Abstract: Chelating agents having in addition to their metal sequestering groups a functional group capable of reacting with bio-organic molecules are disclosed, in particular, substituted ethylenedinitrilotetraacetic acids such as 1-p-nitrophenylethylenedinitrilotetraacetic acid, 1-p-aminophenylethylenedinitrilotetraacetic acid and their derivatives are disclosed. These compounds are effective chelating agents and in addition are useful in the perturbed angular correlation method of studying molecular behavior.

Abstract: A carrier is disclosed for diagnostic scanning agents labelled with short-lived radioisotopes for medical organ studies which comprises colloidally dispersed phospholipid material, and also disclosed are new diagnostic scanning agents utilizing the carrier and a radioisotope, preferably .sup.99m Tc, which is in a form which complexes with the carrier. The radioisotope labelling can be carried out directly before use, the carrier in dispersed form being stable for a considerable period of time. Methods of preparation of the scanning agents are also disclosed which provide a material which localizes mainly in the liver after injection, or alternately at least initially in the lungs when an aggregating agent is used during preparation in a specific sequence of steps. Specific organ scans or sequential scanning is thus possible.

Abstract: A method is disclosed for determining the concentration of fission products in the reactor coolant of a liquid metal cooled nuclear reactor. Reactor coolant is bypassed at constant temperatures and constant velocity through a flow sampling system containing a sampling tube. After a period of time, the sampling tube is isolated and removed from the bypass system; the liquid metal coolant is removed from the tube; and, the radionuclides deposited on the sampling tube are measured by gamma spectroscopy. The concentration of fission products in the reactor coolant is then determined from the measured radioactivity of the deposited nuclides.

Abstract: A bone-seeking, technetium-99m-tin-phosphonate complex effective as a skeletal-imaging agent has been found particularly useful for diagnostic purposes. Skeletal tissue concentrations of technetium-99m obtained with the complex compare favorably to other bone-seeking radionuclides.

Abstract: Method and apparatus for continuously detecting cracks in aircraft blades while in flight. A hollow blade is sealed with a pressure differential, either above or below atmospheric. A reduction in the pressure differential such as results from cracks, is detected by a pressure sensor having a member which moves between a high pressure differential position and a low pressure differential position. A radiation source, typically a beta source, is carried on the member and moves from a shielded position to an unshielded position when the pressure differential drops. A radiation detector is mounted on a fixed portion of the aircraft and detects radiation from the source when the member moves to the unshielded position. The detector output may be used to operate a go-no go indicator providing a warning signal when the pressure differential falls below a predetermined value, or to operate an analog indicator providing an output varying as a function of the pressure differential.

Abstract: Radioactive iodine is detected in the effluent cooling gas from a nuclear reactor or nuclear facility by passing the effluent gas through a continuously moving adsorbent filter material which is then purged of noble gases and conveyed continuously to a detector of radioactivity. The purging operation has little or no effect upon the concentration of radioactive iodine which is adsorbed on the filter material.

Abstract: A diagnostic substance for cholescintigraphy which is formed by the reaction of pyridoxal and amino acids labelled with a radionuclide, in pyrogen-free water, the reaction product being adjusted to a pH of 8 to 9 and then autoclaved and cooled to produce a sterile, pyrogen-free non-antigenic solution for injection for biliary scanning.

Abstract: Method of determining the concentration of a substance in a solution which comprises the steps of incubating the solution with a known amount of radioactively labelled substance and a suspendable composite consisting of anti-substance antibody coupled chemically through an intermediate silane coupling agent to an inorganic carrier, the incubation period being for a time sufficient to form immunochemical complexes, separating the complexes from the solution, determining the radioactivity of either the separated complexes or the remaining solution, and relating that determination to a standard curve. Specific assays for digoxin, insulin, and estriol are disclosed.

Abstract: Technetium-99m-imido disphosphonate complex useful as a skeletal-imaging agent, particularly useful for diagnostic purposes.

Abstract: There is disclosed a process for the rapid identification of a microorganism and an apparatus for performing the method. The process comprises inoculating a number of different .sup.14 C labeled substrates with an unknown organism, at least some of said .sup.14 C labeled substrates being capable of being metabolized to .sup.14 CO.sub.2 by certain specific microorganisms. The substrates are incubated for a time sufficient to cause metabolic breakdown of at least some of said substrates resulting in the production of .sup.14 CO.sub.2 and analysis for radioactivity in the .sup.14 CO.sub.2 which is evolved from those substrates which are metabolized is performed to determine which substrates are metabolized and which substrates are not metabolized by the unknown microorganisms.

Abstract: An improved 99m-technetium labeled tin(II) colloid, size-stabilized for reticuloendothelial organ imaging without the use of macromolecular stabilizers and a packaged tin base reagent and an improved method for making it are disclosed.

Abstract: A radioimmunoassay method for the determination of triiodothyronine in human and animal fluids and tissues, particularly in serum. The method involves the separation of triiodothyronine from its binding proteins using a dextran gel column followed by competitive binding between the freed triiodothyronine and radioactive labeled triiodothyronine which remain bound to the gel column for triiodothyronine-specific anti-serum. Bound and free labeled triiodothyronine are separated by washing the column and their ratio is determined based on the amount of radioactivity remaining in the column to that originally added thereto.

Abstract: Metal hydroxides such as Fe(OH).sub.2, Fe(OH).sub.3 and Sn(OH).sub.2 are prepared in the form of spherical particles of uniform and controlled size suitable for tagging with a radioactive element such as technetium-99m. Aqueous suspensions of such tagged particles are useful in scintigraphy as lung scanning agents.

Abstract: A nuclear imaging system for mapping a spatially distributed source of high energy nuclear particles from a living organ which has selectively absorbed a radioactive compound in which the nuclear energy is spatially coded by a zone plate positioned between the source and a spatial detector, and a half tone screen is positioned between the source and the zone plate to increase the definition of the image.

Abstract: A method is described for determining the presence of an antigen-specific antibody in a vertebrate. Effluvial tissue is exposed to antigens from known sources and is subsequently examined to detect the presence or absence of a conjugate compound formed between a particular antigen and an antibody constituent of the tissue sample. The antigen may be labeled with a fluorescent or radioactive moiety to assist in the detection of conjugate compound formation.

Abstract: Compounds of formula (VIII) whereinR.sup.1, r.sup.2, r.sup.3, r.sup.4 and R.sup.5 are each selected from hydrogen and an hydroxyl group and at least four are hydrogen;B is an alkylene chain of from 1 to 4 carbon atoms;R is selected from hydrogen and an alkyl group of from 1 to 4 carbon atoms;A is selected from a bond and a straight or branched, optionally substituted alkylene chain of 1 to 6 carbon atoms, andX.sup.1 and X.sup.2 are each selected from hydrogen and an iodine radioisotope.Compounds of this formula are of value as agents for use in the radioimmunoassay of corresponding genins of formula (V) and derivatives thereof. Also provided by the invention are a radioimmunoassay method utilizing compounds of formula (VIII) and a test kit suitable for use in performing the assay.

Abstract: In order to measure the level of radioactivity of liquids in a set of vessels, e.g. those employed in a competitive radio-assay, liquid is drawn successively from each one of the set into a measuring region defined inter alia by radiation shielding, so as to fill the region, the measurement takes place in the region, and the liquid is thereafter expelled.

Abstract: This disclosure concerns a solid phase method for detecting antigens or antibodies. An unknown sample is contacted with two sources of solid phase antigen. By treating each source in a particular manner it is possible to determine if the sample contains antigen or antibody.

Abstract: A method for determining serum thyroxine (T-4) in which the T-4 is first separated from the serum by adsorption onto a montmorillonite clay and then competitively bound by exogenous thyroxine binding globulin in the presence of a known amount of radioactive T-4. The competitively bound serum T-4 and radioactive T-4 is separated from the unbound serum T-4 and radioactive T-4 by passage through an ion exchange resin column. The serum T-4 concentration is determined by measuring the amount of bound radioactive T-4 and referring to a standard curve.

Abstract: Disclosed is a well logging system for performing a continuous log of the oxygen and silicon content of earth formations in the vicinity of a well bore. A downhole sonde housing a pulsed source of 14 mev neutrons is used to irradiate earth formations in the vicinity of the well bore. A NaI (T1) detector spaced approximately 253/8 inches from the source detects gamma rays caused by neutron activation of elemental oxygen and silicon in the formations and produces voltage pulses representative of the elemental oxygen and silicon. The voltage pulses are transmitted to the surface where they are separated, corrected for background radiation and plotted continuously as a function of bore hole depth. The resultant well log traces may be interpreted in terms of lithology or formation water saturation by the use of disclosed techniques.

Abstract: Homogeneity of bulk control serum is determined when making production fills of clinical chemistry control serum using a radioactive tracer in the bulk control serum tank. A radioactive tracer is added to the control serum along with any other added constituents. After standard bottles are filled, they are analyzed for radioactivity in a radiation counter for measuring the amount of radioactive tracer in each bottle and thereby determining the homogeneity of the contents of the bottles.

Abstract: In vitro method for assessing thyroid function based on an indirect estimation of the free thyroxine concentration of a sample of serum. Known amounts of a sample of serum to be tested and a radioactive labeled thyroxine solution are added to an alkaline crosslinked dextran gel column which serves to dissociate the serum thyroxine bound to thyroxine binding proteins. After washing the serum proteins from the column, a portion of the mixture of labeled and serum thyroxine is eluted from the column using a known amount of the serum sample and a known amount of eluting liquid containing thyroxine binding protein. The use of a portion of the serum sample normalizes the elution of free thyroxine against the thyroxine binding capacity of the serum sample.

Abstract: A method for nondestructively determining the deuterium and tritium content of laser fusion targets by counting the x rays produced by the interaction of tritium beta particles with the walls of the microballoons used to contain the deuterium and tritium gas mixture under high pressure. The x rays provide a direct measure of the tritium content and a means for calculating the deuterium content using the initial known D-T ratio and the known deuterium and tritium diffusion rates.

Abstract: A method is disclosed whereby the amount of a lubricant composition such as a spin finish, coning oil, etc. applied to a textile strand may be accurately determined in a matter of seconds or minutes. The method involves applying to a running length textile strand a lubricant composition containing a tracer, winding the lubricated strand into a package, and subjecting the package to nondestructive analysis with an X-ray spectrochemical analyzer to measure the amount of tracer present in the package and to thereby obtain a measurement of the relative amount of lubricant applied to the strand.

Abstract: The present invention relates to a method for use in liquid scintillation measurements to feed an accurately determined amount of radioactive substance to a fluid scintillation system for a calibration measurement. According to the invention an accurately determined amount of radioactive substance is adsorbed to a carrier, which is introduced into the fluid scintillation system. The invention also relates to a carrier for use in the method.

Abstract: Method of determining the distance between an area under fire and the muzzle of the weapon by means of autoradiography of the irradiated firing residues on this area. Several carrier areas are fired at from various distances. The carrier areas are subsequently activated by neutron irradiation and subsequently contacted with a film sensitive to nuclear radiation. The series of autoradiographs produced after development on the film are compared with the autoradiograph, produced in the same way, of the firing trace to be investigated on the area fired at and used as a distance standard for that trace.

Abstract: A shutter assembly for a radioactivity measuring apparatus having a sample counting chamber, the assembly having a bulky solid lead cylinder with a sample access port extending therethrough for alignment with the sample chamber. The cylinder is rotated by a Geneva wheel arrangement having a drive wheel with a plurality of equi-angularly disposed pins perpendicular to the surface thereof engaging radially extending open-ended slots in a driven wheel secured to the lead cylinder for concurrent rotation therewith. The drive wheel is rotated at a constant speed with the driven wheel accelerating as a pin traverses the slot from the open end toward the driven wheel center and then decelerating as the pin traverses the reverse direction to provide precise positioning with adjacent pins engaging the open ends of adjacent slots in the stop position of the cylinder.

Abstract: A method for preparing a pyrophosphate-tin composition labelled with 99.sup.m technetium for medical diagnosis by scintigraphy, especially bone scintigraphy. A pyrophosphate solution and a freshly prepared stannous chloride solution are mixed together and then neutralized to a pH within the range of 5 to 7, the mixture is eventually lyophilized in order to obtain a pyrophosphate-tin complex in powder form which is then mixed with a solution containing 99.sup.m Tc, the last-mentioned final step of the method being carried out at the moment of use. The complex has a pyrophosphate-tin molecular ratio of at least 30.

Abstract: Particles, preferably substantially spherical particles having a smooth outer surface and essentially void-free interior are produced, consisting essentially of solid, cold-water insoluble vehicle comprising a physiologically acceptable, parenterally metabolizable protein or polysaccharide having dispersed therein a water-insoluble carrier loaded with radioisotopes, which are substantially non-leachable upon short term exposure to cold water. Such particles can be administered parenterally for diagnostic purposes, or for treatment with radioactive materials. On administration in this way, they are broken down or solubilized by the body fluids over a predeterminable period ranging from minutes to several days, whereupon the radioisotopic material is excreted from the body thus limiting exposure to the radiation.