Excess Scattered-Light Intensity Fluctuations from Hemoglobin

1974 ◽  
Vol 32 (2) ◽  
pp. 37-40 ◽  
Author(s):  
E. E. Uzgiris ◽  
D. C. Golibersuch
Keyword(s):  
Light Intensity ◽  
Scattered Light ◽  
Scattered Light Intensity ◽  
Intensity Fluctuations

scholarly journals Scattered-light intensity fluctuations in diastolic rat cardiac muscle caused by spontaneous Ca++-dependent cellular mechanical oscillations.

1983 ◽  
Vol 82 (1) ◽  
pp. 119-153 ◽  
Author(s):  
M D Stern ◽  
A A Kort ◽  
G M Bhatnagar ◽  
E G Lakatta
Keyword(s):  
Light Intensity ◽  
Cardiac Muscle ◽  
Scattered Light ◽  
Photon Counting ◽  
Force Production ◽  
Intrinsic Property ◽  
Physiological Saline ◽  
Scattered Light Intensity ◽  
Mechanical Oscillations ◽  
Intensity Fluctuations

Laser light scattered by nonstimulated rat cardiac muscle bathed in physiological saline containing a [Ca++] of 0.4-2.5 mM displays scattered-light intensity fluctuations (SLIF); the frequencies of both SLIF and resting force are Ca++ dependent. Direct inspection of these muscles by phase-contrast microscopy under incoherent illumination revealed the presence of spontaneous asynchronous cellular motions that are also Ca++ dependent. The physical properties of the scattered light are compatible with the hypothesis that SLIF are due to the diastolic motion, except for the dependence on scattering angle, which may be perturbed because the muscles are optically thick. To determine whether diastolic SLIF and motion are an intrinsic property of activated myofilaments, photon-counting auto-correlation of the scattered light was performed both in rat right-ventricular papillary muscles skinned with the detergent Triton X-100 (1%) and in muscles with intact membranes under conditions that alter cellular Ca++ fluxes. In skinned muscles activated over a range of Ca++ from threshold to maximum force production, neither SLIF nor asynchronous motion was observed when Ca++ was buffered to constant values. In intact muscles the frequency of SLIF and the amplitude of diastolic motion were (a) markedly increased by substituting K+ or Li+ for Na+ in the bath; (b) not altered by verapamil (1 microM); and (c) reversibly abolished by caffeine (greater than or equal to 10 mM). These properties are exactly those of mechanical oscillations that have been observed in isolated cardiac cell fragments, which are the result Ca++ oscillations caused by Ca++ release from the sarcoplasmic reticulum (SR). We infer that mechanical oscillations caused by spontaneous Ca++-induced Ca++ release from the SR occur in intact nonstimulated cardiac muscle even in the absence of Ca++ overload and are the principle cause of SLIF, and that myoplasmic [Ca++] in "resting" muscle is not in a microscopic steady state.

scholarly journals Planar droplet sizing: Application to a spray of Jet A1 kerosene

2017 ◽  
Author(s):  
Pierre Doublet ◽  
Christine Lempereur ◽  
Virginel Bodoc ◽  
Mikael Orain ◽  
Pierre Gajan
Keyword(s):  
Light Intensity ◽  
Scattered Light ◽  
Droplet Surface ◽  
Scattered Light Intensity ◽  
Field Of View ◽  
Fluorescence Signal ◽  
Droplet Volume ◽  
Image Processing Algorithm ◽  
Two Phase ◽  
Scattering Angle

Optical techniques are  widely employed for their non-intrusive behavior and are applied to two-phase flowinvestigations. Until now, the most commonly used technique to determine the droplet size is the Phase Doppler Anemogranulometry, although it is time consuming for an overall injector characterization. An imaging technique called Planar Droplet Sizing has been used to offer an alternative and provide a spatially-resolved 2D map of the Sauter Mean Diameter (SMD). The measurement is based on the ratio between laser-induced fluorescence and scattered light intensities which are assumed to be proportional respectively to the droplet volume and droplet surface area. However, previous studies revealed that the dependence of fluorescence intensity on the droplet volume can be altered by the absorption of light in the liquid. The scattered light intensity depends on the scattering angle and intensity variations within the field of view must be avoided.The aim of this study is to make the PDS technique operational for a Jet A-1 kerosene spray. A strong absorption of liquid kerosene appears under UV excitation at 266 nm making the technique unsuitable. Under visible excitation at 532 nm, a fluorescent tracer (Pyrromethene 597) must be added to the kerosene to enhance the fluorescence signal. To prevent scattered light intensity variations within the field of view, an optimal scattering angle close to 115° is required. An image processing algorithm is proposed in order to reduce the effects ofmultiple scattering.DOI: http://dx.doi.org/10.4995/ILASS2017.2017.4698

scholarly journals Method for the Determination of Density and Phase Functions of Interplanetary Dust

1980 ◽  
Vol 90 ◽  
pp. 55-60
Author(s):  
A. Mujica ◽  
G. Lôpez ◽  
F. Sánchez
Keyword(s):  
Light Intensity ◽  
Unit Volume ◽  
Interplanetary Space ◽  
Scattered Light ◽  
Interplanetary Dust ◽  
Scattered Light Intensity ◽  
Zodiacal Light ◽  
Method Of Determination ◽  
Phase Functions

SummaryA method of determination of the scattered light intensity, , by a unit-volume of interplanetary space is presented. From ground base Zodiacal Light measurements and the experimental results of Pioneer X the density, ρ(r), and phase, σ(θ), functions are obtained without any previous assumptions about them.

Correlation between Powder in the Plasma and Stability of High Rate Deposited a-Si:H

2005 ◽  
Vol 862 ◽  
Author(s):  
Guozhen Yue ◽  
Gautam Ganguly ◽  
Baojie Yan ◽  
Jeffrey Yang ◽  
Subhendu Guha
Keyword(s):  
Solar Cells ◽  
Light Intensity ◽  
Scattered Light ◽  
Scattered Light Intensity ◽  
High Rate ◽  
Invasive Technique ◽  
High Deposition Rate ◽  
Very High Frequency ◽  
Silicon Photodiode ◽  
Non Invasive

AbstractHydrogenated amorphous silicon (a-Si:H) solar cells incorporating high deposition rate (8-10Å/s) intrinsic layers were deposited using modified very high frequency (MVHF) plasma. We have monitored the light scattered from powder generated in the plasma using an Ar-laser and a silicon photodiode. This simple, non-invasive technique allows us to make measurements on the same reactor used to make the solar cells. First, we have varied the total flow rate and observed a maximum in the scattered light intensity from powder in the plasma during the deposition of the intrinsic layer, and correlated this with the degradation, as well as the stabilized performance of the solar cells. Then, we have studied the effects of varying the deposition temperature and/or the addition of germane to the gas mixture on the scattered light intensity due to powder in the plasma.

scholarly journals Optimum Angles for Multi-Angle Elastic Light Scattering Experiments

2011 ◽  
Author(s):  
D. W. Burr ◽  
K. J. Daun ◽  
K. A. Thomson ◽  
G. J. Smallwood
Keyword(s):  
Inverse Problem ◽  
Light Scattering ◽  
Light Intensity ◽  
Size Distribution ◽  
Design Of Experiment ◽  
Scattered Light ◽  
Scattered Light Intensity ◽  
Elastic Light Scattering ◽  
Optimal Angle ◽  
Ill Posed

In multiangle elastic light scattering (MAELS) experiments, the morphology of aerosolized particles is inferred by shining collimated radiation through the aerosol and then measuring the scattered light intensity over a set of angles. In the case of soot-laden aerosols MAELS can be used to recover, among other things, the size distribution of soot aggregates. This involves solving an ill-posed set of equations, however. While previous work focused on regularizing the inverse problem using Bayesian priors, this paper presents a design-of-experiment methodology for identifying the set of measurement angles that minimizes its ill-posedness. The inverse problem produced by the optimal angle set requires less regularization and is less sensitive to noise, compared with two other measurement angle sets commonly used to carry out MAELS experiments.

Opalescence and concentration fluctuations in binary liquid mixtures near the critical mixing point. - II. Theoretical

1954 ◽  
Vol 224 (1156) ◽  
pp. 104-119 ◽  
Keyword(s):  
Correlation Function ◽  
Light Intensity ◽  
Scattered Light ◽  
Wave Length ◽  
Liquid Mixtures ◽  
Density Fluctuations ◽  
Concentration Fluctuations ◽  
Scattered Light Intensity ◽  
Gaussian Shape ◽  
Critical Mixing

A theory of light scattering in fluids produced by local fluctuations of refractive index is developed from the theory of X-ray scattering in fluids which is applied to the phenomena of critical opalescence in one-component liquids due to density fluctuations and in two-component liquid mixtures due to concentration fluctuations. The dependence of the scattered light intensity on wave-length and scattering angle can be derived from the theoretical expressions when the correlation of the fluctuations in two volume elements as a function of the distance of these elements is known. The theory is used for determining the shape of the correlation function for a number of binary mixtures from the measured angular distribution of the scattered light intensity, as described in part I by means of numerical computation of Fourier integrals. It is found that the mixtures belonging to class I (as defined in part I) are characterized by a correlation function with a range of negative correlation, and those belonging to class II by a correlation function of nearly Gaussian shape. The absolute magnitude of the concentration fluctuations near the critical mixing point is also calculated from the observational material. A tentative qualitative explanation for the different shapes of the correlation function for the two classes of mixtures is presented.

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