Abstract: In MR imaging of a predetermined volume segment of a living examination subject, the examination subject is stimulated with a defined stimulation pattern, MR data of the predetermined volume segment, are acquired, and MR images based on the MR data are generated that depend on the stimulation pattern. The predetermined volume segment is an internal organ or muscle tissue of the examination subject.

Abstract: A computer-implemented method for learning a tight frame includes acquiring undersampled k-space data over a time period using an interleaved process. An average of the undersampled k-space data is determined and a reference image is generated based on the average of the undersampled k-space data. Next, a tight frame operator is determined based on the reference image. Then, a reconstructed image data is generated from the undersampled k-space data via a sparse reconstruction which utilizes the tight frame operator.

Abstract: The present invention relates to the field of the protection of security documents and more particularly to a method and a device for determining the distribution and orientation of platelet-shaped pigment particles over an extended region of an optical effect layer (OEL). The method described herein comprises the steps of a) taking at least one image, under illumination of said extended region of the optical effect layer with collimated light incident from at least one first direction, of reflected light of said extended region of the optical effect layer from at least one second direction, using a telecentric lens-and-camera assembly having the optical axis of the telecentric lens oriented along said second direction, and b) processing the at least one image of said extended region to extract quantitative particle distribution and orientation information.

Abstract: A method of image reconstruction for a magnetic resonance imaging (MRI) system having a plurality of coils includes obtaining k-space scan data captured by the MRI system, the k-space scan data being representative of an undersampled region over time, determining a respective coil sensitivity profile for the region for each coil of the plurality of coils, and iteratively reconstructing dynamic images for the region from the k-space scan data via an optimization of a minimization problem. The minimization problem is based on the determined coil sensitivity profiles and redundant Haar wavelet transforms of the dynamic images.

Abstract: A method is described here for the layerwise construction of models, wherein, in a building region, a particulate material is applied layerwise and selectively cured. These steps are repeated until a desired model is obtained. The material comprises in this case a particulate building material and a spray-dried alkali metal silicate solution. Selective activation of the curing proceeds using a water-comprising solution.

Abstract: Security thread or stripe, magnetic orienting cylinder and methods making magnetic orienting cylinder and of using magnetic orienting cylinder. Security thread or strip includes a plastic foil having a hardened coating comprising magnetic or magnetizable pigment particles oriented to represent graphic information. Graphic information includes a seamless and continuous repetitive pattern having a repetition length.

Abstract: Disclosed is a device for the authentication of an optically variable entity exhibiting a color shift with changing viewing-angle, the device comprising a plate of light-refractive material, said plate having two surfaces and an array of light-refracting protrusions or recesses on at least one of said surfaces, and being disposed in said device such as to provide, aside each other, a direct view and a view through said plate onto at least parts of said optically variable entity, said view through said plate being an angularly deflected view, resulting from light refraction at said protrusions or recesses. Further disclosed is a method for authenticating an optically variable entity, as well as the use of a plate having two parallel surfaces and an array of positive or negative light-refracting protrusions or recesses on at least one of said surfaces for authenticating an optically variable entity.

Abstract: The present invention concerns a security thread or stripe for the incorporation into or onto a value-document or currency substrate, as well as a method and means of making such thread or stripe. The thread or stripe comprises a plastic foil which carries a hardened coating comprising oriented magnetic or magnetizable pigment particles, the orientation of said pigment particles representing graphic information. Preferred are optically variable magnetic or magnetizable pigment particles. Said hardened coating may also be comprised between a first and a second plastic foil. Said graphic information is a repetitive seamless pattern of suitable repetition length, which is produced using a magnetic orienting cylinder having a corresponding repetitive seamless magnetic field pattern. A magnetic orienting cylinder and a process for process for producing such magnetic orienting cylinder are also disclosed.

Abstract: A system and method for regression-based segmentation of the mitral valve in 2D+t cardiac magnetic resonance (CMR) slices is disclosed. The 2D+t CMR slices are acquired according to a mitral valve-specific acquisition protocol introduced herein. A set of mitral valve landmarks is detected in each 2D CMR slice and mitral valve contours are estimated in each 2D CMR slice based on the detected landmarks. A full mitral valve model is reconstructed from the mitral valve contours estimated in the 2D CMR slices using a trained regression model. Each 2D CMR slice may be a cine image acquired over a full cardiac cycle. In this case, the segmentation method reconstructs a patient-specific 4D dynamic mitral valve model from the 2D+t CMR image data.

Abstract: The present invention is related to a security element comprising, as an authentication and forgery-protection means, a 2-dimensional non-periodic, quasi-crystalline tiling, said tiling being embodied in the form of a material or a material modification in or on said element. The present invention is also related to a document comprising said security element, the use of said security element as an authentication and forgery-protection means for a document, as well as to a method protecting a document against forgery, comprising a step of embodying a 2-dimensional non-periodic, quasi-crystalline tiling, in the form of a material or a material modification in or on a security element comprised by said document.

Abstract: A computer-implemented method for reconstruction of a magnetic resonance image includes acquiring a first incomplete k-space data set comprising a plurality of first k-space lines spaced according to an acceleration factor and one or more calibration lines. A parallel imaging reconstruction technique is applied to the first incomplete k-space data to determine a plurality of second k-space lines not included in the first incomplete k-space data set, thereby yielding a second incomplete k-space data set. Then, the parallel imaging reconstruction technique is applied to the second incomplete k-space data to determine a plurality of third k-space lines not included in the second incomplete k-space data, thereby yielding a complete k-space data set.

Abstract: A computer-implemented method of selecting a Magnetic Resonance Imaging (MRI) sampling strategy includes selecting a base variable-density sampling pattern and determining a scan time associated with the base variable-density sampling pattern. A modified variable-density sampling pattern is created by modifying one or more parameters of the base variable-density sampling pattern to maximize a sampled k-space area without increasing the scan time. Next, a scan is performed on an object of interest using the modified variable-density sampling pattern to obtain a sparse MRI dataset. Then a sparse reconstruction process is applied to the sparse MRI dataset to yield an image of the object of interest.

Abstract: Paired optically variable security element which includes first and second optically variable thin-film multilayer interference devices in the form of optically variable foils or of printings made with inks having optically variable interference pigments. The first and second interference devices exhibit spectral matching at a determined angle of incidence. Sets of optically variable devices and of coating compositions include optically variable pigments for the production of the paired optically variable security element. Moreover, the security element can be used for the protection of documents and goods, and security documents and goods.

Abstract: A method of magnetic resonance (MR) imaging of a volume undergoing repetitive motion includes obtaining source slice data indicative of a plurality of source slices during the repetitive motion, and obtaining anchor slice data indicative of an anchor slice during the repetitive motion. The anchor slice intersects the plurality of source slices. The source slice data and the anchor slice data are reconstructed. A three-dimensional image assembly procedure is implemented to generate, for each phase of the repetitive motion, volume data based on a respective subset of the reconstructed source slice data. For each phase of the repetitive motion, the respective subset of slices is selected based on a correlation of the source slice data and the anchor slice data along an intersection between each source slice and the anchor slice. The source slice data of the selected subset is corrected for misalignment with the anchor slice data.

Abstract: Magnetic resonance imaging uses regularized SENSE reconstruction for a reduced field of view, but minimizes folding artifacts. A reference scan is oversampled relative to the reduced field of view. The oversampling provides coil sensitivity information for a region greater than the reduced field of view. The reconstruction of the object for the reduced field of view using the coil sensitivities for the larger region may have fewer folding artifacts.

Abstract: Disclosed is a document or article carrying information for the audible authentication of said document or article, wherein the information is present in or on said document or article in the form of a frequency-versus-time spectral density function (spectrogram), the spectrogram being embodied using document security means. Disclosed are further a method for producing said document or article; a reader device for displaying audible authentication information from said document or article, a method for authenticating said document or article and the use of a spectrogram for document authentication purposes.

Abstract: A method and system for automated view planning for cardiac magnetic resonance imaging (MRI) acquisition is disclosed. The method and system automatically generate a full scan prescription using a single 3D MRI volume. The left ventricle (LV) is segmented in the 3D MRI volume. Cardiac landmarks are detected in the automatically prescribed slices. A full scan prescription, including a short axis stack and 2-chamber, 3-chamber, and 4-chamber views, is automatically generated based on cardiac anchors provided by the segmented left ventricle and the detected cardiac landmarks in the 3D MRI volume.

Abstract: A method for image reconstruction includes receiving under-sampled k-space data, determining a data fidelity term of a first image of the under-sampled k-space data in view of a second image of the under-sampled k-space data, wherein a time component separated the first image and the second image, determining a spatial penalization on redundant Haar wavelet coefficients of the first image in view of the second image, and optimizing the first image according the data fidelity term and the spatial penalization, wherein the spatial penalization selectively penalizes temporal coefficients and an optimized image of the first image is output.

Abstract: A method to process medical image data has the following features. Immediately compressed raw data are acquired by an imaging medical technology apparatus. The compressed raw data are stored. In addition to the compressed raw data, processing data are stored which are provided to generate output data from the compressed raw data, wherein the file size of the compressed raw data and the processing data in total is less than the file size of the output data.

Abstract: A reconstructed image is rendered of a patient by a processor from a set of undersampled MRI data by first subtracting two repetitions of the acquired data in k-space to create a third dataset. The processor reconstructs the image by minimizing an objective function under a constraint related to the third dataset, wherein the objective function includes applying a Karhunen-Loeve Transform (KLT) to a temporal dimension of data. The objective function under the constraint is expressed as arg minf{??(f)?1 subject to ?Af?y?2??}. The reconstructed image is an angiogram which may be a 4D angiogram. The angiogram is used to diagnose a vascular disease.