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https://www.readbyqxmd.com/read/28106129/retooling-laser-speckle-contrast-analysis-algorithm-to-enhance-non-invasive-high-resolution-laser-speckle-functional-imaging-of-cutaneous-microcirculation
#1
Surya C Gnyawali, Kevin Blum, Durba Pal, Subhadip Ghatak, Savita Khanna, Sashwati Roy, Chandan K Sen
Cutaneous microvasculopathy complicates wound healing. Functional assessment of gated individual dermal microvessels is therefore of outstanding interest. Functional performance of laser speckle contrast imaging (LSCI) systems is compromised by motion artefacts. To address such weakness, post-processing of stacked images is reported. We report the first post-processing of binary raw data from a high-resolution LSCI camera. Sharp images of low-flowing microvessels were enabled by introducing inverse variance in conjunction with speckle contrast in Matlab-based program code...
January 20, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28105559/mature-cystic-teratoma-of-the-ovary-a-cutting-edge-overview-on-imaging-features
#2
REVIEW
Hilal Sahin, Samir Abdullazade, Muzaffer Sanci
Mature cystic teratoma (MCT) is the most common neoplasm of the ovary and includes at least two well- differentiated germ cell layers. Different combinations of mature tissue derivatives with varying arrangements in the tumour cause a wide spectrum of radiological presentation ranging from a purely cystic mass to a complex cystic mass with a considerable solid component. In different imaging modalities, each radiological feature reflects a specific pathologic equivalent that forms because of diverse compositions of histological components...
January 19, 2017: Insights Into Imaging
https://www.readbyqxmd.com/read/28103553/data-driven-affine-deformation-estimation-and-correction-in-cone-beam-computed-tomography
#3
Vincent Van Nieuwenhove, Jan De Beenhouwer, Thomas De Schryver, Luc Van Hoorebeke, Jan Sijbers
In Computed Tomography (CT), motion and deformation during the acquisition lead to streak artefacts and blurring in the reconstructed images. To remedy these artefacts, we introduce an efficient algorithm to estimate and correct for global affine deformations directly on the cone beam projections. The proposed technique is data-driven and thus removes the need for markers and/or a tracking system. A relationship between affine transformations and the cone beam transform is proven and used to correct the projections...
January 16, 2017: IEEE Transactions on Image Processing: a Publication of the IEEE Signal Processing Society
https://www.readbyqxmd.com/read/28098171/metallurgical-investigation-on-fourth-century-bce-silver-jewellery-of-two-hoards-from-samaria
#4
D Ashkenazi, H Gitler, A Stern, O Tal
A fourth century BCE silver jewellery collection, which is part of two hoards of Samarian coins (the Samaria and Nablus Hoards), was studied by non-destructive analyses. The collection, which consists of pendants, rings, beads and earrings, had been examined by visual testing, multi-focal microscopy and SEM-EDS analysis. In order to enhance our knowledge of past technologies of silver jewellery production, we developed a metallurgical methodology based on the chemical composition of the joints and bulk. The results show that all artefacts are made of silver containing a small percentage of copper...
January 18, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28094855/technical-note-dose-distributions-in-the-vicinity-of-high-density-implants-using-3d-gel-dosimeters
#5
Andre Asena, Shaun Thomas Smith, Tanya Kairn, Scott Bradley Crowe, Kazuyuki Hosokawa, Steven Sylvander, Jamie Vincent Trapp
PURPOSE: In this work, we develop a methodology for using Fricke gel dosimeters for dose distribution measurements surrounding high-density implants which circumvents artefact production by removing the obstruction during imaging. METHODS: Custom 3D printed moulds were used to set cavities in Fricke gel phantoms to allow for the suspension of high density implants in different geometries. This allowed for the metal valve extracted from a temporary tissue expander to be suspended during irradiation, and removed during optical-CT scanning...
January 17, 2017: Medical Physics
https://www.readbyqxmd.com/read/28094067/differential-intensity-projection-for-visualisation-and-quantification-of-plaque-neovascularisation-in-contrast-enhanced-ultrasound-images-of-carotid-arteries
#6
Wing Keung Cheung, Benoy N Shah, Antonio Stanziola, Dorothy M Gujral, Navtej S Chahal, David O Cosgrove, Roxy Senior, Meng-Xing Tang
Studies have reported that intraplaque neovascularisation (IPN) is closely correlated with plaque vulnerability. In this study, a new image processing approach, differential intensity projection (DIP), was developed to visualise and quantify IPN in contrast-enhanced non-linear ultrasound image sequences of carotid arteries. DIP used the difference between the local temporal maximum and the local temporal average signals to identify bubbles against tissue non-linear artefact and noise. The total absolute and relative areas occupied by bubbles within each plaque were calculated to quantify IPN...
January 13, 2017: Ultrasound in Medicine & Biology
https://www.readbyqxmd.com/read/28093693/a-simple-post-mortem-room-angiography-method-for-the-investigation-of-traumatic-basal-subarachnoid-hemorrhage
#7
Christopher P Johnson, Mike Murphy, George A Johnson, Stephen M Wills, Jonathan E Medcalf
Identifying the site of vascular bleeding in fatal cases of traumatic basal subarachnoid hemorrhage (TBSAH) is important, but can be very difficult to achieve when there is extensive blood clot in the posterior cranial fossa. Post mortem angiography in these circumstances has been reported previously but with mixed results, and is rarely used in current practice within the United Kingdom. We have developed a simple and effective post mortem angiography method, using fluoroscopy and clear modern contrast medium, suitable for use in the autopsy room...
January 17, 2017: Forensic Science, Medicine, and Pathology
https://www.readbyqxmd.com/read/28091571/photoacoustic-pump-probe-tomography-of-fluorophores-in-vivo-using-interleaved-image-acquisition-for-motion-suppression
#8
Julia Märk, Asja Wagener, Edward Zhang, Jan Laufer
In fluorophores, the excited state lifetime can be modulated using pump-probe excitation. By generating photoacoustic (PA) signals using simultaneous and time-delayed pump and probe excitation pulses at fluences below the maximum permissible exposure, a modulation of the signal amplitude is observed in fluorophores but not in endogenous chromophores. This provides a highly specific contrast mechanism that can be used to recover the location of the fluorophore using difference imaging. The practical challenges in applying this method to in vivo PA tomography include the typically low concentrations of fluorescent contrast agents, and tissue motion...
January 16, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28090442/can-mri-accurately-detect-pilon-articular-malreduction-a-quantitative-comparison-between-ct-and-3t-mri-bone-models
#9
Shairah Radzi, Constantin Edmond Dlaska, Gary Cowin, Mark Robinson, Jit Pratap, Michael Andreas Schuetz, Sanjay Mishra, Beat Schmutz
BACKGROUND: Pilon fracture reduction is a challenging surgery. Radiographs are commonly used to assess the quality of reduction, but are limited in revealing the remaining bone incongruities. The study aimed to develop a method in quantifying articular malreductions using 3D computed tomography (CT) and magnetic resonance imaging (MRI) models. METHODS: CT and MRI data were acquired using three pairs of human cadaveric ankle specimens. Common tibial pilon fractures were simulated by performing osteotomies to the ankle specimens...
December 2016: Quantitative Imaging in Medicine and Surgery
https://www.readbyqxmd.com/read/28089649/magnetic-resonance-imaging-conditional-devices-luxury-or-real-clinical-need
#10
REVIEW
Sophie I Mavrogeni, George Poulos, Genovefa Kolovou, George Theodorakis
Although the risk of MRI scanning on patients with conventional devices is rather lower than initially thought, the patient's safety can only be assured by using MRI-conditional devices. The most important modifications in MRI-conditional devices include: a) Reduction in ferromagnetic components to reduce magnetic attraction and susceptibility artefacts b) Replacement of reed switch by Hall sensor in order to avoid unpredictable reed switch behaviour c) Lead coil design to minimize lead heating and electrical current induction d) Filter circuitry to prevent damage to internal power supply e) Dedicated pacemaker programming to prevent inappropriate pacemaker inhibition and competing rhythms...
January 9, 2017: Hellenic Journal of Cardiology: HJC, Hellēnikē Kardiologikē Epitheōrēsē
https://www.readbyqxmd.com/read/28088865/mass-spectrometry-of-intact-proteins-reveals-98-u-chemical-artefacts-following-precipitation-in-acetone
#11
Melda Zeynep Güray, Shi Zheng, Alan Austin Doucette
Protein precipitation in acetone is frequently employed ahead of mass spectrometry for sample preconcentration and purification. Unfortunately, acetone is not chemically inert; mass artefacts have previously been observed on glycine-containing peptides when exposed to acetone under acidic conditions. We herein report a distinct chemical modification occurring at the level of intact proteins when incubated in acetone. This artefact manifests as one or more satellite peaks in the MS spectrum of intact protein, spaced 98 u above the mass of the unmodified protein...
January 15, 2017: Journal of Proteome Research
https://www.readbyqxmd.com/read/28088482/combined-spatiotemporal-ica-stica-for-continuous-and-dynamic-lag-structure-analysis-of-mreg-data
#12
Ville Raatikainen, Niko Huotari, Vesa Korhonen, Aleksi Rasila, Janne Kananen, Lauri Raitamaa, Tuija Keinänen, Jussi Kantola, Osmo Tervonen, Vesa Kiviniemi
This study investigated lag structure in the resting-state fMRI by applying a novel independent component (ICA) method to magnetic resonance encephalography (MREG) data. Briefly, the spatial ICA (sICA) was used for defining the frontal and back nodes of the default mode network (DMN), and the temporal ICA (tICA), which is enabled by the high temporal resolution of MREG (TR=100ms), was used to separate both neuronal and physiological components of these two spatial map regions. Subsequently, lag structure was investigated between the frontal (DMNvmpf) and posterior (DMNpcc) DMN nodes using both conventional method with all-time points and a sliding-window approach...
January 11, 2017: NeuroImage
https://www.readbyqxmd.com/read/28087955/water-as-neutral-oral-contrast-agent-in-abdominopelvic-ct-comparing-effectiveness-with-gastrografin-in-the-same-patient
#13
C H Lee, H Z Gu, B A Vellayappan, C H Tan
INTRODUCTION: Positive oral contrast is no longer deemed necessary for abdominopelvic computed tomography (CT) scans. Studies have shown water to be an equally effective oral contrast agent. However, to our knowledge no study has compared effectiveness between gastrografin and water in the same patient, which will provide a more objective evaluation of the two oral contrast agents. We aim to make a head-to-head comparison of water as neutral oral contrast (OC) against gastrografin as positive OC for abdominopelvic CT scans in the same patient...
December 2016: Medical Journal of Malaysia
https://www.readbyqxmd.com/read/28079054/local-dimensionality-determines-imaging-speed-in-localization-microscopy
#14
Patrick Fox-Roberts, Richard Marsh, Karin Pfisterer, Asier Jayo, Maddy Parsons, Susan Cox
Localization microscopy allows biological samples to be imaged at a length scale of tens of nanometres. Live-cell super-resolution imaging is rare, as it is generally assumed to be too slow for dynamic samples. The speed of data acquisition can be optimized by tuning the density of activated fluorophores in each time frame. Here, we show that the maximum achievable imaging speed for a particular structure varies by orders of magnitude, depending on the sample dimensionality (that is, whether the sample is more like a point, a strand or an extended structure such as a focal adhesion)...
January 12, 2017: Nature Communications
https://www.readbyqxmd.com/read/28071765/neural-codes-of-seeing-architectural-styles
#15
Heeyoung Choo, Jack L Nasar, Bardia Nikrahei, Dirk B Walther
Images of iconic buildings, such as the CN Tower, instantly transport us to specific places, such as Toronto. Despite the substantial impact of architectural design on people's visual experience of built environments, we know little about its neural representation in the human brain. In the present study, we have found patterns of neural activity associated with specific architectural styles in several high-level visual brain regions, but not in primary visual cortex (V1). This finding suggests that the neural correlates of the visual perception of architectural styles stem from style-specific complex visual structure beyond the simple features computed in V1...
January 10, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28070869/fast-t1-and-t2-mapping-methods-the-zoomed-u-flare-sequence-compared-with-epi-and-snapshot-flash-for-abdominal-imaging-at-11-7-tesla
#16
Géraldine Pastor, María Jiménez-González, Sandra Plaza-García, Marta Beraza, Torsten Reese
OBJECTIVE: A newly adapted zoomed ultrafast low-angle RARE (U-FLARE) sequence is described for abdominal imaging applications at 11.7 Tesla and compared with the standard echo-plannar imaging (EPI) and snapshot fast low angle shot (FLASH) methods. MATERIALS AND METHODS: Ultrafast EPI and snapshot-FLASH protocols were evaluated to determine relaxation times in phantoms and in the mouse kidney in vivo. Owing to their apparent shortcomings, imaging artefacts, signal-to-noise ratio (SNR), and variability in the determination of relaxation times, these methods are compared with the newly implemented zoomed U-FLARE sequence...
January 9, 2017: Magma
https://www.readbyqxmd.com/read/28070543/data-to-inform-a-social-media-component-for-professional-development-and-practices-a-design-based-research-study
#17
Jeanette Novakovich, Steven Shaw, Sophia Miah
This DIB article includes the course artefacts, instruments, survey data, and descriptive statistics, along with in-depth correlational analysis for the first iteration of a design-based research study on designing curriculum for developing online professional identity and social media practices for a multi-major advanced professional writing course. Raw data was entered into SPSS software. For interpretation and discussion, please see the original article entitled, "Designing curriculum to shape professional social media skills and identity in virtual communities of practice" (J...
February 2017: Data in Brief
https://www.readbyqxmd.com/read/28069162/a-constrained-extended-kalman-filter-for-the-optimal-estimate-of-kinematics-and-kinetics-of-a-sagittal-symmetric-exercise
#18
V Bonnet, R Dumas, A Cappozzo, V Joukov, G Daune, D Kulić, P Fraisse, S Andary, G Venture
This paper presents a method for real-time estimation of the kinematics and kinetics of a human body performing a sagittal symmetric motor task, which would minimize the impact of the stereophotogrammetric soft tissue artefacts (STA). The method is based on a bi-dimensional mechanical model of the locomotor apparatus the state variables of which (joint angles, velocities and accelerations, and the segments lengths and inertial parameters) are estimated by a constrained extended Kalman filter (CEKF) that fuses input information made of both stereophotogrammetric and dynamometric measurement data...
December 29, 2016: Journal of Biomechanics
https://www.readbyqxmd.com/read/28065638/iterative-metal-artefact-reduction-in-ct-can-dedicated-algorithms-improve-image-quality-after-spinal-instrumentation
#19
J Aissa, C Thomas, L M Sawicki, J Caspers, P Kröpil, G Antoch, J Boos
AIM: To investigate the value of dedicated computed tomography (CT) iterative metal artefact reduction (iMAR) algorithms in patients after spinal instrumentation. MATERIALS AND METHODS: Post-surgical spinal CT images of 24 patients performed between March 2015 and July 2016 were retrospectively included. Images were reconstructed with standard weighted filtered back projection (WFBP) and with two dedicated iMAR algorithms (iMAR-Algo1, adjusted to spinal instrumentations and iMAR-Algo2, adjusted to large metallic hip implants) using a medium smooth kernel (B30f) and a sharp kernel (B70f)...
January 5, 2017: Clinical Radiology
https://www.readbyqxmd.com/read/28064512/the-roman-thermal-complex-from-curinga-calabria-italy
#20
Caterina Gattuso, Philomène Gattuso, Valentina Caramazza, Chiara Gallo, Valentina Roviello, Luigi Campanella
Since ancient times, the Calabrian territories were affected continuously and in different dominations: first Magna Greece civilisation and after the Roman domination. The latter influenced strongly some areas of the Calabrian territory, where we witnessed a gradual replacement of small farmer properties with plants of the first Roman villas. An example of Roman thermal plant was in the city of Curinga (CZ), where in 1966 were found the remains of a thermal building dating to late-Roman period, probably a part of a much more complex structure identifiable as a large Roman villa...
January 9, 2017: Natural Product Research
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