Abstract: A system, method and computer program product for detecting indicators for structural changes of NMR active test molecules in a test sample, or indicators for structural changes of the environment of said test molecules in relation to a reference molecule. Initial local similarity values are obtained, using a similarity function and representing a local similarity between a reference spectrum and a test spectrum within corresponding similarity regions (SRR, SRT). The initial local similarity values represent a similarity map (SM1) in which contours of a first shape type are indicators (I1) for structural changes of the test molecule, and in which contours of a second shape type are indicators (I2) for structural changes of the environment of said test molecule in relation to the reference molecule.

Abstract: A method for determining an electric current includes sending the electric current to be measured through a shunt arrangement that includes at least three identical resistors. The at least three identical resistors are thermally coupled to a common base plate and are electrically interconnected such that the electric current is at least partially divided such that a first local current through a first resistor is not equal to a second local current through a second resistor. The method also includes measuring, at the shunt arrangement, a first voltage and a second voltage via which the voltage dropping across a first resistor and across a second resistor are directly or indirectly determinable, and determining the electric current via the first voltage and the second voltage. A heating in the shunt arrangement generated by the electric current is at least partially taken into account in the determining the electric current.

Abstract: An apparatus for collecting liquid fractions from a separation/reaction apparatus (1). A capillary (2) guides an extracted liquid fraction to a branching unit (3), a collection arrangement (4) carries a plurality of target vessels (5) receiving the liquid fraction from the capillary and a fluid line (6) is flow-connected to a fluid pump (7) and opens into the branching unit. The capillary and the fluid line each have outlet openings in the direct vicinity of one another at their end facing a target vessel such that liquid emerging from the outlet opening (2?) of the capillary transitions into the outlet opening (6?) of the fluid line. This precludes back mixing with earlier/later liquid fractions, precludes uncontrolled dripping of sample substance at the transfer point, speeds displacement of the target vessels in the collection arrangement, facilitates automation of the fraction processing procedure, and results in a more compact fraction collection apparatus.

Abstract: A method for generating a magnetic resonance image includes providing MR segment data records, wherein each MR segment data record has N×M frequency voxels in k-space. To reduce the acquisition time during MR segment recordings, the amount of MR data is reduced by incompletely sampling the k-space during a recording. The missing data of the MR segment data records are reconstructed twice: Preliminarily reconstructed MR segment data records are calculated first, with a reconstruction kernel obtained from reference data. Modified reference images containing phase information are obtained by creating phase images from the preliminarily reconstructed MR segment data records and combining these phase images with the absolute value of the reference image generated from the reference data. The second reconstruction kernels are ascertained therefrom in turn. In contrast to the first reconstruction kernel, these contain phase information, such that the missing data can be reconstructed without phase artifacts.

Abstract: An MAS probehead (1) positioned in a magnet bore (2) includes a sample chamber (3) with a stator (4) for receiving a rotor and an RF coil that radiates RF pulses into and/or receives RF signals from an NMR sample (5). A temperature-control apparatus guides gas at a first variable temperature T1 into the sample chamber and through the stator during an NMR measurement, and guides a pressurized gas stream at a second variable temperature T2 around the sample chamber. The sample chamber is surrounded by an encapsulation device (6), at least in the azimuthal direction around the axis of the magnet bore and counter to the flow direction of the pressurized gas, and is oriented to provide an air gap (7?) between the sample chamber and the magnet bore. This prevents dissipation of the gas temperature to outer parts of the probehead, and yields larger NMR measurement temperature ranges.

Abstract: Techniques for determining motion states of at least two bodies by an MR-device are provided, wherein the bodies each have a respective target region which is in an anatomic motion comprising a repetitive motion pattern with a motion repetition rate, and in particular, for cardiac and/or respiratory motion. A sequence of individual MR-measurements are performed on the bodies at a MR-repetition rate higher than the motion-repetition rate, wherein nuclear spins of the at least two bodies are excited during the sequence of individual MR-measurements either simultaneously or alternately at navigator times. With the individual MR-measurements, navigator signals are determined, each respective navigator signal indicative of the motion state of at least one of the motion patterns at the navigator time of the navigator signal. These techniques allow simultaneously determining motion states for imaging more than one body with a repetitive motion pattern with reduced preparation time.

Abstract: A closed cycle cryocooler is thermally connected to an elongated, cup-shaped sample well and cools down the sample well. Gaseous helium at a relatively low pressure is introduced into the sample well so that, as the sample well is cooled by the cryocooler, the gas in the sample well is also cooled. A sample is attached to a sample stick assembly which is then lowered into the sample well where the sample is cooled by the cooled gas to carryout experiments at low temperature. The sample stick assembly is mechanically attached to the spectrometer magnets and a flexible rubber bellows connects the sample stick assembly to the sample well so that vibration generated by the cryocooler is not transferred to the sample.

Abstract: The present invention relates to a dinitroxide biradical compound of general formula (I): In formula (I), A is a carbon, an ammonium, or a phosphonium; each of A1 to A6 is a single bond, O, N, N(O), S, S(O), SO2, C(O), or a (C1-C4) alkyl chain; and Z1 and Z2 are selected from R1 and R2 in combination, so that there is always at least one R2 group that is substituted with R3 group. In Z1 and Z2, R1 is an H, an aryl, or a heteroaryl; R2 is an alkyl chain, an alkenyl chain, an alkynyl chain, a cycloalkyl, a heterocycloalkyl, an aryl, or a heteroaryl; and R3 is an alkyl chain, an alkenyl chain, an alkynyl chain, a cycloalkyl, a heterocycloalkyl, an aryl, a heteroaryl, an ether, an ester, or an azide. When Z1 and Z2 are combined together with the same carbon atom of the nitroxide ring to which they are bonded, they form a spirocycloalkyl or a spiroheterocycloalkyl, the spirocycloalkyl or the spiroheterocycloalkyl being substituted with R3.

Abstract: A magnet arrangement having a hollow-cylindrical magnet element that has an axial length Lz,M and an inner radius Rin, is constructed from magnet segments arranged concentrically around the z-axis, and has a Halbach magnetization. At least one ring-shaped magnet element has a notched, hollow-cylindrical cutout extending circumferentially around the z-axis symmetrically with respect to the plane z=0, the axial extent Lz,A of the cutout being less than the axial length Lz,M of the magnet element. The cutout has a radial depth TA and an axial length Lz,A<Lz,M between the z-positions z=?zA to z=+zA. The radial depth TA and the axial length Lz,A of the cutout are to ensure that the remaining inhomogeneity of the homogenous magnetic field B0 in a predefined measurement volume having an axial plateau length LP in the center of the magnet arrangement does not exceed 10 ppm.

Abstract: A hybrid imaging apparatus includes a magnetic resonance imaging (MM) arrangement having an RF resonator structure (1) and a gradient coil system (8) having a longitudinal axis, an emission tomography (ET) arrangement with a detector device having at least one photosensor (3) and one circuit board arrangement with at least one readout circuit board (11) on which an ET electronics is arranged, and an internal shielding device (7) shielding the readout electronics (4) of the ET arrangement and shielding the RF resonator structure of the MRI arrangement. The photosensor is arranged, in relation to the longitudinal axis, radially inside the sensor circuit boards and radially outside the RF resonator structure. The internal shielding device is arranged radially outside the photosensor and/or integrated into the photosensor. This achieves both a compact design and optimized performance of the detection of the MR and ET imaging.

Abstract: A monitoring device is provided for analytical measurement of reaction fluid produced in a reaction vessel in a spectrometer with a monitoring cell. The distribution apparatus includes at least four supply and return lines that open into the distribution apparatus, wherein the distribution apparatus comprises a distribution device for distributing reaction fluid to the supply and return lines. The distribution apparatus comprises a distribution vessel in which the distribution device and an electrically controllable pump device for pumping of the reaction fluid are provided, wherein the distribution device comprises an electrically controllable valve device for distributing the reaction fluid to the lines that open into the distribution vessel.

Abstract: A system including an NMR spectrometer (1) with a flow cell (2) analyzing a first liquid test sample (P1), a distributing device (3) with a multi-way valve, plural assemblies interconnected via fluid lines through the distributing device, a cannula (5) taking test samples from a storage vessel (5a), a sample loop (6) temporarily storing a further test sample (P2), and a pump device (7) pumping liquid (S) into the system. The valve arrangement a) decouples the sample loop with the temporarily stored further test sample and, simultaneously, b) decouples the flow cell with the first test sample from all fluid lines to the distributing device; and c) connects the cannula to the pump device for a simultaneous purging step or to the flow cell for removing the first test sample into a receiving vessel (5b; 5c) or to the sample loop for receiving a subsequent test sample.

Abstract: A method for establishing and/or reducing artifacts that arise when reconstructing (R) an MPI overall image data record from MPI signal data and an appended system matrix (SMapp(r,f)), wherein the appended system matrix (SMapp(r,f)) includes system matrices of different particle classes (P1, P2). The method includes setting a selection region (cvn(r)) of a reconstructed MPI overall image data record (cn(r)), producing virtual signal data (sn(f)) by inverse transformation of the selection region, reconstructing a virtual overall image data record (c?vn(r)) from the virtual signal data and the appended system matrix, setting an artifact region (cartifact_n(r)) within the reconstructed virtual overall image data record so that the artifact region has only voxels lying outside of the selection region, and assigning the image data present in the artifact region as artifact image data (cartifact_n(r)). This permits ghost artifacts to be corrected.

Abstract: A method for establishing a local concentration distribution of magnetic particles of at least one particle class within an examination volume or a variable derived from this concentration distribution. The method includes providing at least one system matrix, providing MPI signal data of at least one sample including magnetic particles of at least one particle class within a measurement volume, and reconstructing spatially resolved MPI image data from the provided MPI signal data. At least one spatial projection of at least one part of the system matrix is carried out along a projection direction and a projected system matrix is generated thereby. The reconstruction of the MPI image data is implemented with the at least partly projected system matrix, as a result of which MPI image data of a spatial projection of the local concentration distribution of the magnetic particles are produced along the projection direction.

Abstract: An NMR probe head (1) having an RF coil arrangement (2a) in a coil region (2) and an RF shielding tube (3) for supply lines leading from a connection region (4) to the coil region. An elongated backbone (5) is arranged inside the shielding tube and has an inherently rigid, mechanically stiff structure having continuous bores and/or connecting channels (5a) which run parallel to the tube axis and accommodate the supply lines. The backbone has a continuously electrically conductive outer surface which leads from the connection region to the coil region and is electrically conductively connected to the conductive inner surface of the shielding tube via connecting elements (6). A continuous electrically conductive contour is formed thereby between the backbone and the shielding tube. This shields against externally incident RF fields and spatially separates the stable mechanical supporting construction and the supply lines from the electronic and RF components.

Abstract: A probe head (1) of an NMR-MAS assembly has a stator (2) with an opening (4) receiving a rotor (3) which, in a measuring position, rotates at the magic angle to the B0 field. The stator is pivotable between the measuring position and a loading position of the rotor. A detection device (5) permits external, contactless identification of whether the opening of the stator is fitted with a rotor. The detection device has a light source (5a), from which light is introduced into a lower end (6?) of a light guide (6). The stator has a first bore (2a), in which a first light guide stump (7a) is positioned such that, in the loading position of the stator, it produces an optical connection between a rotor inserted in the stator and an upper end (6?) of the light guide opposite the lower end.

Abstract: An EPR resonator for a cylindrical TE01n microwave mode, where n=1, 2, 3, or 4, has: a cylindrical body (10) which has an RF absorption of less than 5% at RFs below 1 kHz, a first plunger (11) delimiting the resonating volume within the body in an axial direction at a first end and a second plunger (12) delimiting the resonating volume within the body at a second end, the second plunger having an opening (13) for inserting an EPR sample. The first and second plunger each has a spiral winding of an electrically conductive filament wherein neither the ends nor neighboring turns of the spiral windings have electrically conductive connections prone to forming electrically closed loops. Using spiral winding plungers for cylindrical TE01n microwave modes provides equivalent functionality compared to conventional plungers, but without creating Eddy currents at frequencies lower than the frequency of the TE01n microwave mode.

Abstract: An NMR-MAS probehead having an MAS stator (3) receiving an MAS rotor (5) that is surrounded by an RF coil (4) and that has a sample substance, and having a first microwave guide (1) supplying microwave radiation into a sample volume (0) through a coil block (2). The coil block is constructed from dielectric material, is inserted into the wall of the MAS stator so that it surrounds the RF coil and the MAS rotor, and has a first bore (4?) that extends coaxially with the longitudinal axis of the elongate MAS rotor, the RF coil being fastened to the inner wall of said first bore, as well as a second bore (8?) that extends coaxially with the longitudinal axis of the first microwave guide and has a hollow, elongate second microwave guide (8) supplying microwave radiation from the first microwave guide into the sample volume.

Abstract: A magnet arrangement (1) having a permanent magnet system with at least two ring-shaped magnet elements (2) which are made of individual magnet segments (3), are arranged cylindrically symmetrically and stacked on one another in the z direction and/or concentrically, and arranged such that the magnetization directions of the individual segments in the rings extend parallel in an x-y plane. The magnet elements align relative to one another in the z direction and have a Halbach magnetization Before final mounting in the magnetic resonance apparatus, the magnet elements are prefabricated as solid structures and their respective magnet segments are fixed undisplaceably relative to one another. But the magnet elements are displaceable relative to one another in the x-y plane, and are mounted rotatably and/or tiltably relative to one another.

Abstract: Systems and methods for improved NMR signal detection are described. The system receives NMR signal data produced by a sample over time in response to an excitation pulse and selects a predefined system function for application to the NMR signal data for systematic variation of signal properties The system function has a different influence on NMR signal components than on noise components of the sampled signal and has a variation parameter to control the systematic variation. A plurality of variation parameter values is provided with differing values to influence broad NMR signals as well as weak NMR signals. The system generates for each variation parameter value a corresponding intermediate data set by applying the system function with the respective variation parameter value to the NMR signal data. Further, from each intermediate data set, a respective base value centered spectrum is generated in the frequency-domain.