Search results for: Increased intrauterine pressure
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 11707

Search results for: Increased intrauterine pressure

11707 Transgenerational Impact of Intrauterine Hyperglycaemia to F2 Offspring without Pre-Diabetic Exposure on F1 Male Offspring

Authors: Jun Ren, Zhen-Hua Ming, He-Feng Huang, Jian-Zhong Sheng

Abstract:

Adverse intrauterine stimulus during critical or sensitive periods in early life, may lead to health risk not only in later life span, but also further generations. Intrauterine hyperglycaemia, as a major feature of gestational diabetes mellitus (GDM), is a typical adverse environment for both F1 fetus and F1 gamete cells development. However, there is scare information of phenotypic difference of metabolic memory between somatic cells and germ cells exposed by intrauterine hyperglycaemia. The direct transmission effect of intrauterine hyperglycaemia per se has not been assessed either. In this study, we built a GDM mice model and selected male GDM offspring without pre-diabetic phenotype as our founders, to exclude postnatal diabetic influence on gametes, thereby investigate the direct transmission effect of intrauterine hyperglycaemia exposure on F2 offspring, and we further compared the metabolic difference of affected F1-GDM male offspring and F2 offspring. A GDM mouse model of intrauterine hyperglycemia was established by intraperitoneal injection of streptozotocin after pregnancy. Pups of GDM mother were fostered by normal control mothers. All the mice were fed with standard food. Male GDM offspring without metabolic dysfunction phenotype were crossed with normal female mice to obtain F2 offspring. Body weight, glucose tolerance test, insulin tolerance test and homeostasis model of insulin resistance (HOMA-IR) index were measured in both generations at 8 week of age. Some of F1-GDM male mice showed impaired glucose tolerance (p < 0.001), none of F1-GDM male mice showed impaired insulin sensitivity. Body weight of F1-GDM mice showed no significance with control mice. Some of F2-GDM offspring exhibited impaired glucose tolerance (p < 0.001), all the F2-GDM offspring exhibited higher HOMA-IR index (p < 0.01 of normal glucose tolerance individuals vs. control, p < 0.05 of glucose intolerance individuals vs. control). All the F2-GDM offspring exhibited higher ITT curve than control (p < 0.001 of normal glucose tolerance individuals, p < 0.05 of glucose intolerance individuals, vs. control). F2-GDM offspring had higher body weight than control mice (p < 0.001 of normal glucose tolerance individuals, p < 0.001 of glucose intolerance individuals, vs. control). While glucose intolerance is the only phenotype that F1-GDM male mice may exhibit, F2 male generation of healthy F1-GDM father showed insulin resistance, increased body weight and/or impaired glucose tolerance. These findings imply that intrauterine hyperglycaemia exposure affects germ cells and somatic cells differently, thus F1 and F2 offspring demonstrated distinct metabolic dysfunction phenotypes. And intrauterine hyperglycaemia exposure per se has a strong influence on F2 generation, independent of postnatal metabolic dysfunction exposure.

Keywords: inheritance, insulin resistance, intrauterine hyperglycaemia, offspring

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11706 Thrombophilic Risk Factors and Pregnancy Complications

Authors: Hanan Azzam1, Nashwa Abousamra1, Amany Mansour1, Yaser Abd El-dayem2, , Solafa Elsharawy1

Abstract:

Background: Inherited thrombophilias are a heterogenous group of conditions which have been implicated in a variety of pregnancy complications. More recently, deficiency of protein Z (PZ) has been liked to pregnancy complications, including preterm delivery. Aim: We designed this study to evaluate the association of inherited thrombophilias including [Protein C (PC), Protein S (PS), Anti thrombin III (ATIII) deficiency and activated protein C (APC) resistance] and protein Z deficiency with a variety of pregnancy complications. Patients and Methods: 60 women with different pregnancy complications, including 20 patients with preeclampsia, 20 patients with intrauterine growth resistance (IUGR), and 20 patients with intrauterine fetal death (IUFD), in addition to 30 healthy pregnant women were recruited for the present study. PC and free PS antigen, ATIII activity, modified functional APC-resistance, and PZ levels were determined. Results: There was no significant association between inherited thrombophilias and complicated pregnancies as regards PC deficiency (p=1.0), AT III and PS deficiency (p=0.312), and APC-resistance (P=0.083). PZ was significantly associated with complicated pregnancies (p=0.012). Patients with protein Z levels below 1.5 µg/ml were considered deficient. Accordingly, we demonstrated protein Z deficiency in 30% of complicated pregnancies (RR 6.0, 95% CI 1.29-27.90;p=0.022), 20% of preeclampsia (RR 3.5, 95% CI 0.57 – 21.28; P = 0.174), 40% of IUGR (RR 9.3 95% CI 1.72-50.61; P = 0.010) and 30% of IUFD (RR 6, 95% CI 1.07 – 33.64; P = 0.042). Conclusions: These findings indicate the absence of association of inherited thrombophilias, including PC, PS, AT III deficiency, and APC resistance with pregnancy complications. However, PZ deficiency is associated with increased risk of pregnancy complications, especially intrauterine growth restriction and intrauterine fetal death.

Keywords: protein C, protein S, thrombophelia, pregnancy, protein Z

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11705 A Study of the Growth of Single-Phase Mg0.5Zn0.5O Films for UV LED

Authors: Hong Seung Kim, Chang Hoi Kim, Lili Yue

Abstract:

Single-phase, high band gap energy Zn0.5Mg0.5O films were grown under oxygen pressure, using pulse laser deposition with a Zn0.5Mg0.5O target. Structural characterization studies revealed that the crystal structures of the ZnX-1MgXO films could be controlled via changes in the oxygen pressure. TEM analysis showed that the thickness of the deposited Zn1-xMgxO thin films was 50–75 nm. As the oxygen pressure increased, we found that one axis of the crystals did not show a very significant increase in the crystallization compared with that observed at low oxygen pressure. The X-ray diffraction peak intensity for the hexagonal-ZnMgO (002) plane increased relative to that for the cubic-ZnMgO (111) plane. The corresponding c-axis of the h-ZnMgO lattice constant increased from 5.141 to 5.148 Å, and the a-axis of the c-ZnMgO lattice constant decreased from 4.255 to 4.250 Å. EDX analysis showed that the Mg content in the mixed-phase ZnMgO films decreased significantly, from 54.25 to 46.96 at.%. As the oxygen pressure was increased from 100 to 150 mTorr, the absorption edge red-shifted from 3.96 to 3.81 eV; however, a film grown at the highest oxygen pressure tested here (200 mTorr).

Keywords: MgO, UV LED, ZnMgO, ZnO

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11704 Changes in Kidney Tissue at Postmortem Magnetic Resonance Imaging Depending on the Time of Fetal Death

Authors: Uliana N. Tumanova, Viacheslav M. Lyapin, Vladimir G. Bychenko, Alexandr I. Shchegolev, Gennady T. Sukhikh

Abstract:

All cases of stillbirth undoubtedly subject to postmortem examination, since it is necessary to find out the cause of the stillbirths, as well as a forecast of future pregnancies and their outcomes. Determination of the time of death is an important issue which is addressed during the examination of the body of a stillborn. It is mean the period from the time of death until the birth of the fetus. The time for fetal deaths determination is based on the assessment of the severity of the processes of maceration. To study the possibilities of postmortem magnetic resonance imaging (MRI) for determining the time of intrauterine fetal death based on the evaluation of maceration in the kidney. We have conducted MRI morphological comparisons of 7 dead fetuses (18-21 gestational weeks) and 26 stillbirths (22-39 gestational weeks), and 15 bodies of died newborns at the age of 2 hours – 36 days. Postmortem MRI 3T was performed before the autopsy. The signal intensity of the kidney tissue (SIK), pleural fluid (SIF), external air (SIA) was determined on T1-WI and T2-WI. Macroscopic and histological signs of maceration severity and time of death were evaluated in the autopsy. Based on the results of the morphological study, the degree of maceration varied from 0 to 4. In 13 cases, the time of intrauterine death was up to 6 hours, in 2 cases - 6-12 hours, in 4 -12-24 hours, in 9 -2-3 days, in 3 -1 week, in 2 -1,5-2 weeks. At 15 dead newborns, signs of maceration were absent, naturally. Based on the data from SIK, SIF, SIA on MR-tomograms, we calculated the coefficient of MR-maceration (M). The calculation of the time of intrauterine death (MP-t) (hours) was performed by our formula: МR-t = 16,87+95,38×М²-75,32×М. A direct positive correlation of MR-t and autopsy data from the dead at the gestational ages 22-40 weeks, with a dead time, not more than 1 week, was received. The maceration at the antenatal fetal death is characterized by changes in T1-WI and T2-WI signals at postmortem MRI. The calculation of MP-t allows defining accurately the time of intrauterine death within one week at the stillbirths who died on 22-40 gestational weeks. Thus, our study convincingly demonstrates that radiological methods can be used for postmortem study of the bodies, in particular, the bodies of stillborn to determine the time of intrauterine death. Postmortem MRI allows for an objective and sufficiently accurate analysis of pathological processes with the possibility of their documentation, storage, and analysis after the burial of the body.

Keywords: intrauterine death, maceration, postmortem MRI, stillborn

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11703 Metal Berthelot Tubes with Windows for Observing Cavitation under Static Negative Pressure

Authors: K. Hiro, Y. Imai, T. Sasayama

Abstract:

Cavitation under static negative pressure is not revealed well. The Berthelot method to generate such negative pressure can be a means to study cavitation inception. In this study, metal Berthelot tubes built in observation windows are newly developed and are checked whether high static negative pressure is generated or not. Negative pressure in the tube with a pair of a corundum plate and an aluminum gasket increased with temperature cycles. The trend was similar to that as reported before.

Keywords: Berthelot method, cavitation, negative pressure, observation

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11702 Rrelationship Between Intrauterine Growth Retardation and TORCH Infections in Neonates

Authors: Seyed Saeid Nabavi

Abstract:

Background: Many infants with intrauterine growth disorder are screened for TORCH infections. This action has no economic justification in terms of the imposed costs. In this regard, due to the research gap in this field, this study aimed to investigate the relationship between intrauterine growth disorder and TORCH infection in neonates referred to Milad hospital in 2019 and 2020. Materials and Methods: In this cross-sectional study, 41IUGR newborns were selected and evaluated based on diagnostic and clinical studies in Milad Hospital in 2019 and 2020. TORCH results found in IgG and IgM antibody titer assay were tested in mother and infant. Antibody titers of toxoplasmosis, rubella, cytomegalovirus, herpes, and syphilis were determined in cases, and other variables were compared. The collected data were entered in SPSS software 25 and analyzed at a significant level of 0.05 using the statistical tests of Kolmogorov–Smirnov, Shapiro–Wilk, chi-square, and Mann–Whitney. Results: Most of the IUGR infants studied were girls (68.3%), Gravida and Parity were reported to be 68.3% and 80%, respectively, in the study. Mean weight, APGAR score, and neonatal gestational age are reported as 1710.62±334.43 g, 7.71±1.47, and 35.7+ 1.98 weeks, respectively. Most of the newborns were born by cesarean section (92.7%). TORCH infection was reported in three patients, 7.3%. The mean gestational age of IUGR infants with TORCH infection was reported to be less than other babies with IUGR. Therefore, the mean gestational age of subjects with TORCH infection was 33±1.4 weeks and in others 35.94±1.91 weeks (p-value = 0.038). No significant relationship between TORCH infection and gender, gravidity, and parity of newborns was found (p-value > 0.05). Conclusion: TORCH infection was reported in 3 patients( 7.3%). No significant relationship between TORCH infection and gender, gravidity, and parity of newborns was found. p-value > 0.05

Keywords: congenital infection, intrauterine growth restriction, TORCH infections, neonates

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11701 Use of High Hydrostatic Pressure as an Alternative Preservation Method in Camels Milk

Authors: Fahad Aljasass, Hamza Abu-Tarboush, Salah Aleid, Siddig Hamad

Abstract:

The effects of different high hydrostatic pressure treatments on the shelf life of camel’s milk were studied. Treatments at 300 to 350 MPa for 5 minutes at 40°C reduced microbial contamination to levels that prolonged the shelf life of refrigerated (3° C) milk up to 28 days. The treatment resulted in a decrease in the proteolytic activity of the milk. The content of proteolytic enzymes in the untreated milk sample was 4.23 µM/ml. This content decreased significantly to 3.61 µM/ml when the sample was treated at 250 MPa. Treatment at 300 MPa decreased the content to 3.90 which was not significantly different from the content of the untreated sample. The content of the sample treated at 350 MPa dropped to 2.98 µM/ml which was significantly lower than the contents of all other treated and untreated samples. High pressure treatment caused a slight but statistically significant increase in the pH of camel’s milk. The pH of the untreated sample was 6.63, which increased significantly to 6.70, in the samples treated at 250 and 350 MPa, but insignificantly in the sample treated at 300 MPa. High pressure treatment resulted in some degree of milk fat oxidation. The thiobarbituric acid (TBA) value of the untreated sample was 0.86 mg malonaldehyde/kg milk. This value remained unchanged in the sample treated at 250 MPa, but then it increased significantly to 1.25 and 1.33 mg/kg in the samples treated at 300 and 350 MPa, respectively. High pressure treatment caused a small increase in the greenness (a* value) of camel’s milk. The value of a* was reduced from -1.17 for the untreated sample to -1.26, -1.21 and -1.30 for the samples treated at 250, 300 and 350 MPa, respectively. Δa* at the 250 MPa treatment was -0.09, which then decreased to -0.04 at the 300 MPa treatment to increase again to -0.13 at the 350 MPa treatment. The yellowness (b* value) of camel’s milk increased significantly as a result of high pressure treatment. The b* value of the untreated sample was 1.40, this value increased to 2.73, 2.31 and 2.18 after treatments at 250, 300 and 350 MPa, respectively. The Δb* value was +1.33 at the treatment 250 MPa, decreased to +0.91 at 300 MPa and further to +0.78 at 350 MPa. The pressure treatment caused slight effect on color, slight decrease in protease activity and a slight increase in the oxidation products of lipids.

Keywords: high hydrostatic pressure, camel’s milk, mesophilic aerobic bacteria, clotting, protease

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11700 Pressure Regulator Optimization in LPG Fuel Injection Systems

Authors: M. Akif Ceviz, Alirıza Kaleli, Erdoğan Güner

Abstract:

LPG pressure regulator is a device which is used to change the phase of LPG from liquid to gas by decreasing the pressure. During the phase change, it is necessary to supply the latent heat of LPG to prevent excessive low temperature. Engine coolant is circulated in the pressure regulator for this purpose. Therefore, pressure regulator is a type of heat exchanger that should be designed for different engine operating conditions. The design of the regulator should ensure that the flow of LPG is in gaseous phase to the injectors during the engine steady state and transient operating conditions. The pressure regulators in the LPG gaseous injection systems currently used can easily change the phase of LPG, however, there is no any control on the LPG temperature in conventional LPG injection systems. It is possible to increase temperature excessively. In this study, a control unit has been tested to keep the LPG temperature in a band. Result of the study showed that the engine performance characteristics can be increased by using the system.

Keywords: temperature, pressure regulator, LPG, PID

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11699 A Case Study of Spontaneous Heterotopic Pregnancy with Subsequent Ruptured Ectopic Pregnancy

Authors: M. Elder, L. Beech, A. Mackie

Abstract:

Heterotopic pregnancy is an uncommon and potentially life-threatening condition in which there is simultaneous occurrence of intrauterine and ectopic pregnancies. It has an incidence of approximately 1:3900 pregnancies, occurring in only 1:30000 spontaneous pregnancies. This study presents a rare case of spontaneous heterotopic pregnancy in a 34-year-old primiparous woman who was brought in by ambulance to the emergency department following collapse at 20+1 weeks gestation after normal first trimester screening and morphology scan. She was hemodynamically unstable and fetal heart rate was 60bpm. Initial resuscitation included transfusion of 2 units packed red blood cells and 1g intravenous tranexamic acid. Bedside ultrasound revealed evidence of approximately 1000ml clot in the right upper quadrant. She underwent a diagnostic laparoscopy and washout, which proceeded to a midline exploratory laparotomy. This revealed a 2.6L hemoperitoneum and query right ectopic pregnancy with calcified areas and clot, with no other cause of bleeding identified. Right salpingectomy was performed, and pathology later confirmed ectopic pregnancy. The intrauterine pregnancy had no complications, and she delivered a healthy full-term baby. This case demonstrates that ultrasound confirmation of intrauterine pregnancy does not exclude coexisting ectopic pregnancy. Heterotopic pregnancy should be considered in any pregnant woman presenting with abdominal pain or signs of hemorrhagic shock, as prompt diagnosis and treatment is essential to minimize foetal and maternal morbidity and mortality.

Keywords: ectopic pregnancy, hemorrhagic shock, salpingectomy, spontaneous heterotopic pregnancy

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11698 Induction of Labor Using Misoprostol with or without Mifepristone in Intrauterine Death: A Randomized Controlled Study

Authors: Ajay Agrawal, Pritha Basnet, Achala Thakur, Pappu Rizal, Rubina Rai

Abstract:

Context: Rapid expulsion of fetus in intrauterine fetal death (IUFD) is usually requested without any medical grounds for it. So; an efficient, safe method for induction of labor (IOL) is required. Objective: To determine if pre-treatment with mifepristone followed by IOL with misoprostol in late IUFD is more efficacious. Methods: We conducted a randomized controlled trial in 100 patients. Group-A women received single oral dose of 200 mg mifepristone, followed by induction with vaginal misoprostol after 24-hour. Group-B women were induced only with vaginal misoprostol. In each group 5 dose of misoprostol was used 4 hourly. If first cycle was unsuccessful, after break of 12 hour, second course of misoprostol was started. The primary outcome was a measure of induction to delivery time and vaginal delivery within 24 hours. Secondary outcome was to measure need of oxytocin and complications. Results: Maternal age, parity and period of gestation were comparable between groups. Number of misoprostol dose needed in group A was significantly less than group B. Mann Whitney U test showed, women in group A had significantly earlier onset of labor, however total induction to delivery interval was not significant. In group-A, 85.7% delivered within 24 hours of first dose of misoprostol while in group-B 70% delivered within 24 hour (p=0.07). More women in Group B required oxytocin. Conclusion: Pretreatment with mifepristone before IOL following late IUFD is an effective and safe regimen. It appears to shorten the duration of induction to onset of labor.

Keywords: induction of labor, intrauterine fetal death, mifepristone, misoprostol

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11697 Effect of Pressing Pressure on Mechanical Properties of Elaeis guineensis Jacq. Fronds-Based Composite Board

Authors: Ellisha Iling, Dayang Siti Hazimmah Ali

Abstract:

Experimental composite boards were fabricated using oil palm (Elaeis guineensis Jacq) fronds particles by applying hot press pressure of 5MPa, 6MPa and 7MPa respectively. Modulus of rupture (MOR) and internal bond strength (IB) of the composite boards made with target density of 0.80 g/cm³ were evaluated. Composite board fabricated under hot press pressure of 5MPa had MOR and IB values of 16.27 and 4.34 N/mm² respectively. Corresponding values for composite board fabricated under hot press pressure of 6MPa were 16.76 and 5.41 N/mm² respectively. Whereas, the MOR and IB values of composite board fabricated under hot press pressure of 7MPa were 17.24 and 6.19 N/mm² respectively. All composite boards met the MOR and IB requirement stated in Japanese Industrial Standard (JIS). Based on results of this work, the strength of mechanical properties of composite board increased with increase of hot press pressure. This study revealed that the selection of applied pressure during fabrication of composite board is important to improve mechanical properties of composite boards.

Keywords: composite board, Elaeis guineensis Jacq. Fronds, hot press pressure, mechanical properties

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11696 Estimation of Pressure Profile and Boundary Layer Characteristics over NACA 4412 Airfoil

Authors: Anwar Ul Haque, Waqar Asrar, Erwin Sulaeman, Jaffar S. M. Ali

Abstract:

Pressure distribution data of the standard airfoils is usually used for the calibration purposes in subsonic wind tunnels. Results of such experiments are quite old and obtained by using the model in the spanwise direction. In this manuscript, pressure distribution over NACA 4412 airfoil model was presented by placing the 3D model in the lateral direction. The model is made of metal with pressure ports distributed longitudinally as well as in the lateral direction. The pressure model was attached to the floor of the tunnel with the help of the base plate to give the specified angle of attack to the model. Before the start of the experiments, the pressure tubes of the respective ports of the 128 ports pressure scanner are checked for leakage, and the losses due to the length of the pipes were also incorporated in the results for the specified pressure range. Growth rate maps of the boundary layer thickness were also plotted. It was found that with the increase in the velocity, the dynamic pressure distribution was also increased for the alpha seep. Plots of pressure distribution so obtained were overlapped with those obtained by using XFLR software, a low fidelity tool. It was found that at moderate and high angles of attack, the distribution of the pressure coefficients obtained from the experiments is high when compared with the XFLR ® results obtained along with the span of the wing. This under-prediction by XFLR ® is more obvious on the windward than on the leeward side.

Keywords: subsonic flow, boundary layer, wind tunnel, pressure testing

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11695 Supersonic Combustion (Scramjet) Containing Flame-Holder with Slot Injection

Authors: Anupriya, Bikramjit Sinfh, Radhay Shyam

Abstract:

In order to improve mixing phenomena and combustion processes in supersonic flow, the current work has concentrated on identifying the ideal cavity parameters using CFD ANSYS Fluent. Offset ratios (OR) and aft ramp angles () have been manipulated in simulations of several models, but the length-to-depth ratio has remained the same. The length-to-depth ratio of all cavity flows is less than 10, making them all open. Hydrogen fuel was injected into a supersonic air flow with a Mach number of 3.75 using a chamber with a 1 mm diameter and a transverse slot nozzle. The free stream had conditions of a pressure of 1.2 MPa, a temperature of 299K, and a Reynolds number of 2.07x107. This method has the ability to retain a flame since the cavity facilitates rapid mixing of fuel and oxidizer and decreases total pressure losses. The impact of the cavity on combustion efficiency and total pressure loss is discussed, and the results are compared to those of a model without a cavity. Both the mixing qualities and the combustion processes were enhanced in the model with the cavity. The overall pressure loss as well as the effectiveness of the combustion process both increase with the increase in the ramp angle to the rear. When OR is increased, however, resistance to the supersonic flow field is reduced, which has a detrimental effect on both parameters. For a given ramp height, larger pressure losses were observed at steeper ramp angles due to increased eddy-viscous turbulent flow and increased wall drag.

Keywords: total pressure loss, flame holder, supersonic combustion, combustion efficiency, cavity, nozzle

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11694 Computational Fluid Dynamic Investigation into the Relationship between Pressure and Velocity Distributions within a Microfluidic Feedback Oscillator

Authors: Zara L. Sheady

Abstract:

Fluidic oscillators are being utilised in an increasing number of applications in a wide variety of areas; these include on-board vehicle cleaning systems, flow separation control on aircraft and in fluidic circuitry. With this increased use, there is a further understanding required for the mechanics of the fluidics of the fluidic oscillator and why they work in the manner that they do. ANSYS CFX has been utilized to visualise the pressure and velocity within a microfluidic feedback oscillator. The images demonstrate how the pressure vortices build within the oscillator at the points where the velocity is diverted from linear motion through the oscillator. With an enhanced understanding of the pressure and velocity distributions within a fluidic oscillator, it will enable users of microfluidics to more greatly tailor fluidic nozzles to their specification.

Keywords: ANSYS CFX, control, fluidic oscillators, mechanics, pressure, relationship, velocity

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11693 Valuation on MEMS Pressure Sensors and Device Applications

Authors: Nurul Amziah Md Yunus, Izhal Abdul Halin, Nasri Sulaiman, Noor Faezah Ismail, Ong Kai Sheng

Abstract:

The MEMS pressure sensor has been introduced and presented in this paper. The types of pressure sensor and its theory of operation are also included. The latest MEMS technology, the fabrication processes of pressure sensor are explored and discussed. Besides, various device applications of pressure sensor such as tire pressure monitoring system, diesel particulate filter and others are explained. Due to further miniaturization of the device nowadays, the pressure sensor with nanotechnology (NEMS) is also reviewed. The NEMS pressure sensor is expected to have better performance as well as lower in its cost. It has gained an excellent popularity in many applications.

Keywords: pressure sensor, diaphragm, MEMS, automotive application, biomedical application, NEMS

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11692 Numerical Investigation and Optimization of the Effect of Number of Blade and Blade Type on the Suction Pressure and Outlet Mass Flow Rate of a Centrifugal Fan

Authors: Ogan Karabas, Suleyman Yigit

Abstract:

Number of blade and blade type of centrifugal fans are the most decisive factor on the field of application, noise level, suction pressure and outlet mass flow rate. Nowadays, in order to determine these effects on centrifugal fans, numerical studies are carried out in addition to experimental studies. In this study, it is aimed to numerically investigate the changes of suction pressure and outlet mass flow rate values of a centrifugal fan according to the number of blade and blade type. Centrifugal fans of the same size with forward, backward and straight blade type were analyzed by using a simulation program and compared with each other. This analysis was carried out under steady state condition by selecting k-Ɛ turbulence model and air is assumed incompressible. Then, 16, 32 and 48 blade centrifugal fans were again analyzed by using same simulation program, and the optimum number of blades was determined for the suction pressure and the outlet mass flow rate. According to the results of the analysis, it was obtained that the suction pressure in the 32 blade fan was twice the value obtained in the 16 blade fan. In addition, the outlet mass flow rate increased by 45% with the increase in the number of blade from 16 to 32. There is no significant change observed on the suction pressure and outlet mass flow rate when the number of blades increased from 32 to 48. In the light of the analysis results, the optimum blade number was determined as 32.

Keywords: blade type, centrifugal fan, cfd, outlet mass flow rate, suction pressure

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11691 Investigation of Time Pressure and Instinctive Reaction in Moral Dilemmas While Driving

Authors: Jacqueline Miller, Dongyuan Y. Wang, F. Dan Richard

Abstract:

Before trying to make an ethical machine that holds a higher ethical standard than humans, a better understanding of human moral standards that could be used as a guide is crucial. How humans make decisions in dangerous driving situations like moral dilemmas can contribute to developing acceptable ethical principles for autonomous vehicles (AVs). This study uses a driving simulator to investigate whether drivers make utilitarian choices (choices that maximize lives saved and minimize harm) in unavoidable automobile accidents (moral dilemmas) with time pressure manipulated. This study also investigates how impulsiveness influences drivers’ behavior in moral dilemmas. Manipulating time pressure results in collisions that occur at varying time intervals (4 s, 5 s, 7s). Manipulating time pressure helps investigate how time pressure may influence drivers’ response behavior. Thirty-one undergraduates participated in this study using a STISM driving simulator to respond to driving moral dilemmas. The results indicated that the percentage of utilitarian choices generally increased when given more time to respond (from 4 s to 7 s). Additionally, participants in vehicle scenarios preferred responding right over responding left. Impulsiveness did not influence utilitarian choices. However, as time pressure decreased, response time increased. Findings have potential implications and applications on the regulation of driver assistance technologies and AVs.

Keywords: time pressure, automobile moral dilemmas, impulsiveness, reaction time

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11690 Literature Review and Biomechanical Findings in Patients with Bipartite Medial Cuneiforms

Authors: Aliza Lee, Mark Wilt, John Bonk, Scott Floyd, Bradley Hoffman, Karen Uchmanowicz

Abstract:

Bipartite medial cuneiforms are relatively rare but may play a significant role in biomechanical and gait abnormalities. It is believed that a bipartite medial cuneiform may alter the available range of motion due to its larger morphological variant, thus limiting the metatarsal plantarflexion needed to achieve adequate hallux dorsiflexion for normal gait. Radiographic and clinical assessments were performed on 2 patients who reported foot pain along the first ray. Both patients had visible bipartite medial cuneiforms on MRI. Using gait plate and Metascan™ analysis, both were noted to have four measurements far beyond the expected range. Medial and lateral heel peak pressure, hallux peak pressure, and 1st metatarsal peak pressure were all noted to be increased. These measurements are believed to be increased due to the hindrance placed on the available ROM of the 1st ray by the increased size of the medial cuneiform. A larger patient population would be needed to fully understand this developmental anomaly.

Keywords: bipartite medial cuneiforms, cuneiform, developmental anomaly, gait abnormality

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11689 [Keynote Speech]: Experimental Study on the Effects of Water-in-Oil Emulsions to the Pressure Drop in Pipeline Flow

Authors: S. S. Dol, M. S. Chan, S. F. Wong, J. S. Lim

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Emulsion formation is unavoidable and can be detrimental to an oil field production. The presence of stable emulsions also reduces the quality of crude oil and causes more problems in the downstream refinery operations, such as corrosion and pipeline pressure drop. Hence, it is important to know the effects of emulsions in the pipeline. Light crude oil was used for the continuous phase in the W/O emulsions where the emulsions pass through a flow loop to test the pressure drop across the pipeline. The results obtained shows that pressure drop increases as water cut is increased until it peaks at the phase inversion of the W/O emulsion between 30% to 40% water cut. Emulsions produced by gradual constrictions show a lower stability as compared to sudden constrictions. Lower stability of emulsions in gradual constriction has the higher influence of pressure drop compared to a sudden sharp decrease in diameter in sudden constriction. Generally, sudden constriction experiences pressure drop of 0.013% to 0.067% higher than gradual constriction of the same ratio. Lower constriction ratio cases cause larger pressure drop ranging from 0.061% to 0.241%. Considering the higher profitability in lower emulsion stability and lower pressure drop at the developed flow region of different constrictions, an optimum design of constriction is found to be gradual constriction with a ratio of 0.5.

Keywords: constriction, pressure drop, turbulence, water-in-oil emulsions

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11688 Evaluation Using a Bidirectional Microphone as a Pressure Pulse Wave Meter

Authors: Shunsuke Fujiwara, Takashi Kaburagi, Kazuyuki Kobayashi, Kajiro Watanabe, Yosuke Kurihara

Abstract:

This paper describes a novel sensor device, a pressure pulse wave meter, which uses a bidirectional condenser microphone. The microphone work as a microphone as well as a sensor with high gain over a wide frequency range; they are also highly reliable and economical. Currently aging is becoming a serious social issue in Japan causing increased medical expenses in the country. Hence, it is important for elderly citizens to check health condition at home, and to care the health conditions through daily monitoring. Given this circumstances, we developed a novel pressure pulse wave meter based on a bidirectional condenser microphone. This novel pressure pulse wave meter device is used as a measuring instrument of health conditions.

Keywords: bidirectional microphone, pressure pulse wave meter, health condition, novel sensor device

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11687 Education of Mothers and Influence on the Development of Intrauterine Growth Restriction

Authors: Sabina Garayeva

Abstract:

To determine the significant risk factors for intrauterine growth restriction (IUGR), we carried out a thorough study of the social status of the parents of children with IUGR. We observed 315 mothers who gave birth to children with (IUGR), of which 172 mothers with asymmetric type and 143 mothers with symmetric type of IUGR. Through a detailed survey was gathered detailed information about education of parents. The results show that the majority of mothers with IUGR had secondary education (44,8 ± 2,8%), and fathers - higher education (35,2 ± 2,7%). Whereas in the control group, the largest number of parents had higher education (mother 35,3 ± 4,4%, fathers 42,9 ± 4,5%). Number of mothers with secondary education with IUGR was significantly (p1 <0,01; χ2 = 22,67) differs from the number of mothers with physiological pregnancy with the same level of education. Meanwhile, in the group with a symmetrical embodiment of IUGR mothers with secondary formation of significantly greater 53,1 ± 4,2%, than the asymmetric embodiment IUGR 37,8 ± 3,7% (p2 <0,05; χ2 = 8 06). Among fathers with secondary education significant difference was noted in the symmetric version of IUGR 37,8 ± 4,1% more than in the control group (p1 <0,05), and among parents of children with asymmetric IUGR option prevailed fathers with higher education - 37 2 ± 3,7%. Thus, our results revealed a low educational level of the mother as a risk factor for IUGR, which further help to develop preventive and therapeutic measures to eliminate the severity of its consequences. As seen from the data presented, mothers of children with asymmetric IUGR had a school education and fathers - higher education, while in the symmetric type of both parents had secondary education. It is found that frequency of children, born with IUGR, of mothers - housewives and fathers, engage in physical labor, was high. Thus, the analysis conducted by the social status of the parents with IUGR revealed a low level of education and unemployed mothers as risk factors for this disease, which in the future will help to develop preventive and therapeutic measures to eliminate the severity of its.

Keywords: intrauterine growth restriction, education of mothers, education influence, IUGR

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11686 Effects of Injection Conditions on Flame Structures in Gas-Centered Swirl Coaxial Injector

Authors: Wooseok Song, Sunjung Park, Jongkwon Lee, Jaye Koo

Abstract:

The objective of this paper is to observe the effects of injection conditions on flame structures in gas-centered swirl coaxial injector. Gaseous oxygen and liquid kerosene were used as propellants. For different injection conditions, two types of injector, which only differ in the diameter of the tangential inlet, were used in this study. In addition, oxidizer injection pressure was varied to control the combustion chamber pressure in different types of injector. In order to analyze the combustion instability intensity, the dynamic pressure was measured in both the combustion chamber and propellants lines. With the increase in differential pressure between the propellant injection pressure and the combustion chamber pressure, the combustion instability intensity increased. In addition, the flame structure was recorded using a high-speed camera to detect CH* chemiluminescence intensity. With the change in the injection conditions in the gas-centered swirl coaxial injector, the flame structure changed.

Keywords: liquid rocket engine, flame structure, combustion instability, dynamic pressure

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11685 Massive Intrapartum Hemorrhage Following by Inner Myometrial Laceration during a Vaginal Delivery: A Rare Case Report

Authors: Bahareh Khakifirooz, Arian Shojaei, Amirhossein Hajialigol, Bahare Abdolahi

Abstract:

Laceration of the inner layer of the myometrium can cause massive bleeding during and after childbirth, which can lead to the death of the mother if it is not diagnosed in time. We studied a rare case of massive intrapartum bleeding following myometrial laceration that was diagnosed correctly, and the patient survived with in-time treatments. The patient was a 26 years-old woman who was under observation for term pregnancy and complaint of rupture of membranes (ROM) and vaginal bleeding. Following the spontaneous course of labor and without receiving oxytocin, during the normal course of labor, she had an estimated total blood loss of 750 mL bleeding, which, despite the normal fetal heart rate and with the mother's indication for cesarean section, was transferred to the operating room and underwent cesarean section. During the cesarean section, the amniotic fluid was clear; after the removal of the placenta, severe and clear bleeding was flowing from the posterior wall of the uterus, which was caused by the laceration of the inner layer of the myometrium in the posterior wall of the lower segment of the uterus. The myometrial laceration was repaired with absorbable continuous locked sutures, and hemostasis was established, then, the patient used uterotonic drugs, and after monitoring, the patient was discharged from the hospital in good condition.

Keywords: intrapartum hemorrhage, inner myometrial laceration, labor, Increased intrauterine pressure

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11684 Deformation Analysis of Pneumatized Sphenoid Bone Caused Due to Elevated Intracranial Pressure Using Finite Element Analysis

Authors: Dilesh Mogre, Jitendra Toravi, Saurabh Joshi, Prutha Deshpande, Aishwarya Kura

Abstract:

In earlier days of technology, it was not possible to understand the nature of complex biomedical problems and were only left to clinical postulations. With advancement in science today, we have tools like Finite Element Modelling and simulation to solve complex biomedical problems. This paper presents how ANSYS WORKBENCH can be used to study deformation of pneumatized sphenoid bone caused by increased intracranial pressure. Intracranial pressure refers to the pressure inside the skull. The increase in the pressure above the normal range of 15mmhg can lead to serious conditions due to developed stresses and deformation. One of the areas where the deformation is suspected to occur is Sphenoid Bone. Moreover, the varying degree of pneumatization increases the complexity of the conditions. It is necessary to study deformation patterns on pneumatized sphenoid bone model at elevated intracranial pressure. Finite Element Analysis plays a major role in developing and analyzing model and give quantitative results.

Keywords: intracranial pressure, pneumatized sphenoid bone, deformation, finite element analysis

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11683 Combination of Plantar Pressure and Star Excursion Balance Test for Evaluation of Dynamic Posture Control on High-Heeled Shoes

Authors: Yan Zhang, Jan Awrejcewicz, Lin Fu

Abstract:

High-heeled shoes force the foot into plantar flexion position resulting in foot arch rising and disturbance of the articular congruence between the talus and tibiofibular mortice, all of which may increase the challenge of balance maintenance. Plantar pressure distribution of the stance limb during the star excursion balance test (SEBT) contributes to the understanding of potential sources of reaching excursions in SEBT. The purpose of this study is to evaluate the dynamic posture control while wearing high-heeled shoes using SEBT in a combination of plantar pressure measurement. Twenty healthy young females were recruited. Shoes of three heel heights were used: flat (0.8 cm), low (4.0 cm), high (6.6 cm). The testing grid of SEBT consists of three lines extending out at 120° from each other, which were defined as anterior, posteromedial, and posterolateral directions. Participants were instructed to stand on their dominant limb with the heel in the middle of the testing grid and hands on hips and to reach the non-stance limb as far as possible towards each direction. The distal portion of the reaching limb lightly touched the ground without shifting weight. Then returned the reaching limb to the beginning position. The excursion distances were normalized to leg length. The insole plantar measurement system was used to record peak pressure, contact area, and pressure-time integral of the stance limb. Results showed that normalized excursion distance decreased significantly as heel height increased. The changes of plantar pressure in SEBT as heel height increased were more obvious in the medial forefoot (MF), medial midfoot (MM), rearfoot areas. At MF, the peak pressure and pressure-time integral of low and high shoes increased significantly compared with that of flat shoes, while the contact area decreased significantly as heel height increased. At MM, peak pressure, contact area, and pressure-time integral of high and low shoes were significantly lower than that of flat shoes. To reduce posture instability, the stance limb plantar loading shifted to medial forefoot. Knowledge of this study identified dynamic posture control deficits while wearing high-heeled shoes and the critical role of the medial forefoot in dynamic balance maintenance.

Keywords: dynamic posture control, high-heeled shoes, plantar pressure, star excursion balance test.

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11682 Improving the Performance of DBE Structure in Pressure Flushing Using Submerged Vanes

Authors: Sepideh Beiramipour, Hadi Haghjouei, Kourosh Qaderi, Majid Rahimpour, Mohammad M. Ahmadi, Sameh A. Kantoush

Abstract:

Reservoir sedimentation is one of the main challenges by which the reservoir behind the dam is filled with sediments transferred through the river flow. Pressure flushing method is an effective way to drain the deposited sediments of the reservoirs through the bottom outlet. So far, several structural methods have been proposed to increase the efficiency of pressure flushing. The aim of this study is to increase the performance of Dendritic Bottomless Extended (DBE) structure on the efficiency of pressurized sediment flushing using submerged vanes. For this purpose, the physical model of the dam reservoir with dimensions of 7.5 m in length, 3.5 m in width, and 1.8 m in height in the hydraulic and water structures research laboratory of Shahid Bahonar University of Kerman was used. In order to investigate the influence of submerged vanes on the performance of DBE structure in pressure flushing, the best arrangement and geometric parameters of the vanes were selected and combined with the DBE structure. The results showed that the submerged vanes significantly increased the performance of the DBE structure so that the volume of the sediment flushing cone with the combination of two structures increased by 3.7 times compared to the DBE structure test.

Keywords: dendritic bottomless extended structure, flushing efficiency, sedimentation, sediment flushing

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11681 Improving the Design of Blood Pressure and Blood Saturation Monitors

Authors: L. Parisi

Abstract:

A blood pressure monitor or sphygmomanometer can be either manual or automatic, employing respectively either the auscultatory method or the oscillometric method. The manual version of the sphygmomanometer involves an inflatable cuff with a stethoscope adopted to detect the sounds generated by the arterial walls to measure blood pressure in an artery. An automatic sphygmomanometer can be effectively used to monitor blood pressure through a pressure sensor, which detects vibrations provoked by oscillations of the arterial walls. The pressure sensor implemented in this device improves the accuracy of the measurements taken.

Keywords: blood pressure, blood saturation, sensors, actuators, design improvement

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11680 Effect of Acute Ingestion of Ice Water on Blood Pressure in Relation to Body Mass Index

Authors: Savitri Siddanagoudra, Shantala Herlekar, Priya Arjunwadekar

Abstract:

Background: The physiological response to water drinking in healthy subjects is an integrated response with an increase in sympathetic vasoconstrictor activity with induced bradycardia. Obesity is a modern pandemic, implicated in the pathogenesis of cardiovascular disease. In autonomic failure patients, water drinking has been shown the increased high blood pressure and bradycardia. Acute effects of ice water ingestion on blood pressure (BP) in relation to body mass index (BMI) is not addressed in literature. Objectives: Objective of this study is to evaluate BP before and after ingestion of cold water in all the three groups. Methods and Material: 60 healthy subjects between the age group of 18-24 yrs were selected and assigned into 3 groups based on BMI. BMI less than and equal to 25 kg/m2 is selected as Normal BMI group ,between 25- 29 kg/m2 as Overweight and BMI more than and equal to 30 kg/m2 as Obese. Procedure: Basal and after ingestion of 250 ml of cold water (7 0C ± 0.5 0C)BP was recorded in all the 3 groups. Results: Basal and after ice water ingestion BP increased statistically in all 3 groups. Conclusion: On acute ingestion of ice water overweight, obese may have more sympathoexcitaion compared to normal subjects.

Keywords: blood pressure, body mass index, ice water, symathoexcitation

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11679 Components of Arterial Pressure and Its Association with Dietary Inflammatory Potential of Older Individuals: The Multinational Medis Study

Authors: Demosthenes Panagiotakos

Abstract:

The aim of the present work was to evaluate dietary habits’ inflammatory potential with various components of arterial blood pressure (hypertension, mean arterial pressure (MAP) and pulse pressure (PP)) in a sample of older Mediterranean people without known cardiovascular disease. During 2005-2011, 2,813 older (aged 65-100 years) individuals from 21 Mediterranean islands and the rural Mani region (Peloponnesus) were voluntarily enrolled. Standard procedures were used to determine arterial blood pressure, as well as PP and MAP, and for the evaluation of dietary habits, lifestyle, anthropometric and clinical characteristics of the participants. A dietary inflammatory index (DII) was assessed based on the participants specific dietary habits, and its calculation was based on a standard procedure. It was reported that the higher the DII level of a diet (adherence to a more pro-inflammatory diet) the greater was the likelihood of having an older adult hypertension [OR=3.82 (95% CI): 1.24 to 11.71]. Moreover, the higher the level of DII (more pro-inflammatory dietary habits) the greater were the levels of MAP [b-coefficient (95% CI): 7.23 (+1.86 to +12.59)] and PP, [b-coefficient (95% CI): 10.86 (+2.70 to +19.01)]. Diet’s inflammatory potential is related with various components of arterial pressure. Adherence to a more pro-inflammatory diet seems to be associated with increased arterial peripheral resistance and arterial stiffness.

Keywords: dietary inflammatory index, hypertension, mean arterial pressure, elderly

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11678 High Pressure Multiphase Flow Experiments: The Impact of Pressure on Flow Patterns Using an X-Ray Tomography Visualisation System

Authors: Sandy Black, Calum McLaughlin, Alessandro Pranzitelli, Marc Laing

Abstract:

Multiphase flow structures of two-phase multicomponent fluids were experimentally investigated in a large diameter high-pressure pipeline up to 130 bar at TÜV SÜD’s National Engineering Laboratory Advanced Multiphase Facility. One of the main objectives of the experimental test campaign was to evaluate the impact of pressure on multiphase flow patterns as much of the existing information is based on low-pressure measurements. The experiments were performed in a horizontal and vertical orientation in both 4-inch and 6-inch pipework using nitrogen, ExxsolTM D140 oil, and a 6% aqueous solution of NaCl at incremental pressures from 10 bar to 130 bar. To visualise the detailed structure of the flow of the entire cross-section of the pipe, a fast response X-ray tomography system was used. A wide range of superficial velocities from 0.6 m/s to 24.0 m/s for gas and 0.04 m/s and 6.48 m/s for liquid was examined to evaluate different flow regimes. The results illustrated the suppression of instabilities between the gas and the liquid at the measurement location and that intermittent or slug flow was observed less frequently as the pressure was increased. CFD modellings of low and high-pressure simulations were able to successfully predict the likelihood of intermittent flow; however, further tuning is necessary to predict the slugging frequency. The dataset generated is unique as limited datasets exist above 100 bar and is of considerable value to multiphase flow specialists and numerical modellers.

Keywords: computational fluid dynamics, high pressure, multiphase, X-ray tomography

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