scholarly journals Polypyrrole/Agarose Hydrogel-Based Bladder Volume Sensor with a Resistor Ladder Structure

Sensors ◽  
2018 ◽  
Vol 18 (7) ◽  
pp. 2288 ◽  
Author(s):  
Mi Kim ◽  
Sungwoo Lee ◽  
Inug Yoon ◽  
Geon Kook ◽  
Yeon Jung ◽  
...  
Keyword(s):  
Bladder Wall ◽  
Urine Volume ◽  
Bladder Volume ◽  
Continuous Mode ◽  
Ladder Structure ◽  
Sensing Mechanism ◽  
Mode Operation ◽  
Agarose Hydrogel ◽  
Ladder Network ◽  
Bladder Activity

Chronic monitoring of bladder activity and urine volume is essential for patients suffering from urinary dysfunctions. However, due to the anatomy and dynamics of the bladder, chronic and precise monitoring of bladder activity remains a challenge. Here, we propose a new sensing mechanism that measures the bladder volume using a resistive ladder network with contact switches. Instead of measuring the impedance between the electrode continuously, the proposed sensor provides a digitized output (‘on’ or ‘off’) when the bladder volume reaches a certain threshold value. We present simple proof-of-concept sensors which compare the discrete-mode operation to the continuous-mode operation. In addition, by using multiple pairs of this contact-mode switch in a resistor ladder structure, we demonstrate monitoring of the bladder volume in four discrete steps using an idealized balloon and an ex vivo pig’s bladder. We implemented the resistive ladder network using a conductive polypyrrole/agarose hydrogel composite which exhibits a Young’s modulus comparable to that of the bladder wall. Compared to the continuous-mode operation, the proposed sensing mechanism is less susceptible to drift due to material degradation and environmental factors.

Continuous-mode operation of a noiseless linear amplifier

2016 ◽  
Vol 93 (5) ◽  
Author(s):  
Yi Li ◽  
André R. R. Carvalho ◽  
Matthew R. James
Keyword(s):  
Continuous Mode ◽  
Mode Operation ◽  
Linear Amplifier

Continuous mode operation of a PRIZ space-time light modulator

1990 ◽  
Author(s):  
T. J. Tayag ◽  
James J. Sluss, Jr. ◽  
Theodore E. Batchman
Keyword(s):  
Space Time ◽  
Continuous Mode ◽  
Light Modulator ◽  
Mode Operation

scholarly journals Determination of log removal values of bacteria by spiral-wound reverse osmosis modules and a hollow fiber ultrafiltration module using Escherichia coli and indigenous heterotrophic bacteria as indicators

2020 ◽  
Vol 18 (6) ◽  
pp. 956-967
Author(s):  
Yumiko Ohkouchi ◽  
Tomonobu Ase
Keyword(s):  
Escherichia Coli ◽  
Reverse Osmosis ◽  
Hollow Fiber ◽  
Heterotrophic Bacteria ◽  
Operation Mode ◽  
Continuous Mode ◽  
E Coli ◽  
Mode Operation ◽  
Wide Range ◽  
Spiral Wound

Abstract The use of reverse osmosis (RO) membranes has been expanding not only to medical applications but also to water supply and reclaimed water applications due to its strong ability to remove a wide range of contaminants. Many researchers reported RO performance as a barrier against waterborne viruses; however, there are limited reports on its ability to remove bacteria from water. This investigation evaluated the removal performances of several spiral-wound RO modules and a hollow fiber ultrafiltration (UF) module in two different ways: dosing tests in batch-wise mode operation and in continuous-mode operation. The dosing tests of Escherichia coli using RO modules confirmed that E. coli could leak from the feed-side into the permeate. The log removal values (LRVs) (4.21- to >7.44-log10) by the RO modules from different production lots were found to vary greatly. In continuous-mode operation of the RO module, the LRVs for indigenous heterotrophic bacteria decreased over the operation period. These results clearly illustrate that bacteria, which originate on the feed-side, can leak into the permeate-side and then begin to proliferate in the permeate. On the other hand, using a UF module, E. coli was not detected in the permeate regardless of the operation mode.

scholarly journals Comparison Of Urinary Bladder Volume In Children Using Suprapubic Ultrasonic Bi-Planner Technique With Voided Urine Volume

2012 ◽  
Vol 17 (2) ◽  
pp. 4-7
Author(s):  
S Sadek ◽  
M Hossain ◽  
H Akther ◽  
A Sikdar
Keyword(s):  
Real Time ◽  
Accurate Determination ◽  
Urine Volume ◽  
Bladder Capacity ◽  
Bladder Volume ◽  
Bladder Function ◽  
Urethral Trauma ◽  
Fear And Anxiety ◽  
Real Time Ultrasonography

Accurate determination of intravesical residual urine volume as well as bladder capacity is of significant importance in children. The ability to confirm these measurements non invasively in children avoids discomfort, urethral trauma and the introduction of urinary tract infection. Also, by avoiding the need for catheterization this technique permits more physiological assessment and allows for repeated examinations without fear and anxiety on the part of the patients. In this prospective study we assess the accuracy of the real time, hand held, ultrasonic device using suprapubic views and biplanar technique to determine intravesical volumes. Real time ultrasonography with suprapubic views and the described bi-planar technique to determine intravesical urine volume is simple, accurate and reproducible. It also is rapid and noninvasive, and can detect accurately an empty bladder in children. A strong correlation was found between the estimated bladder volume with our method and voided urine volume (0 ml, residual volume) .This study concluded that the modality used in this study has the potential to provide useful and reproducible information in the clinical evaluation of bladder function in children.DOI: http://dx.doi.org/10.3329/jdnmch.v17i2.12199 J. Dhaka National Med. Coll. Hos. 2011; 17 (02): 4-7

scholarly journals Functional and histologic imaging of urinary bladder wall after exposure to psychological stress and protamine sulfate

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Tetsuichi Saito ◽  
T. Kevin Hitchens ◽  
Lesley M. Foley ◽  
Nishant Singh ◽  
Shinsuke Mizoguchi ◽  
...  
Keyword(s):  
Relaxation Time ◽  
Urinary Bladder ◽  
Psychological Stress ◽  
Bladder Wall ◽  
Urine Volume ◽  
Protamine Sulfate ◽  
Control Group ◽  
Post Contrast ◽  
Urinary Bladder Wall ◽  
Nocturnal Urination

AbstractTo quantify the urinary bladder wall T1 relaxation time (T1) before and after the instillation contrast mixture in rats previously subjected to water avoidance stress (WAS) and/or acute exposure to protamine sulfate (PS). Female Wistar rats were randomized to receive either sham (control) or 1 h of WAS for ten consecutive days before the evaluation of nocturnal urination pattern in metabolic cages. T1 mapping of urinary bladder wall at 9.4 T was performed pre- and post- instillation of 4 mM Gadobutrol in a mixture with 5 mM Ferumoxytol. Subsequently, either T1 mapping was repeated after brief intravesical PS exposure or the animals were sacrificed for histology and analyzing the mucosal levels of mRNA. Compared to the control group, WAS exposure decreased the single void urine volume and shortened the post-contrast T1 relaxation time of mucosa- used to compute relatively higher ingress of instilled Gadobutrol. Compromised permeability in WAS group was corroborated by the urothelial denudation, edema and ZO-1 downregulation. PS exposure doubled the baseline ingress of Gadobutrol in both groups. These findings confirm that psychological stress compromises the paracellular permeability of bladder mucosa and its non-invasive assay with MRI was validated by PS exposure.

scholarly journals PHYSIOLOGICAL CAUSES FOR THE VARIED CHARACTER OF STASIS BILE

1921 ◽  
Vol 34 (1) ◽  
pp. 75-95 ◽  
Author(s):  
Peyton Rous ◽  
Philip D. McMaster
Keyword(s):  
Specific Gravity ◽  
Gall Bladder ◽  
Functional Activity ◽  
Bladder Wall ◽  
Clinical Consequences ◽  
Bladder Activity ◽  
Biliary Stasis ◽  
White Bile ◽  
The One ◽  
Considerable Pressure

The gall bladder and ducts exert opposite influences upon the bile. The ducts fail to concentrate and thicken it with mucus as the bladder does, but dilute it slightly with a thin secretion of their own that is colorless and devoid of cholates even when the organism is heavily jaundiced. The fluid may readily be collected into a rubber bag connected with an isolated duct segment. It continues to be formed against a considerable pressure, and, in the dog, is slightly alkaline to litmus, clear, almost watery, practically devoid of cholesterol, and of low specific gravity to judge from the one specimen tested. In obstructed ducts separated from the gall bladder, or connecting with one so changed pathologically that the concentrating faculty has been lost, such fluid gradually replaces the small amount of bile originally pent up. It is the so called "white bile" of surgeons. When obstructed ducts connect with an approximately normal gall bladder the stasis fluid is entirely different, owing to the bladder activity. At first there accumulates in quantity a true bile much inspissated by loss of fluid through the bladder wall, darkened by a change in the pigment, and progressively thickened with bladder mucus. As time passes duct secretion mingles with the tarry accumulation and very gradually replaces it. The inspissation of the bile, as indicated by the pigment content, is at its greatest after only a day or two of stasis. The differing influences of the ducts and bladder upon the bile must obviously have much to do with the site of origin of calculi and their clinical consequences. The concentrating activity of the bladder cannot but be a potent element in the formation of stones. We have discussed these matters at some length. Intermittent biliary stasis is admittedly the principal predisposing cause of cholelithiasis; and the stasis is to be thought of as effective, in many instances at least, through the excessive biliary inspissation for which it gives opportunity. In this way a normal gall bladder can become, merely through functional activity, a menace to the organism. In patients with the tendency to stones frequent feedings may lessen the danger of their formation.

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