Abstract: Presented herein are systems and methods for tomographic imaging of a region of interest in a subject using short-wave infrared light to provide for accurate reconstruction of absorption maps within the region of interest. The reconstructed absorption maps are representations of the spatial variation in tissue absorption within the region of interest. The reconstructed absorption maps can themselves be used to analyze anatomical properties and biological processes within the region of interest, and/or be used as input information about anatomical properties in order to facilitate data processing used to obtain images of the region of interest via other imaging modalities. For example, the reconstructed absorption maps may be incorporated into forward models that are used in tomographic reconstruction processing in fluorescence and other contrast-based tomographic imaging modalities.

Abstract: A method and system for acquiring scan data. The system includes a processing device and an imaging device. The processing device is configured to generate a target protocol group corresponding to a plurality of target bed positions by adjusting, based on a reference image, at least one parameter of an initial protocol group. The target protocol group includes a target general protocol for localizing the plurality of target bed positions and a plurality of target primary protocols for localizing each of the plurality of target bed positions. The imaging device is configured to acquire scan data by scanning the object based on the target protocol group.

Abstract: A system and method can determine one or more CT scanner calibration parameters from a plurality of calibration object projections in a plurality of radiographs.

Abstract: An image processing apparatus includes a processor programmed to obtain a first radiation image of a subject captured from a first direction, obtain a second radiation image of the subject captured from a second direction that intersects the first direction, and either correct one of the first radiation image and the second radiation image based on positional information of a device for capturing the one of the first radiation image and the second radiation image, or correct another one of the first radiation image and the second radiation image based on information on a position of a specific region of the subject obtained from the one of the first radiation image and the second radiation image.

Abstract: A fixture for fabricating a detector mini-module includes a lower block having a Y-datum lower block upper surface, an X-datum lower block surface, and a Z-datum lower block surface orthogonal to both the Y-datum lower and X-datum block surface surfaces. A mount block for a detector is positionable and in contact with the X-datum lower block surface, the Y-datum lower block upper surface, and the Z-datum lower block surface. An intermediate block is positionable on the lower block having an aperture passing through an upper surface and having an X-datum intermediate block surface and a Z-datum intermediate block surface. When a mount block for the detector mini-module is positioned on the lower block, the mount block is biased having an X-axis mount block planar surface aligned with the X-datum lower block surface, and biased having a Z-axis mount block planar surface aligned with the Z-datum lower block surface.

Abstract: A medical image diagnosis apparatus according to an embodiment includes: a first supporting part, a second supporting part, and one or more columns. The first supporting part is configured to support an imaging system related to imaging a subject to be examined. The second supporting part is configured to support the first supporting part from underneath the first supporting part. The one or more columns are configured to support the second supporting part so as to be movable along a vertical direction.

Abstract: A method for generating result slice images with at least partially different slice thickness based on a tomosynthesis image data set of a breast includes generating average value slices and maximum value slices (MIP) based on the tomosynthesis image data set, frequency dividing the average value slices into low-pass filtered and high-pass filtered average value slices, high-pass filtering of maximum value slices to form high-pass filtered maximum value slices, mixing high-pass filtered maximum value slices and high-pass filtered average value slices to form mixed high-pass filtered maximum value slices, combining the low-pass filtered average value slices with the mixed high-pass filtered maximum value slices to form the result slice images, and applying a moving maximum value across a selected thickness of maximum value slices or across a selected thickness of mixed high-pass filtered maximum value slices.

Abstract: A computer-tomography (CT) imaging system, comprising an imaging data acquisition system. The imaging data acquisition system includes a plurality of sets of a detector section, a storage section, and an aggregation section. The detector section includes a plurality of detector elements each being configured to convert radiation into electric signals. The aggregation section is configured to aggregate imaging data carried by the electronic signals from the detector section. The storage section is connected with an output of the detector section and an input of the aggregation section. The storage section comprises a predetermined number of non-volatile memories to store the imaging data from the corresponding detector elements.

Abstract: A nuclear medicine tomography system including: a detector carrier; a detector carrier housing including an inner space; a plurality of detector units, coupled to the detector carrier, each detector unit comprising: a detector camera; a cooling channel which guides air to the detector camera from the inner space; an exhaust channel which guides air from the detector camera to the inner space; a heat pump configured to cool air within the inner space.

Abstract: A method of radiation therapy comprises, while a gantry of a radiation therapy system rotates continuously in a first direction through a treatment arc from a first treatment delivery position to a second treatment delivery position, causing an imaging X-ray source mounted on the gantry to direct X-rays through a target volume and receiving a set of X-ray projection images from an X-ray imager mounted on the gantry; determining a current location of the target volume based on the set of X-ray projection images; and while the gantry to continues to rotate to the second treatment delivery position, initiating delivery of a treatment beam of a treatment-delivering X-ray source mounted on the gantry to the target volume, and continuing to cause the gantry to rotate in the first direction from the second treatment delivery position to a third treatment delivery position.

Abstract: The disclosed apparatus, systems and methods relate to a framelet-based iterative algorithm for polychromatic CT which can reconstruct two components using a single scan. The algorithm can have various steps including a scaled-gradient descent step of constant or variant step sizes; a non-negativity step; a soft thresholding step; and a color reconstruction step.

Abstract: Positron emission tomography (PET) with partially known attenuation accounts for the missing attenuation. Since a computed tomography (CT) scan may provide attenuation for less than all the locations used in PET reconstruction, artificial intelligence corrects for the missing attenuation. For example, the unknown attenuation or attenuation correction factors are estimated by the artificial intelligence. The known and estimated attenuations or correction factors are used in the PET reconstruction, providing more uniform PET sensitivity and better accounting for scatter. As another example, the artificial intelligence alters intensity of the activity in some locations to account for reconstruction with missing attenuation information, correcting for sensitivity variation and/or lack of scatter information for some locations.

Abstract: Various methods and systems are provided for stationary CT imaging. In one embodiment, an imaging system comprises a stationary distributed x-ray source unit comprising a plurality of emitters positioned to emit x-ray beams through the imaging volume, one or more detector arrays extending around at least a portion of an imaging volume, each detector array comprising a plurality of detector elements, each detector element configured to receive x-ray beams from more than one emitter, and an anti-scatter device configured to be positioned between one or more emitters of the plurality of emitters and an object in the imaging volume.

Abstract: A method for determining a correction profile of an imaging device may include obtaining first data relating to the imaging device; comparing the first data and a first condition; obtaining, based on the comparison, a first correction profile relating to the imaging device; and calibrating, based on the first correction profile, the imaging device.

Abstract: A multi-axis imaging system comprising an imaging gantry with an imaging axis extending through a bore of the imaging gantry, a support column that supports the imaging gantry on one side of the gantry in a cantilevered manner, and a base that supports the imaging gantry and the support column. The imaging system including a first drive mechanism that translates the gantry in a vertical direction relative to the support column and the base, a second drive mechanism that rotates the gantry with respect to the support column between a first orientation where the imaging axis of the imaging gantry extends in a vertical direction parallel to the support column and a second orientation where the imaging axis of the gantry extends in a horizontal direction parallel with the base, and a third drive mechanism that translates the support column and the gantry in a horizontal direction along the base.

Abstract: A rotary-transmission-target microfocus X-ray source and an X-ray generation method based on the rotary-transmission-target microfocus X-ray source are provided. The X-ray source comprises a chamber, and an electron beam system is installed in the chamber. The electron beam system is arranged on a same side as an anode target rotating shaft. A motor in a rotary anode target system drives an anode target to rotate through a bevel gear transmission device. The microstructure of a target is designed. An electron beam emitted by the electron beam system vertically bombards the metal target of the rotating anode target. A cooling system is configured to cool the anode target.

Abstract: Systems and methods are provided for computed tomography (CT) imaging. In one embodiment, a method comprises adaptively blending at least two input image volumes with different spatially-variant noise characteristics to generate an output image volume with uniform noise throughout the output image volume. In this way, images may be reconstructed from projection data with data redundancy without introducing image artifacts from stitching images or variance in image noise due to the data redundancy.

Abstract: A computer-implemented method is for determining at least one main acquisition parameter determining a dose of x-rays to be emitted from an x-ray emitter during image acquisition using an x-ray emitter and an x-ray detector. A first image data of a first preparatory image is evaluated to determine if a repeat condition is fulfilled and/or to determine the main acquisition parameter and/or at least one second preparatory acquisition parameter. The first preparatory image is acquired by the x-ray detector using at least one first preparatory acquisition parameter to control the x-ray emitter. In all cases or when the repeat condition is fulfilled, the main acquisition parameter is determined depending on second image data of a second preparatory image, acquired by the x-ray detector after the first preparatory image while at least one second preparatory acquisition parameter is used to control the x-ray emitter.

Abstract: An exemplary focused tomography system comprises an x-ray transmitter that is configured to emit a radiation beam and an x-ray detector that is configured to detect incident radiation from the radiation beam. The system further includes an adaptive collimator device arranged between the x-ray transmitter and the x-ray detector and a controller device connected to the x-ray transmitter that is configured to cause the x-ray transmitter to emit the radiation beam at a first radiation dosage level when a path of the radiation beam intersects a region of interest of the subject and cause the x-ray transmitter to emit the radiation beam at a second radiation dosage level when the path of the radiation beam does not intersect the region of interest of the subject, such that the second radiation dosage level is less than the first radiation dosage level. Data within the region of interest can be reconstructed with image quality equivalent to traditional computed tomography scans.

Abstract: An imaging apparatus comprises a rotatable gantry system positioned at least partially around a patient support; a first source of radiation coupled to the rotatable gantry system, the first source of radiation configured for imaging radiation; a second source of radiation coupled to the rotatable gantry system; and a first radiation detector coupled to the rotatable gantry system and laterally movable relative to a central beam of the first source of radiation to receive radiation from at least the first source of radiation over various fields of view. Alternative configurations of the imaging apparatus and methods of using the imaging apparatus are also provided.

Abstract: A LIDAR system or a vehicle may include at least one processor configured to perform a method to detect objects in a field of view. The method may include controlling at least one LIDAR light source in a manner enabling light flux of the at least one LIDAR light source to vary over a plurality of scans of a field of view; receiving, from a group of detectors, a plurality of input signals indicative of reflections of light projected from the field of view; detecting a possible existence of an object in the background area based on first input signals associated with a first scanning cycle; detecting a possible existence of the object based on second input signals associated with a second scanning cycle; and aggregating the first and second input signals to detect an existence of the object at an object-existence-certainty level higher than a threshold.

Abstract: A real-time inline digital tomosynthesis system according to an embodiment of the present disclosure includes a subject moving rail configured to move a subject in a preset direction and at a preset speed, a pair of an X-ray generator and an X-ray detector fixedly provided to face each other in a first direction of the subject moving rail, a subject position identifier configured to identify and notify a current position of the subject based on an image or a sensor, and an image reconstructor configured to obtain a plurality of X-ray images having different subject positions through the X-ray detector based on the current position of the subject, and then reconstruct and output the plurality of X-ray images as at least one of a tomographic image for each section and one three-dimensional (3D) image.

Abstract: A system and method for improved image acquisition of multiple pulsed X-ray source-in-motion tomosynthesis imaging apparatus by generating the electrocardiogram (ECG) waveform data using an ECG device. Once a representative cardiac cycle is determined, system will acquire images only at rest period of heart beat. Real time ECG waveform is used as ECG synchronization for image improvement. The imaging apparatus avoids ECG peak pulse for better chest, lung and breast imaging under influence of cardiac periodical motion. As a result, smoother data acquisition, much higher data quality can be achieved. The multiple pulsed X-ray source-in-motion tomosynthesis machine is with distributed multiple X-ray sources that is spanned at wide scan angle. At rest period of one heartbeat, multiple X-ray exposures are acquired from X-ray sources at different angles. The machine itself has capability to acquire as many as 60 actual projection images within about two seconds.

Abstract: The disclosure herein relates to systems, methods, and devices for medical image analysis, diagnosis, risk stratification, decision making and/or disease tracking. In some embodiments, the systems, devices, and methods described herein are configured to analyze non-invasive medical images of a subject to automatically and/or dynamically identify one or more features, such as plaque and vessels, and/or derive one or more quantified plaque parameters, such as radiodensity, radiodensity composition, volume, radiodensity heterogeneity, geometry, location, and/or the like. In some embodiments, the systems, devices, and methods described herein are further configured to generate one or more assessments of plaque-based diseases from raw medical images using one or more of the identified features and/or quantified parameters.

Abstract: A deep-learning-based method for metal artifact reduction in CT images includes providing a dataset and a cGAN. The dataset includes CT image pairs, randomly partitioned into a training set, a validation set, and a testing set. Each Pre-CT and Post-CT image pairs is respectively acquired in a region before and after an implant is implanted. The Pre-CT and Post-CT images of each pair are artifact-free CT and artifact-affected CT images, respectively. The cGAN is conditioned on the Post-CT images, includes a generator and a discriminator that operably compete with each other, and is characterized with a training objective that is a sum of an adversarial loss and a reconstruction loss. The method also includes training the cGAN with the dataset; inputting the post-operatively acquired CT image to the trained cGAN; and generating an artifact-corrected image by the trained cGAN, where metal artifacts are removed in the artifact-corrected image.

Abstract: A system and method for image correction is provided. The method includes: receiving an original image; obtaining an image relating to a region of interest (ROI); detecting an artifact in the image relating to the ROI; generating an artifact image based on the artifact; and correcting the original image based on the artifact image.

Abstract: A method for estimating motion of an X-ray focal spot is provided. The acts of the method include acquiring image data by causing X-rays to be emitted from the X-ray focal spot of an X-ray source toward a radiation detector comprising multiple channels, wherein a subset of the channels each have a collimator blade positioned above the respective channel. The acts of the method also include independently estimating X-ray focal spot motion in an X-direction for the X-ray focal spot relative to an isocenter of the radiation detector and in a Y-direction along a direction of the X-rays for the X-ray focal spot relative to the isocenter based on respective channel gains for a first channel and a second channel of the subset of the channels.

Abstract: The various examples of the present disclosure are directed towards systems and methods for diagnosing brain health. An exemplary system includes a microscope, a processor, and a memory. The microscope outputs image data of a cornea of a patient. The memory has a plurality of stored code sections, which, when executed by the processor, include instructions for analyzing cornea image data to determine brain health. The instructions begin with receiving cornea image data from the microscope. The instructions then provide for determining at least one marker from the received cornea image data. The instructions then provide for outputting a brain health diagnosis based on the at least one marker.

Abstract: A system and method for determining stenosis severity in a subject's vasculature using multi-energy computer tomography (MECT) imaging is provided. In some aspects, the method includes acquiring MECT data using a CT system, performing a material decomposition process on acquired MECT data to generate one or more material density maps, and selecting, using the one or more material density maps, one or more regions of interest (ROIs) encompassing at least one vessel cross-section. The method also includes measuring an iodine content in the one or more ROIs, and determining a stenosis severity based on the measured iodine content. The method further includes generating a report indicating the stenosis severity associated with the subject's vasculature.

Abstract: Operational metrics of a distributed collection of servers in a cloud environment are analyzed by a service to intelligently machine learn which operational metric is highly correlated to incidents or failures in the cloud environment. To do so, metric values of the operational metrics are analyzed over time by the service to check whether the operation metrics exceed a particular metric threshold. If so, the service also checks whether such spikes in the operation metric above the metric thresholds occurred during known cloud incidents. Statistics are calculated reflecting the number of times the operational metrics spiked during times of cloud incidents and spiked during times without cloud incidents. Correlation scores based on these statistics are calculated and used to select the correlated operational metrics that are most correlated to cloud failures.

Abstract: A method and apparatus for removing breathing motion artifacts in imaging CT scans is disclosed. The method acquires raw imaging data from a CT scanner, and processes the raw CT imaging data by removing motion-induced artifacts via a motion model. Processing the imaging data may be achieved by initially estimating a 3D image to provide an estimate of raw sinogram image data, comparing the estimate to an actual CT sinogram, determining a difference between the sinograms, and iteratively reconstructing the 3D image by using the difference to alter the 3D image until the sinograms agree, wherein the 3D image moves according to the motion model.

Abstract: A method for image reconstruction may include obtaining projection data D0 generated by an imaging device by scanning an object at first angles, wherein the first angles may be a subset of second angles. The second angles may include at least short-scan angles for a system to conduct image reconstruction. The method may also include generating an image F1 based on the projection data D0. The method may also include determining, based on the image F1, projection data D1 corresponding to third angles that are a subset of the second angles and different from the first angles. The method may also include generating a final image associated with the object by performing an iteration process including one or more iterations using initial data including the image F1, the projection data D0, and the projection data D1.

Abstract: Training a CNN with pseudo ground truth for CT artifact reduction is described. An estimated ground truth apparatus is configured to generate an estimated ground truth image based, at least in part, on an initial CT image that includes an artifact. Feature addition circuitry is configured to add a respective feature to each of a number, N, copies of the estimated ground truth image to create the number, N, initial training images. A computed tomography (CT) simulation circuitry is configured to generate a plurality of simulated training CT images based, at least in part, on at least some of the N initial training images. An artifact reduction circuitry is configured to generate a plurality of input training CT images based, at least in part, on the simulated training CT images. A CNN training circuitry is configured to train the CNN based, at least in part, on the input training CT images and based, at least in part, on the initial training images.

Abstract: The present disclosure relates to systems and methods for image generation. The methods may include obtaining projection data generated by a scanner; generating, based on a first weighting function, a first image by back-projecting the projection data, the first image having a first region corresponding to a first part of the object; generating, based on a second weighting function, a second image by back-projecting the projection data, the second image having a second region corresponding to the first part of the object, the second region of the second image presenting a better CT number uniformity than the first region of the first image; and generating a third image based on the first image and the second image.

Abstract: Systems and methods for improving soft tissue contrast, characterizing tissue, classifying phenotype, stratifying risk, and performing multi-scale modeling aided by multiple energy or contrast excitation and evaluation are provided. The systems and methods can include single and multi-phase acquisitions and broad and local spectrum imaging to assess atherosclerotic plaque tissues in the vessel wall and perivascular space.

Abstract: Provided herein are devices and methods generating a panoramic rendering of a subject's teeth. Methods and processes are provided to image the subject's teeth with a dental scan. Methods and processes are also provided to automatically 3D render the subject's teeth with the scan images. Methods and apparatuses are also provided to generate simulated panoramic views of the subject's dentition from various perspectives.

Abstract: Systems and method for performing X-ray computed tomography (CT) that can improve spectral separation and decrease motion artifacts without increasing radiation dose are provided. The systems and method can be used with either a kVp-switching source or a single-kVp source. When used with a kVp-switching source, an absorption grating and a filter grating can be disposed between the X-ray source and the sample to be imaged. Relative motion of the filter and absorption gratings can by synchronized to the kVp switching frequency of the X-ray source. When used with a single-kVp source, a combination of absorption and filter gratings can be used and can be driven in an oscillation movement that is optimized for a single-kVp X-ray source. With a single-kVp source, the absorption grating can also be omitted and the filter grating can remain stationary.

Abstract: Systems and methods are provided for reprojection and back projection of objects of interest via homographic transforms, and particularly one-dimensional homographic transforms. In one example, a method may include acquiring imaging data corresponding to a plurality of divergent X-rays, assigning a single functional form to the plurality of divergent X-rays, determining, via a homographic transform, weights of interaction between a plurality of distribution samples and a plurality of X-ray detector bins based on the single functional form, and reconstructing an image based on the weights of interaction.

Abstract: Various embodiments include a method for facilitating tomographic reconstruction comprising: emitting an x-ray beam from an x-ray unit; ascertaining an attenuation of the x-ray beam during transmission through an object situated in a beam path of the x-ray beam; ascertaining structure data of the object based at least in part on the attenuation of the x-ray beam; and ascertaining a pose of the x-ray unit relative to the object using a digital model of the object and based at least in part on the attenuation of the x-ray beam.

Abstract: A medical scan assisted review system is operable to receive, via a network, a medical scan for review. Abnormality data is generated by identifying a plurality of abnormalities in the medical scan by utilizing a computer vision model that is trained on a plurality of training medical scans. The abnormality data includes location data and classification data for each of the plurality of abnormalities. Text describing each of the plurality of abnormalities is generated based on the abnormality data. The abnormality data and the text is transmitted to a client device. A display device associated with the client device displays the abnormality data in conjunction with the medical scan via an interactive interface, and the display device further displays the text via the interactive interface.

Abstract: An imaging system, such as a DBT system, capable of providing an operator of the system with information concerning the location, magnitude and direction of motion detected by the system during performance of the scan to enhance image processing. The imaging system provides the motion information to the operator directly in conjunction with the images processed by the imaging system thereby providing the operator with sufficient information for decisions regarding the need for additional images for completing the scan with the imaging system before the patient is discharged, or even before the breast is decompressed.

Abstract: A method and a system for providing calibration for a polychromatic photon counting detector forward counting model. Measurements with multiple materials and known path lengths are used to calibrate the photon counting detector counting response of the forward model. The flux independent weighted bin response function is estimated using the expectation maximization method, and then used to estimate the pileup correction terms at plural tube voltage settings for each detector pixel. The beam hardening corrections are then applied to the measured projection data sinogram, and the corrected sinogram is reconstructed to the counting image at the selected single energy.

Abstract: Systems and methods for packet payload mapping for robust transmission of data are described. For example, methods may include receiving, using a network interface, packets that each respectively include a primary frame and one or more preceding frames from the sequence of frames of data that are separated from the primary frame in the sequence of frames by a respective multiple of a stride parameter; storing the frames of the packets in a buffer with entries that each hold the primary frame and the one or more preceding frames of a packet; reading a first frame from the buffer as the primary frame from one of the entries; determining that a packet with a primary frame that is a next frame in the sequence has been lost; and, responsive to the determination, reading the next frame from the buffer as a preceding frame from one of the entries.

Abstract: An x-ray microscopy method that obtains a classification of different particles by distinguishing between different material phases through a combination of image processing involving morphological edge enhancement and possibly resolved absorption contrast differences between the phases along with optional wavelet filtering.

Abstract: A rotary joint includes a first part and a second part configured to rotate around a rotation axis against the first part. The first part has a first magnetic core and a capacitive data link component. The second part has a second magnetic core for coupling power with the a first magnetic core and a second capacitive data link component to transfer data from and/or to the first capacitive data link component. To weaken magnetic stray fields from the magnetic core, a resonant shield is provided outside the airgap between the magnetic cores. The resonant shield comprises an open ring-shaped structure, having two open ends which are connected by a capacitor to form a resonant circuit.

Abstract: A security inspection system and a method of configuring a security inspection device are provided. In an embodiment, the security inspection system may include: an identity information entry device configured to enter an identification of an inspected person; a parameter determination device configured to determine a parameter for performing a security inspection on the inspected person based on a security factor of the inspected person determined according to user data corresponding to the identification of the inspected person; and a security inspection device configured to perform the security inspection on the inspected person based on the determined parameter. According to embodiments, it is possible to accurately predict the user's behavior and evaluate the risk or potential danger from the user by analyzing and mining the user's comprehensive data, and thus to provide a more accurate security inspection solution.

Abstract: Described herein are systems and methods for performing plural-plane narrow-beam computed tomography.

Abstract: Supervised and unsupervised learning schemes may be used to automatically label medical images for use in deep learning applications. Large labeled datasets may be generated from a small initial training set using an iterative snowball sampling scheme. A machine learning powered automatic organ classifier for imaging datasets, such as CT datasets, with a deep convolutional neural network (CNN) followed by an organ dose calculation is also provided. This technique can be used for patient-specific organ dose estimation since the locations and sizes of organs for each patient can be calculated independently.

Abstract: A method for implementing a dynamic three-dimensional lung map view for navigating a probe inside a patient's lungs includes loading a navigation plan into a navigation system, the navigation plan including a planned pathway shown in a 3D model generated from a plurality of CT images, inserting the probe into a patient's airways, registering a sensed location of the probe with the planned pathway, selecting a target in the navigation plan, presenting a view of the 3D model showing the planned pathway and indicating the sensed location of the probe, navigating the probe through the airways of the patient's lungs toward the target, iteratively adjusting the presented view of the 3D model showing the planned pathway based on the sensed location of the probe, and updating the presented view by removing at least a part of an object forming part of the 3D model.

Abstract: A multi-axis imaging system comprising an imaging gantry with an imaging axis extending through a bore of the imaging gantry, a support column that supports the imaging gantry on one side of the gantry in a cantilevered manner, and a base that supports the imaging gantry and the support column. The imaging system including a first drive mechanism that translates the gantry in a vertical direction relative to the support column and the base, a second drive mechanism that rotates the gantry with respect to the support column between a first orientation where the imaging axis of the imaging gantry extends in a vertical direction parallel to the support column and a second orientation where the imaging axis of the gantry extends in a horizontal direction parallel with the base, and a third drive mechanism that translates the support column and the gantry in a horizontal direction along the base.