• Title/Summary/Keyword: Mean Pressure

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The Effects of Cortex Phellodendri on Prostatic Urethral Pressure and Mean Arterial Blood Pressure in an Experimental Rabbit Model (황백(黃柏)이 토끼의 전립선요도압 및 혈압에 미치는 영향)

  • Kim, Eun-ji;Han, Yang-hee
    • The Journal of Internal Korean Medicine
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    • v.38 no.2
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    • pp.110-117
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    • 2017
  • Objective: This study was undertaken to examine the effect of Cortex Phellodendri on prostatic urethral pressure and mean arterial blood pressure of rabbits. Methods: To measure prostatic urethral pressure and mean arterial blood pressure, a Mikro-Tip catheter transducer was inserted and positioned in the prostatic urethra and left carotid artery. After a stabilizing period, phenylephrine ($1{\mu}/kg$) was intravenously administered two or three times to increase the urethral pressure and mean arterial blood pressure. Cortex Phellodendri (2.5 mg/kg and 5 mg/kg doses of Cortex Phellodendri extracted from 80% Ethanol) was administered intravenously, followed by phenylephrine, with no time interval between the doses. The urethral pressure and mean arterial blood pressure were then measured to determine whether they had stabilized. Results and Conclusion: Cortex Phellodendri appeared to inhibit phenylephrine-induced increases in prostatic urethral pressure and mean arterial blood pressure.

Effects of quadriceps angle on patellofemoral contact pressure

  • Yoo, Yoon-Hyeong;Lee, Sung-Jun;Jeong, Soon-wuk
    • Journal of Veterinary Science
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    • v.21 no.5
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    • pp.69.1-69.11
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    • 2020
  • Background: An inappropriate Q angle may affect the biomechanics of the canine patellofemoral joint. Objectives: The purpose of this study was to evaluate the effects of changes in quadriceps angle (Q angle) on patellofemoral joint pressure distribution in dogs. Methods: Eight stifles were positioned at 45, 60, 75, 90, 105, and 120° of flexion in vitro, and 30% body weight was applied through the quadriceps. Patellofemoral contact pressure distribution was mapped and quantified using pressure-sensitive film. For the pressure area, mean pressure, peak pressure, medial peak pressure, and lateral peak pressure, differences between groups according to conditions for changing the Q angle were statistically compared. Results: Increases of 10° of the Q angle result in increases in the pressure area (P = 0.04), mean pressure (P = 0.003), peak pressure, and medial peak pressure (P ≤ 0.01). Increasing the Q angle by 20° increases the pressure area (P = 0.021), mean pressure (P ≤ 0.001), peak pressure (P ≤ 0.01), and medial peak pressure (P ≤ 0.01) significantly, and shows higher mean (P ≤ 0.001) and peak pressures than increasing by 10°. Decreasing the Q angle increases the mean pressure (P = 0.013), peak pressure, and lateral peak pressure (P ≤ 0.001). Conclusions: Both increases and decreases in the Q angle were associated with increased peak patellofemoral pressure, which could contribute to the overloading of the cartilage. Therefore, the abnormal Q angle should be corrected to the physiologically normal value during patellar luxation repair and overcorrection should be avoided.

Analysis of Plantar Foot Pressure in Skilled and Unskilled Player's during a Free Throw in Basketball (농구 자유투 동작 시 숙련자 및 미숙련자의 족저압력 분석)

  • Kim, Chang-Hyun;Lee, Joong-Sook;Jang, Young-Min
    • Korean Journal of Applied Biomechanics
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    • v.22 no.2
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    • pp.183-191
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    • 2012
  • The objective of this study was to evaluate the plantar foot pressure of skilled and unskilled players during a free throw. The experiment performed here in measured the movement route of the mean foot pressure, maximum foot pressure, and center of pressure in four event zones (ready, maximum knee flexion, release event, and maximum knee extension) for both groups while they were wearing the plantar foot pressure measurement equipment under identical conditions. The major findings are as follows. When getting ready (RD) during a free throw, the skilled player group had higher mean and maximum foot pressures, although neither variable showed significant differences statistically. For the maximum knee flexion (MF) during a free throw, the skilled player group had higher mean and maximum foot pressures, but only the mean foot pressure significantly differed statistically. For the release event (RE) during a free throw, the unskilled player group had higher mean and maximum foot pressures, but only the mean foot pressure significantly differed statistically. During the maximum knee extension (ME) of a free throw, the unskilled player group had a higher mean foot pressure, and the skilled player group had a higher maximum foot pressure. No significant correlation was found between the two groups. For the skilled player group, movement towards the center of pressure showed a stable form that moved from the rear to the front and from side to side during a free throw. For the unskilled player group, movement towards the center of pressure was unstable, which made it impossible to move from the rear to the front and from left to right.

Evluation of the DINAMAP 8100 Automated Blood Pressure monitor ; comparison with the Mercury Sphygmomanometer (수은 혈압계와 DINAMAP 8100 자동 혈압계의 혈압측정치 비교연구)

  • Kim Mee-Yeon;Choi Hee-Kang;Kim Nam-Jin
    • Journal of Korean Academy of Fundamentals of Nursing
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    • v.3 no.1
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    • pp.96-107
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    • 1996
  • Automated blood pressure monitors have gained acceptance in many clinical settings with the increasing demand, the accurate BP measuring devices reguire the need for validation. We have evaluated the Dinamap 8100, an oscillometric automated blood pressure monitor, using the Mercury sphygmomanometer as a reference. Comparison of sphygmomanometers was conducted 60 patients (30-Normotensive group, 30-Hypertensive group at Seoul National University Hospital. Two trained observers took measure blood pressure(systolic/diastolic) at the same time using the Dinamap 8100 on one arm and the Mercury on the other. For each measurement, the device was randomly selected from a group of devices repetively used for the experiment. Mean readings for systolic pressure with the Dinamap 8100 in normotensive group were lower(mean difference ; 4.26mmHg) than the Mercury type. Mean readings for systolic pressure with the Dinamap 8100 in hypertensive group were lower(mean difference ; 9.05mmHg) than the Mercury type. Mean readings for diastolic pressure with the Dinamap 8100 in normotensive group were lower (mean difference ; 7.46mmHg) than the Mercury type. Mean readings for diastolic pressure with the Dinamap 8100 in hypertensive group were lower(mean difference ; 9.03mmHg) than the Mercury type. We have found that blood pressure readings with the Dinamap 8100 were lower than those with the Mercury type. we are using the Mercury type in clinics, although it has observer bias and terminal digit preference. But the Dinamap 8100 is readily portable, simple to use, and capable of preventing observer bias and terminal digit preference. The Dinamap 8100 is acceptable for blood pressure determination in subjects who are normotensive or hypertensive ones.

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Analysis of Plantar Pressure Differences between Flat Insole Trekking Shoes and Nestfit Trekking Shoes (네스핏 트레킹화와 평면 인솔 트레킹화의 족저압력 분석)

  • Choi, Jae-Won;Lee, Joong-Sook
    • Korean Journal of Applied Biomechanics
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    • v.25 no.4
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    • pp.475-482
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    • 2015
  • Objective : The purpose of this study was to investigate mean plantar foot pressure, maximum plantar pressure and ground reaction force, and center migration path of pressure according to the type of trekking shoes for the development of shoes. Method : Subjects of the study averaged $22.10{\pm}2.05years$ of age. Their average height was $169.27{\pm}7.62cm$ and their average weight was $64.34{\pm}10.22kg$. The method of this study was administered measuring 50 steps, at once, 3 times at a speed of 4 km/h and using the data of 30 steps. Pedar-X system measured the mean foot pressure, maximum foot pressure, mean maximum force, and center migration path of pressure by subjects' position while walking. Statistical analysis was performed by SPSS 23.0 using a paired t-test. Results : Results of the study showed Nestfit trekking shoes lower foot pressure of both feet in mean foot pressure and maximum foot pressure. Nestfit trekking shoes showed high ground reaction force (p<.001) in the midfoot, and low mean ground reaction force in the rearfoot. The center migration path of pressure showed the Nestfit trekking shoes were more stable than flat insole trekking shoes. Conclusion : It can be concluded that wearing Nestfit trekking shoes spreads pressure efficiently and induces walking stability because Nestfit trekking shoes spread the pressure of the forefoot and rearfoot to the midfoot and the center migration path of pressure shows regularly.

Hemodynamic effects of induced overtransfusion of blood in dogs (과량수혈이 혈역학에 미치는 영향)

  • 기노석
    • Journal of Chest Surgery
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    • v.17 no.3
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    • pp.418-423
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    • 1984
  • Appreciation of the large volume deficits which may occur in surgical or trauma patients due to blood loss has led to vigorous transfusion techniques designed to overt hypovolemic shock and ischemic damage to vital organs which may develop in minutes during the hypovolemic state. In a significant proportion of patients treated with massive rapid blood or fluid transfusion, hypervolemia occurs and life threatening pulmonary edema may develop. Especially, hypervolemia may occur during transfusion for preventing development of the so-called low output syndrome following cardiac surgery. However, the most effective indicator which reveals the adequate level of transfusion is not settled yet. The present study was aimed to compare the effectiveness of the indicators suggested thus far and to determine the most sensitive one. Eight dogs were experimentally studied in terms of left atrial pressure, pulmonary arterial systolic pressure, central venous pressure, mean systemic arterial pressure and heart rate before and after induced hypervolemia with infusion of 600ml heparinized homologous blood. Immediately after induced overtransfusion of the blood, pulmonary arterial systolic pressure increased 75.0%, in omparison with the control before transfusion, left atrial pressure 58.8%, central venous pressure 44.6%, and mean systemic arterial pressure 10.1%, one hour after transfusion, pulmonary arterial systolic pressure 40.0%, left atrial pressure 21.2%, central venous pressure 14.5%, and mean systemic arterial pressure 3.2%, central venous pressure 14.5%, and mean systemic arterial pressure 3.2%, respectively. Heart rate showed no significant change throughout the experiment. These result suggested that the changes of the pulmonary arterial systolic pressure is the most sensitive indicator for detection of hypervolemia during blood transfusion.

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The Effects of Essential Oils from Softwood on Pain and Cardiovascular System (침엽수종 유래 정유가 진통 및 순환기계에 미치는 영향)

  • 나기정;정의배
    • Journal of Veterinary Clinics
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    • v.16 no.2
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    • pp.253-256
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    • 1999
  • The influence of essential oils from aboriginal softwoods as Pinus densiflora, Pinus koraiensis, Chamaecyparis obtusa and Chamaecyparis pisifera on the motor coordination, pulse, mean blood artery pressure and pain reducing test was investigated in mice and rats. The motor coordination of mouse was not induced by the inhalation of each oil. Furthermore, these oils did not alter the changes of the mean blood pressure and pulse rate. Chamaecyparis pisifera trand to reduce the mean blood pressure. The abdominal pain induced by acetic acid was reduced only by an essential oil from Pinus koraiensis in mouse.

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Effects of cyclic mean pressure of helium gas on performance of integral crank driven stirling cryocooler

  • Hong, Yong-Ju;Ko, Junseok;Kim, Hyo-Bong;Park, Seong-Je
    • Progress in Superconductivity and Cryogenics
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    • v.18 no.3
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    • pp.30-34
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    • 2016
  • An integral crank driven Stirling cryocooler is solidly based on concepts of direct IR detector mounting on the cryocooler's cold finger, and the integral construction of the cryocooler and Dewar envelope. Performance factors of the cryocooler depend on operating conditions of the cryocooler such as a cyclic mean pressure of the working fluid, a rotational speed of driving mechanism, a thermal environment, a targeted operation temperature and etc.. At given charging condition of helium gas, the cyclic mean pressure of helium gas in the cryocooler changes with temperatures of the cold end and the environment. In this study, effects of the cyclic mean pressure of helium gas on performances of the Stirling cryocooler were investigated by numerical analyses using the Sage software. The simulation model takes into account thermodynamic losses due to an inefficiency of regenerator, a pressure drop, a shuttle heat transfer and solid conductions. Simulations are performed for the performance variation according to the cyclic mean pressure induced by the temperature of the cold end and the environment. This paper presents P-V works in the compression and expansion space, cooling capacity, contribution of losses in the expansion space.

Effect of Injection Pressure on Atomization Characteristics of Fuel Spray in High-Pressure Gasoline Injector (가솔린 인젝터의 연료 분무 미립화 특성에 미치는 분사 압력의 영향)

  • Lee, Chang-Sik;Choi, Soo-Chon;Kim, Min-Kyu;Kwon, Sang-Il
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.24 no.4
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    • pp.555-560
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    • 2000
  • This paper describes the macroscopic behavior and atomization characteristics of the high-pressure gasoline injector in direct-injection gasoline engine. The global spray behavior of fuel injector was visualized by shadowgraph technique. The atomization characteristics of gasoline spray such as mean diameter and mean velocity of droplet were measured by the phase Doppler particle analyzer system. In order to obtain the influence of fuel injection pressure, the macroscopic visualization and experiment of particle measurement on the fuel spray were investigated at 3,5 and 7 MPa of injection pressure under different surrounding pressure in the spray chamber. The results of this work show that the fuel injection pressure of gasoline injector in GDl engine has influence upon the mean droplet diameter, mean velocity of spray droplet, the spray tip penetration, and spray width under the elevated ambient pressure.

A Study on the Droplet Size Distribution of Ultra High Pressure Diesel Spray on Electronic Hydraulic Fuel Injection System (전자유압식 분사계에 의한 초고압 디젤분무의 입경분포에 관한 연구)

  • Jang, S.H.;Ahn, S.K.
    • Journal of Power System Engineering
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    • v.2 no.1
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    • pp.25-30
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    • 1998
  • In order to investigate the droplet size distribution and Sauter Mean Diameter in a ultra high pressure diesel spray, fuel was injected with ultra high pressure into the environments of high pressure and room temperature by an Electronic Hydraulic Fuel Injection System. Droplet size was measured with the immersion liquid sampling technique. The immersion liquid was used a mixture of water-methycellulose solution and ethanol. The Sauter Mean Diameter decreased with increasing injection pressure, with a decrease environmental pressure (back pressure) and nozzle diameter. Increasing the injection pressure makes the fuel density distribution of the spray more homogeneous. An empirical correlation was developed among injection pressure, air density, nozzle diameter and the Sauter Mean Diameter of spray droplets.

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