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https://www.readbyqxmd.com/read/28214930/investigation-of-optical-neuro-monitoring-technique-for-detection-of-maintenance-and-emergence-states-during-general-anesthesia
#1
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
#2
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
#3
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
#4
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
https://www.readbyqxmd.com/read/28211879/evaluation-of-choroidal-tumors-with-optical-coherence-tomography-enhanced-depth-imaging-and-oct-angiography-features
#5
G Cennamo, M R Romano, M A Breve, N Velotti, M Reibaldi, G de Crecchio, G Cennamo
AimTo describe the vascular features of choroidal tumors using enhanced depth imaging (EDI), optical coherence tomography (OCT), and OCT-angiography.MethodsIn this prospective study, we evaluated 116 Caucasian patients with choroidal tumors (60 eyes with choroidal nevi, 40 with choroidal melanoma, 6 with choroidal hemangioma, 2 with optic disc melanocytoma, 6 with choroidal osteoma, and 2 with retinal metastases). Patients underwent a complete ophthalmic examination including bulbar echography, EDI-OCT, OCT-angiography, and multicolor imaging...
February 17, 2017: Eye
https://www.readbyqxmd.com/read/28211263/increased-regurgitant-flow-causes-endocardial-cushion-defects-in-an-avian-embryonic-model-of-congenital-heart-disease
#6
Stephanie M Ford, Matthew T McPheeters, Yves T Wang, Pei Ma, Shi Gu, James Strainic, Christopher Snyder, Andrew M Rollins, Michiko Watanabe, Michael W Jenkins
BACKGROUND: The relationship between changes in endocardial cushion and resultant congenital heart diseases (CHD) has yet to be established. It has been shown that increased regurgitant flow early in embryonic heart development leads to endocardial cushion defects, but it remains unclear how abnormal endocardial cushions during the looping stages might affect the fully septated heart. The goal of this study was to reproducibly alter blood flow in vivo and then quantify the resultant effects on morphology of endocardial cushions in the looping heart and on CHDs in the septated heart...
February 17, 2017: Congenital Heart Disease
https://www.readbyqxmd.com/read/28209526/robust-size-illusion-produced-by-expanding-and-contracting-flow-fields
#7
Xue Dong, Jianying Bai, Min Bao
A new illusion is described. Randomly positioned dots moved radially within an imaginary annular window. The dots' motion periodically changed the direction, leading to an alternating percept of expanding and contracting motion. Strikingly, the apparent size of the enclosed circular region shrank during the dots' expanding phases and dilated during the contracting phases. We quantitatively measured the illusion, and found that the presence of energy at the local kinetic edge could not account for the illusion...
February 13, 2017: Vision Research
https://www.readbyqxmd.com/read/28208231/fast-left-ventricle-tracking-using-localized-anatomical-affine-optical-flow
#8
Sandro Queirós, João L Vilaça, Pedro Morais, Jaime C Fonseca, Jan D'hooge, Daniel Barbosa
In daily clinical cardiology practice, left ventricle (LV) global and regional function assessment is crucial for disease diagnosis, therapy selection and patient follow-up. Currently, this is still a time-consuming task, spending valuable human resources. In this work, a novel fast methodology for automatic LV tracking is proposed based on localized anatomically constrained affine optical flow. This novel method can be combined to previously proposed segmentation frameworks or manually delineated surfaces at an initial frame to obtain fully delineated datasets and, thus, assess both global and regional myocardial function...
February 16, 2017: International Journal for Numerical Methods in Biomedical Engineering
https://www.readbyqxmd.com/read/28205518/superconductivity-in-a-chiral-nanotube
#9
F Qin, W Shi, T Ideue, M Yoshida, A Zak, R Tenne, T Kikitsu, D Inoue, D Hashizume, Y Iwasa
Chirality of materials are known to affect optical, magnetic and electric properties, causing a variety of nontrivial phenomena such as circular dichiroism for chiral molecules, magnetic Skyrmions in chiral magnets and nonreciprocal carrier transport in chiral conductors. On the other hand, effect of chirality on superconducting transport has not been known. Here we report the nonreciprocity of superconductivity-unambiguous evidence of superconductivity reflecting chiral structure in which the forward and backward supercurrent flows are not equivalent because of inversion symmetry breaking...
February 16, 2017: Nature Communications
https://www.readbyqxmd.com/read/28205347/robust-universal-nonrigid-motion-correction-framework-for-first-pass-cardiac-mr-perfusion-imaging
#10
Mitchel Benovoy, Matthew Jacobs, Farida Cheriet, Nagib Dahdah, Andrew E Arai, Li-Yueh Hsu
PURPOSE: To present and assess an automatic nonrigid image registration framework that compensates motion in cardiac magnetic resonance imaging (MRI) perfusion series and auxiliary images acquired under a wide range of conditions to facilitate myocardial perfusion quantification. MATERIALS AND METHODS: Our framework combines discrete feature matching for large displacement estimation with a dense variational optical flow formulation in a multithreaded architecture...
February 15, 2017: Journal of Magnetic Resonance Imaging: JMRI
https://www.readbyqxmd.com/read/28199219/clinical-applications-of-near-infrared-diffuse-correlation-spectroscopy-and-tomography-for-tissue-blood-flow-monitoring-and-imaging
#11
Yu Shang, Ting Li, Guoqiang Yu
Near-infrared (NIR) light enables the deep tissue investigation of microvascular hemodynamics. Blood flow is one such available observable promoting a wealth of physiological insight both individually and in combination with other metrics. Diffuse correlation spectroscopy (DCS) and, to a lesser extent, diffuse correlation tomography (DCT), have received interest over the past two decades as noninvasive methods for tissue blood flow measurement and imaging. DCS employs coherent point-illumination NIR light to penetrate deep tissues and commonly uses avalanche photodiodes to detect temporal speckle fluctuations of the diffuse light in a single speckle area of tissue surface, which are sensitive to the motions of red blood cells in the microvasculature of the detected tissue volume...
February 15, 2017: Physiological Measurement
https://www.readbyqxmd.com/read/28198786/optical-coherence-tomography-angiography-in-adult-onset-foveomacular-vitelliform-dystrophy
#12
Komal M Joshi, Peter L Nesper, Amani A Fawzi, Rukhsana G Mirza
PURPOSE: To determine the ability of optical coherence tomography angiography (OCTA) to detect choroidal neovascularization (CNV) in the pseudohypopyon stage of adult-onset foveomacular vitelliform dystrophy. METHODS: Prospective case series of eight consecutive patients with adult-onset foveomacular vitelliform dystrophy with at least one eye in the pseudohypopyon stage (a total of 14 eyes). Patients were assessed with spectral domain OCT, flourescein angiography, and OCTA...
February 14, 2017: Retina
https://www.readbyqxmd.com/read/28197836/does-direction-of-walking-impact-binocular-rivalry-between-competing-patterns-of-optic-flow
#13
Richard Paris, Bobby Bodenheimer, Randolph Blake
When dissimilar monocular images are viewed simultaneously by the two eyes, stable binocular vision gives way to unstable vision characterized by alternations in dominance between the two images in a phenomenon called binocular rivalry. These alternations in perception reveal the existence of inhibitory interactions between neural representations associated with conflicting visual inputs. Binocular rivalry has been studied since the days of Wheatstone, but one recent strategy is to investigate its susceptibility to influences caused by one's own motor activity...
February 14, 2017: Attention, Perception & Psychophysics
https://www.readbyqxmd.com/read/28197030/superperc-a-new-technique-in-minimally-invasive-percutaneous-nephrolithotomy
#14
Kaushik Shah, Madhu Sudan Agrawal, Dilip Kumar Mishra
INTRODUCTION: Percutaneous nephrolithotomy (PCNL) has undergone significant changes in recent years in the quest for improving efficacy and reducing morbidity. Newer minimally-invasive modalities of PCNL such as mini-PCNL, ultra-mini PCNL, and micro-PCNL have evolved with advancement in optics and technology. However, with these newer advancements, migration of small fragments produced with laser lithotripsy remains a concern, which may result in incomplete stone clearance. We describe a new technique of PCNL termed "Superperc", that utilizes suction to remove all the fragments and maintain one-way flow...
January 2017: Indian Journal of Urology: IJU: Journal of the Urological Society of India
https://www.readbyqxmd.com/read/28196198/en-face-doppler-optical-coherence-tomography-measurement-of-total-retinal-blood-flow-in-diabetic-retinopathy-and-diabetic-macular-edema
#15
ByungKun Lee, Eduardo A Novais, Nadia K Waheed, Mehreen Adhi, Talisa E de Carlo, Emily D Cole, Eric M Moult, WooJhon Choi, Mark Lane, Caroline R Baumal, Jay S Duker, James G Fujimoto
Importance: Alterations in ocular blood flow play an important role in the pathogenesis and progression of diabetic retinopathy (DR). However, the measurement of retinal blood flow in clinical studies has been challenging. En face Doppler optical coherence tomography (OCT) provides an effective method for measuring total retinal blood flow (TRBF) in the clinic. Objective: To investigate TRBF in eyes with DR of varying severity, with or without diabetic macular edema (DME), using en face Doppler OCT...
February 9, 2017: JAMA Ophthalmology
https://www.readbyqxmd.com/read/28194871/engineering-of-optically-encoded-microbeads-with-fret-free-spatially-separated-quantum-dot-layers-for-multiplexed-assays
#16
Igor Nabiev, Regina S Bilan, Viktor A Krivenkov, Mikhail A Berestovoy, Anton Efimov, Igor I Agapov, Pavel S Samokhvalov, Alyona V Sukhanova
Quantum dot (QD)-encoded microbeads are emerging for multiplexed analysis of biological markers. Quantitative encoding of the microbeads prepared with the different concentrations of QDs of different colors suffers from the resonance energy transfer from the QDs fluorescing at the shorter wavelengths to the QDs fluorescing at the longer wavelengths. Here, we have used the layer-by-layer deposition technique to spatially separate QDs of different colors with several polymer layers, so that the distance between them would be larger than the Förster energy transfer radius...
February 13, 2017: Chemphyschem: a European Journal of Chemical Physics and Physical Chemistry
https://www.readbyqxmd.com/read/28194836/quantitative-characterization-of-the-carbon-carbon-composites-components-based-on-video-of-polarized-light-microscope
#17
Yixian Li, Lehua Qi, Yongshan Song, Xujiang Chao
The components of carbon/carbon (C/C) composites have significant influence on the thermal and mechanical properties, so a quantitative characterization of component is necessary to study the microstructure of C/C composites, and further to improve the macroscopic properties of C/C composites. Considering the extinction crosses of the pyrocarbon matrix have significant moving features, the polarized light microscope (PLM) video is used to characterize C/C composites quantitatively because it contains sufficiently dynamic and structure information...
February 13, 2017: Microscopy Research and Technique
https://www.readbyqxmd.com/read/28193060/-bio-sensing-using-nanoparticle-arrays-on-the-effect-of-analyte-transport-on-sensitivity
#18
N Scott Lynn, Jiří Homola
There has recently been an extensive amount of work regarding the development of optical, electrical, and mechanical (bio)sensors employing planar arrays of surface-bound nanoparticles. The sensor output for these systems is dependent on the rate at which analyte is transported to, and interacts with, each nanoparticle in the array. There has so far been little discussion on the relationship between the design parameters of an array and the interplay of convection, diffusion, and reaction. Moreover, current methods providing such information require extensive computational simulation...
December 20, 2016: Analytical Chemistry
https://www.readbyqxmd.com/read/28193001/coalescence-sampling-and-analysis-of-aerosols-using-aerosol-optical-tweezers
#19
Allen E Haddrell, Rachael E H Miles, Bryan R Bzdek, Jonathan P Reid, Rebecca J Hopkins, Jim S Walker
We present a first exploratory study to assess the use of aerosol optical tweezers as an instrument for sampling and detecting accumulation- and coarse-mode aerosol. A subpicoliter aqueous aerosol droplet is captured in the optical trap and used as a sampling volume, accreting mass from a free-flowing aerosol generated by a medical nebulizer or atomizer. Real-time measurements of the initial stability in size, refractive index, and composition of the sampling droplet inferred from Raman spectroscopy confirm that these quantities can be measured with high accuracy and low noise...
February 9, 2017: Analytical Chemistry
https://www.readbyqxmd.com/read/28188853/drifting-while-stepping-in-place-in-old-adults-association-of-self-motion-perception-with-reference-frame-reliance-and-ground-optic-flow-sensitivity
#20
Catherine P Agathos, Delphine Bernardin, Konogan Baranton, Christine Assaiante, Brice Isableu
Optic flow provides visual self-motion information and is shown to modulate gait and provoke postural reactions. We have previously reported an increased reliance on the visual, as opposed to the somatosensory-based, egocentric frame of reference (FoR) for spatial orientation with age. In this study, we evaluated FoR reliance for self-motion perception with respect to the ground surface. We examined how effects of ground optic flow direction on posture may be enhanced by an intermittent podal contact with the ground, and reliance on the visual FoR and aging...
February 7, 2017: Neuroscience
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