scholarly journals Exploitation of blood non-Newtonian properties for ultrasonic measurement of hematocrit

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
B. Pialot ◽  
J. Gachelin ◽  
J. Provost ◽  
O. Couture
Keyword(s):  
Blood Velocity ◽  
Ultrasonic Measurement ◽  
Measurement Scale ◽  
Ultrasonic Signals ◽  
Ultrasound System ◽  
New Processing ◽  
Evaluation And Monitoring ◽  
Processing Techniques ◽  
Newtonian Behavior

AbstractNew processing techniques for manipulating blood and its components at a microfluidic scale are currently implemented. As for extracorporeal circulation, the in-line evaluation and monitoring of blood properties during these microfluidic techniques is a challenging task. Here, we show that the blood hematocrit can be measured non-invasively in a sub-millimeter medical tube using the non-Newtonian behavior of blood velocity profile. This hematocrit measurement is demonstrated on human blood with a simple Doppler ultrasound system. Results show a mean measurement error of 4.6 ± 1.3%Hct for hematocrit up to 52% and for 5 s-long ultrasonic signals. The simplicity and the measurement scale of the approach make it highly valuable for measuring hematocrit in new blood separation techniques. The approach may have an impact on in-vitro blood processing in general.

Specific Labeling of Protein Domains with Antibody Fragments

1981 ◽  
Vol 39 ◽  
pp. 416-417
Author(s):  
U. Aebi ◽  
L.E. Buhle ◽  
W.E. Fowler
Keyword(s):  
Image Processing ◽  
Specific Protein ◽  
Antibody Fragments ◽  
Supramolecular Organization ◽  
Two Dimensional ◽  
Ordered Structures ◽  
Virus Capsids ◽  
Processing Techniques

Many important supramolecular structures such as filaments, microtubules, virus capsids and certain membrane proteins and bacterial cell walls exist as ordered polymers or two-dimensional crystalline arrays in vivo. In several instances it has been possible to induce soluble proteins to form ordered polymers or two-dimensional crystalline arrays in vitro. In both cases a combination of electron microscopy of negatively stained specimens with analog or digital image processing techniques has proven extremely useful for elucidating the molecular and supramolecular organization of the constituent proteins. However from the reconstructed stain exclusion patterns it is often difficult to identify distinct stain excluding regions with specific protein subunits. To this end it has been demonstrated that in some cases this ambiguity can be resolved by a combination of stoichiometric labeling of the ordered structures with subunit-specific antibody fragments (e.g. Fab) and image processing of the electron micrographs recorded from labeled and unlabeled structures.

Prediction of Ultrasonic Signals Captured from a Side-Drilled Hole Using a Rectangular Transducer

2006 ◽  
Vol 321-323 ◽  
pp. 497-500
Author(s):  
Hak Joon Kim ◽  
Sung Jin Song ◽  
Lester W. Schmerr
Keyword(s):  
Reference Model ◽  
Measurement Model ◽  
Ultrasonic Measurement ◽  
Beam Model ◽  
System Efficiency ◽  
Ultrasonic Beam ◽  
Ultrasonic Signals ◽  
Measurement Results ◽  
Complete Measurement ◽  
Proper Interpretation

For the proper interpretation of ultrasonic measurement results from a side-drilled hole (SDH) using a rectangular transducer, it is very helpful to have a complete ultrasonic measurement model. A highly efficient ultrasonic beam model of a rectangular transducer and an accurate scattering model of a SDH are currently available. However, to develop such a complete measurement model, a reference model for the system efficiency factor is also needed. In this study a reference model suitable for a rectangular transducer is given and combined with existing models to develop a complete ultrasonic measurement model that can the predict ultrasonic signals from a SDH. Based on this model, we have calculated the ultrasonic signals from a SDH at different transducer orientations and compared the model-based predictions with experiments.

scholarly journals Structural Characterization andIn VitroAntioxidant Activity of Kojic Dipalmitate Loaded W/O/W Multiple Emulsions Intended for Skin Disorders

2015 ◽  
Vol 2015 ◽  
pp. 1-8 ◽  
Author(s):  
Maíra Lima Gonçalez ◽  
Diana Gleide Marcussi ◽  
Giovana Maria Fioramonti Calixto ◽  
Marcos Antonio Corrêa ◽  
Marlus Chorilli
Keyword(s):  
Antioxidant Activity ◽  
Safety Profile ◽  
Flow Behavior ◽  
Microscopic Analysis ◽  
Skin Disorders ◽  
Activity Assay ◽  
Multiple Emulsions ◽  
Lipophilic Antioxidant ◽  
Newtonian Behavior

Multiple emulsions (MEs) are intensively being studied for drug delivery due to their ability to load and increase the bioavailability of active lipophilic antioxidant, such as kojic dipalmitate (KDP). The aim of this study was to structurally characterize developed MEs by determining the average droplet size (Dnm) and zeta potential (ZP), performing macroscopic and microscopic analysis and analyzing their rheological behavior andin vitrobioadhesion. Furthermore, thein vitrosafety profile and antioxidant activity of KDP-loaded MEs were evaluated. The developed MEs showed a Dnm of approximately 1 micrometer and a ZP of −13 mV, and no change was observed in Dnm or ZP of the system with the addition of KDP. KDP-unloaded MEs exhibited ‘‘shear thinning’’ flow behavior whereas KDP-loaded MEs exhibited Newtonian behavior, which are both characteristic of antithixotropic materials. MEs have bioadhesion properties that were not influenced by the incorporation of KDP. The results showed that the incorporation of KDP into MEs improved the safety profile of the drug. Thein vitroantioxidant activity assay suggested that MEs presented a higher capacity for maintaining the antioxidant activity of KDP. ME-based systems may be a promising platform for the topical application of KDP in the treatment of skin disorders.

Neutrophil kinetics in rabbits during infusion of zymosan-activated plasma

1989 ◽  
Vol 67 (1) ◽  
pp. 88-95 ◽  
Author(s):  
C. M. Doerschuk ◽  
M. F. Allard ◽  
J. C. Hogg
Keyword(s):  
Relative Size ◽  
Pulmonary Sequestration ◽  
Blood Velocity ◽  
Pulmonary Capillaries ◽  
In Vitro Activation ◽  
The Complement System ◽  
Kinetics In Vivo ◽  
Neutrophil Kinetics

Complement activation in vivo produces neutropenia and pulmonary sequestration of neutrophils (PMNs) whereas in vitro activation increases PMN adherence and decreases PMN deformability. The present study examined PMN kinetics in vivo to determine if this sequestration was specific to the lung. Venous or arterial injections of radiolabeled PMNs were given to animals receiving infusions of zymosan-activated plasma (ZAP) or saline, and the PMN distribution was evaluated 10 min later. In control animals, the relative size of the marginated and circulating PMN pools was similar after venous or arterial injection and regional PMN retention increased as blood velocity slowed. ZAP infusion produced threefold increases in PMNs within pulmonary capillaries after venous injection and PMN retention was independent of blood velocity. After arterial injection, ZAP infusion produced PMN sequestration in all organs. Rigid (glutaraldehyde-fixed) PMNs injected into control rabbits showed increased lung recoveries similar to those of fresh PMNs injected into ZAP-treated rabbits. We conclude that activation of the complement system causes PMN sequestration in both the pulmonary and the systemic microvasculature and that the decrease in PMN deformability that occurs with activation of the PMN may be important in the genesis of PMN sequestration.

New Processing Techniques in Ultrasound Imaging Systems

1982 ◽  
pp. 177-193 ◽  
Author(s):  
G. F. Manes ◽  
C. Susini ◽  
P. Tortoli ◽  
C. Atzeni
Keyword(s):  
Ultrasound Imaging ◽  
Imaging Systems ◽  
New Processing ◽  
Processing Techniques
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