On a Method for Increasing the Resolution of Atmospheric Pressure Measurements

(1) Background: The Adjustable Transobturator Male System (ATOMS) device is increasingly used to treat post-prostatectomy incontinence as it enhances residual urinary sphincteric function and allows continence recovery or improvement by dorsal compression of the bulbar urethra through a fixed transobturator mesh passage. The mode of action and the profile of the patients with best results are not totally understood. (2) Methods: Intraoperative urethral pressure measurements at different filling levels of the ATOMS device show increased urethral resistance and enhanced residual sphincteric activity. We evaluated whether the pattern of urethral pressure change secondary to serial progressive intraoperative filling of the cushion can predict postoperative results after ATOMS placement. (3) Results: The regression analysis showed a significant direct relationship between cushion volume and intraurethral pressure (p = 0.000). The median intraurethral pressure at atmospheric pressure was 51 ± 22.7 cm H2O, and at atmospheric pressure plus 4 mL was 80 ± 23.1 cm H2O). Cluster analyses defined a group of patients (n = 6) formed by patients with a distensible urethra and 100% continence after adjustment in contrast to another group (n = 3) with rigid urethras and 33% continence after adjustment. (4) Conclusions: As a part of its continence mechanism, the ATOMS device leads to continence by increasing intraurethral pressure owing to the stretching effect on the urethral wall caused by cushion filling that increases urethral resistance.

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Excess molar volumes of 1,3 propanediol + (C1-C5) alkan-1-ols: Application of cubic EOS

Journal of the Serbian Chemical Society ◽

10.2298/jsc110616194a ◽

2012 ◽

Vol 77 (3) ◽

pp. 363-370 ◽

Cited By ~ 3

Author(s):

Mohammad Almasi ◽

Ladan Khosravi

Keyword(s):

Atmospheric Pressure ◽

Full Range ◽

Excess Molar Volumes ◽

Carbon Chain ◽

Carbon Chain Length ◽

Structural Factors ◽

Pressure Measurements ◽

Molar Volumes ◽

Pure Compounds ◽

Vibrating Tube Densimeter

Densities of the binary mixtures consist of methanol, ethanol, 1- propanol, 1-butanol and 1-pentanol with 1,3 Propanediol were measured at temperatures (293.15, 298.15, 303.15 and 313.15) K and atmospheric pressure. Measurements have been made over the full range of compositions and for the pure compounds by using a vibrating tube densimeter. Excess molar volumes have been obtained from these experimental results and were fitted to a Redlich-Kister type expansion. The results were interpreted in terms of molecular interactions and structural factors of the alcohols. It was observed that an increase of the alcohol carbon chain length led to lower interactions on mixing. The Peng-Robinson-Stryjek-Vera (PRSV) equation of state has been used to correlate the binary excess molar volumes.

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Perivascular pressure measurements by wick-catheter technique in isolated dog lobes

Journal of Applied Physiology ◽

10.1152/jappl.1979.46.5.950 ◽

1979 ◽

Vol 46 (5) ◽

pp. 950-955 ◽

Cited By ~ 23

Author(s):

M. Goshy ◽

S. J. Lai-Fook ◽

R. E. Hyatt

Keyword(s):

Surface Pressure ◽

Atmospheric Pressure ◽

Interstitial Fluid ◽

Fluid Pressure ◽

Pressure Measurements ◽

Loose Connective Tissue ◽

Catheter Technique ◽

Pleural Surface ◽

Mechanics Analysis ◽

The Difference

Saline-filled wick catheters were inserted intraparenchymally in the loose connective tissue separating the bronchus and pulmonary artery of unperfused isolated dog lobes. Px, the difference between perivascular pressure and pleural surface pressure (which was atmospheric pressure), was measured by the wick for arterial pressures (Pa) of 10 and 25 cmH2O at lobe transpulmonary pressures (Ptp) of 25, 15, 10, 5, and 2 cmH2O during a deflation pressure-volume maneuver. The response time of Px to step changes in Pa was relatively short, a pressure plateau always occurring in less than 3 min. For Pa of 25 cmH2O, mean Px in five lobes was -2 cmH2O at Ptp of 2 cmH2O and decreased almost linearly to -9 cmH2O at Ptp of 25 cmH2O. Reducing Pa from 25 to 10 cmH2O resulted in a mean decrease in Px of 1 cmH2O at Ptp of 2 cmH2O and 2 cmH2O at Ptp of 25 cmH2O. These results are generally consistent with predictions from a continuum-mechanics analysis of pulmonary vascular interdependence and do not support the concept that perivascular interstitial fluid pressure is different from surface pressure.

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Spouted bed reactor for kinetic measurements of reduction of Fe2O3 in a CO2/CO atmosphere Part I: Atmospheric pressure measurements and equipment commissioning

Chemical Engineering Research and Design ◽

10.1016/j.cherd.2016.06.028 ◽

2016 ◽

Vol 114 ◽

pp. 307-320 ◽

Cited By ~ 14

Author(s):

Zili Zhang ◽

Thomas P. Hills ◽

Stuart A. Scott ◽

Paul S. Fennell

Keyword(s):

Atmospheric Pressure ◽

Pressure Measurements ◽

Spouted Bed ◽

Kinetic Measurements

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An experiment to determine the atmospheric pressure profile of a planet using base pressure measurements

10.2514/6.1972-202 ◽

1972 ◽

Keyword(s):

Atmospheric Pressure ◽

Pressure Profile ◽

Base Pressure ◽

Pressure Measurements

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The physical and thermodynamic properties of some associated solutions II. Heat capacities and compressibilities

Proceedings of the Royal Society of London Series A - Mathematical and Physical Sciences ◽

10.1098/rspa.1964.0083 ◽

1964 ◽

Vol 278 (1375) ◽

pp. 574-587 ◽

Cited By ~ 32

Keyword(s):

Heat Capacity ◽

Hydrogen Bonding ◽

Thermodynamic Properties ◽

Ultrasonic Velocity ◽

Atmospheric Pressure ◽

Dipolar Interaction ◽

Heat Capacities ◽

Pressure Measurements ◽

Associated Solutions ◽

Volume Dependence

The heat capacities of liquid piperidine, tetrahy dropyran, and cyclohexane, and of binary mixtures formed therefrom , have been determined in the temperaturerange 20 to 60 °C at atmospheric pressure. Measurements of ultrasonic velocity and density have enabled adiabatic and isothermal compressibilities to be evaluated. The heat capacities at constant volume have been resolved into four components in the cases of cyclohexane and tetrahydropyran, the structural contributions being approximately 1/2 R and R cal mole -1 deg -1 respectively. For cyclohexane, the volume dependence of the heat capacity has also been calculated. Differences between molecular association due to dipolar interaction and that due to hydrogen bonding, evidenced by the properties of pure tetrahydropyran and piperidine, are also apparent in the excess heat capacities, excess compressibilities, and excess volumes of the systems.

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Accuracy of the Phoenix and Viking atmospheric pressure measurements: impact on detecting the climate change on Mars

10.5194/epsc2021-63 ◽

2021 ◽

Author(s):

Henrik Kahanpää ◽

Jouni Polkko ◽

Michael Daly

Keyword(s):

Climate Change ◽

Pressure Measurement ◽

Atmospheric Pressure ◽

Barometric Pressure ◽

Pressure Measurements ◽

Pressure Data ◽

Phoenix Mission ◽

The Difference ◽

The Phoenix

Attempts have been made to detect secular changes in the Martian climate by comparing surface atmospheric pressure measurements separated by several decades [1][2]. Such multi-mission studies require information on the exact accuracies of the corresponding pressure measurements. In this presentation, we discuss results of our recently published study on the quality of the pressure data measured by the Mars Phoenix lander [3]. In addition, we evaluate the absolute accuracy of the Viking pressure data by using (less well known) sources in the literature [4][5]. Our results show that at the beginning of the Phoenix mission the offset of the pressure measurement was between -4.8 Pa and +0.1 Pa. The drift of the sensor during the mission was between -0.5 Pa and +3.4 Pa. Thus, the Phoenix pressure measurement was much more accurate than was reported immediately after the mission [6]. However, the systematic error of the Viking pressure data could be up to 8.8 Pa. Haberle and Kahre (2010) found the Phoenix surface pressures to be ~10 Pa higher than the Viking surface pressures after correcting for elevation differences and dynamics [1]. Although our results show the Phoenix measurement to be more accurate than assumed by Haberle and Kahre (2010), the difference they found could still be explained by the uncertainty of the Viking pressure data. On the other hand, our results show that the Phoenix pressure data can be used as an accurate comparison point for future surface pressure measurements on Mars. References: [1] Haberle and Kahre, "Detecting secular climate change on Mars ", Mars, 5, 68&#8211;75, 2010. [2] Batterson et al., "Secular Climate Change on Mars: An Update", AGU Fall Meeting, 2017. [3] Kahanp&#228;&#228; et al., "The quality of the Mars Phoenix pressure data", Planet. Space Sci., 181, 104814, 2020. [4] Seiff, "The Viking atmosphere structure experiment - Techniques, instruments, and expected accuracies", Space Sci. Instrum., 2, 381&#8211;423, 1976. [5] Mitchell, "Evaluation of Viking Lander barometric pressure sensor", NASA Technical Memorandum, NASA-TM-X-74020, 1977. [6] Taylor et al., "On pressure measurement and seasonal pressure variations during the Phoenix mission", J. Geophys. Res., 115, E00E15, 2010. Acknowledgments: The contribution of H. Kahanp&#228;&#228; in this study was supported by The Finnish Cultural Foundation [grant number 00170395]. The contribution of M. Daly was supported by the Canadian Space Agency. We wish to thank Germ&#225;n Mart&#237;nez (USRA/LPI) for providing a copy of reference article [4].

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