaminated groundwater. The model assumes that biomass growth, precipitation and evapo-transpiration drive the radionuclide cycling in the system by influencing the uptake of radionuclides by vegetation and their export from the system via runoff. The mathematical model of radionuclide transfer consists of a system of ordinary differential describing the mass balance in different forest compartments, taking into account the fluxes in and out from the compartment and the radionuclides decay. The fluxes between compartments are calculated by multiplying a transfer coefficient (TC) by the radionuclide inventory in the compartment

Conjugate Problems in Convective Heat Transfer: Review

Directory of Open Access Journals (Sweden)

Abram Dorfman

2009-01-01

Full Text Available A review of conjugate convective heat transfer problems solved during the early and current time of development of this modern approach is presented. The discussion is based on analytical solutions of selected typical relatively simple conjugate problems including steady-state and transient processes, thermal material treatment, and heat and mass transfer in drying. This brief survey is accompanied by the list of almost two hundred publications considering application of different more and less complex analytical and numerical conjugate models for simulating technology processes and industrial devices from aerospace systems to food production. The references are combined in the groups of works studying similar problems so that each of the groups corresponds to one of selected analytical solutions considered in detail. Such structure of review gives the reader the understanding of early and current situation in conjugate convective heat transfer modeling and makes possible to use the information presented as an introduction to this area on the one hand, and to find more complicated publications of interest on the other hand.

Determination of radionuclides in discharged water from gold ...

African Journals Online (AJOL)

The levels of radionuclides concentrations in discharged water from gold processing into the environment of Bogoso (Ghana) were determined using radioanalytical techniques. Radioactivity screening was first carried out to identify physical and chemical processing stages that might be concentrating the radionuclides.

The radionuclide migration model in river system

International Nuclear Information System (INIS)

Zhukova, O.M.; Shiryaeva, N.M.; Myshkina, M.K.; Shagalova, Eh.D.; Denisova, V.V.; Skurat, V.V.

2001-01-01

It was propose the model of radionuclide migration in river system based on principle of the compartmental model at hydraulically stationary and chemically equilibrium conditions of interaction of radionuclides in system water-dredge, water-sediments. Different conditions of radioactive contamination entry in river system were considered. The model was verified on the data of radiation monitoring of Iput' river

Which radionuclide, carrier molecule and clinical indication for alpha-immunotherapy?

International Nuclear Information System (INIS)

Guerard, F.; Barbet, J.; Cherel, M.; Chatal, J.-F.; Haddad, F.; Kraeber-Bodere, F.

2015-01-01

Beta-emitting radionuclides are not able to kill isolated tumor cells disseminated in the body, even if a high density of radiolabeled molecules can be targeted at the surface of these cells because the vast majority of emitted electrons deliver their energy outside the targeted cells. Alpha-particle emitting radionuclides may overcome this limitation. It is thus of primary importance to test and validate the radionuclide of choice, the most appropriate carrier molecule and the most promising clinical indication. Four α-particle emitting radionuclides have been or are clinically tested in phase I studies namely 213 Bi, 225 Ac, 212 Pb and 211 At. Clinical safety has been documented and encouraging efficacy has been shown for some of them ( 213 Bi and 211 At). 211 At has been the most studied and could be the most promising radionuclide but 225 Ac and 212 Pb are also of potential great interest. Any carrier molecule that has been labeled with β-emitting radionuclides could be labeled with alpha particle-emitting radionuclide using, for some of them, the same chelating agents. However, the physical half-life of the radionuclide should match the biological half-life of the radioconjugate or its catabolites. Finally everybody agrees, based on the quite short range of alpha particles, on the fact that the clinical indications for alpha-immunotherapy should be limited to the situation of disseminated minimal residual diseases made of small clusters of malignant cells or isolated tumor cells.

Producing new radionuclides for medicine

International Nuclear Information System (INIS)

Michaut, C.

2009-01-01

The Arronax cyclotron, a new particle accelerator dedicated to the production of radionuclides for medicine and research has been commissioned in Nantes (France). Because of its unique features: an energy of 70 MeV and an intensity of 750 μA, Arronax will produce radionuclides that can not be produce in present cyclotrons. Among others it will produce Strontium-82 and Germanium-68 that are the precursors for Rubidium-82 and Gallium-68 respectively. 20 per cent of the research works will be dedicated to other domains like radioactive wastes, the radiation biological damage and the radiation damage on electronic devices. (A.C.)

Radionuclide inventory and heat generation analysis in disposal of radioactive waste

International Nuclear Information System (INIS)

Suryanto

1997-01-01

Radionuclide inventory and heat generation analysis on spent nuclear fuel were done in order to study the potential radionuclides contributing radiological impact to human being caused by spent fuel disposal. The study was carried out using the Bateman equation of radionuclide decay chains for fission products and actinides. the results showed that Cs-137, Sr-90 and Pu-239 dominated inventory of spent fuel, in which Pu-238 and Pu-240 dominated heat generation during disposal. Accordingly, the above radionuclides could be considered as the reference radionuclides for safety analysis of spent nuclear fuel disposal (author)

Specific bile acid radioimmunoassays for separate determinations of unconjugated cholic acid, conjugated cholic acid and conjugated deoxycholic acid in serum and their clinical application

International Nuclear Information System (INIS)

Matern, S.; Gerok, W.

1977-01-01

Specific radioimmunoassays for separate determinations of serum unconjugated cholic, conjugated cholic and conjugated deoxycholic acids have been developed. Prior to the radioimmunoassay, extraction of serum bile acids was performed with Amberlite XAD-2. Unconjugated cholic acid was separated from glyco- and taurocholic acids by thin-layer chromatography. At 50% displacement of bound labeled glyco[ 3 H]cholic acid using antiserum obtained after immunization with cholic acid-bovine serum albumin-conjugate the cross-reactivity of taurocholic acid was 100%, cholic acid 80%, glycochenodeoxycholic acid 10%, chenodeoxycholic acid 7%, conjugated deoxycholic acid 3%, and conjugated lithocholic acid 3 H]cholic acid was linear on a logit-log plot from 5 to 80 pmol of unlabeled glycocholic acid. Fasting serum conjugated cholic acid in healthy subjects was 0.68 +- 0.34 μmol/l. Unconjugated cholic acid was determined by a solid phase radioimmunoassay using the cholic acid antibody chemically bound to Sepharose. The displacement curve of [ 3 H]cholic acid in the solid phase radioimmunoassay was linear on a logit-log plot from 5 to 200 pmol of unlabeled cholic acid. The coefficient of variation between samples was 5%. Fasting serum conjugated deoxycholic acid concentrations in 10 healthy subjects ranged from 0.18 to 0.92 μmol/l determined by a radioimmunoassay using antiserum obtained after immunization with deoxycholic acid-bovine serum albumin-conjugate. The clinical application of these bile acid radioimmunoassays is shown by an 'oral cholate tolerance test' as a sensitive indicator of liver function and by an 'oral cholyglycine tolerance test' as a useful test for bile acid absorption. (orig.) [de

Combining of radionuclides with constituent materials of marine algae

International Nuclear Information System (INIS)

Nakamura, Ryoichi; Nakahara, Motokazu; Ishii, Toshiaki; Ueda, Taishi; Shimizu, Chiaki.

1979-01-01

The relations between the accumulation-elimination of radionuclides and the constituent materials of marine algae were studied to determine more precisely the mechanism of the radioactive contamination of marine organisms. This will increase the information about the behavior of radionuclides in marine organisms in relation to the environmental conditions (temperature, physico-chemical state of radioisotope, and so on) and the biological conditions (feeding habits, species, and so on). Eisenia contaminated by 137 Cs and 106 Ru- 106 Rh was fractionated by solvent extraction into 6 fractions. The largest portion of 137 Cs was in the boiling water fraction; 106 Ru- 106 Rh was most extracted by 24% KOH solution. Elution patterns by Sephadex G-100 gel-filtration of samples differed largely from each other, both among the 3 kinds of radionuclides and between the 2 species of the algae. Therefore, the accumulation of the radionuclides by the marine algae was proved to be not only due to a physical absorption to the surface of the algae but also to the biological combining of the radionuclides with the constituents of the algae. Furthermore, it was found that radionuclides which combine with a few constituents of alga are not eliminated equally. This is considered to be useful for the physiological analysis of elimination curves. (author)

Development of a portable equipment for identification of radionuclides

International Nuclear Information System (INIS)

Farias, Marcos Santana; Carvalho, Paulo Victor R. de; Nedjah, Nadia; Mourelle, Luiza de Macedo

2014-01-01

The rapid and automatic identification of radionuclides present in a radioactive sample detected in the field, is information that helps in decision making. In areas of high traffic of people and materials, such as ports and airports as well as at major events, radiation monitoring, together with the identification of the radionuclide, it is advisable within protective standards to the public. The correct identification of radionuclides depends on the ability to determine whether specific peaks energy sources are present in the spectrum of gamma radiation sources. Radionuclides can be identified by these energy characteristics in the sense that the energy value associated with these peaks in the spectrum corresponds to the radiation sources present in the sample. There are many methods that can be used for automatic identification of radionuclides. Most of them are based on software algorithms for the detection of peaks in the energy spectrum. Processing time of these tasks can be very long for applications requiring quick responses, as in equipment portable. A dedicated digital hardware offers better performance for tasks with high processing demand like this. This work shows the development of a handle Portable radionuclides based on a digital hardware solution using a FPGA (Field Programmable Gate Array) for implementing a clustering algorithm for the detection of energy peaks. (author)

Tumour therapy with radionuclides: assessment of progress and problems

International Nuclear Information System (INIS)

Carlsson, Joergen; Forssell Aronsson, Eva; Hietala, Sven-Ola; Stigbrand, Torgny; Tennvall, Jan

2003-01-01

Radionuclide therapy is a promising modality for treatment of tumours of haematopoietic origin while the success for treatment of solid tumours so far has been limited. The authors consider radionuclide therapy mainly as a method to eradicate disseminated tumour cells and small metastases while bulky tumours and large metastases have to be treated surgically or by external radiation therapy. The promising therapeutic results for haematological tumours give hope that radionuclide therapy will have a breakthrough also for treatment of disseminated cells from solid tumours. New knowledge related to this is continuously emerging since new molecular target structures are being characterised and the knowledge on pharmacokinetics and cellular processing of different types of targeting agents increases. There is also improved understanding of the factors of importance for the choice of appropriate radionuclides with respect to their decay properties and the therapeutic applications. Furthermore, new methods to modify the uptake of radionuclides in tumour cells and normal tissues are emerging. However, we still need improvements regarding dosimetry and treatment planning as well as an increased knowledge about the tolerance doses for normal tissues and the radiobiological effects on tumour cells. This is especially important in targeted radionuclide therapy where the dose rates often are lower than 1 Gy/h

Fast optimal wavefront reconstruction for multi-conjugate adaptive optics using the Fourier domain preconditioned conjugate gradient algorithm.

Science.gov (United States)

Vogel, Curtis R; Yang, Qiang

2006-08-21

We present two different implementations of the Fourier domain preconditioned conjugate gradient algorithm (FD-PCG) to efficiently solve the large structured linear systems that arise in optimal volume turbulence estimation, or tomography, for multi-conjugate adaptive optics (MCAO). We describe how to deal with several critical technical issues, including the cone coordinate transformation problem and sensor subaperture grid spacing. We also extend the FD-PCG approach to handle the deformable mirror fitting problem for MCAO.

Limit of the radionuclides in granite

International Nuclear Information System (INIS)

Wang Shaling; Jiang Rangrong

2003-01-01

Granite is an important sort of building materials. Their radionuclide contents are limited by the national standard GB6566-2001 just as other building materials. This standard divides them into main materials and decorative materials, and relaxes the limit of the latter obviously. Owing to the consideration of public dose limit and environment protection, this method needs discussion. Otherwise, red granite contains high radionuclide contents relatively, especially the sort of Indian Red, and need be paid more attention

When avoiding unpleasant emotions might not be such a bad thing: verbal-autonomic response dissociation and midlife conjugal bereavement.

Science.gov (United States)

Bonanno, G A; Keltner, D; Holen, A; Horowitz, M J

1995-11-01

It has been widely assumed that emotional avoidance during bereavement leads to either prolonged grief, delayed grief, or delayed somatic symptoms. To test this view, as well as a contrasting adaptive hypothesis, emotional avoidance was measured 6 months after a conjugal loss as negative verbal-autonomic response dissociation (low self-rated negative emotion coupled with heightened cardiovascular activity) and compared with grief measured at 6 and 14 months. The negative dissociation score evidenced reliability and validity but did not evidence the assumed link to severe grief. Rather, consistent with the adaptive hypothesis, negative dissociation at 6 months was associated with minimal grief symptoms across 14 months. Negative dissociation scores were also linked to initially high levels of somatic symptoms, which dropped to a low level by 14 months. Possible explanations for the initial cost and long-term adaptive quality of emotional avoidance during bereavement, as well as implications and limitations of the findings, are discussed.

Preparation and biodistribution study of 99Tcm labelled dextran conjugates

International Nuclear Information System (INIS)

Yang Chunhui; Li Hongyu; Liang Jixin; Lu Jia; Luo Hongyi; Zheng Deqiang; Sun Guiquan

2012-01-01

99 Tc m Mannosylated dextran conjugates were prepared through [ 99 Tc m (CO) 3 ] + precursor synthesized by carbonyl Isolink kit. The labelled conjugates were injected sub-dermally into the rear foots of the mice, and the patent blue solution was injected at the same site 10 min before sacrifice. The mice were killed at 1 h and 4 h postinjection, and the samples of different tissues including SLN, 2LN, injection site, liver, spleen, blood were dissected and counted. The uptake in terms was calculated. The results of biodistribution demonstrated that the SLN uptakes of radiopharmaceutical (without mannose in the molecules) were rather low and in vivo excretion of these conjugates were comparatively faster, and the uptake of injection site was also low; on the other hand, the SLN uptakes of radio pharmaceutical (with mannose in their molecules) were much higher than those of their corresponding dextran conjugates without mannose, but the retention in the injection site of these conjugates increased too. The results indicated that the affinity of mannosyl-dextran conjugates to the receptors on the surface of macrophages in the lymph node. In addition, the different relative molecular mass of dextran conjugates also cause different biodistribution results, the major one had higher SLN uptake, the difference was significant (P 99 Tc m (CO) 3 ] + labelled mannosylated dextran conjugates showed promising properties as SLN imaging agent and worth further investigation. (authors)

Therapeutic radionuclides: Making the right choice

International Nuclear Information System (INIS)

Srivastava, S.C.

1996-01-01

Recently, there has been a resurgence of interest in nuclear medicine therapeutic procedures. Using unsealed sources for therapy is not a new concept; it has been around since the beginnings of nuclear medicine. Treatment of thyroid disorders with radioiodine is a classic example. The availability of radionuclides with suitable therapeutic properties for specific applications, as well as methods for their selective targeting to diseased tissue have, however, remained the main obstacles for therapy to assume a more widespread role in nuclear medicine. Nonetheless, a number of new techniques that have recently emerged, (e.g., tumor therapy with radiolabeled monoclonal antibodies, treatment of metastatic bone pain, etc.) appear to have provided a substantial impetus to research on production of new therapeutic radionuclides. Although there are a number of new therapeutic approaches requiring specific radionuclides, only selected broad areas will be used as examples in this article

EPA perspective on radionuclide aerosol sampling

Energy Technology Data Exchange (ETDEWEB)

Karhnak, J.M. [Environmental Protection Agency, Washington, DC (United States)

1995-02-01

The Environmental Protection Agency (EPA) is concerned with radionuclide aerosol sampling primarily at Department of Energy (DOE) facilities in order to insure compliance with national air emission standards, known as NESHAPs. Sampling procedures are specified in {open_quotes}National Emission Standards for Emissions of Radionuclides other than Radon from Department of Energy Sites{close_quotes} (Subpart H). Subpart H also allows alternate procedures to be used if they meet certain requirements. This paper discusses some of the mission differences between EPA and Doe and how these differences are reflected in decisions that are made. It then describes how the EPA develops standards, considers alternate sampling procedures, and lists suggestions to speed up the review and acceptance process for alternate procedures. The paper concludes with a discussion of the process for delegation of Radionuclide NESHAPs responsibilities to the States, and responsibilities that could be retained by EPA.

Mass spectrometry of long-lived radionuclides

International Nuclear Information System (INIS)

Becker, Johanna Sabine.

2003-01-01

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

RADIONUCLIDES DISTRIBUTION NEAR FORMER URANIUM MINING

Directory of Open Access Journals (Sweden)

D. A. Zaredinov

2016-01-01

Full Text Available The paper shows, that radionuclides from the stony rocks of uranium mines can be leached by atmospheric precipitations. In acid conditions, a degree of leaching is greater.Goal. The aim of this investigation was to study the distribution of radionuclides in uranium minings and their impact on the environmental contamination.Materials and methods. The study was carried out in two stages. In the first stage, a blade of rock was mixed with distilled water in proportions of 0,3 kg of gravel and 1 liter of water. After thirty days of soaking, water was sent to the gamma-spectrometric analysis to Canberra’s spectrometer (USA with a high-purity germanium detector. In the second stage, we carried out the similar experiment with water, wich was acidified to pH = 3. Contamination levels of areas near the in-situ leaching mine were determined. Intervention levels were used to estimate risk and possible water consumption by the population. Estimations were carried out taking into account the combined presence of several radionuclides in the water.Results. The results of these studies have shown that the distribution of radionuclides from the source of the contamination is about 360 meters during the 30 y period. The stream, along which samples of soil were collected and studied, was formed by the miner waters that flow along small ruts towards a village, thereby increasing the likelihood of water use by the public.Conclusions. The uranium mines are the source of radioactive contamination. Radionuclides are distributed due to the erosion of rocks and leached out of the stony rock by precipitations. The extent of leaching is significantly increased in an acidic environment, which takes place near the in-situ leaching mines.

Transfer of radionuclides to plants[Radioecology

Energy Technology Data Exchange (ETDEWEB)

Nielsen, Sven P. [Risoe National Lab., Roskilde (Denmark)

2006-04-15

Sampling of Water Horsetail and Bracken Fern including upper soil layer (0-10 cm) and water was carried out in Torahult, Sweden, in Almindingen on Bornholm, in Asserbo and Arresoe on Zealand and in Sdr. Hostrup and Nydam mose in Jutland. Furthermore, sampling was carried out in 2004 for seawater, seaweed and shrimps at locations in Danish waters at Bornholm (Svenskehavn), at Zealand (Klint), at Lolland/Falster (Guldborgsund) and on the west coast of Jutland (Hirtshals, Agger, Hvide Sande and Roemoe). Concentrations of gamma-emitting radionuclides and uranium were determined in Bracken Fern, Water Horsetail and soil samples. The concentration ratios (CR) are highest for {sup 40}K in both plant species and show the lowest variability across locations. The CR's for 40K range from 1 to 2, while the CR's for the other radionuclides range one to three orders of magnitude lower. The CR's for {sup 137}Cs show particularly high variability across locations. The CR's were analysed in a two-way ANOVA on the log-transformed values to test differences between plant species and radionuclides. The difference between radionuclides was highly significant, p<0.01, whereas the difference between plant species was not significant. The concentration ratios are listed by radionuclide showing geometric mean values and geometric standard deviations. Analyses were made of {sup 137}Cs and {sup 99}Tc in marine samples. Concentration ratios calculated from the analysed samples are presented. The concentration ratios for {sup 99}Tc agree with those reported elsewhere in the Indofern Project. The concentration ratios for {sup 137}Cs in Fucus show a correlation to salinity with higher values in low salinity water at Bornholm than in high salinity water on the west coast of Jutland. (LN)

2006 LANL Radionuclide Air Emissions Report

Energy Technology Data Exchange (ETDEWEB)

David P. Fuehne

2007-06-30

This report describes the impacts from emissions of radionuclides at Los Alamos National Laboratory (LANL) for calendar year 2006. This report fulfills the requirements established by the Radionuclide National Emissions Standards for Hazardous Air Pollutants (Rad-NESHAP). This report is prepared by LANL's Rad-NESHAP compliance team, part of the Environmental Protection Division. The information in this report is required under the Clean Air Act and is being reported to the U.S. Environmental Protection Agency (EPA). The highest effective dose equivalent (EDE) to an off-site member of the public was calculated using procedures specified by the EPA and described in this report. LANL's EDE was 0.47 mrem for 2006. The annual limit established by the EPA is 10 mrem per year. During calendar year 2006, LANL continuously monitored radionuclide emissions at 28 release points, or stacks. The Laboratory estimates emissions from an additional 58 release points using radionuclide usage source terms. Also, LANL uses a network of air samplers around the Laboratory perimeter to monitor ambient airborne levels of radionuclides. To provide data for dispersion modeling and dose assessment, LANL maintains and operates meteorological monitoring systems. From these measurement systems, a comprehensive evaluation is conducted to calculate the EDE for the Laboratory. The EDE is evaluated as any member of the public at any off-site location where there is a residence, school, business, or office. In 2006, this location was the Los Alamos Airport Terminal. The majority of this dose is due to ambient air sampling of plutonium emitted from 2006 clean-up activities at an environmental restoration site (73-002-99; ash pile). Doses reported to the EPA for the past 10 years are shown in Table E1.

Production of radionuclides with generators

International Nuclear Information System (INIS)

Khujaev, S.; Egamediev, S.Kh.

2004-01-01

Full text: The radionuclide generator provides a convenient means for researchers and clinicians to obtain a source of radionuclides without dependence on nuclear facilities (nuclear reactor or cyclotron). It should be noted that radionuclide generator technique yields products of very high purity and it offers moreover the only possible way of obtaining very short-lived radionuclides for practical applications. Therefore at present radionuclide generators have found important uses in nuclear medicine. This talk reviews the development of preparation methods for radionuclide generators of current interest: 99 Mo- 99m Tc, 188 W- 188 Re and 68 Ge- 68 Ga. 99 Mo- 99m Tc generator. 99m Tc is presently the most widely used radionuclide in diagnostic nuclear medicine. The reason for such a preeminent position of 99m Tc in clinical uses is its extremely favorable nuclear properties with γ-energy of 140 keV and short half-life of 6 hours. Chromatographic generator of 99 Mo- 99m Tc based on aluminium oxide using as eluent of isotonic saline solution, containing nitrate-ions has been produced in INP AS RU. However, the main disadvantage of this generator is that the eluent-saline solution contains some amount of nitrate-ions. Nitrate-ions added to maximize and stabilize 99m Tc yields would interfere with the chemical reactions which involve Sn(II) reduction of the pertechnetate ion and which are used subsequently in the preparation of radiopharmaceuticals. Therefore we proposed the new method for preliminary treatment of aluminium oxide by the external gamma (Co-60) irradiation. It is found that the aluminium oxide has got electron-acceptor properties after gamma-irradiation. Adsorption of 99 Mo radionuclide as isopolymolybdate on gamma-irradiated aluminium oxide is very high and molybdenum is firmly retained. Adsorption capacity of gamma-irradiated aluminium oxide at pH 2-4 is 60-80 mg Mo per gram of Al 2 O 3 . The yields of 99m Tc from experimental generators remained high

Monitoring of radionuclides in the air of Monaco during 1997-1998

International Nuclear Information System (INIS)

Pham, M.K.; Povinec, P.P.; Huynh Ngoc, L.

1999-01-01

IAEA-MEL has been carried out monitoring of radionuclides in the air of Monaco for several years. Several natural (cosmogenic, radiogenic and primordial) and anthropogenic radionuclides are found in the atmosphere. The measurement of these radionuclides in the atmosphere is helping to study their temporal variations and to estimate their deposition rates to oceans and to seas. We report here concentrations of some radionuclides in air of Monaco during 1997-1998

Functional properties of nisin–carbohydrate conjugates formed by radiation induced Maillard reaction

International Nuclear Information System (INIS)

Muppalla, Shobita R.; Sonavale, Rahul; Chawla, Surinder P.; Sharma, Arun

2012-01-01

Nisin–carbohydrate conjugates were prepared by irradiating nisin either with glucose or dextran. Increase in browning and formation of intermediate products was observed with a concomitant decrease in free amino and reducing sugar groups indicating occurrence of the Maillard reaction catalyzed by irradiation. Nisin–carbohydrate conjugates showed a broad spectrum antibacterial activity against Gram negative bacteria (Escherichia coli, Pseudomonas fluorescence) as well as Gram positive bacteria (Staphylococcus aureus, Bacillus cereus). Results of antioxidant assays, including that of DPPH radical-scavenging activity and reducing power, showed that the nisin–dextran conjugates possessed better antioxidant potential than nisin–glucose conjugate. These results suggested that it was possible to enhance the functional properties of nisin by preparing radiation induced conjugates suitable for application in food industry. - Highlights: ► Nisin–carbohydrate conjugates were prepared using radiation induced Maillard reaction. ► Conjugation of nisin with dextran/glucose resulted in improvement of antibacterial spectrum. ► Conjugates of nisin with dextran/glucose had significant radical scavenging activity.

Transfer coefficients of radionuclides secreted in milk of dairy cows

International Nuclear Information System (INIS)

Sam, D.; Williams, W.F.; Rockmann, D.D.; Allen, J.T.

1980-01-01

This study simulated experimentally the transfer of radionuclides to milk of dairy cows on a worst-case situation using various radionuclides known to emanate from nuclear power stations and which have been detected on particulates. Two lactating Holstein cows were administered orally one gelatin capsule containing 10 radionuclides in water-soluble form per day for 14 consecutive days. Milk samples were collected and aliquots analyzed in a germanium lithium-drifted detector coupled to a 2048-multichannel gamma-ray analyzer to measure small amounts of complex mixtures of radionuclides. The transfer coefficients of the radionuclides were calculated when their secretion in milk reached or approached a plateau of concentration. The radionuclides and their transfer coefficients to milk were: chromium 51 less than 0.01%; manganese 54 0.033 +- 0.005%; cobalt 60 0.01 +- 0.002%; iron 59 0.0048 +- 0.002%; zinc 65 0.31 +- 0.07%; selenium 75 0.29 +- 0.1%; antimony 125 0.011 +- 0.003%; iodine 131 0.88 +- 0.05%; and cesium 137 0.79 +- 0.08%

Cross-conjugation and quantum interference: a general correlation?

DEFF Research Database (Denmark)

Valkenier, Hennie; Guedon, Constant M.; Markussen, Troels

2014-01-01

We discuss the relationship between the pi-conjugation pattern, molecular length, and charge transport properties of molecular wires, both from an experimental and a theoretical viewpoint. Specifically, we focus on the role of quantum interference in the conductance properties of cross-conjugated...

Behaviour and fate radionuclides in soils. Mathematical modelling and experimental investigations

International Nuclear Information System (INIS)

Rovdan, E.N.

2003-01-01

The uncontrolled release of radionuclides as result of Chernobyl accident has led to contamination of 23% of territory of Republic of Belarus. Soil has high capacity to adsorb radionuclides and their intensive sorption provides the creation of a long-lived radionuclide source in a terrestrial environment. In the management of the contaminated areas and application of a countermeasure strategy it is extremely important to know the environmental mechanisms governing the behaviour of radionuclides in soils. Basic attention in the work is paid to the study of 137 Cs and 90 Sr because they are the main radionuclides from the view point of radioactive danger in polluted areas. The main features and processes that control radionuclide behaviour in soil have been analysed. On the basis of natural researches, lab test and mathematical modelling the impact of physical-chemical factors and the soil component composition changes upon the radionuclides migration and sorption in natural dispersed systems (peat, sand, bentonite, kaolin, sapropel) has been investigated. The investigations done allowed to substantiate the mathematical models of the radionuclides migration in the regions of positive and negative temperatures, to develop methods of experimental identification of main transfer characteristics and to compile a data base for these models. (orig.)

Identification of key radionuclides in a nuclear waste repository in basalt

International Nuclear Information System (INIS)

Barney, G.S.; Wood, B.J.

1980-05-01

Radionuclides were identified which appear to pose the greatest potential hazard to man during long-term storage of nuclear waste in a repository mined in the Columbia Plateau basalt formation. The criteria used to select key radionuclides were as follows: quantity of radionuclide in stored waste; biological toxicity; leach rate of the wastes into groundwater; and transport rate via groundwater flow. The waste forms were assumed to be either unreprocessed spent fuel or borosilicate glass containing reprocessed high-level waste. The nuclear waste composition was assumed to be that from a light water reactor. Radionuclides were ranked according to quantity, toxicity, and release rate from the repository. These rankings were combined to obtain a single list of key radionuclides. The ten most important radionuclides in order of decreasing hazard are: 99 Tc, 129 I, 237 Np, 226 Ra, 107 Pd, 230 Th, 210 Pb, 126 Sn, 79 Se, and 242 Pu. Safety assessment studies and the design of engineered barriers should concentrate on containment of radionuclides in this list

CRRIS: a methodology for assessing the impact of airborne radionuclide releases

International Nuclear Information System (INIS)

Baes, C.F. III; Miller, C.W.

1983-01-01

The Computerized Radiological Risk Investigation System (CRRIS) consists of six fully integrated computer codes which calculate environmental transport and resulting doses and risks to individuals or populations exposed to atmospheric radionuclide releases. The individual codes may be used alone for various assessment applications or may be run as a system. This presentation provides an overview and introduction to this system of computer codes and their use in conducting nuclear assessments. Radionuclides are handled by CRRIS either in terms of the released radionuclides or in terms of exposure radionuclides which consist of both the released nuclides and all (or a subset of) the decay daughters that grow in during environmental transport. The capability of CRRIS to handle radionuclide chains is accomplished through PRIMUS which serves as a preprocessor by accessing a library of radionuclide decay data and sets up matricies of decay constants which are used by the other CRRIS codes in all calculations involving transport and decay. PRIMUS may also be run independently by the user to define the decay chains, radionuclide decay constants, and branching ratios

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

Energy Technology Data Exchange (ETDEWEB)

Hazen, Terry C.; Tabak, Henry H.

2007-03-15

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

The biotic factors role in radionuclide migration of natural-vegetable complexes

International Nuclear Information System (INIS)

Yakushev, B.I.; Kazej, A.I.; Sak, M.M.; Kuz'mich, O.T.; Golushko, R.M.

1992-01-01

In Byelorussiyn from first months after the Chernobyl' accident investigation are conducting on the radionuclide de dynamics in the soil-plant-soil system. The isotope composition of soil contamination density and specific plants radioactivity are studying, the radionuclide migration dynamic through the soil profile is investigating. The data are shown on considerable reduction of the plants radioactivity (1986-91 years) in connection with the reduction in the soil contamination density with gamma-spectrum radionuclides, accounting for Ce-144, Pr-144, Ru-106, Cs-134 decay; information is done on gamma-spectrum radionuclides of organs in natural pine and meadows system. It is shown, that the radionuclides are actively absorbed by roots in a zone of the highest radionuclide concentration and are delivered into the overground plant parts, then actively are removed into environment in the breathing process. 11 refs.; 4 tabs

Behaviour of uranium series radionuclides in surface water (Crouzille, Limousin). Geochemical implications

International Nuclear Information System (INIS)

Moulin, J.

2008-06-01

Understanding natural radionuclides behaviour in surface water is a required step to achieve uranium mine rehabilitation and preserve water quality. The first objective of this thesis is to determine which are the radionuclides sources in a drinking water reservoir. The second objective is to improve the knowledge about the behaviour of uranium series radionuclides, especially actinium. The investigated site is a brook (Sagnes, Limousin, France) which floods a peat bog contaminated by a former uranium mine and which empties into the Crouzille lake. It allows studying radionuclides transport in surface water and radionuclides retention through organic substance or water reservoir. Radionuclides distribution in particulate, colloidal and dissolved phases is determined thanks to ultra-filtrations. Gamma spectrometry allows measuring almost all natural radionuclides with only two counting stages. However, low activities of 235 U series radionuclides impose the use of very low background well-type Ge detectors, such as those of the Underground Laboratory of Modane (France). Firstly, this study shows that no or few radionuclides are released by the Sagnes peat bog, although its radioactivity is important. Secondly, it provides details on the behaviour of uranium series radionuclides in surface water. More specifically, it provides the first indications of actinium solubility in surface water. Actinium's behaviour is very close to uranium's even if it is a little less soluble. (author)

21 CFR 892.5650 - Manual radionuclide applicator system.

Science.gov (United States)

2010-04-01

... system. (a) Identification. A manual radionuclide applicator system is a manually operated device... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Manual radionuclide applicator system. 892.5650.... This generic type of device may include patient and equipment supports, component parts, treatment...

Radionuclide transfer from contaminated field to crops

International Nuclear Information System (INIS)

Ohmomo, Yoichiro; Tanaka, Giichiro

1987-03-01

Since the policy for land disposal of radioactive wastes were proposed, the importance of terrestrial radioecology has been re-recognized in Japan. The National Institute of Radiological Sciences (NIRS) held a Two-Day Seminar concerning terrestrial transfer of radionuclides. This is a compilation of papers presented at the seminar. The purpose of the seminar is twofold: firstly, to raise basic problems concerning transfer of not only radionuclides but also elements into crops, as well as to present NIRS's studies on radionuclide transfer; and secondly, to discuss in depth the topics about possible transfer of I-129 into rice plant arising from the commercial fuel reprocessing plant, the construction of which is under planning. Finally, general discussion of further issues on radioecology is given. (Namekawa, K.)

Enzymatic degradation behavior and cytocompatibility of silk fibroin-starch-chitosan conjugate membranes

Energy Technology Data Exchange (ETDEWEB)

Baran, Erkan T., E-mail: erkantur@metu.edu.tr; Tuzlakoglu, Kadriye, E-mail: kadriye@dep.uminho.pt; Mano, Joao F., E-mail: jmano@dep.uminho.pt; Reis, Rui L., E-mail: rgreis@dep.uminho.pt

2012-08-01

The objective of this study was to investigate the influence of silk fibroin and oxidized starch conjugation on the enzymatic degradation behavior and the cytocompatability of chitosan based biomaterials. The tensile stress of conjugate membranes, which was at 50 Megapascal (MPa) for the lowest fibroin and starch composition (10 weight percent (wt.%)), was decreased significantly with the increased content of fibroin and starch. The weight loss of conjugates in {alpha}-amylase was more notable when the starch concentration was the highest at 30 wt.%. The conjugates were resistant to the degradation by protease and lysozyme except for the conjugates with the lowest starch concentration. After 10 days of cell culture, the proliferation of osteoblast-like cells (SaOS-2) was stimulated significantly by higher fibroin compositions and the DNA synthesis on the conjugate with the highest fibroin (30 wt.%) was about two times more compared to the native chitosan. The light microscopy and the image analysis results showed that the cell area and the lengths were decreased significantly with higher fibroin/chitosan ratio. The study proved that the conjugation of fibroin and starch with the chitosan based biomaterials by the use of non-toxic reductive alkylation crosslinking significantly improved the cytocompatibility and modulated the biodegradation, respectively. - Highlights: Black-Right-Pointing-Pointer Silk fibroin, starch and chitosan conjugates were prepared by reductive alkylation. Black-Right-Pointing-Pointer The enzymatic biodegradation and the cytocompatibility of conjugates were tested. Black-Right-Pointing-Pointer The conjugate with 30% starch composition was degraded by {alpha}-amylase significantly. Black-Right-Pointing-Pointer Higher starch composition in conjugates prevented protease and lysozyme degradation. Black-Right-Pointing-Pointer Fibroin incorporation effectively increased the cell proliferation of conjugates.

Recent Advances in Conjugated Polymers for Light Emitting Devices

Science.gov (United States)

AlSalhi, Mohamad Saleh; Alam, Javed; Dass, Lawrence Arockiasamy; Raja, Mohan

2011-01-01

A recent advance in the field of light emitting polymers has been the discovery of electroluminescent conjugated polymers, that is, kind of fluorescent polymers that emit light when excited by the flow of an electric current. These new generation fluorescent materials may now challenge the domination by inorganic semiconductor materials of the commercial market in light-emitting devices such as light-emitting diodes (LED) and polymer laser devices. This review provides information on unique properties of conjugated polymers and how they have been optimized to generate these properties. The review is organized in three sections focusing on the major advances in light emitting materials, recent literature survey and understanding the desirable properties as well as modern solid state lighting and displays. Recently, developed conjugated polymers are also functioning as roll-up displays for computers and mobile phones, flexible solar panels for power portable equipment as well as organic light emitting diodes in displays, in which television screens, luminous traffic, information signs, and light-emitting wallpaper in homes are also expected to broaden the use of conjugated polymers as light emitting polymers. The purpose of this review paper is to examine conjugated polymers in light emitting diodes (LEDs) in addition to organic solid state laser. Furthermore, since conjugated polymers have been approved as light-emitting organic materials similar to inorganic semiconductors, it is clear to motivate these organic light-emitting devices (OLEDs) and organic lasers for modern lighting in terms of energy saving ability. In addition, future aspects of conjugated polymers in LEDs were also highlighted in this review. PMID:21673938

One-dimensional radionuclide transport under time-varying conditions

International Nuclear Information System (INIS)

Gelbard, F.; Olague, N.E.; Longsine, D.E.

1990-01-01

This paper discusses new analytical and numerical solutions presented for one-dimensional radionuclide transport under time-varying fluid-flow conditions including radioactive decay. The analytical solution assumes that all radionuclides have identical retardation factors, and is limited to instantaneous releases. The numerical solution does not have these limitations, but is tested against the limiting case given for the analytical solution. Reasonable agreement between the two solutions was found. Examples are given for the transport of a three-member radionuclide chain transported over distances and flow rates comparable to those reported for Yucca Mountain, the proposed disposal site for high-level nuclear waste

Principles of radionuclide studies of the genitourinary system

International Nuclear Information System (INIS)

Kim, E.E.; Pjura, G.A.; Lowry, P.A.

1988-01-01

The clinical assessment of renal diseases with radionuclide procedures is discussed. It has achieved general recognition only during the last decade. The proper assessment of renal function with radionuclides provides useful information for the management of patients with renal disease and renal transplant recipients. Renal imaging with radionuclides gives some information on morphology and the integrity of the urinary collecting system, but more importantly it provides functional information that may include renal blood flow or effective renal plasma flow (ERPF), glomerular filtration rate (GFR), the quantitation of differential renal function, the evaluation of vesicoureteral reflux, the quantitation of postvoiding residual urine volume, and the differential diagnosis of testicular disease. Acute renal failure resulting from acute tubular necrosis, hepatorenal syndrome, acute interstitial nephirits, cortical necrosis, renal artery embolism, or acute pyelonephritis may be recognized by radionuclide studies. Data useful in the diagnosis and management of the patient with obstructive or reflux nephropathy also may be obtained. Radionuclide studies in patients with chronic renal failure may reveal such causes as renal artery stenosis, chronic pyelonephritis, or infiltrative renal disease. Finally, nuclear study in transplant recipients is useful to help differentiate rejection from acute tubular necrosis and other causes of reduced renal function

Concentration of some radionuclides in Moringa Oliefera plant

International Nuclear Information System (INIS)

Abd elbagi, W. K. A.

2013-07-01

This study has been conducted to determine the radioactivity concentration of naturally occurring radionuclides 228 U, 232 Th, and 40 K in samples of Moringaoliefera plants in Khartoum Bahry Elsamrab by using γ ray spectrometry sodium iodide detector and high purity germanium detector. A total of 30 samples, 10 samples from leaves, 10 samples from seeds and 10 samples from soil of samples have been collected. For leaves the radionuclide activity concentrations in samples analyzed with the mean of 2767.266±78.6741 Bq kg - 1 for 238 U, 3486.817±80.98811 Bq kg - 1 for 238 Th and 2273.386±54.152 Bq kg - 1 for 40 K. For seeds the radionuclide activity concentration in samples analyzed with the mean of 2839.224±72.6016 Bq kg - 1 for 238 U, 2844.372±78.74919 Bq kg - 1 for 2 38T h and 2377.005±91.8838 Bq kg - 1 for 40 K. No trace of artificial radionuclide has been determined in all the samples. The effective dose due to the presence of these radionuclides has been estimated and found 0.89μSv/year and 0.1015μSv/year for 232 Th, 238 U and 40 K, respectively.(Author)

Radionuclide solubilities at elevated temperatures. A literature study

International Nuclear Information System (INIS)

Carlsson, T.; Vuorinen, U.

1997-07-01

This literature study contains experimental data and modelling data collected in order to illustrate how temperature affects radionuclide solubilities under conditions similar to those expected in the vicinity of a planned repository for spent nuclear fuel. The elements considered were Ni, Se, Zr, Tc, Pd, Sn, Ra, Th, Pa, U, Np, Pu and Am. The temperatures of main interest are restricted to the interval between room temperature and 100 deg C. The study showed that the literature on radionuclide solubility at temperatures above room temperature is scarce. Therefore, also work that refers to conditions slightly varying from the expected repository conditions has been considered. A minor modelling exercise was done in this study in order to show the effect of temperature on the solubilities of Ni, Np and U under various conditions. The results from the literature survey and our modelling demonstrate the complexity of groundwater systems and the difficulty in finding simple and general relationships between temperature and radionuclide solubilities. Often an increase in temperature (below 100 deg C) leads to a reduction of the radionuclide solubility or leaves it roughly unchanged. However, examples are also found where the rise in temperature increases the radionuclide solubility by several orders of magnitude. (orig.)

Radionuclide solubilities at elevated temperatures. A literature study

Energy Technology Data Exchange (ETDEWEB)

Carlsson, T.; Vuorinen, U. [Technical Research Centre of Finland, Espoo (Finland)

1997-07-01

This literature study contains experimental data and modelling data collected in order to illustrate how temperature affects radionuclide solubilities under conditions similar to those expected in the vicinity of a planned repository for spent nuclear fuel. The elements considered were Ni, Se, Zr, Tc, Pd, Sn, Ra, Th, Pa, U, Np, Pu and Am. The temperatures of main interest are restricted to the interval between room temperature and 100 deg C. The study showed that the literature on radionuclide solubility at temperatures above room temperature is scarce. Therefore, also work that refers to conditions slightly varying from the expected repository conditions has been considered. A minor modelling exercise was done in this study in order to show the effect of temperature on the solubilities of Ni, Np and U under various conditions. The results from the literature survey and our modelling demonstrate the complexity of groundwater systems and the difficulty in finding simple and general relationships between temperature and radionuclide solubilities. Often an increase in temperature (below 100 deg C) leads to a reduction of the radionuclide solubility or leaves it roughly unchanged. However, examples are also found where the rise in temperature increases the radionuclide solubility by several orders of magnitude. (orig.). 54 refs.

Exposure to radionuclides in smoke from vegetation fires.

Science.gov (United States)

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

2014-02-15

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

Radionuclide Content of Pasteurized Milk Sold in Mafikeng, South Africa

International Nuclear Information System (INIS)

Olobatoke, R.; Mathuthu, M.

2015-01-01

Many food animals which are important components of human food chain are effective collectors of radionuclides from the environment particularly contaminated forages, and therefore represent a significant pathway for the transfer of radionuclides to humans. Many important radionuclides are readily transferred to milk thus the product is considered as one of the basic food items recommended for the assessment of radionuclide exposure within a population. The current study aimed at assessing the radionuclide content of commercial milk commonly sold in South Africa in other to set a baseline data for radionuclide concentration of the products. Three popular brands of commercial milk (A, B and C) were sampled, with two samples obtained for each brand. The concentration of individual radionuclide in the milk samples, particularly "1"3"1I, "1"3"7Cs and "2"3"5U was measured by gamma spectroscopy. The results showed that brand A had the highest concentrations of "2"3"5U and "1"3"7Cs (203 and 324 mBq/l respectively) but the lowest concentration of "1"3"1I (6.4 mBq/l). The highest concentration of "1"3"1I (148 mBq/l) was detected in brand B whereas both "2"3"5U and "1"3"1I were not detected in brand C. All the values however were well below the new standard limits for individual radionuclides in milk established by the Japanese Ministry of Health, Labour and Welfare. This study indicates that the commercial milk brands assessed pose no radiation health threat to the consumers. (author)

Some aspects of geomagnetically conjugate phenomena

Energy Technology Data Exchange (ETDEWEB)

Rycroft, M.J.

1987-12-01

Both charged particles and waves convey information about the thermosphere, ionosphere and magnetosphere from the Northern to the Southern Hemisphere and vice versa, along geomagnetic flux tubes.The interhemispheric travel time of electrons or ions, being dependent upon L-value , pitch angle and energy (which may lie between less than or equal to 1 eV and greater than or equal to 1 MeV) may be many hours, ranging down to less than or equal to 1 s. However, the one-hop propagation time for magnetohydrodynamic or whistler mode waves generally lies between 10/sup 2/s and 1 s. Such times, therefore, give the time scales of transient phenomena that are geomagnetically conjugate and of changes in steady-state plasma processes occurring in geomagnetically conjugate regions. Contrasting examples are presented of conjugate physical phenomena, obtained using satellite, rocket, aircraft and ground-based observations; the latter capitalise upon the rather rare disposition of land - rather than ocean - at each end of a geophysically interesting flux tube. Particular attention is paid to the interactions between whistler mode waves and energetic electrons. Geomagnetic, radio, optical and plasma observations, taken together with model computations, provide a wealth of knowledge on conjugate phenomena and their dependence on conditions in the solar wind, substorms, L-value, etc... Finally, some suggestions are made for future lines of research.

Comparative cytotoxicity of gold-doxorubicin and InP-doxorubicin conjugates.

Science.gov (United States)

Zhang, Xuan; Chibli, Hicham; Kong, Dekun; Nadeau, Jay

2012-07-11

Direct comparisons of different types of nanoparticles for drug delivery have seldom been performed. In this study we compare the physical properties and cellular activity of doxorubicin (Dox) conjugates to gold nanoparticles (Au) and InP quantum dots of comparable diameter. Although the Au particles alone are non-toxic and InP is moderately toxic, Au-Dox is more effective than InP-Dox against the Dox-resistant B16 melanoma cell line. Light exposure does not augment the efficacy of InP-Dox, suggesting that conjugates are breaking down. Electron and confocal microscopy and atomic absorption spectroscopy reveal that over 60% of the Au-Dox conjugates reach the cell nucleus. In contrast, InP-Dox enters cell nuclei to a very limited extent, although liberated Dox from the conjugates does eventually reach the nucleus. These observations are attributed to faster Dox release from Au conjugates under endosomal conditions, greater aggregation of InP-Dox with cytoplasmic proteins, and adherence of InP to membranes. These findings have important implications for design of active drug-nanoparticle conjugates.

Radionuclides in plants in urban areas

International Nuclear Information System (INIS)

Todorovic, D.; Ajtic, J.; Popovic, D.; Nikolic, J.

2009-01-01

The results of a long-term study (from 2002 to 2008) on the concentrations of natural ( 7 Be, 210 Pb, 40 K) and fission ( 137 Cs) radionuclides in leaves of higher plants (linden and chestnut) in an urban area (city of Belgrade) are presented. The activity of the radionuclides was determined on an HPGe detector by standard gamma spectrometry. The study is a part of the ongoing air quality monitoring programme in urban areas in the Republic of Serbia. (author) [sr

Model for radionuclide transport in running waters

International Nuclear Information System (INIS)

Jonsson, Karin; Elert, Mark

2005-11-01

Two sites in Sweden are currently under investigation by SKB for their suitability as places for deep repository of radioactive waste, the Forsmark and Simpevarp/Laxemar area. As a part of the safety assessment, SKB has formulated a biosphere model with different sub-models for different parts of the ecosystem in order to be able to predict the dose to humans following a possible radionuclide discharge from a future deep repository. In this report, a new model concept describing radionuclide transport in streams is presented. The main difference from the previous model for running water used by SKB, where only dilution of the inflow of radionuclides was considered, is that the new model includes parameterizations also of the exchange processes present along the stream. This is done in order to be able to investigate the effect of the retention on the transport and to be able to estimate the resulting concentrations in the different parts of the system. The concentrations determined with this new model could later be used for order of magnitude predictions of the dose to humans. The presented model concept is divided in two parts, one hydraulic and one radionuclide transport model. The hydraulic model is used to determine the flow conditions in the stream channel and is based on the assumption of uniform flow and quasi-stationary conditions. The results from the hydraulic model are used in the radionuclide transport model where the concentration is determined in the different parts of the stream ecosystem. The exchange processes considered are exchange with the sediments due to diffusion, advective transport and sedimentation/resuspension and uptake of radionuclides in biota. Transport of both dissolved radionuclides and sorbed onto particulates is considered. Sorption kinetics in the stream water phase is implemented as the time scale of the residence time in the stream water probably is short in comparison to the time scale of the kinetic sorption. In the sediment

Model for radionuclide transport in running waters

Energy Technology Data Exchange (ETDEWEB)

Jonsson, Karin; Elert, Mark [Kemakta Konsult AB, Stockholm (Sweden)

2005-11-15

Two sites in Sweden are currently under investigation by SKB for their suitability as places for deep repository of radioactive waste, the Forsmark and Simpevarp/Laxemar area. As a part of the safety assessment, SKB has formulated a biosphere model with different sub-models for different parts of the ecosystem in order to be able to predict the dose to humans following a possible radionuclide discharge from a future deep repository. In this report, a new model concept describing radionuclide transport in streams is presented. The main difference from the previous model for running water used by SKB, where only dilution of the inflow of radionuclides was considered, is that the new model includes parameterizations also of the exchange processes present along the stream. This is done in order to be able to investigate the effect of the retention on the transport and to be able to estimate the resulting concentrations in the different parts of the system. The concentrations determined with this new model could later be used for order of magnitude predictions of the dose to humans. The presented model concept is divided in two parts, one hydraulic and one radionuclide transport model. The hydraulic model is used to determine the flow conditions in the stream channel and is based on the assumption of uniform flow and quasi-stationary conditions. The results from the hydraulic model are used in the radionuclide transport model where the concentration is determined in the different parts of the stream ecosystem. The exchange processes considered are exchange with the sediments due to diffusion, advective transport and sedimentation/resuspension and uptake of radionuclides in biota. Transport of both dissolved radionuclides and sorbed onto particulates is considered. Sorption kinetics in the stream water phase is implemented as the time scale of the residence time in the stream water probably is short in comparison to the time scale of the kinetic sorption. In the sediment

Synthesis and evaluation of the antioxidative potential of minoxidil-polyamine conjugates.

Science.gov (United States)

Hadjipavlou-Litina, Dimitra; Magoulas, George E; Bariamis, Stavros E; Tsimali, Zinovia; Avgoustakis, Konstantinos; Kontogiorgis, Christos A; Athanassopoulos, Constantinos M; Papaioannou, Dionissios

2013-07-01

A series of conjugates (MNX-CO-PA) of minoxidil (MNX) with the polyamines (PAs) putrescine (PUT), spermidine (SPD) and spermine (SPM) as well as dopamine were produced through activation of MNX with N,N'-carbonyldiimidazole, followed by reaction with dopamine or selectively protected PAs and acid-mediated deprotection. These conjugates together with conjugates of the general type MNX-PA or PA-MNX-PA, readily produced using literature protocols, were tested as antioxidants. The most potent inhibitors of lipid peroxidation were the conjugates MNX-SPM (2, 94%), SPM-MNX-SPM (4, 94%) and MNX-N(4)-SPD (7, 91%) and MNX (91%). The most powerful lipoxygenase (LOX) inhibitors were MNX (IC50 = 20 μM) and the conjugates MNX-N(8)-SPD (9, IC50 = 22.1 μM), MNX-CO-dopamine (11, IC50 = 28 μM) and MNX-N(1)-SPD (8, IC50 = 30 μM). The most interesting conjugates 2, MNX-CO-PUT (5), 8 and 11 as well as MNX were generally found to exhibit weaker (22-36.5%) or no (conjugate 8) anti-inflammatory activity than indomethacin (47%) with the exception of MNX which showed almost equal potency (49%) to indomethacin. The cytocompatibility of conjugates and MNX at the highest concentration of 100 μM showed a survival percentage of 87-107%, with the exception of conjugates with SPM (compound 2) and MNX-CO-SPM (6), which showed considerable cytotoxicity (survival percentage 8-14%). Molecular docking studies were carried on conjugate 9 and the parent compound MNX and were found to be in accordance with our experimental biological results. Copyright © 2013 Elsevier Masson SAS. All rights reserved.

Radionuclide getters in the near-field chemistry of repositories

International Nuclear Information System (INIS)

Holland, T.R.; Lee, D.J.

1991-06-01

The solubility of many radionuclides in a radwaste repository will be limited by the high pH of the cement based system. However, the inclusion of specific sorbing media, within the cement backfill, offers the ability to improve the retention of the more mobile radionuclides, such as caesium and iodine; thereby further reducing their environmental impact. This programme of work is intended to assess the radionuclide sorption efficiency of selected inorganic getters incorporated in cement. (author)

Anticancer activity of drug conjugates in head and neck cancer cells.

Science.gov (United States)

Majumdar, Debatosh; Rahman, Mohammad Aminur; Chen, Zhuo Georgia; Shin, Dong M

2016-06-01

Sexually transmitted oral cancer/head and neck cancer is increasing rapidly. Human papilloma virus (HPV) is playing a role in the pathogenesis of a subset of squamous cell carcinoma of head and neck (SCCHN). Paclitaxel is a widely used anticancer drug for breast, ovarian, testicular, cervical, non-small cell lung, head and neck cancer. However, it is water insoluble and orally inactive. We report the synthesis of water soluble nanosize conjugates of paclitaxel, branched PEG, and EGFR-targeting peptide by employing native chemical ligation. We performed a native chemical ligation between the N-hydroxy succinimide (NHS) ester of paclitaxel succinate and cysteine at pH 6.5 to give the cysteine-conjugated paclitaxel derivative. The thiol functionality of cysteine was activated and subsequently conjugated to multiarm thiol-PEG to obtain the paclitaxel branched PEG conjugate. Finally, we conjugated an EGFR-targeting peptide to obtain conjugates of paclitaxel, branched PEG, and EGFR-targeting peptide. These conjugates show anticancer activity against squamous cell carcinoma of head and neck cells (SCCHN, Tu212).

Small angle scattering from protein/sugar conjugates

Science.gov (United States)

Jackson, Andrew; White, John

2006-11-01

The Maillard reaction between free amine groups on proteins and sugars is well known. We have examined the effect of the reaction of the casein group of milk proteins with sugars on their nanoscale structure and aggregation. The small angle neutron scattering from beta casein and sodium caseinate and their sugar conjugates have been studied as a function of solution concentration. At high conjugate concentration (greater than ca. 5 mg/ml) the addition of sugar reduces supra-micellar aggregation of the protein whilst at lower concentration, where the protein is expected to be deaggregated already, little effect is seen. Guinier analysis of the scattering data show a radius of gyration of around 75 A˚ for beta casein in solution and around 80 A˚ for the sucrose conjugate.

Concentration of some radionuclides in some popular sudanese medicinal plants

International Nuclear Information System (INIS)

Sagiroun, M. I. A.