keyword
MENU ▼
Read by QxMD icon Read
search

Speckle

keyword
https://www.readbyqxmd.com/read/27921165/left-ventricular-twist-mechanics-during-incremental-cycling-and-knee-extension-exercise-in-healthy-men
#1
Alexander Beaumont, John Hough, Nicholas Sculthorpe, Joanna Richards
PURPOSE: The objective of the present study was to investigate left ventricular (LV) twist mechanics in response to incremental cycling and isometric knee extension exercises. METHODS: Twenty-six healthy male participants (age = 30.42 ± 6.17 years) were used to study peak twist mechanics at rest and during incremental semi-supine cycling at 30 and 60% work rate maximum (W max) and during short duration (15 s contractions) isometric knee extension at 40 and 75% maximum voluntary contraction (MVC), using two-dimensional speckle tracking echocardiography...
December 5, 2016: European Journal of Applied Physiology
https://www.readbyqxmd.com/read/27916858/three-dimensional-continuous-displacement-measurement-with-temporal-speckle-pattern-interferometry
#2
Jie Qin, Zhan Gao, Xu Wang, Shanwei Yang
A speckle interferometer which can measure whole field three-dimensional displacements continuously and dynamically has been built. Three different wavelength lasers are used to produce the speckle interferograms of the two in-plane displacements (displacements in the x- and y-direction) and one out-of-plane displacement (displacement in the z-direction), respectively. One color CCD camera is employed to collect these mixed speckle interferograms simultaneously. The mixed interferograms are separated by the Red, Green and Blue channels of the color CCD camera, and then are processed by the wavelet transform technique to extract the phase information of the measured object...
November 29, 2016: Sensors
https://www.readbyqxmd.com/read/27916237/transesophageal-speckle-tracking-echocardiography-improves-right-ventricular-systolic-function-assessment-in-the-perioperative-setting
#3
Nicholas W Markin, Mohammed Chamsi-Pasha, Jiangtao Luo, Walker R Thomas, Tara R Brakke, Thomas R Porter, Sasha K Shillcutt
BACKGROUND: Perioperative evaluation of right ventricular (RV) systolic function is important to follow intraoperative changes, but it is often not possible to assess with transthoracic echocardiographic (TTE) imaging, because of surgical field constraints. Echocardiographic RV quantification is most commonly performed using tricuspid annular plane systolic excursion (TAPSE), but it is not clear whether this method works with transesophageal echocardiographic (TEE) imaging. This study was performed to evaluate the relationship between TTE and TEE TAPSE distances measured with M-mode imaging and in comparison with speckle-tracking TTE and TEE measurements...
December 1, 2016: Journal of the American Society of Echocardiography
https://www.readbyqxmd.com/read/27916236/strain-imaging-with-a-bull-s-eye-map-for-detecting-significant-coronary-stenosis-during-dobutamine-stress-echocardiography
#4
Li-Tan Yang, Yuichiro Kado, Yasufumi Nagata, Kyoko Otani, Yutaka Otsuji, Masaaki Takeuchi
BACKGROUND: Accurate visual assessment of wall motion during dobutamine stress echocardiography (DSE) requires expertise; strain stress echocardiography thus has potential for the objective and reliable evaluation of stress-induced wall motion abnormalities. The aim of this study was to test the hypothesis that strain imaging also requires expertise. Diagnostic accuracy for significant coronary artery disease was compared between visual and strain analysis with a bull's-eye map, and the effect of expertise on readers' accuracy during DSE was determined...
December 1, 2016: Journal of the American Society of Echocardiography
https://www.readbyqxmd.com/read/27912199/right-ventricular-dyssynchrony-predicts-clinical-outcomes-in-patients-with-pulmonary-hypertension
#5
Mitsushige Murata, Toshimitsu Tsugu, Takashi Kawakami, Masaharu Kataoka, Yugo Minakata, Jin Endo, Hikaru Tsuruta, Yuji Itabashi, Yuichiro Maekawa, Keiichi Fukuda
BACKGROUND: RV dyssynchrony has been described in patients with pulmonary hypertension (PH) and is an independent predictor of clinical worsening; however, the optimal method for measuring RV dyssynchrony has not been fully established. This study aimed to investigate whether RV dyssynchrony is correlated with hemodynamics and prognosis in PH patients and to identify the best parameter for evaluating RV dyssynchrony. METHODS: This study assessed 100 PH patients, measuring mean pulmonary artery pressure (mPAP), pulmonary vascular resistance (PVR), and cardiac index (CI) by right heart catheterization (RHC)...
November 14, 2016: International Journal of Cardiology
https://www.readbyqxmd.com/read/27910996/speckle-tracking-echocardiography-predicts-early-subclinical-anthracycline-cardiotoxicity-in-patients-with-breast-cancer
#6
Qi Tang, Yan Jiang, Yali Xu, Hongmei Xia
PURPOSE: This study aimed to assess the early changes of left ventricular (LV) and right ventricular (RV) mechanics associated with anthracycline treatment for breast cancer and to determine whether two-dimensional speckle tracking echocardiography (2D-STE) analysis could predict chemotherapy-induced cardiotoxicity. BACKGROUND: Anthracycline generates progressive LV dysfunction associated with a poor prognosis. Early detection of minor change of myocardial mechanics is thus important...
December 2, 2016: Journal of Clinical Ultrasound: JCU
https://www.readbyqxmd.com/read/27909859/sofa-score-and-left-ventricular-systolic-function-as-predictors-of-short-term-outcome-in-patients-with-sepsis
#7
Francesca Innocenti, Vittorio Palmieri, Aurelia Guzzo, Valerio Teodoro Stefanone, Chiara Donnini, Riccardo Pini
In a group of septic patients, we assess the short-term prognostic value of LV systolic performance, evaluated through conventional left ventricular ejection fraction (LVEF) and left ventricular global longitudinal strain (LV GLS). One hundred forty-seven patients with sepsis were recruited; LVEF by planimetry and peak GLS by 2D speckle tracking could be assessed within 24 h. The study population was stratified according to SOFA tertiles assessed at the time of the echocardiogram (G1: SOFA score <5; G2: SOFA score 5-7; G3: SOFA score >7)...
December 1, 2016: Internal and Emergency Medicine
https://www.readbyqxmd.com/read/27909265/prevention-of-the-collapse-of-pial-collaterals-by-remote-ischemic-perconditioning-during-acute-ischemic-stroke
#8
Junqiang Ma, Yonglie Ma, Bin Dong, Mischa V Bandet, Ashfaq Shuaib, Ian R Winship
Collateral circulation is a key variable determining prognosis and response to recanalization therapy during acute ischemic stroke. Remote ischemic perconditioning (RIPerC) involves inducing peripheral ischemia (typically in the limbs) during stroke and may reduce perfusion deficits and brain damage due to cerebral ischemia. In this study, we directly investigated pial collateral flow augmentation due to RIPerC during distal middle cerebral artery occlusion (MCAo) in rats. Blood flow through pial collaterals between the anterior cerebral artery (ACA) and the MCA was assessed in male Sprague Dawley rats using in vivo laser speckle contrast imaging (LSCI) and two photon laser scanning microscopy (TPLSM) during distal MCAo...
December 1, 2016: Journal of Cerebral Blood Flow and Metabolism
https://www.readbyqxmd.com/read/27908646/left-ventricular-function-in-healthy-term-neonates-during-the-transitional-period
#9
Amish Jain, Afif F El-Khuffash, Bart C W Kuipers, Adel Mohamed, Kim A Connelly, Patrick J McNamara, Robert P Jankov, Luc Mertens
OBJECTIVES: To evaluate whether incorporating conventional, tissue Doppler imaging and speckle tracking echocardiography are reliable and can characterize changes in left ventricular (LV) function properly in healthy neonates in the early transitional newborn period. STUDY DESIGN: A prospective observational study was conducted in 50 healthy term neonates with a mean ± SD gestational age and birth weight of 39.3 ± 1.2 weeks and 3.5 ± 0.44 kg, respectively...
November 28, 2016: Journal of Pediatrics
https://www.readbyqxmd.com/read/27906702/diagnostic-accuracy-of-intraluminal-blood-speckle-intensity-on-intravascular-ultrasound-for-physiological-assessment-of-coronary-artery-stenosis
#10
Yuichi Saito, Hideki Kitahara, Takashi Nakayama, Yoshihide Fujimoto, Yoshio Kobayashi
OBJECTIVES: The difference in intraluminal intensity of blood speckle (IBS) on integrated backscatter intravascular ultrasound (IVUS) across the coronary stenosis was reportedly correlated with fractional flow reserve (FFR) in the left descending coronary artery. The aim of this study was to investigate the novel physiological assessment using IVUS in all coronary arteries. PATIENTS AND METHODS: Fifty-four patients with 57 coronary lesions underwent both FFR and IVUS...
November 30, 2016: Coronary Artery Disease
https://www.readbyqxmd.com/read/27906373/efficient-homogeneous-illumination-and-optical-sectioning-for-quantitative-single-molecule-localization-microscopy
#11
Joran Deschamps, Andreas Rowald, Jonas Ries
Single-molecule localization microscopy (SMLM) relies on the switching of fluorescent molecules between a fluorescent and a dark state to achieve super resolution. This process is inherently dependent on the intensity distribution of the laser light used for both activation from the dark state and excitation of the bright state. Typically, laser light is coupled directly or via a single-mode fiber into the microscope, which leads to a Gaussian intensity profile in total internal reflection (TIR) or epi illumination...
November 28, 2016: Optics Express
https://www.readbyqxmd.com/read/27906359/monitoring-blood-vital-bio-signs-using-secondary-speckle-patterns
#12
Talia Sirkis, Yevgeny Beiderman, Sergey Agdarov, Yafim Beiderman, Zeev Zalevsky
Continuous noninvasive measurement of vital bio-signs, such as cardiopulmonary parameters, is an important tool in the evaluation process of the patient's physiological condition and in the health monitoring of the patient. On the demand of new enabling technologies, some works have been done in continuous monitoring of blood pressure and pulse wave velocity. In this paper, we introduce further application of a novel technique for remote noncontact blood pulse wave velocity and pressure measurement based on tracking the temporal changes of reflected secondary speckle patterns produced in human skin when illuminated by a laser beam...
November 28, 2016: Optics Express
https://www.readbyqxmd.com/read/27906358/monitoring-blood-vital-bio-signs-using-secondary-speckle-patterns
#13
Talia Sirkis, Yevgeny Beiderman, Sergey Agdarov, Yafim Beiderman, Zeev Zalevsky
Continuous noninvasive measurement of vital bio-signs, such as cardiopulmonary parameters, is an important tool in the evaluation process of the patient's physiological condition and in the health monitoring of the patient. On the demand of new enabling technologies, some works have been done in continuous monitoring of blood pressure and pulse wave velocity. In this paper, we introduce further application of a novel technique for remote noncontact blood pulse wave velocity and pressure measurement based on tracking the temporal changes of reflected secondary speckle patterns produced in human skin when illuminated by a laser beam...
November 28, 2016: Optics Express
https://www.readbyqxmd.com/read/27906296/numerical-modeling-of-fiber-specklegram-sensors-by-using-finite-element-method-fem
#14
V H Arístizabal, F J Vélez, E Rueda, N D Gómez, J A Gómez
Although experimental advances in the implementation and characterization of fiber speckle sensor have been reported, a suitable model to interpret the speckle-pattern variation under perturbation is desirable but very challenging to be developed due to the various factors influencing the speckle pattern. In this work, a new methodology based on the finite element method (FEM) for modeling and optimizing fiber specklegram sensors (FSSs) is proposed. The numerical method allows computational visualization and quantification, in near field, of changes of a step multi-mode fiber (SMMF) specklegram, due to the application of a uniformly distributed force line (UDFL)...
November 28, 2016: Optics Express
https://www.readbyqxmd.com/read/27906262/light-field-and-holographic-three-dimensional-displays-invited
#15
Masahiro Yamaguchi
A perfect three-dimensional (3D) display that satisfies all depth cues in human vision is possible if a light field can be reproduced exactly as it appeared when it emerged from a real object. The light field can be generated based on either light ray or wavefront reconstruction, with the latter known as holography. This paper first provides an overview of the advances of ray-based and wavefront-based 3D display technologies, including integral photography and holography, and the integration of those technologies with digital information systems...
December 1, 2016: Journal of the Optical Society of America. A, Optics, Image Science, and Vision
https://www.readbyqxmd.com/read/27906220/noise-analysis-of-speckle-based-x-ray-phase-contrast-imaging
#16
Tunhe Zhou, Marie-Christine Zdora, Irene Zanette, Jenny Romell, Hans M Hertz, Anna Burvall
Speckle-based x-ray phase-contrast imaging has drawn increasing interest in recent years as a simple, multimodal, cost-efficient, and laboratory-source adaptable method. We investigate its noise properties to help further optimization on the method and further comparison with other phase-contrast methods. An analytical model for assessing noise in a differential phase signal is adapted from studies on the digital image correlation technique in experimental mechanics and is supported by simulations and experiments...
December 1, 2016: Optics Letters
https://www.readbyqxmd.com/read/27906075/nuclear-bodies-reorganize-during-myogenesis-in-vitro-and-are-differentially-disrupted-by-expression-of-fshd-associated-dux4
#17
Sachiko Homma, Mary Lou Beermann, Bryant Yu, Frederick M Boyce, Jeffrey Boone Miller
BACKGROUND: Nuclear bodies, such as nucleoli, PML bodies, and SC35 speckles, are dynamic sub-nuclear structures that regulate multiple genetic and epigenetic processes. Additional regulation is provided by RNA/DNA handling proteins, notably TDP-43 and FUS, which have been linked to ALS pathology. Previous work showed that mouse cell line myotubes have fewer but larger nucleoli than myoblasts, and we had found that nuclear aggregation of TDP-43 in human myotubes was induced by expression of DUX4-FL, a transcription factor that is aberrantly expressed and causes pathology in facioscapulohumeral dystrophy (FSHD)...
December 1, 2016: Skeletal Muscle
https://www.readbyqxmd.com/read/27905494/laser-speckle-rheology-for-evaluating-the-viscoelastic-properties-of-hydrogel-scaffolds
#18
Zeinab Hajjarian, Hadi Tavakoli Nia, Shawn Ahn, Alan J Grodzinsky, Rakesh K Jain, Seemantini K Nadkarni
Natural and synthetic hydrogel scaffolds exhibit distinct viscoelastic properties at various length scales and deformation rates. Laser Speckle Rheology (LSR) offers a novel, non-contact optical approach for evaluating the frequency-dependent viscoelastic properties of hydrogels. In LSR, a coherent laser beam illuminates the specimen and a high-speed camera acquires the time-varying speckle images. Cross-correlation analysis of frames returns the speckle intensity autocorrelation function, g2(t), from which the frequency-dependent viscoelastic modulus, G*(ω), is deduced...
December 1, 2016: Scientific Reports
https://www.readbyqxmd.com/read/27900955/serum-levels-of-n-terminal-pro-b-type-natriuretic-peptide-as-a-diagnostic-marker-for-left-ventricular-dysfunction-in-children-with-end-stage-renal-disease-on-hemodialysis
#19
Amr Mohamed Zoair, Maher Ahmed Abdel-Hafez, Wegdan Mawlana, Mohamed Abdel-Rahman Sweylam
The objective of this study was to determine the diagnostic cutoff value of N-terminal-pro B-type natriuretic peptide (NT-pro BNP) as a marker of left ventricular (LV) dysfunction in children with end-stage renal disease (ESRD) on regular hemodialysis (HD). The study was carried out on thirty children with ESRD on regular HD and thirty healthy controls. Echocardiographic studies were done, including a conventional mode for ejection fraction, fractional shortening, tissue Doppler imaging, and longitudinal global strain by speckle tracking...
November 2016: Saudi Journal of Kidney Diseases and Transplantation
https://www.readbyqxmd.com/read/27900535/evaluation-of-cerebral-circulation-during-retrograde-perfusion-by-laser-speckle-flowgraphy
#20
Fumiaki Kimura, Hirotsugu Kanda, Yuki Toyama, Takayuki Kunisawa, Taiji Nagaoka, Akitoshi Yoshida, Hiroto Kitahara, Hiroyuki Kamiya
Laser speckle flowgraphy (LSFG) is an ophthalmologic equipment that qualitatively detects the blood flow of the optic nerve head, which is known to be related with cerebral microcirculation. LSFG can also measure the mean blur rate, which quantitatively calculates the blood flow. We aimed to assess the utility of LSFG in the evaluation of cerebral perfusion during aortic surgery under hypothermic circulatory arrest with retrograde and antegrade cerebral perfusion. Two patients underwent total arch replacement for aneurysm...
November 29, 2016: General Thoracic and Cardiovascular Surgery
keyword
keyword
112895
1
2
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"