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https://www.readbyqxmd.com/read/28231402/ex-vivo-visualization-of-human-ciliated-epithelium-and-quantitative-analysis-of-induced-flow-dynamics-by-using-optical-coherence-tomography
#1
Yuye Ling, Xinwen Yao, Ute A Gamm, Emilio Arteaga-Solis, Charles W Emala, Michael A Choma, Christine P Hendon
BACKGROUND AND OBJECTIVE: Cilia-driven mucociliary clearance is an important self-defense mechanism of great clinical importance in pulmonary research. Conventional light microscopy possesses the capability to visualize individual cilia and its beating pattern but lacks the throughput to assess the global ciliary activities and flow dynamics. Optical coherence tomography (OCT), which provides depth-resolved cross-sectional images, was recently introduced to this area. MATERIALS AND METHODS: Fourteen de-identified human tracheobronchial tissues are directly imaged by two OCT systems: one system centered at 1,300 nm with 6...
February 23, 2017: Lasers in Surgery and Medicine
https://www.readbyqxmd.com/read/28230223/observation-of-charge-transfer-cascades-in-%C3%AE-fe2o3-irox-photoanodes-by-operando-x-ray-absorption-spectroscopy
#2
Alessandro Minguzzi, Alberto Naldoni, Ottavio Lugaresi, Elisabetta Achilli, Francesco D'Acapito, Francesco Malara, Cristina Locatelli, Alberto Vertova, Sandra Rondinini, Paolo Ghigna
Electrochemical devices for energy conversion and storage are central for a sustainable economy. The performance of electrodes is driven by charge transfer across different layer materials and an understanding of the mechanistics is pivotal to gain improved efficiency. Here, we directly observe the transfer of photogenerated charge carriers in a photoanode made of hematite (α-Fe2O3) and a hydrous iridium oxide (IrOx) overlayer, which plays a key role in photoelectrochemical water oxidation. Through the use of operando X-ray absorption spectroscopy (XAS), we probe the change in occupancy of the Ir 5d levels during optical band gap excitation of α-Fe2O3...
February 22, 2017: Physical Chemistry Chemical Physics: PCCP
https://www.readbyqxmd.com/read/28228436/triamcinolone-emboli-leading-to-central-retinal-artery-occlusion-a-multimodal-imaging-study
#3
Nripen Gaur, Pallavi Singh, Rohan Chawla, Brijesh Takkar
A 19-year-old man presented with unilateral sudden onset vision loss following an intra-articular triamcinolone injection in the right temporomandibular joint. At fundus examination emboli of triamcinolone were visible in multiple retinal arteries. Choroidal ischaemia and occlusion of the central retinal artery and its branches were documented at fluorescein angiography. Optical coherence tomography revealed significant thickening of the inner retinal layers. Optical coherence tomography angiography clearly demonstrated an abrupt cut-off of flow in a vessel below the optic disc...
February 22, 2017: BMJ Case Reports
https://www.readbyqxmd.com/read/28227682/development-of-ocular-viscosity-characterization-method
#4
Shu-Hao Lu, Guo-Zhen Chen, Stanley Y Y Leung, David C C Lam, Shu-Hao Lu, Guo-Zhen Chen, Stanley Y Y Leung, David C C Lam, David C C Lam, Shu-Hao Lu, Guo-Zhen Chen, Stanley Y Y Leung
Glaucoma is the second leading cause for blindness. Irreversible and progressive optic nerve damage results when the intraocular pressure (IOP) exceeds 21 mmHg. The elevated IOP is attributed to blocked fluid drainage from the eye. Methods to measure the IOP are widely available, but methods to measure the viscous response to blocked drainage has yet been developed. An indentation method to characterize the ocular flow is developed in this study. Analysis of the load-relaxation data from indentation tests on drainage-controlled porcine eyes showed that the blocked drainage is correlated with increases in ocular viscosity...
August 2016: Conference Proceedings: Annual International Conference of the IEEE Engineering in Medicine and Biology Society
https://www.readbyqxmd.com/read/28227671/imquant-an-image-based-fluorescence-reader-for-quantitative-lateral-flow-immunoassays
#5
Kaushik Basak Chowdhury, Jayaraj Joseph, Jayaraman Kiruthi Vasan, Mohanasankar Sivaprakasam, Kaushik Basak Chowdhury, Jayaraj Joseph, Jayaraman Kiruthi Vasan, Mohanasankar Sivaprakasam, Jayaraman Kiruthi Vasan, Mohanasankar Sivaprakasam, Jayaraj Joseph, Kaushik Basak Chowdhury
Fluorescence immunoassays (FIA) have strong potential in enabling rapid quantitative immunological testing at point of care. Existing state of the art instruments employ laser scanning of FIA test kits, which require the use of electromechanical systems, making the instrument bulky, heavy and less reliable in the long term. There is a growing need for an extremely compact and reliable, motion-free, automated reader for accurate quantification of immunoassays. Here, we present ImQuant, an image based FIA reader with integrated monochromatic excitation source, optical filtering and real time image capture, assisted with an intuitive graphical user interface...
August 2016: Conference Proceedings: Annual International Conference of the IEEE Engineering in Medicine and Biology Society
https://www.readbyqxmd.com/read/28227375/motion-invariant-contrast-enhancement-of-optical-imaging-data-in-the-gradient-domain
#6
Philipp Flotho, Alejandro Romero-Santiago, Karsten Schwerdtfeger, Jacek Szczygielski, Matthias Hulser, Lars Haab, Daniel J Strauss, Philipp Flotho, Alejandro Romero-Santiago, Karsten Schwerdtfeger, Jacek Szczygielski, Matthias Hulser, Lars Haab, Daniel J Strauss, Daniel J Strauss, Alejandro Romero-Santiago, Jacek Szczygielski, Karsten Schwerdtfeger, Philipp Flotho, Lars Haab
Functional optical imaging (OI) of intrinsic signals (like blood oxygenation coupled reflection changes) and of extrinsic properties of voltage sensitive probes (like voltage-sensitive dyes (VSD)) forms a group of neuroimaging techniques that possess up to date highest temporal and spatial resolution on a meso-to macroscopic scale. An inherent problem of OI is a very low signal to noise ratio (SNR), which restricts the recordings to be completely motionless and requires detailed knowledge of the properties of the different noise sources...
August 2016: Conference Proceedings: Annual International Conference of the IEEE Engineering in Medicine and Biology Society
https://www.readbyqxmd.com/read/28227126/cardiac-muscle-energetics-improved-normalisation-of-heat-using-optical-coherence-tomography
#7
Ming L Cheuk, Callum M Johnston, June-Chiew Han, Denis S Loiselle, Poul M F Nielsen, Andrew J Taberner, Ming L Cheuk, Callum M Johnston, June-Chiew Han, Denis S Loiselle, Poul M F Nielsen, Andrew J Taberner, June-Chiew Han, Callum M Johnston, Poul M F Nielsen, Ming L Cheuk, Denis S Loiselle, Andrew J Taberner
Heat liberated from isolated cardiac muscle has been used to inform us of thermo-mechanical processes that occur during a contraction. However, for comparisons between different samples to be useful, the heat output needs to be normalized to volume. We have implemented an optical coherence tomograph (OCT), together with a flow-through calorimeter, to accurately determine both muscle volume and heat in the same measurement chamber. The heat rate for multiple stimulation frequencies were recorded and normalized to the volume captured by the OCT...
August 2016: Conference Proceedings: Annual International Conference of the IEEE Engineering in Medicine and Biology Society
https://www.readbyqxmd.com/read/28227078/real-time-respiration-rate-measurement-from-thoracoabdominal-movement-with-a-consumer-grade-camera
#8
Avishek Chatterjee, A P Prathosh, Pragathi Praveena, Avishek Chatterjee, A P Prathosh, Pragathi Praveena, Avishek Chatterjee, A P Prathosh, Pragathi Praveena
In this paper, we propose a novel computer vision technique to measure respiration rate by counting the periodic thoracoabdominal motion in real-time using an inexpensive consumer grade camera. We compute the component of optical flow parallel to the image gradient at each pixel, which is a computationally inexpensive operation. Then, we find a principal flow field by gathering information over many frames. Subsequently, in each frame, we compute the component of flow along this principal flow field to capture the thoracoabdominal motion...
August 2016: Conference Proceedings: Annual International Conference of the IEEE Engineering in Medicine and Biology Society
https://www.readbyqxmd.com/read/28226737/4d-lung-tumor-segmentation-via-shape-prior-and-motion-cues
#9
Jung Won Cha, Mohammad M Farhangi, Neal Dunlap, Amir Amini, Jung Won Cha, Mohammad M Farhangi, Neal Dunlap, Amir Amini, Jung Won Cha, Amir Amini, Neal Dunlap, Mohammad M Farhangi
Lung tumor segmentation is important for therapy in the radiation treatment of patients with thoracic malignancies. In this paper, we describe a 4D image segmentation method based on graph-cuts optimization, shape prior and optical flow. Due to small size, the location, and low contrast between the tumor and the surrounding tissue, tumor segmentation in 3D+t is challenging. We performed 4D lung tumor segmentation in 5 patients, and in each case compared the results with the expert-delineated lung nodules. In each case, 4D image segmentation took approximately ten minutes on a PC with AMD Phenom II and 32GB of memory for segmenting tumor in five phases of lung CT data...
August 2016: Conference Proceedings: Annual International Conference of the IEEE Engineering in Medicine and Biology Society
https://www.readbyqxmd.com/read/28226538/sheathless-and-high-throughput-sorting-of-paramagnetic-microparticles-in-a-magneto-hydrodynamic-microfluidic-device
#10
Vikash Kumar, Pouya Rezai, Vikash Kumar, Pouya Rezai, Vikash Kumar, Pouya Rezai
Sorting of microorganisms and particles from a mixture is critical for numerous biotechnological and medical applications. Several sorting methods such as pinched flow fractionation (PFF), optical sorting, dielectrophoresis, acoustic separation, magnetophoresis and deterministic lateral displacement (DLD) have been reported in literature. But most of these methods lack ideal characteristics of a sorter such as ability to process at high throughput, simple design, non-complicated fabrication method, sheathless operation and high purity in separation...
August 2016: Conference Proceedings: Annual International Conference of the IEEE Engineering in Medicine and Biology Society
https://www.readbyqxmd.com/read/28226474/estimation-of-arterio-venous-access-blood-flow-in-hemodialysis-patients-using-video-image-processing-technique
#11
Fansan Zhu, Schantel Williams, Hannah Putnam, Israel Campos, Jie Ma, Camille Johnson, Franz Kappel, Peter Kotanko, Fansan Zhu, Schantel Williams, Hannah Putnam, Israel Campos, Jie Ma, Camille Johnson, Franz Kappel, Peter Kotanko, Jie Ma, Israel Campos, Peter Kotanko, Schantel Williams, Franz Kappel, Fansan Zhu, Hannah Putnam, Camille Johnson
Assessment of arterio-venous fistula (AVF) blood flow (ABF) is vital in hemodialysis (HD) patients. Currently, no non-invasive and contact-free technique is available to accurately measure ABF in routine clinical practice. In this study, we developed a novel approach using video image processing (VIP) to measure the change in optic flow in the skin. We the tested the hypothesis that the change in optical flow, expressed as the change in pixels between consecutive frames, is related to ABF. We recorded AVF videos in 40 HD patients using a digital camera and processed them by VIP technique...
August 2016: Conference Proceedings: Annual International Conference of the IEEE Engineering in Medicine and Biology Society
https://www.readbyqxmd.com/read/28223179/biological-aspects-of-axonal-damage-in-glaucoma-a-brief-review
#12
REVIEW
Ernst R Tamm, C Ross Ethier, Claude Burgoyne, C Ross Ethier, Ernst R Tamm, Cheri Stowell, John E Dowling, Crawford Downs, Mark H Ellisman, Steven Fisher, Brad Fortune, Marcus Fruttiger, Tatjana Jakobs, Geoffrey Lewis, Claire H Mitchell, John Morrison, Sansar C Sharma, Ian Sigal, Michael Sofroniew, Lin Wang, Janey Wiggs, Samuel Wu, Richard H Masland
Intraocular pressure (IOP) is a critical risk factor in glaucoma, and the available evidence derived from experimental studies in primates and rodents strongly indicates that the site of IOP-induced axonal damage in glaucoma is at the optic nerve head (ONH). However, the mechanisms that cause IOP-induced damage at the ONH are far from understood. A possible sequence of events could originate with IOP-induced stress in the ONH connective tissue elements (peripapillary sclera, scleral canal and lamina cribrosa) that leads to an increase in biomechanical strain...
February 18, 2017: Experimental Eye Research
https://www.readbyqxmd.com/read/28222889/pre-cancer-risk-assessment-in-habitual-smokers-from-dic-images-of-oral-exfoliative-cells-using-active-contour-and-svm-analysis
#13
Susmita Dey, Ripon Sarkar, Kabita Chatterjee, Pallab Datta, Ananya Barui, Santi P Maity
Habitual smokers are known to be at higher risk for developing oral cancer, which is increasing at an alarming rate globally. Conventionally, oral cancer is associated with high mortality rates, although recent reports show the improved survival outcomes by early diagnosis of disease. An effective prediction system which will enable to identify the probability of cancer development amongst the habitual smokers, is thus expected to benefit sizable number of populations. Present work describes a non-invasive, integrated method for early detection of cellular abnormalities based on analysis of different cyto-morphological features of exfoliative oral epithelial cells...
February 9, 2017: Tissue & Cell
https://www.readbyqxmd.com/read/28222860/highly-efficient-chiral-separation-of-amlodipine-enantiomers-via-triple-recognition-hollow-fiber-membrane-extraction
#14
Shenzhi Lai, Shaotan Tang, Jiaqi Xie, Changqun Cai, Xiaoming Chen, Chunyan Chen
In this study, a triple recognition chiral extraction process has been developed to separate (S)-amlodipine from racemic raw medicine, based on the combination of molecularly imprinted hollow fiber membrane and cross-flow biphasic recognition extraction. The chiral separation process was operated in a dismountable hollow fiber module coated with molecularly imprinted polymer, and the cross-flow extraction was applied with d-tartaric acid in feed phase and sulfobutyl ether-β-cyclodextrin in stripping phase...
February 14, 2017: Journal of Chromatography. A
https://www.readbyqxmd.com/read/28221028/characterization-of-an-airborne-laser-spark-ion-source-for-ambient-mass-spectrometry
#15
Andreas Bierstedt, Hendrik Kersten, Reto Glaus, Igor B Gornushkin, Ulrich Panne, Jens Riedel
An airborne laser plasma is suggested as an ambient ion source for mass spectrometry. Its fundamental physical properties, such as an excellent spatial and temporal definition, high electron and ion densities and a high effective cross section in maintaining the plasma, make it a promising candidate for future applications. For deeper insights into the plasma properties, the optical plasma emission is examined and compared to mass spectra. The results show a seemingly contradictory behavior, since the emitted light reports the plasma to almost entirely consist of hot elemental ions, while the corresponding mass spectra exhibit the formation of intact molecular species...
February 21, 2017: Analytical Chemistry
https://www.readbyqxmd.com/read/28219996/electrical-tuning-of-the-polarization-state-of-light-using-graphene-integrated-anisotropic-metasurfaces
#16
Shourya Dutta-Gupta, Nima Dabidian, Iskandar Kholmanov, Mikhail A Belkin, Gennady Shvets
Plasmonic metasurfaces have been employed for moulding the flow of transmitted and reflected light, thereby enabling numerous applications that benefit from their ultra-thin sub-wavelength format. Their appeal is further enhanced by the incorporation of active electro-optic elements, paving the way for dynamic control of light's properties. In this paper, we realize a dynamic polarization state generator using a graphene-integrated anisotropic metasurface (GIAM) that converts the linear polarization of the incident light into an elliptical one...
March 28, 2017: Philosophical Transactions. Series A, Mathematical, Physical, and Engineering Sciences
https://www.readbyqxmd.com/read/28214930/investigation-of-optical-neuro-monitoring-technique-for-detection-of-maintenance-and-emergence-states-during-general-anesthesia
#17
Gabriela Hernandez-Meza, Meltem Izzetoglu, Mary Osbakken, Michael Green, Hawa Abubakar, Kurtulus Izzetoglu
The American Society of Anesthesiologist recommends peripheral physiological monitoring during general anesthesia, which offers no information regarding the effects of anesthetics on the brain. Since no "gold standard" method exists for this evaluation, such a technique is needed to ensure patient comfort, procedure quality and safety. In this study we investigated functional near infrared spectroscopy (fNIRS) as possible monitor of anesthetic effects on the prefrontal cortex. Anesthetic drugs, such as sevoflurane, suppress the cerebral metabolism and alter the cerebral blood flow...
February 18, 2017: Journal of Clinical Monitoring and Computing
https://www.readbyqxmd.com/read/28213248/multi-reverse-flow-injection-analysis-integrated-with-multi-optical-sensor-for-simultaneous-determination-of-mn-ii-fe-ii-cu-ii-and-fe-iii-in-natural-waters
#18
Napaporn Youngvises, Kittigan Suwannasaroj, Jaroon Jakmunee, Awadh AlSuhaimi
Multi-reverse flow injection analysis (Mr-FIA) integrated with multi-optical sensor was developed and optimized for the simultaneous determination of multi ions; Mn(II), Fe(II), Cu(II) and Fe(III) in water samples. The sample/standard solutions were propelled making use of a four channels peristaltic pump whereas 4 colorimetric reagents specific for the metal ions were separately injected in sample streams using multi-syringe pump. The color zones that formed in the individual mixing coils were then streamed into multi-channels spectrometer, which comprised of four flows through cell and four pairs of light emitting diode and photodiode, whereby signals were measured concurrently...
May 1, 2017: Talanta
https://www.readbyqxmd.com/read/28212878/evaluation-of-macular-vascular-abnormalities-identified-by-optical-coherence-tomography-angiography-in-sickle-cell-disease
#19
Ian C Han, Mongkol Tadarati, Katia D Pacheco, Adrienne W Scott
PURPOSE: To evaluate macular vascular flow abnormalities identified by optical coherence tomography angiography (OCT-A) in patients with various sickle cell genotypes. DESIGN: Prospective, observational case series. METHODS: This is a single institution case series of adult patients with various sickle cell genotypes. All patients underwent macular OCT-A (Avanti RTVue XR, Optovue Inc, Fremont, CA). Images were analyzed qualitatively for areas of flow loss and quantitatively for measures of foveal avascular area, parafoveal flow, and vascular density...
February 14, 2017: American Journal of Ophthalmology
https://www.readbyqxmd.com/read/28212268/optical-sensor-of-thermal-gas-flow-based-on-fiber-bragg-grating
#20
Xu Jiang, Keda Wang, Junqing Li, Hui Zhan, Zhenan Song, Guohang Che, Guohui Lyu
This paper aims at solving the problem of explosion proof in measurement of thermal gas flow using electronic sensor by presenting a new type of flow sensor by optical fiber heating. A measuring unit based on fiber Bragg grating (FBG) for fluid temperature and a unit for heat dissipation are designed to replace the traditional electronic sensors. The light in C band from the amplified spontaneous emission (ASE) light source is split, with one part used to heat the absorbing coating and the other part used in the signal processing unit...
February 15, 2017: Sensors
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