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https://www.readbyqxmd.com/read/29044156/open-source-3d-multipurpose-measurement-system-with-submillimetre-fidelity-and-first-application-in-magnetic-resonance
#1
Haopeng Han, Raphael Moritz, Eva Oberacker, Helmar Waiczies, Thoralf Niendorf, Lukas Winter
Magnetic resonance imaging (MRI) is the mainstay of diagnostic imaging, a versatile instrument for clinical science and the subject of intense research interest. Advancing clinical science, research and technology of MRI requires high fidelity measurements in quantity, location and time of the given physical property. To meet this goal a broad spectrum of commercial measurement systems has been made available. These instruments frequently share in common that they are costly and typically employ closed proprietary hardware and software...
October 18, 2017: Scientific Reports
https://www.readbyqxmd.com/read/29042960/application-of-3d-printing-rapid-prototyping-assisted-percutaneous-fixation-in-the-treatment-of-intertrochanteric-fracture
#2
Sheng-Nai Zheng, Qing-Qiang Yao, Feng-Yong Mao, Peng-Fei Zheng, Shu-Chang Tian, Jia-Yi Li, Yi-Fan Yu, Shuai Liu, Jin Zhou, Jun Hu, Yan Xu, Kai Tang, Yue Lou, Li-Ming Wang
The aim of the present study was to investigate the application of 3D printing (3DP) rapid prototyping (RP) technique-assisted percutaneous fixation in the treatment of femoral intertrochanteric fracture (ITF) using proximal femoral nail anti-rotation (PFNA). A total of 39 patients with unstable ITF were included in the current study. Patients were divided into two groups: 19 patients were examined using computed tomography scanning and underwent PFNA with SDP-RP whereas the other 20 patients underwent conventional PFNA treatment...
October 2017: Experimental and Therapeutic Medicine
https://www.readbyqxmd.com/read/29041716/efficient-method-to-measure-the-spectral-distortions-using-periodically-distributed-slit-in-hyperspectral-imager
#3
Jinsuk Hong, Youngsoo Kim, Byungin Choi, Seongryung Hwang, Dohwan Jeong, Jun Ho Lee, Yeonsoo Kim, Hyunsook Kim
The imaging spectrometer generally shows geometrical asymmetric distortions known as the keystone and smile that are different from the regular imaging optical system. The conventional method of measuring such distortions requires a precision movement control stage and specialized optical setup. Moreover, it is even harder to measure other characteristics such as the wave front error (WFE) simultaneously and to repeat the measurements since an accumulated vast number of statistical data is required to calculate the keystone and smile...
August 21, 2017: Optics Express
https://www.readbyqxmd.com/read/29040910/intensity-inhomogeneity-correction-of-sd-oct-data-using-macular-flatspace
#4
Andrew Lang, Aaron Carass, Bruno M Jedynak, Sharon D Solomon, Peter A Calabresi, Jerry L Prince
Images of the retina acquired using optical coherence tomography (OCT) often suffer from intensity inhomogeneity problems that degrade both the quality of the images and the performance of automated algorithms utilized to measure structural changes. This intensity variation has many causes, including off-axis acquisition, signal attenuation, multi-frame averaging, and vignetting, making it difficult to correct the data in a fundamental way. This paper presents a method for inhomogeneity correction by acting to reduce the variability of intensities within each layer...
October 12, 2017: Medical Image Analysis
https://www.readbyqxmd.com/read/29038202/brain-regional-blood-flow-and-working-memory-performance-predict-change-in-blood-pressure-over-2-years
#5
J Richard Jennings, Alicia F Heim, Lei K Sheu, Matthew F Muldoon, Christopher Ryan, H Michael Gach, Claudiu Schirda, Peter J Gianaros
Hypertension is a presumptive risk factor for premature cognitive decline. However, lowering blood pressure (BP) does not uniformly reverse cognitive decline, suggesting that high BP per se may not cause cognitive decline. We hypothesized that essential hypertension has initial effects on the brain that, over time, manifest as cognitive dysfunction in conjunction with both brain vascular abnormalities and systemic BP elevation. Accordingly, we tested whether neuropsychological function and brain blood flow responses to cognitive challenges among prehypertensive individuals would predict subsequent progression of BP...
October 16, 2017: Hypertension
https://www.readbyqxmd.com/read/29036879/enhancement-of-digital-radiography-image-quality-using-a-convolutional-neural-network
#6
Yuewen Sun, Litao Li, Peng Cong, Zhentao Wang, Xiaojing Guo
Digital radiography system is widely used for noninvasive security check and medical imaging examination. However, the system has a limitation of lower image quality in spatial resolution and signal to noise ratio. In this study, we explored whether the image quality acquired by the digital radiography system can be improved with a modified convolutional neural network to generate high-resolution images with reduced noise from the original low-quality images. The experiment evaluated on a test dataset, which contains 5 X-ray images, showed that the proposed method outperformed the traditional methods (i...
October 10, 2017: Journal of X-ray Science and Technology
https://www.readbyqxmd.com/read/29036098/numerical-investigation-of-polarization-filtering-for-direct-optical-imaging-within-scattering-media
#7
Callum M Macdonald, Ugo Tricoli, Anabela Da Silva, Vadim A Markel
We investigate the ability of polarization filtering to improve direct imaging of absorbing objects which are buried within scattering environments. We extend on previous empirical investigations by exploiting an efficient perturbation-based formalism, which is applicable to arbitrarily arranged sources and detectors with arbitrary polarizations. From this approach, we are able in some cases to find certain non-trivial linear combinations of polarization measurement channels that maximize the object resolution and visibility...
August 1, 2017: Journal of the Optical Society of America. A, Optics, Image Science, and Vision
https://www.readbyqxmd.com/read/29036085/local-receptive-field-constrained-stacked-sparse-autoencoder-for-classification-of-hyperspectral-images
#8
Xiaoqing Wan, Chunhui Zhao
As a competitive machine learning algorithm, the stacked sparse autoencoder (SSA) has achieved outstanding popularity in exploiting high-level features for classification of hyperspectral images (HSIs). In general, in the SSA architecture, the nodes between adjacent layers are fully connected and need to be iteratively fine-tuned during the pretraining stage; however, the nodes of previous layers further away may be less likely to have a dense correlation to the given node of subsequent layers. Therefore, to reduce the classification error and increase the learning rate, this paper proposes the general framework of locally connected SSA; that is, the biologically inspired local receptive field (LRF) constrained SSA architecture is employed to simultaneously characterize the local correlations of spectral features and extract high-level feature representations of hyperspectral data...
June 1, 2017: Journal of the Optical Society of America. A, Optics, Image Science, and Vision
https://www.readbyqxmd.com/read/29035233/gii-representation-based-cross-view-gait-recognition-by-discriminative-projection-with-list-wise-constraints
#9
Zhaoxiang Zhang, Jiaxin Chen, Qiang Wu, Ling Shao
Remote person identification by gait is one of the most important topics in the field of computer vision and pattern recognition. However, gait recognition suffers severely from the appearance variance caused by the view change. It is very common that gait recognition has a high performance when the view is fixed but the performance will have a sharp decrease when the view variance becomes significant. Existing approaches have tried all kinds of strategies like tensor analysis or view transform models to slow down the trend of performance decrease but still have potential for further improvement...
October 13, 2017: IEEE Transactions on Cybernetics
https://www.readbyqxmd.com/read/29035208/an-efficient-integral-based-method-for-three-dimensional-mr-ept-and-the-calculation-of-the-rf-coil-induced-field
#10
Lei Guo, Jin Jin, Chunyi Liu, Feng Liu, Stuart Crozier
Magnetic resonance electrical property tomography (MR-EPT) has significant potential for the estimation of the electrical properties (EPs) of tissue, which are essential for the calculation of specific absorption rates (SAR), a critical safety factor requiring monitoring and controlling in applications of ultra-high field magnetic resonance imaging (MRI). In this paper, a novel, efficient method based on integral equations is proposed for the calculation of the EPs and the RF-coil induced field. An inverse problem framework is first constructed to include the forward problem operator, while the EPs are reconstructed by using a non-linear conjugate gradient method (NLCG)...
October 16, 2017: IEEE Transactions on Bio-medical Engineering
https://www.readbyqxmd.com/read/29035035/oxygen-vacancies-and-stacking-faults-introduced-by-low-temperature-reduction-improve-the-electrochemical-properties-of-li2mno3-nanobelts-as-lithium-ion-battery-cathodes
#11
Ya Sun, Hengjiang Cong, Ling Zan, Youxiang Zhang
Among the Li-rich layered oxides Li2MnO3 has significant theoretical capacity as a cathode material for Li-ion batteries. Pristine Li2MnO3 generally has to be electrochemically activated in the first charge-discharge cycle which causes a very low Coulombic efficiency and thus deteriorates its electrochemical properties. In this paper, we show that low-temperature reduction can produce a large amount of structural defects like oxygen vacancies, stacking faults, and orthorhombic LiMnO2 in Li2MnO3. The Rietveld refinement analysis shows that, after a reduction reaction with stearic acid at 340 C for 8 h, pristine Li2MnO3 changes into a Li2MnO3-LiMnO2 (0...
October 16, 2017: ACS Applied Materials & Interfaces
https://www.readbyqxmd.com/read/29034066/novel-spect-technologies-and-approaches-in-cardiac-imaging
#12
Piotr Slomka, Guang-Uei Hung, Guido Germano, Daniel S Berman
Recent novel approaches in myocardial perfusion single photon emission CT (SPECT) have been facilitated by new dedicated high-efficiency hardware with solid-state detectors and optimized collimators. New protocols include very low-dose (1 mSv) stress-only, two-position imaging to mitigate attenuation artifacts, and simultaneous dual-isotope imaging. Attenuation correction can be performed by specialized low-dose systems or by previously obtained CT coronary calcium scans. Hybrid protocols using CT angiography have been proposed...
December 1, 2016: Cardiovasc Innov Appl
https://www.readbyqxmd.com/read/29033612/increased-detection-of-precancerous-cervical-lesions-with-adjunctive-dynamic-spectral-imaging
#13
Sara A DeNardis, Philip T Lavin, Jeff Livingston, William R Salter, Nanette James-Patrick, Emmanouil Papagiannakis, Christopher G Olson, Lori Weinberg
OBJECTIVE: To validate, in US community-based colposcopy clinics, previous reports of increased detection of high-grade cervical intraepithelial neoplasia (CIN2+) with biopsies selected using dynamic spectral imaging (DSI) mapping after standard colposcopy. STUDY DESIGN: Cross-sectional observational study of 26 colposcopists across nine clinics recruiting consecutive colposcopy patients. Standard assessment with biopsy selections was completed before seeing the DSI map which was subsequently interpreted and used for additional biopsies per clinical judgment...
2017: International Journal of Women's Health
https://www.readbyqxmd.com/read/29033293/ct-and-mri-slice-separation-evaluation-by-labview-developed-software
#14
Giuseppe Acri, Barbara Testagrossa, Angela Sestito, Lilla Bonanno, Giuseppe Vermiglio
The efficient use of Computed Tomography (CT) and Magnetic Resonance Imaging (MRI) equipment necessitates establishing adequate quality-control (QC) procedures. In particular, the accuracy of slice separation, during multislices acquisition, requires scan exploration of phantoms containing test objects. To simplify such procedures, a novel phantom and a computerised LabView-based procedure have been devised, enabling determination the midpoint of full width at half maximum (FWHM) in real time while the distance from the profile midpoint of two progressive images is evaluated and measured...
October 13, 2017: Zeitschrift Für Medizinische Physik
https://www.readbyqxmd.com/read/29032683/retrieving-the-quantitative-chemical-information-at-nanoscale-from-scanning-electron-microscope-energy-dispersive-x-ray-measurements-by-machine-learning
#15
B R Jany, A Janas, F Krok
The quantitative composition of metal alloy nanowires on InSb semiconductor surface and gold nanostructures on germanium surface is determined by blind source separation (BSS) machine learning method using non-negative matrix factorization from energy dispersive X-ray spectroscopy (EDX) spectrum image maps measured in a scanning electron microscope (SEM). The BSS method blindly decomposes the collected EDX spectrum image into three source components, which correspond directly to the X-ray signals coming from the supported metal nanostructures, bulk semiconductor signal, and carbon background...
October 18, 2017: Nano Letters
https://www.readbyqxmd.com/read/29029074/multimodality-imaging-evaluation-of-chagas-disease-an-expert-consensus-of-brazilian-cardiovascular-imaging-department-dic-and-the-european-association-of-cardiovascular-imaging-eacvi
#16
Maria Carmo P Nunes, Luigi Paolo Badano, J Antonio Marin-Neto, Thor Edvardsen, Covadonga Fernández-Golfín, Chiara Bucciarelli-Ducci, Bogdan A Popescu, Richard Underwood, Gilbert Habib, Jose Luis Zamorano, Roberto Magalhães Saraiva, Ester Cerdeira Sabino, Fernando A Botoni, Márcia Melo Barbosa, Marcio Vinicius L Barros, Eduardo Falqueto, Marcus Vinicius Simões, André Schmidt, Carlos Eduardo Rochitte, Manoel Otávio Costa Rocha, Antonio Luiz Pinho Ribeiro, Patrizio Lancellotti
Aims: To develop a document by Brazilian Cardiovascular Imaging Department (DIC) and the European Association of Cardiovascular Imaging (EACVI) to review and summarize the most recent evidences about the non-invasive assessment of patients with Chagas disease, with the intent to set up a framework for standardized cardiovascular imaging to assess cardiovascular morphologic and functional disturbances, as well as to guide the subsequent process of clinical decision-making. Methods and results: Chagas disease remains one of the most prevalent infectious diseases in Latin America, and has become a health problem in non-endemic countries...
September 25, 2017: European Heart Journal Cardiovascular Imaging
https://www.readbyqxmd.com/read/29028937/abnormal-structural-brain-connectome-in-individuals-with-preclinical-alzheimer-s-disease
#17
Joana B Pereira, Danielle van Westen, Erik Stomrud, Tor Olof Strandberg, Giovanni Volpe, Eric Westman, Oskar Hansson
Alzheimer's disease has a long preclinical phase during which amyloid pathology and neurodegeneration accumulate in the brain without producing overt cognitive deficits. It is currently unclear whether these early disease stages are associated with a progressive disruption in the communication between brain regions that subsequently leads to cognitive decline and dementia. In this study we assessed the organization of structural networks in cognitively normal (CN) individuals harboring amyloid pathology (A+N-), neurodegeneration (A-N+), or both (A+N+) from the prospective and longitudinal Swedish BioFINDER study...
October 3, 2017: Cerebral Cortex
https://www.readbyqxmd.com/read/29028305/fast-image-guided-stratification-using-anti-programmed-death-ligand-1-gold-nanoparticles-for-cancer-immunotherapy
#18
Rinat Meir, Katerina Shamalov, Tamar Sadan, Menachem Motiei, Gur Yaari, Cyrille J Cohen, Rachela Popovtzer
Cancer immunotherapy has made enormous progress in offering safer and more effective treatments for the disease. Specifically, programmed death-ligand 1 antibody (αPDL1), designed to perform immune checkpoint blockade (ICB), is now considered a pillar in cancer immunotherapy. However, due to the complexity and heterogeneity of tumors, as well as the diversity in patient response, ICB therapy has only a 30 percent success rate, at most; moreover, the efficacy of ICB can be evaluated only two months after start of treatment...
October 13, 2017: ACS Nano
https://www.readbyqxmd.com/read/29027895/changes-in-foraminal-area-with-anterior-decompression-versus-keyhole-foraminotomy-in-the-cervical-spine-a-biomechanical-investigation
#19
Jacqueline Nguyen, Bryant Chu, Calvin C Kuo, Jeremi M Leasure, Christopher Ames, Dimitriy Kondrashov
OBJECTIVE Anterior cervical discectomy and fusion (ACDF) with or without partial uncovertebral joint resection (UVR) and posterior keyhole foraminotomy are established operative procedures to treat cervical disc degeneration and radiculopathy. Studies have demonstrated reliable results with each procedure, but none have compared the change in neuroforaminal area between indirect and direct decompression techniques. The purpose of this study was to determine which cervical decompression method most consistently increases neuroforaminal area and how that area is affected by neck position...
October 13, 2017: Journal of Neurosurgery. Spine
https://www.readbyqxmd.com/read/29022943/simultaneous-measurement-of-sleep-and-feeding-in-individual-drosophila
#20
Keith R Murphy, Jin Hong Park, Robert Huber, William W Ja
Drosophila is widely used for the dissection of genetic and neuronal mechanisms of behavior. Recently, flies have emerged as a model for investigating the regulation of feeding and sleep. Although typically studied in isolation, increasing evidence points to a fundamental connection between these behaviors. Thus, a system for measuring sleep and feeding simultaneously in a single integrated system is important for interpreting behavioral shifts of either state. Here, we describe the construction and use of the Activity Recording Capillary Feeder or CAFE (ARC), a machine-vision (automated image tracking)-based system for the integrated measurement of sleep and feeding in individual Drosophila...
November 2017: Nature Protocols
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