Read by QxMD icon Read

3D mapping

Rajiv G Menon, Azadeh Sharafi, Johannes Windschuh, Ravinder R Regatte
Detection of multiple relaxation pools using MRI is useful in a number of neuro-pathologies including multiple sclerosis (MS), Alzheimer's, and stroke. In this study we evaluate the feasibility of using T1ρ imaging for the detection of bi-exponential decays in the human brain. A prospective T1ρ imaging study was performed on model relaxation phantoms (eggs) and 7 healthy volunteers. The data was fitted using a single pool and a 2-pool model to estimate mono- and bi-exponential T1ρ maps, respectively. Bi-exponential decays were identified in the gray matter (GM) and white matter (WM) of the brain with 40...
January 19, 2018: Scientific Reports
Jing-Yuan Chen, Jun Ho Son, Chao Wang, S Raghu
The idea of statistical transmutation plays a crucial role in descriptions of the fractional quantum Hall effect. However, a recently conjectured duality between a critical boson and a massless two-component Dirac fermion extends this notion to gapless systems. This duality sheds light on highly nontrivial problems such as the half-filled Landau level, the superconductor-insulator transition, and surface states of strongly coupled topological insulators. Although this boson-fermion duality has undergone many consistency checks, it has remained unproven...
January 5, 2018: Physical Review Letters
M Gregor Madej, Christine M Ziegler
Cryo-electron microscopy (cryo-EM) permits the determination of atomic protein structures by averaging large numbers of individual projection images recorded at cryogenic temperatures-a method termed single-particle analysis. The cryo-preservation traps proteins within a thin glass-like ice layer, making literally a freeze image of proteins in solution. Projections of randomly adopted orientations are merged to reconstruct a 3D density map. While atomic resolution for highly symmetric viruses was achieved already in 2009, the development of new sensitive and fast electron detectors has enabled cryo-EM for smaller and asymmetrical proteins including fragile membrane proteins...
January 17, 2018: Pflügers Archiv: European Journal of Physiology
Masami Goto, Osamu Abe, Shigeki Aoki, Koji Kamagata, Masaaki Hori, Tosiaki Miyati, Tsutomu Gomi, Tohoru Takeda
PURPOSE: To evaluate the error in segmented tissue images and to show the usefulness of the brain image in voxel-based morphometry (VBM) using Statistical Parametric Mapping (SPM) 12 software and 3D T1-weighted magnetic resonance images (3D-T1WIs) processed to simulate idiopathic normal pressure hydrocephalus (iNPH). MATERIALS AND METHODS: VBM analysis was performed on sagittal 3D-T1WIs obtained in 22 healthy volunteers using a 1.5T MR scanner. Regions of interest for the lateral ventricles of all subjects were carefully outlined on the original 3D-T1WIs, and two types of simulated 3D-T1WI were also prepared (non-dilated 3D-T1WI as normal control and dilated 3D-T1WI to simulate iNPH)...
January 18, 2018: Magnetic Resonance in Medical Sciences: MRMS
Po-Chang Su, Ju Shen, Wanxin Xu, Sen-Ching S Cheung, Ying Luo
From object tracking to 3D reconstruction, RGB-Depth (RGB-D) camera networks play an increasingly important role in many vision and graphics applications. Practical applications often use sparsely-placed cameras to maximize visibility, while using as few cameras as possible to minimize cost. In general, it is challenging to calibrate sparse camera networks due to the lack of shared scene features across different camera views. In this paper, we propose a novel algorithm that can accurately and rapidly calibrate the geometric relationships across an arbitrary number of RGB-D cameras on a network...
January 15, 2018: Sensors
Yufu Qu, Jianyu Huang, Xuan Zhang
In order to reconstruct three-dimensional (3D) structures from an image sequence captured by unmanned aerial vehicles' camera (UAVs) and improve the processing speed, we propose a rapid 3D reconstruction method that is based on an image queue, considering the continuity and relevance of UAV camera images. The proposed approach first compresses the feature points of each image into three principal component points by using the principal component analysis method. In order to select the key images suitable for 3D reconstruction, the principal component points are used to estimate the interrelationships between images...
January 14, 2018: Sensors
Yan Zhou, Xianwei Zheng, Ruizhi Chen, Hanjiang Xiong, Sheng Guo
Accurately determining pedestrian location in indoor environments using consumer smartphones is a significant step in the development of ubiquitous localization services. Many different map-matching methods have been combined with pedestrian dead reckoning (PDR) to achieve low-cost and bias-free pedestrian tracking. However, this works only in areas with dense map constraints and the error accumulates in open areas. In order to achieve reliable localization without map constraints, an improved image-based localization aided pedestrian trajectory estimation method is proposed in this paper...
January 17, 2018: Sensors
Katsuhiro Masago, Shiro Fujita, Akito Hata, Chiyuki Okuda, Yuko Yoshizumi, Reiko Kaji, Nobuyuki Katakami, Yukio Hirata, Yasushi Yatabe
The aim of this study was to compare the accuracy of the QuantStudio 3D Digital polymerase chain reaction (dPCR) system and a PCR-based next generation sequencing (NGS) system for detecting a secondary mutation in the epidermal growth factor receptor (EGFR) gene T790M in non-small cell lung cancer (NSCLC) patients previously diagnosed with EGFR-activating mutations. Twenty-five patients with NSCLC previously treated with EGFR-TKIs were examined. The patients were treated daily with either erlotinib or gefitinib...
January 17, 2018: Pathology International
Meghna R Beotra, Xiaofei Wang, Tin A Tun, Liang Zhang, Mani Baskaran, Tin Aung, Nicholas G Strouthidis, Michaël J A Girard
Purpose: To compare in vivo lamina cribrosa (LC) strains (deformations) following acute IOP elevation in healthy, glaucoma, and ocular hypertensive subjects. Methods: There were 20 healthy, 20 high-tension primary open-angle glaucoma (POAG), 16 primary angle-closure glaucoma (PACG), and 20 ocular hypertensive (OHT; with normal visual fields) eyes studied. For each test eye, the optic nerve head was imaged three times (at baseline IOP, following an acute elevation of IOP to approximately 35 then 45 mm Hg using an ophthalmodynamomter) using optical coherence tomography (OCT)...
January 1, 2018: Investigative Ophthalmology & Visual Science
Gabriel Cismaru, Mihai Puiu, Radu Rosu, Lucian Muresan, Gabriel Gusetu, Dana Pop, Dumitru Zdrenghea
We present the case of a 59-year-old patient with persistent atrial fibrillation, referred for atrial fibrillation ablation. The procedure was performed with the help of NAVX 3D mapping system (Saint Jude Medical) and iLAB Ultra ICE Plus ultrasound imaging catheter (Boston Scientific). The catheter permits cross-sectional images perpendicular to catheter's long axis. From inside left atrial appendage (LAA) looks trabeculated, due to pectinate muscles running parallel to each other. The presence of a thrombus was excluded from the appendage...
January 2018: Oxford Medical Case Reports
Qilin Hua, Junlu Sun, Haitao Liu, Rongrong Bao, Ruomeng Yu, Junyi Zhai, Caofeng Pan, Zhong Lin Wang
Mechanosensation electronics (or Electronic skin, e-skin) consists of mechanically flexible and stretchable sensor networks that can detect and quantify various stimuli to mimic the human somatosensory system, with the sensations of touch, heat/cold, and pain in skin through various sensory receptors and neural pathways. Here we present a skin-inspired highly stretchable and conformable matrix network (SCMN) that successfully expands the e-skin sensing functionality including but not limited to temperature, in-plane strain, humidity, light, magnetic field, pressure, and proximity...
January 16, 2018: Nature Communications
Albert J Kooistra, Marton Vass, Ross McGuire, Rob Leurs, Iwan Jp de Esch, Gerrit Vriend, Stefan Verhoeven, Chris de Graaf
eScience technologies are needed to process the information available in many heterogeneous types of protein-ligand interaction data and to capture these data into models that enable the design of efficacious and safe medicines. Here we present scientific KNIME tools and workflows that enable the integration of chemical, pharmacological, and structural information for: i) structure-based bioactivity data mapping, ii) structure-based identification of scaffold replacement strategies for ligand design, iii) ligand-based target prediction, iv) protein sequence-based binding site identification and ligand repurposing, and v) structure-based pharmacophore comparison for ligand repurposing across protein families...
January 16, 2018: ChemMedChem
Ottilie von Loeffelholz, Gabor Papai, Radostin Danev, Alexander G Myasnikov, S Kundhavai Natchiar, Isabelle Hazemann, Jean-François Ménétret, Bruno P Klaholz
A current bottleneck in structure determination of macromolecular complexes by cryo electron microscopy (cryo-EM) is the large amount of data needed to obtain high-resolution 3D reconstructions, including through sorting into different conformations and compositions with advanced image processing. Additionally, it may be difficult to visualize small ligands that bind in sub-stoichiometric levels. Volta phase plates (VPP) introduce a phase shift in the contrast transfer and drastically increase the contrast of the recorded low-dose cryo-EM images while preserving high frequency information...
January 11, 2018: Journal of Structural Biology
Temel Tirkes, Chen Lin, Enming Cui, Yu Deng, Paul R Territo, Kumaresan Sandrasegaran, Fatih Akisik
OBJECTIVE: The purpose of this study was to determine if extracellular volume fraction and T1 mapping can be used to diagnose chronic pancreatitis (CP). MATERIALS AND METHODS: This HIPAA-compliant study analyzed 143 consecutive patients with and without CP who underwent MR imaging between May 2016 and February 2017. Patients were selected for the study according to inclusion and exclusion criteria that considered history and clinical and laboratory findings. Eligible patients (n = 119) were grouped as normal (n = 60) or with mild (n = 22), moderate (n = 27), or severe (n = 10) CP on the basis of MRCP findings using the Cambridge classification as the reference standard...
January 16, 2018: AJR. American Journal of Roentgenology
Yang Fang, Ming Chen, Haoran Xu, Peichao Li, Chao Han, Jiaming Hu, Shude Zhu, Heng Ma, Haidong D Lu
Binocular disparity information is an important source of 3D perception. Neurons sensitive to binocular disparity are found in almost all major visual areas in nonhuman primates. In area V4, disparity processes are suggested for the purposes of 3D-shape representation and fine disparity perception. However, whether neurons in V4 are sensitive to disparity-defined edges used in shape representation is not clear. Additionally, a functional organization for disparity edges has not been demonstrated so far. With intrinsic signal optical imaging, we studied functional organization for disparity edges in the monkey visual areas V1, V2, and V4...
January 10, 2018: Cerebral Cortex
Di Jin, Renjie Zhou, Zahid Yaqoob, Peter T C So
Optical diffraction tomography (ODT) is an emerging microscopy technique for three-dimensional (3D) refractive index (RI) mapping of transparent specimens. Recently, the digital micromirror device (DMD) based scheme for angle-controlled plane wave illumination has been proposed to improve the imaging speed and stability of ODT. However, undesired diffraction noise always exists in the reported DMD-based illumination scheme, which leads to a limited contrast ratio of the measurement fringe and hence inaccurate RI mapping...
January 8, 2018: Optics Express
Zewei Cai, Xiaoli Liu, Xiang Peng, Bruce Z Gao
Technologies and devices for light field imaging have recently been developed for both industrial applications and scientific research to achieve excellent imaging properties. In our previous work, we combined light field imaging with structured illumination to propose a structured light field method in which multidirectional depth estimation can be performed for high-quality 3D imaging. However, the projection axis was implicitly assumed to be perpendicular to the reference plane, which is hard to meet in practice...
January 1, 2018: Applied Optics
Raul Castañeda, Jorge Garcia-Sucerquia
In this work, an off-axis digital holographic microscope operating in reflection mode and a telecentric regimen to produce 3D topography of a microscopy sample is shown. The main characteristics of the proposed method, which make it different from the previous works in the field, are the possibility of producing the 3D topography by a single shot over the complete field of view with sensitivity of λ/100, without phase perturbations introduced by the illuminating-imaging system, and with no further numerical processing beyond that required for recovering the phase map of the sample...
January 1, 2018: Applied Optics
Eirik T B Skjønsfjell, David Kleiven, Nilesh Patil, Yuriy Chushkin, Federico Zontone, Alain Gibaud, Dag W Breiby
Coherent x-ray diffraction imaging (CXDI) is becoming an important 3D quantitative microscopy technique, allowing structural investigation of a wide range of delicate mesoscale samples that cannot be imaged by other techniques like electron microscopy. Here we report high-resolution 3D CXDI performed on spherical microcomposites consisting of a polymer core coated with a triple layer of nickel-gold-silica. These composites are of high interest to the microelectronics industry, where they are applied in conducting adhesives as fine-pitch electrical contacts-which requires an exceptional degree of uniformity and reproducibility...
January 1, 2018: Journal of the Optical Society of America. A, Optics, Image Science, and Vision
P Xiu, Q Liu, X Zhou, Y Xu, C Kuang, X Liu
The refractive index (RI) of a sample as an endogenous contrast agent plays an important role in transparent live cell imaging. In tomographic phase microscopy (TPM), 3D quantitative RI maps can be reconstructed based on the measured projections of the RI in multiple directions. The resolution of the RI maps not only depends on the numerical aperture of the employed objective lens, but also is determined by the accuracy of the quantitative phase of the sample measured at multiple scanning illumination angles...
January 11, 2018: Journal of Microscopy
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"