Emulsion and blood flow in microchannels of differently structure

2014 ◽  
Vol 10 ◽  
pp. 19-26 ◽  
Author(s):  
A.T. Akhmetov ◽  
A.A. Rakhimov ◽  
A.A. Valiev ◽  
R.R. Nigmatzyanova
Keyword(s):  
Blood Flow ◽  
Rheological Properties ◽  
Flow Pattern ◽  
Human Blood ◽  
General Property ◽  
Soft Lithography ◽  
Microfluidic Devices ◽  
Droplet Deformation ◽  
Traditional Methods ◽  
Dynamic Blocking

Hydrodynamic studies results are presented for O/W and W/O emulsions, biological dispersion as a human blood in microchannels obtained both by traditional methods and soft lithography ones. It’s shown that a general property of dispersions flow in microchannels is the dynamic blocking phenomenon. An analysis of blood and emulsion rheological properties is provided by data got with a precision rheometer. Experiments using microfluidic devices supported to detect droplet deformation during the dynamic blocking and an asymmetry of the dispersion flow pattern ina stepped constriction.

scholarly journals Pixel-by-Pixel Arterial Spin Labeling Blood Flow Pattern Variation Analysis for Discrimination of Rheumatoid Synovitis: A Pilot Study

2017 ◽  
Vol 16 (1) ◽  
pp. 78-83 ◽  
Author(s):  
Taro Sakashita ◽  
Tamotsu Kamishima ◽  
Hiroyuki Sugimori ◽  
Minghui Tang ◽  
Atsushi Noguchi ◽  
...  
Keyword(s):  
Blood Flow ◽  
Pilot Study ◽  
Flow Pattern ◽  
Arterial Spin Labeling ◽  
Spin Labeling ◽  
Variation Analysis ◽  
Blood Flow Pattern

Skin blood flow pattern in burns outcomes

Burns ◽  
2004 ◽  
Vol 30 (4) ◽  
pp. 312-316 ◽  
Author(s):  
P Barachini ◽  
G.M Vezzoni ◽  
C Palombo ◽  
F Franzoni ◽  
G Bigalli
Keyword(s):  
Blood Flow ◽  
Flow Pattern ◽  
Skin Blood Flow ◽  
Blood Flow Pattern

Chest compression efficacy of child resuscitators

2021 ◽  
Vol 13 (11) ◽  
pp. 448-455
Author(s):  
Tiffany Wai Shan Lau ◽  
Anthony Robert Lim ◽  
Kyra Anne Len ◽  
Loren Gene Yamamoto
Keyword(s):  
Blood Flow ◽  
Cardiopulmonary Resuscitation ◽  
Chest Compression ◽  
Minimum Weight ◽  
Success Rates ◽  
Compression Force ◽  
Chest Compressions ◽  
Traditional Methods ◽  
Video Review ◽  
Brief Training

Background: Chest compression efficacy determines blood flow in cardiopulmonary resuscitation (CPR) and relies on body mechanics, so resuscitator weight matters. Individuals of insufficient weight are incapable of generating a sufficient downward chest compression force using traditional methods. Aims: This study investigated how a resuscitator's weight affects chest compression efficacy, determined the minimum weight required to perform chest compressions and, for children and adults below this minimum weight, examine alternate means to perform chest compressions. Methods: Volunteers aged 8 years and above were enrolled to perform video-recorded, music-facilitated, compression-only CPR on an audible click-confirming manikin for 2 minutes, following brief training. Subjects who failed this proceeded to alternate modalities: chest compressions by jumping on the lower sternum; and squat-bouncing (bouncing the buttocks on the chest). These methods were assessed via video review. Findings: There were 57 subjects. The 30 subjects above 40kg were all able to complete nearly 200 compressions in 2 minutes. Success rates declined in those who weighed less than 40kg. Below 30 kg, only one subject (29.9 kg weight) out of 14 could achieve 200 effective compressions. Nearly all of the 23 subjects who could not perform conventional chest compressions were able to achieve effective chest compressions using alternate methods. Conclusion: A weight below 40kg resulted in a declining ability to perform standard chest compressions effectively. For small resuscitators, the jumping and squat-bouncing methods resulted in sufficient compressions most of the time; however, chest recoil and injuries are concerns.

Neonatal Intracranial Hemorrhage and Phenobarbital

PEDIATRICS ◽  
1987 ◽  
Vol 79 (2) ◽  
pp. 315-315
Author(s):  
KARL C. K. KUBAN ◽  
ELIZABETH BROWN ◽  
ALAN LEVITON ◽  
KALPATHY KRISHNAMOORTHY
Keyword(s):  
Risk Factors ◽  
Blood Flow ◽  
Cerebral Blood Flow ◽  
Flow Pattern ◽  
Intracranial Hemorrhage ◽  
Double Blind Study ◽  
Inclusion Criteria ◽  
Blood Flow Pattern ◽  
Double Blind ◽  
Ultrasound Testing

In Reply.— We appreciate the comments by Dr Battisti et al. As noted in the inclusion criteria for our study,1 all intubated babies with birth weights less than 1,751 g were eligible for the study. One of the advantages of a randomized double-blind study is that babies with other risk factors, including presence of a fluctuating cerebral blood flow pattern on Doppler ultrasound testing, should have equal chances of being in the treated and placebo groups.

scholarly journals Alterations of blood flow pattern after triple stent endovascular treatment of saccular abdominal aortic aneurysm: a porcine model.

2016 ◽  
Vol 43 (3) ◽  
pp. 154-159
Author(s):  
JAHIR RICHARD DE OLIVEIRA ◽  
MAURÍCIO DE AMORIM AQUINO ◽  
SVETLANA BARROS ◽  
GUILHERME BENJAMIN BRANDÃO PITTA ◽  
ADAMASTOR HUMBERTO PEREIRA
Keyword(s):  
Blood Flow ◽  
Abdominal Aortic Aneurysm ◽  
Aortic Aneurysm ◽  
Endovascular Treatment ◽  
Flow Pattern ◽  
Blood Flow Pattern ◽  
Large White ◽  
Abdominal Aortic ◽  
Before And After ◽  
Infrarenal Abdominal Aorta

ABSTRACT Objective: to determine the blood flow pattern changes after endovascular treatment of saccular abdominal aortic aneurysm with triple stent. Methods: we conducted a hemodynamic study of seven Landrace and Large White pigs with saccular aneurysms of the infrarenal abdominal aorta artificially produced according to the technique described. The animals were subjected to triple stenting for endovascular aneurysm. We evaluated the pattern of blood flow by duplex scan before and after stent implantation. We used the non-paired Mann-Whitney test for statistical analysis. Results: there was a significant decrease in the average systolic velocity, from 127.4cm/s in the pre-stent period to 69.81cm/s in the post-stent phase. There was also change in the flow pattern from turbulent in the aneurysmal sac to laminate intra-stent. Conclusion: there were changes in the blood flow pattern of saccular abdominal aortic aneurysm after endovascular treatment with triple stent.

A Very Low-Cost, Labor-Efficient, and Simple Method to Block Scattered Ultraviolet Light in PDMS Microfluidic Devices by Inserting Aluminum Foil Strips

2018 ◽  
Vol 11 (1) ◽  
Author(s):  
Shuo Wang ◽  
Peter Shankles ◽  
Scott Retterer ◽  
Yong Tae Kang ◽  
Chang Kyoung Choi
Keyword(s):  
Soft Lithography ◽  
Uv Light ◽  
Low Cost ◽  
Microfluidic Devices ◽  
Aluminum Foil ◽  
Material Synthesis ◽  
Simple Method ◽  
Micro Particles ◽  
Complex Shapes ◽  
The Cost

Abstract Opto-microfluidic methods have advantages for manufacturing complex shapes or structures of micro particles/hydrogels. Most of these microfluidic devices are made of polydimethylsiloxane (PDMS) by soft lithography because of its flexibility of designing and manufacturing. However, PDMS scatters ultraviolet (UV) light, which polymerizes the photocrosslinkable materials at undesirable locations and clogs the microfluidic devices. A fluorescent dye has previously been employed to absorb the scattered UV light and shift its wavelength to effectively solve this issue. However, this method is limited due to the cost of the materials (tens of dollars per microchip), the time consumed on synthesizing the fluorescent material and verifying its quality (two to three days). More importantly, significant expertise on material synthesis and characterization is required for users of the opto-microfluidic technique. The cost of preliminary testing on multiple iterations of different microfluidic chip designs would also be excessive. Alternatively, with a delicate microchannel design, we simply inserted aluminum foil strips (AFS) inside the PDMS device to block the scattered UV light. By using this method, the UV light was limited to the exposure region so that the opto-microfluidic device could consistently generate microgels longer than 6 h. This is a nearly cost- and labor-free method to solve this issue.

scholarly journals Micropipette-Based Microfluidic Device for Monodisperse Microbubbles Generation

Micromachines ◽  
2018 ◽  
Vol 9 (8) ◽  
pp. 387
Author(s):  
Carlos Toshiyuki Matsumi ◽  
Wilson José da Silva ◽  
Fábio Kurt Schneider ◽  
Joaquim Miguel Maia ◽  
Rigoberto E. M. Morales ◽  
...  
Keyword(s):  
Electric Fields ◽  
Microfluidic Device ◽  
Soft Lithography ◽  
Low Cost ◽  
Characteristic Curve ◽  
Microfluidic Devices ◽  
Average Diameter ◽  
Internal Diameter ◽  
Medical Diagnostic ◽  
Average Size

Microbubbles have various applications including their use as carrier agents for localized delivery of genes and drugs and in medical diagnostic imagery. Various techniques are used for the production of monodisperse microbubbles including the Gyratory, the coaxial electro-hydrodynamic atomization (CEHDA), the sonication methods, and the use of microfluidic devices. Some of these techniques require safety procedures during the application of intense electric fields (e.g., CEHDA) or soft lithography equipment for the production of microfluidic devices. This study presents a hybrid manufacturing process using micropipettes and 3D printing for the construction of a T-Junction microfluidic device resulting in simple and low cost generation of monodisperse microbubbles. In this work, microbubbles with an average size of 16.6 to 57.7 μm and a polydispersity index (PDI) between 0.47% and 1.06% were generated. When the device is used at higher bubble production rate, the average diameter was 42.8 μm with increased PDI of 3.13%. In addition, a second-order polynomial characteristic curve useful to estimate micropipette internal diameter necessary to generate a desired microbubble size is presented and a linear relationship between the ratio of gaseous and liquid phases flows and the ratio of microbubble and micropipette diameters (i.e., Qg/Ql and Db/Dp) was found.

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