Search results for: iliac vein compression syndrome
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 1876

Search results for: iliac vein compression syndrome

826 Some Hematological Parameters of the Mauremys rivulata in Two Different Water Quality in the Biga Stream (Çanakkale, Turkey)

Authors: Cigdem Gul, Murat Tosunoglu, Nurcihan Hacioglu

Abstract:

The contamination or desiccation of fresh waters also has a negative effect on freshwater turtles like other fresh water-dependent species. In order to conserve those species, which are confronted with such negative conditions, it is necessary to know beforehand the biology and the physiology of species. In this study, a comprehensive health assessment was conducted on a total of 20 clinically normal individuals free living Western Caspian Turtle (Mauremys rivulata) captured from two different freshwater localities in the Biga stream (Çanakkale-Turkey). When comparing our findings with the Turkish legislation (Water pollution control regulation), the 1. Locality of the Biga stream in terms of total coliform classified as "high quality water" (Coliform: 866.66 MPN/100 mL), while the 2. Locality was a “contaminated water" (Coliform: 53266.66 MPN/100 mL). Blood samples for hematological and biochemical analyses were obtained from the dorsal coccygeal vein. A total of 1-2 mL of blood was collected from each of the specimens via needle. After the required procedures had been performed, the turtles were put back in the same localities. Hematological and biochemical analyses based on high quality water and contaminated water, respectively, are as follows: Red blood cell count (512600-582666.66 per cubic millimeter of blood), white blood cell count (5920-5980 per cubic millimeter of blood), hematocrit value (24-24.66 %), hemoglobin concentration (6.52-6.35 g/dl), mean corpuscular volume (466.20-468.98 fl), mean corpuscular hemoglobin (125.77-113.84 pg), mean corpuscular hemoglobin concentration (28.25-26.49 %), glucose (94.43-87.43 mg/dl), creatinine (0.23-0.3241 mg/dl), uric acid (12.59-10.48 mg/L), albumin (1.46-1.25 g/dl), calcium (8.67-9.59 mg/dl), triglyceride (95.55-75.21 mg/dl), and total protein (4.85-3.45 g/dl). When an examination was made depending on the water quality of freshwater, variations were detected in hematology and biochemistry values, but not found significant difference.

Keywords: biochemistry, freshwater quality, hematological parameters, Mauremys rivulata.

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825 The Relationship between Size of Normal and Cystic Bovine Ovarian Follicles with Follicular Fluid Levels of Nitric Oxide and Estradiol

Authors: Hamidreza Khodaei, Behnaz Mahdavi, Leila Karshenas

Abstract:

Nitric oxide (NO) is a small fast acting neurotransmitter, which is synthesized From L-arginine by nitric oxide synthase. Studies show that NO affects a wide range of reproductive functions. Steroidal hormones synthesis, LH surge during ovulation, follicular growth and ovulation are all affected by NO. Therefore, the objective of this study was to evaluate the relationship between NO and estradiol (E2) production in ovarian follicles and cysts in bovines. Two experiment groups were formed and serum and follicular fluid levels Of NO and estradiol (E2) was measured. In the first group, follicular fluids were obtained from 30 slaughtered cows. Follicles were divided into three groups according to follicular diameter: Small follicles, <5 mm, medium-sized follicles, 5 to 10 mm, and large follicles, >10 mm. 30 follicles were randomly selected within each group. Blood samples were obtained via jugular vein. NO concentrations in blood and ovarian follicular fluids were measured by Griess reaction method and radio-immunoassay respectively. In the second group: 12 cows in follicular phase and with cystic follicles were selected and a cystic follicle was obtained from each. NO and E2 levels were measured as done for the first experiment group. The data were analyzed by SAS software using ANOVA and Duncan’s test. NO concentrations of follicular fluids from large follicles were significantly higher than those of the medium and small-sized ones. There were significant differences in the concentrations of nitrite and nitrate (Stable metabolites of NO) between large and cystic follicles, with extremely low NO and high E2 levels in cystic follicles (p<0.01).The results suggest that paracrine effects of NO may play an important role in the control of ovarian follicle growth and development of cystic follicles in bovines. It seems that NO dictates its effects through inhibition of ovarian steroidal synthesis.

Keywords: nitric oxide, estradiol, cystic follicle, cow, oogenesis, oocyte maturation, follicular fluid

Procedia PDF Downloads 234
824 Microarrays: Wide Clinical Utilities and Advances in Healthcare

Authors: Salma M. Wakil

Abstract:

Advances in the field of genetics overwhelmed detecting large number of inherited disorders at the molecular level and directed to the development of innovative technologies. These innovations have led to gene sequencing, prenatal mutation detection, pre-implantation genetic diagnosis; population based carrier screening and genome wide analyses using microarrays. Microarrays are widely used in establishing clinical and diagnostic setup for genetic anomalies at a massive level, with the advent of cytoscan molecular karyotyping as a clinical utility card for detecting chromosomal aberrations with high coverage across the entire human genome. Unlike a regular karyotype that relies on the microscopic inspection of chromosomes, molecular karyotyping with cytoscan constructs virtual chromosomes based on the copy number analysis of DNA which improves its resolution by 100-fold. We have been investigating a large number of patients with Developmental Delay and Intellectual disability with this platform for establishing micro syndrome deletions and have detected number of novel CNV’s in the Arabian population with the clinical relevance.

Keywords: microarrays, molecular karyotyping, developmental delay, genetics

Procedia PDF Downloads 458
823 Effects of Anti-FGL2 Monoclonal Antibody SPF89 on Vascular Inflammation

Authors: Ying Sun, Biao Cheng, Qing Lu, Xuefei Tao, Xiaoyu Lai, Cheng Guo, Dan Wang

Abstract:

Fibrinogen-like protein 2 (FGL2) has recently been identified to play an important role in inflammatory diseases such as atherosclerosis through a thrombin-dependent manner. Here, a murine monoclonal antibody was raised against the critical residue Ser(89) of FGL2, and the effects of the anti-FGL2 mAb (SPF89) were analyzed in human umbilical vein endothelial cells (HUVECs) and THP-1 cells. Firstly, it was proved that SPF89, which belongs to the IgG1 subtype with a KD value of 44.5 pM, could specifically show the expression levels of protein FGL2 in different cell lines of known target gene status. The lipopolysaccharide (LPS)-mediated endothelial cell proliferation was significantly inhibited with a decline of phosphorylation nuclear factor-κB (NF-κB) in a dose-dependent manner after SPF89 treatment. Furthermore, SPF89 reduced LPS-induced expression of adhesion molecules and inflammatory cytokines such as vascular cell adhesion molecule-1, tumor necrosis factor-α, Matrix metalloproteinase MMP-2, Integrin αvβ3, and interleukin-6 in HUVECs. In macrophage-like THP-1 cells, SPF89 effectively inhibited LPS and low-density lipoprotein-induced foam cell formation. However, these anti-inflammatory and anti-atherosclerotic effects of anti-FGL2 mAb in HUVECs and THP-1 cells were significantly reduced after treatment with an NF-κB inhibitor PDTC. All the above suggest, by efficiently inhibiting LPS-induced pro-inflammatory effects in vascular endothelial cells by attenuating NF-κB dependent pathway, the new anti-FGL2 mAb SPF89 could to be a potential therapeutic candidate for protecting the vascular endothelium against inflammatory diseases such as atherosclerosis. This work was supported by the Program of Sichuan Science and Technology Department (2017FZ0069) and Collaborative Innovation Program of Sichuan for Elderly Care and Health(YLZBZ1511).

Keywords: monoclonal antibody, fibrinogen like protein 2, inflammation, endothelial cells

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822 Study of Biomechanical Model for Smart Sensor Based Prosthetic Socket Design System

Authors: Wei Xu, Abdo S. Haidar, Jianxin Gao

Abstract:

Prosthetic socket is a component that connects the residual limb of an amputee with an artificial prosthesis. It is widely recognized as the most critical component that determines the comfort of a patient when wearing the prosthesis in his/her daily activities. Through the socket, the body weight and its associated dynamic load are distributed and transmitted to the prosthesis during walking, running or climbing. In order to achieve a good-fit socket for an individual amputee, it is essential to obtain the biomechanical properties of the residual limb. In current clinical practices, this is achieved by a touch-and-feel approach which is highly subjective. Although there have been significant advancements in prosthetic technologies such as microprocessor controlled knee and ankle joints in the last decade, the progress in designing a comfortable socket has been rather limited. This means that the current process of socket design is still very time-consuming, and highly dependent on the expertise of the prosthetist. Supported by the state-of-the-art sensor technologies and numerical simulations, a new socket design system is being developed to help prosthetists achieve rapid design of comfortable sockets for above knee amputees. This paper reports the research work related to establishing biomechanical models for socket design. Through numerical simulation using finite element method, comprehensive relationships between pressure on residual limb and socket geometry were established. This allowed local topological adjustment for the socket so as to optimize the pressure distributions across the residual limb. When the full body weight of a patient is exerted on the residual limb, high pressures and shear forces between the residual limb and the socket occur. During numerical simulations, various hyperplastic models, namely Ogden, Yeoh and Mooney-Rivlin, were used, and their effectiveness in representing the biomechanical properties of soft tissues of the residual limb was evaluated. This also involved reverse engineering, which resulted in an optimal representative model under compression test. To validate the simulation results, a range of silicone models were fabricated. They were tested by an indentation device which yielded the force-displacement relationships. Comparisons of results obtained from FEA simulations and experimental tests showed that the Ogden model did not fit well the soft tissue material indentation data, while the Yeoh model gave the best representation of the soft tissue mechanical behavior under indentation. Compared with hyperplastic model, the result showed that elastic model also had significant errors. In addition, normal and shear stress distributions on the surface of the soft tissue model were obtained. The effect of friction in compression testing and the influence of soft tissue stiffness and testing boundary conditions were also analyzed. All these have contributed to the overall goal of designing a good-fit socket for individual above knee amputees.

Keywords: above knee amputee, finite element simulation, hyperplastic model, prosthetic socket

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821 Design of a 28-nm CMOS 2.9-64.9-GHz Broadband Distributed Amplifier with Floating Ground CPW

Authors: Tian-Wei Huang, Wei-Ting Bai, Yu-Tung Cheng, Jeng-Han Tsai

Abstract:

In this paper, a 1-stage 6-section conventional distributed amplifier (CDA) structure distributed power amplifier (DPA) fabricated in a 28-nm HPC+ 1P9M CMOS process is proposed. The transistor size selection is introduced to achieve broadband power matching and thus remains a high flatness output power and power added efficiency (PAE) within the bandwidth. With the inductive peaking technique, the high-frequency pole appears and the high-frequency gain is increased; the gain flatness becomes better as well. The inductive elements used to form an artificial transmission line are built up with a floating ground coplanar waveguide plane (CPWFG) rather than a microstrip line, coplanar waveguide (CPW), or spiral inductor to get better performance. The DPA achieves 12.6 dB peak gain at 52.5 GHz with 2.9 to 64.9 GHz 3-dB bandwidth. The Psat is 11.4 dBm with PAEMAX of 10.6 % at 25 GHz. The output 1-dB compression point power is 9.8 dBm.

Keywords: distributed power amplifier (DPA), gain bandwidth (GBW), floating ground CPW, inductive peaking, 28-nm, CMOS, 5G.

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820 Ergonomical Study of Hand-Arm Vibrational Exposure in a Gear Manufacturing Plant in India

Authors: Santosh Kumar, M. Muralidhar

Abstract:

The term ‘ergonomics’ is derived from two Greek words: ‘ergon’, meaning work and ‘nomoi’, meaning natural laws. Ergonomics is the study of how working conditions, machines and equipment can be arranged in order that people can work with them more efficiently. In this research communication an attempt has been made to study the effect of hand-arm vibrational exposure on the workers of a gear manufacturing plant by comparison of potential Carpal Tunnel Syndrome (CTS) symptoms and effect of different exposure levels of vibration on occurrence of CTS in actual industrial environment. Chi square test and correlation analysis have been considered for statistical analysis. From Chi square test, it has been found that the potential CTS symptoms occurrence is significantly dependent on the level of vibrational exposure. Data analysis indicates that 40.51% workers having potential CTS symptoms are exposed to vibration. Correlation analysis reveals that potential CTS symptoms are significantly correlated with exposure to level of vibration from handheld tools and to repetitive wrist movements.

Keywords: CTS symptoms, hand-arm vibration, ergonomics, physical tests

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819 Effect of Probiotic (RE3) Supplement on Growth Performance, Diarrhea Incidence and Blood Parameters of N'dama Calves

Authors: Y. Abdul Aziz, E. L. K. Osafo, S. O. Apori, A. Osman

Abstract:

A sixteen week trial was conducted at the Research Farm (Technology Village) of the Department of Animal Science, School of Agriculture, University of Cape Coast, Cape Coast, Ghana. This study sought to investigate the effects of Probiotic (RE3) on growth performance, diarrhea incidence and blood parameters of N’dama calves. Sixteen N’dama calves aged 3 months of an average initial weight of 44.2 kg were randomly assigned to one of four dietary treatments according to their body weight, age, and sex. Treatment 1 (T1) serve as a control animal (No RE3 supplementation). Treatment 2 (T2) receives 0.03 ml RE3 per kg body weight. Treatment 3 (T3) receives 0.06 ml RE3 per kg body weight, and Treatment 4 (T4) also receives 0.09 ml RE3 per kg body weight in a Completely Randomize Design (CRD). There were 4 replicates per treatment. The calves were allowed access to feed and water ad libitum. The body weight of the calves was recorded at the start of the experiment and thereafter regularly at two weeks interval. Weighing was done early morning before the calves are allowed to access feed and water and were also observed in their pens for occurrence of diarrhea and faecal scores recorded. Blood samples were obtained from each calf at the end of the study through jugular vein puncture. Supplementation of RE3 to calves had showed a beneficial effect by reducing the incidence of diarrhea. The highest faecal score was recorded in T1 and the least faecal score was recorded in T3. There was significant difference (P < 0.05) in the faecal score between the treatment group and the control after two weeks of the experiment. There was no significant difference (P > 0.05) in the average daily gain of the animals. Hematological and biochemical indices of calves were all within the normal range except in treatments (1, 3 and 4) which recorded high White Blood Cell (WBC) count with no significant difference (P > 0.05).

Keywords: probiotics (RE3), diarrhea incidence, blood parameters, N’dama calves

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818 Formulation of Famotidine Solid Lipid Nanoparticles (SLN): Preparation, Evaluation and Release Study

Authors: Rachmat Mauludin, Nurmazidah

Abstract:

Background and purpose: Famotidine is an H2 receptor blocker. Absorption orally is rapid enough, but famotidine can be degraded by stomach acid causing dose reduction until 35.8% after 50 minutes. This drug also undergoes first-pass metabolism which reduced its bio availability only until 40-50%. To overcome these problems, Solid Lipid Nano particles (SLNs) as alternative delivery systems can be formulated. SLNs is a lipid-based drug delivery technology with 50-1000 nm particle size, where the drug incorporated into the bio compatible lipids and the lipid particles are stabilized using appropriate stabilizers. When the particle size is 200 nm or below, lipid containing famotidine can be absorbed through the lymphatic vessels to the subclavian vein, so first-pass metabolism can be avoided. Method: Famotidine SLNs with various compositions of stabilizer was prepared using a high-speed homogenization and sonication method. Then, the particle size distribution, zeta potential, entrapment efficiency, particle morphology and in vitro release profiles were evaluated. Optimization of sonication time also carried out. Result: Particle size of SLN by Particle Size Analyzer was in range 114.6 up to 455.267 nm. Ultrasonicated SLNs within 5 minutes generated smaller particle size than SLNs which was ultrasonicated for 10 and 15 minutes. Entrapment efficiency of SLNs were 74.17 up to 79.45%. Particle morphology of the SLNs was spherical and distributed individually. Release study of Famotidine revealed that in acid medium, 28.89 up to 80.55% of famotidine could be released after 2 hours. Nevertheless in basic medium, famotidine was released 40.5 up to 86.88% in the same period. Conclusion: The best formula was SLNs which stabilized by 4% Poloxamer 188 and 1 % Span 20, that had particle size 114.6 nm in diameter, 77.14% famotidine entrapped, and the particle morphology was spherical and distributed individually. SLNs with the best drug release profile was SLNs which stabilized by 4% Eudragit L 100-55 and 1% Tween 80 which had released 36.34 % in pH 1.2 solution, and 74.13% in pH 7.4 solution after 2 hours. The optimum sonication time was 5 minutes.

Keywords: famotodine, SLN, high speed homogenization, particle size, release study

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817 Confinement of Concrete Filled Steel Tubular Beams Using U-Links

Authors: Madiha Z. Ammari, Abdul Qader AlNajmi

Abstract:

A new system of U-links was used in this study to confine the concrete core in concrete-filled steel beams. This system aims to employ the separation expected between the steel tube and the concrete core in the compression side of the section in the plastic hinge zone. A total of six rectangular CFT beam specimens were tested under flexure using different D/t ratios and different diameters for the U-links to examine their effect on the flexural behavior of these beams. The ultimate flexural strength of the CFT beam specimens with U-links showed an increase of strength about 47% of the specimen with D/t ratio equals 37.5 above standard CFT beam specimen without U-links inside. State of concrete inside the tubes has shown no crushing of concrete when those beams were cut open at the location of the plastic hinge. Strain measurements revealed that the compressive strain of concrete was 5-6 times the concrete crushing strain.

Keywords: concrete-filled tubes, U-links, plated studies, beams, flexural strength, concrete, confinement

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816 Effect of Compaction and Degree of Saturation on the Unconsolidated Undrained Shear Strength of Sandy Clay

Authors: Fatima Mehmood, Khalid Farooq, Rabeea Bakhtawer

Abstract:

For geotechnical engineers, one of the most important properties of soil to consider in various stability analyses is its shear strength which is governed by a number of factors. The objective of this research is to ascertain the effect of compaction and degree of saturation on the shear strength of fine-grained soil. For this purpose, three different dry densities such as in-situ, maximum standard proctor, and maximum modified proctor, were determined for the sandy clay soil. The soil samples were then prepared to keep dry density constant and varying degrees of saturation. These samples were tested for (UU) unconsolidated undrained shear strength in triaxial compression tests. The decrease in shear strength was observed with the decrease in density and increase in the saturation. The values of the angle of internal friction followed the same trend. However, the change in cohesion with the increase in saturation showed a different behavior, analogous to the compaction curve.

Keywords: compaction, degree of saturation, dry density, geotechnical investigation, laboratory testing, shear strength

Procedia PDF Downloads 137
815 A Robust Digital Image Watermarking Against Geometrical Attack Based on Hybrid Scheme

Authors: M. Samadzadeh Mahabadi, J. Shanbehzadeh

Abstract:

This paper presents a hybrid digital image-watermarking scheme, which is robust against varieties of attacks and geometric distortions. The image content is represented by important feature points obtained by an image-texture-based adaptive Harris corner detector. These feature points are extracted from LL2 of 2-D discrete wavelet transform which are obtained by using the Harris-Laplacian detector. We calculate the Fourier transform of circular regions around these points. The amplitude of this transform is rotation invariant. The experimental results demonstrate the robustness of the proposed method against the geometric distortions and various common image processing operations such as JPEG compression, colour reduction, Gaussian filtering, median filtering, and rotation.

Keywords: digital watermarking, geometric distortions, geometrical attack, Harris Laplace, important feature points, rotation, scale invariant feature

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814 Effects of Heat Treatment on the Elastic Constants of Cedar Wood

Authors: Tugba Yilmaz Aydin, Ergun Guntekin, Murat Aydin

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Effects of heat treatment on the elastic constants of cedar wood (Cedrus libani) were investigated. Specimens were exposed to heat under atmospheric pressure at four different temperatures (120, 150, 180, 210 °C) and three different time levels (2, 5, 8 hours). Three Young’s modulus (EL, ER, ET) and six Poisson ratios (μLR, μLT, μRL, μRT, μTL, μTR) were determined from compression test using bi-axial extensometer at constant moisture content (12 %). Three shear modulus were determined using ultrasound. Six shear wave velocities propagating along the principal axes of anisotropy were measured using EPOCH 650 ultrasonic flaw detector with 1 MHz transverse transducers. The properties of the samples tested were significantly affected by heat treatment by different degree. As a result, softer treatments yielded some amount of increase in Young modulus and shear modulus values, but increase of time and temperature resulted in significant decrease for both values. Poisson ratios seemed insensitive to heat treatment.

Keywords: cedar wood, elastic constants, heat treatment, ultrasound

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813 Seroprevalence of Middle East Respiratory Syndrome Coronavirus (MERS-Cov) Infection among Healthy and High Risk Individuals in Qatar

Authors: Raham El-Kahlout, Hadi Yassin, Asmaa Athani, Marwan Abou Madi, Gheyath Nasrallah

Abstract:

Background: Since its first isolation in September 2012, Middle East respiratory syndrome coronavirus (MERS-CoV) has diffused across 27 countries infecting more than two thousand individuals with a high case fatality rate. MERS-CoV–specific antibodies are widely found in Dromedary camel along with viral shedding of similar viruses detected in human at same region, suggesting that MERS epidemiology may be central role by camel. Interestingly, MERS-CoV has also been also reported to be asymptomatic or to cause influenza-like mild illnesses. Therefore, in a country like Qatar (bordered Saudi Arabia), where camels are widely spread, serological surveys are important to explore the role of camels in MERS-CoV transmission. However, widespread strategic serological surveillances of MERS-CoV among populations, particularly in endemic country, are infrequent. In the absence of clear epidemiological view, cross-sectional MERS antibody surveillances in human populations are of global concern. Method: We performed a comparative serological screening of 4719 healthy blood donors, 135 baseline case contacts (high risk individual), and four MERS confirmed patients (by PCR) for the presence of anti-MERS IgG. Initially, samples were screened using Euroimmune anti- MERS-CoV IgG ELISA kit, the only commercial kit available in the market and recommended by the CDC as a screening kit. To confirm ELISA test results, farther serological testing was performed for all borderline and positive samples using two assays; the anti MERS-CoV IgG and IgM Euroimmune indirect immunofluorescent test (IIFT) and pseudoviral particle neutralizing assay (PPNA). Additionally, to test cross reactivity of anti-MERS-CoV antibody with other family members of coronavirus, borderline and positive samples were tested for the presence of the of IgG antibody of the following viruses; SARS, HCoV-229E, HKU1 using the Euroimmune IIFT for SARS and HCoV-229E and ELISA for HKU1. Results: In all of 4858 screened 15 samples [10 donors (0.21%, 10/4719), 1 case contact (0.77 %, 1/130), 3 patients (75%, 3/4)] anti-MERS IgG reactive/borderline samples were seen in ELISA. However, only 7 (0.14%) of them gave positive with in IIFT and only 3 (0.06%) was confirmed by the specific anti-MERS PPNA. One of the interesting findings was, a donor, who was selected in the control group as a negative anti-MERS IgG ELISA, yield reactive for anti-MERS IgM IIFT and was confirmed with the PPNA. Further, our preliminary results showed that there was a strong cross reactivity between anti- MERS-COV IgG with both HCoV-229E or anti-HKU1 IgG, yet, no cross reactivity of SARS were found. Conclusions: Our findings suggest that MERS-CoV is not heavily circulated among the population of Qatar and this is also indicated by low number of confirmed cases (only 18) since 2012. Additionally, the presence of antibody of other pathogenic human coronavirus may cause false positive results of both ELISA and IIFT, which stress the need for more evaluation studies for the available serological assays. Conclusion: this study provides an insight about the epidemiological view for MERS-CoV in Qatar population. It also provides a performance evaluation for the available serologic tests for MERS-CoV in a view of serologic status to other human coronaviruses.

Keywords: seroprevalence, MERS-CoV, healthy individuals, Qatar

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812 Evaluation of Critical State Behavior of Granular Soil in Confined Compression Tests

Authors: Rabia Chaudhry, Andrew Dawson

Abstract:

Identification of steady/critical state of coarse granular soil is challenging at conventional pressures. This study examines the drained and undrained triaxial tests for large strains on loose to dense, uniformly graded, Leighton Buzzard Fraction A sand. The triaxial tests are conducted under controlled test conditions. The comparison of soil behavior on shear strength characteristics at different effective stresses has been studied at the medium to large strains levels and the uniqueness of the critical state was discussed. The test results showed that there were two steady/critical state lines for drained and undrained conditions at confining pressures less than 1000 kPa. A critical state friction angle is not constant and the overall scatter in the steady/critical state line for the tested sand is ±0.01 in terms of void ratio at stress levels less than 1000 kPa.

Keywords: critical state, stress strain behavior, fabric/structure, triaxial tests

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811 A Low-Power, Low-Noise and High-Gain 58~66 GHz CMOS Receiver Front-End for Short-Range High-Speed Wireless Communications

Authors: Yo-Sheng Lin, Jen-How Lee, Chien-Chin Wang

Abstract:

A 60-GHz receiver front-end using standard 90-nm CMOS technology is reported. The receiver front-end comprises a wideband low-noise amplifier (LNA), and a double-balanced Gilbert cell mixer with a current-reused RF single-to-differential (STD) converter, an LO Marchand balun and a baseband amplifier. The receiver front-end consumes 34.4 mW and achieves LO-RF isolation of 60.7 dB, LO-IF isolation of 45.3 dB and RF-IF isolation of 41.9 dB at RF of 60 GHz and LO of 59.9 GHz. At IF of 0.1 GHz, the receiver front-end achieves maximum conversion gain (CG) of 26.1 dB at RF of 64 GHz and CG of 25.2 dB at RF of 60 GHz. The corresponding 3-dB bandwidth of RF is 7.3 GHz (58.4 GHz to 65.7 GHz). The measured minimum noise figure was 5.6 dB at 64 GHz, one of the best results ever reported for a 60 GHz CMOS receiver front-end. In addition, the measured input 1-dB compression point and input third-order inter-modulation point are -33.1 dBm and -23.3 dBm, respectively, at 60 GHz. These results demonstrate the proposed receiver front-end architecture is very promising for 60 GHz direct-conversion transceiver applications.

Keywords: CMOS, 60 GHz, direct-conversion transceiver, LNA, down-conversion mixer, marchand balun, current-reused

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810 An Assessment of Drainage Network System in Nigeria Urban Areas using Geographical Information Systems: A Case Study of Bida, Niger State

Authors: Yusuf Hussaini Atulukwu, Daramola Japheth, Tabitit S. Tabiti, Daramola Elizabeth Lara

Abstract:

In view of the recent limitations faced by the township concerning poorly constructed and in some cases non - existence of drainage facilities that resulted into incessant flooding in some parts of the community poses threat to life,property and the environment. The research seeks to address this issue by showing the spatial distribution of drainage network in Bida Urban using Geographic information System techniques. Relevant features were extracted from existing Bida based Map using un-screen digitization and x, y, z, data of existing drainages were acquired using handheld Global Positioning System (GPS). These data were uploaded into ArcGIS 9.2, software, and stored in the relational database structure that was used to produce the spatial data drainage network of the township. The result revealed that about 40 % of the drainages are blocked with sand and refuse, 35 % water-logged as a result of building across erosion channels and dilapidated bridges as a result of lack of drainage along major roads. The study thus concluded that drainage network systems in Bida community are not in good working condition and urgent measures must be initiated in order to avoid future disasters especially with the raining season setting in. Based on the above findings, the study therefore recommends that people within the locality should avoid dumping municipal waste within the drainage path while sand blocked or weed blocked drains should be clear by the authority concerned. In the same vein the authority should ensured that contract of drainage construction be awarded to professionals and all the natural drainages caused by erosion should be addressed to avoid future disasters.

Keywords: drainage network, spatial, digitization, relational database, waste

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809 Variation in the Morphology of Soft Palate

Authors: Hema Lattupalli

Abstract:

Introduction: The palate forms a partition between the oral cavity and nasal cavity. The palate is made up of two parts hard palate and soft palate. The Hard palate forms the anterior part of the palate, the soft palate forms a movable muscular fold covered by mucous membrane that is suspended from the posterior border of a hard palate. Aim and Objectives: Soft palate morphological variations have a great paucity in the literature. It’s also believed that the soft palate has no such important anatomical variations. There is a variable presentation of the soft palate morphology in the lateral cephalograms. The aim of this study is to identify the velar morphology. Materials and Methods: 100 normal subjects between the age group of 20 – 35 were taken for the study. Method: Lateral Cephalogram (radiologic study). Results: Different shapes of the soft palate were observed in the lateral cephalograms. The morphology of soft palate was classified into six types 1.Leaf like (50 cases) most common type, 2.Straight line (20 cases), 3.S shaped (4 cases) very rare, 4.Butt like (10 cases), 5. Rat tail (6 cases), 6. Hook shaped (10 cases). Conclusion: This classification helps us to understand the better diversity of the velar morphology in mid-sagittal plane. These findings help us to understand the etiology of OSAS.

Keywords: soft palate, cephalometric radiographs, morphology, cleft palate, obstructive sleep apnoea syndrome

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808 The Optimization Process of Aortic Heart Valve Stent Geometry

Authors: Arkadiusz Mezyk, Wojciech Klein, Mariusz Pawlak, Jacek Gnilka

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The aortic heart valve stents should fulfill many criterions. These criteria have a strong impact on the geometrical shape of the stent. Usually, the final construction of stent is a result of many year experience and knowledge. Depending on patents claims, different stent shapes are produced by different companies. This causes difficulties for biomechanics engineers narrowing the domain of feasible solutions. The paper present optimization method for stent geometry defining by a specific analytical equation based on various mathematical functions. This formula was implemented as APDL script language in ANSYS finite element environment. For the purpose of simulation tests, a few parameters were separated from developed equation. The application of the genetic algorithms allows finding the best solution due to selected objective function. Obtained solution takes into account parameters such as radial force, compression ratio and coefficient of expansion on the transverse axial.

Keywords: aortic stent, optimization process, geometry, finite element method

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807 Spatially Encoded Hyperspectral Compressive Microscope for Broadband VIS/NIR Imaging

Authors: Lukáš Klein, Karel Žídek

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Hyperspectral imaging counts among the most frequently used multidimensional sensing methods. While there are many approaches to capturing a hyperspectral data cube, optical compression is emerging as a valuable tool to reduce the setup complexity and the amount of data storage needed. Hyperspectral compressive imagers have been created in the past; however, they have primarily focused on relatively narrow sections of the electromagnetic spectrum. A broader spectral study of samples can provide helpful information, especially for applications involving the harmonic generation and advanced material characterizations. We demonstrate a broadband hyperspectral microscope based on the single-pixel camera principle. Captured spatially encoded data are processed to reconstruct a hyperspectral cube in a combined visible and near-infrared spectrum (from 400 to 2500 nm). Hyperspectral cubes can be reconstructed with a spectral resolution of up to 3 nm and spatial resolution of up to 7 µm (subject to diffraction) with a high compressive ratio.

Keywords: compressive imaging, hyperspectral imaging, near-infrared spectrum, single-pixel camera, visible spectrum

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806 Effect of Elastic Modulus Anisotropy on Helical Piles Behavior in Sandy Soil

Authors: Reza Ziaie Moayed, Javad Shamsi Soosahab

Abstract:

Helical piles are being used extensively in engineering applications all over the world. There are insufficient studies on the helical piles' behavior in anisotropic soils. In this paper, numerical modeling was adopted to investigate the effect of elastic modulus anisotropy on helical pile behavior resting on anisotropic sand by using a finite element limit analysis. The load-displacement behavior of helical piles under compression and tension loads is investigated in different relative densities of soils, and the effect of the ratio of horizontal elastic modulus with respect to vertical elastic modulus (EH/EV) is evaluated. The obtained results illustrate that in sandy soils, the anisotropic ratio of elastic modulus (EH/EV) has notable effect on bearing capacity of helical piles in different relative density. Therefore, it may be recommended that the effect of anisotropic condition of soil elastic modulus should be considered in helical piles behavior.

Keywords: helical piles, bearing capacity, numerical modeling, soil anisotropy

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805 Integration of Immigrant Students into Local Education System

Authors: Suheyla Demi̇rkol Orak

Abstract:

The requirement of inclusive education is one of the utmost important results of both regular and irregular immigration. The matter in the case of Syrian immigrants is even worse than the other immigrants cases in world history since a massive immigration wave has affected all world countries' socio-economic profiles. When Syrians immigrated from Syria all over the world, they aimed to survive and left behind the war, but surviving is not optional occasion without handling language-related problems. Humans exist and preserve their existence with their language. That is a matter of concern for the integration of Syrians into the hosting countries. Many countries are proceeding with various programs to integrate Syrians into the majority groups by either assimilation or adaptation policies. Turkey has got the lion's share of the Syrian immigration apple, and in the same vein with this situation, its language education system should be analyzed severely in order to come up with a perfect match program for the integration of Syrians. It aimed to generate an inclusive education model for catalyzing the integration process of immigrant Syrian students into the majority socio-economic group via overcoming the language barrier. The identity of the immigrants is prioritized. The study follows a narrative literature review, which aims to review and critique relevant literature and offers a new conceptualization derived from the previous literature. The study derives a critical localized bilingual education model. As the outcome of the narrative literature review, a bilingual education model which prioritized the identity of the target community was designed. In the present study, main bilingual education programs and most of the countries' bilingual education policies were reviewed critically and suggestions were listed for the Syrian immigrants dominantly in Turkey and suggested to be benefitted by the other countries through localizing the practices.

Keywords: bi/multilingual education, sheltered education, immigrants, glocalization, submersion program, immersion program

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804 Effect of Non-Crimp Fabric Structure on Mechanical Properties of Laminates

Authors: Hireni R. Mankodi, D. J. Chudasama

Abstract:

The textile preforms play a key role in providing the mechanical properties and gives the idea about selection parameter of preforms to improve the quality and performance of laminates. The main objectives of this work are to study the effect of non-crimp fabric preform structure in final properties of laminates. It has been observed that the multi-axial preform give better mechanical properties of laminates as compared to woven and biaxial fabrics. This study investigated the effect of different non-crimp glass preform structure on tensile strength, bending and compression properties of glass laminates. The different woven, bi-axial and multi-axial fabrics with similar GSM used to manufacture the laminates using polyester resin. The structural and mechanical properties of preform and laminates were studied using standard methods. It has been observed that the glass fabric geometry, including type of weaves, warps and filling density and number of layer plays significant role in deciding mechanical properties of laminates.

Keywords: preform, non-crimp structure, laminates, bi-axial, multiaxial

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803 Rd-PLS Regression: From the Analysis of Two Blocks of Variables to Path Modeling

Authors: E. Tchandao Mangamana, V. Cariou, E. Vigneau, R. Glele Kakai, E. M. Qannari

Abstract:

A new definition of a latent variable associated with a dataset makes it possible to propose variants of the PLS2 regression and the multi-block PLS (MB-PLS). We shall refer to these variants as Rd-PLS regression and Rd-MB-PLS respectively because they are inspired by both Redundancy analysis and PLS regression. Usually, a latent variable t associated with a dataset Z is defined as a linear combination of the variables of Z with the constraint that the length of the loading weights vector equals 1. Formally, t=Zw with ‖w‖=1. Denoting by Z' the transpose of Z, we define herein, a latent variable by t=ZZ’q with the constraint that the auxiliary variable q has a norm equal to 1. This new definition of a latent variable entails that, as previously, t is a linear combination of the variables in Z and, in addition, the loading vector w=Z’q is constrained to be a linear combination of the rows of Z. More importantly, t could be interpreted as a kind of projection of the auxiliary variable q onto the space generated by the variables in Z, since it is collinear to the first PLS1 component of q onto Z. Consider the situation in which we aim to predict a dataset Y from another dataset X. These two datasets relate to the same individuals and are assumed to be centered. Let us consider a latent variable u=YY’q to which we associate the variable t= XX’YY’q. Rd-PLS consists in seeking q (and therefore u and t) so that the covariance between t and u is maximum. The solution to this problem is straightforward and consists in setting q to the eigenvector of YY’XX’YY’ associated with the largest eigenvalue. For the determination of higher order components, we deflate X and Y with respect to the latent variable t. Extending Rd-PLS to the context of multi-block data is relatively easy. Starting from a latent variable u=YY’q, we consider its ‘projection’ on the space generated by the variables of each block Xk (k=1, ..., K) namely, tk= XkXk'YY’q. Thereafter, Rd-MB-PLS seeks q in order to maximize the average of the covariances of u with tk (k=1, ..., K). The solution to this problem is given by q, eigenvector of YY’XX’YY’, where X is the dataset obtained by horizontally merging datasets Xk (k=1, ..., K). For the determination of latent variables of order higher than 1, we use a deflation of Y and Xk with respect to the variable t= XX’YY’q. In the same vein, extending Rd-MB-PLS to the path modeling setting is straightforward. Methods are illustrated on the basis of case studies and performance of Rd-PLS and Rd-MB-PLS in terms of prediction is compared to that of PLS2 and MB-PLS.

Keywords: multiblock data analysis, partial least squares regression, path modeling, redundancy analysis

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802 Behavior Study of Concrete-Filled Thin-Walled Square Hollow Steel Stub Columns

Authors: Mostefa Mimoune

Abstract:

Test results on concrete-filled steel tubular stub columns under axial compression are presented. The study was mainly focused on square hollow section SHS columns; 27 columns were tested. The main experimental parameters considered were the thickness of the tube, columns length and cross section sizes. Existing design codes and theoretical model were used to predict load-carrying capacities of composite section to compare the accuracy of the predictions by using the recommendations of DTR-BC (Algerian code), CSA (Canadian standard), AIJ, EC4, DBJ, AISC, BS and EC4. Experimental results indicate that the studied parameters have significant influence on both the compressive load capacity and the column failure mode. All codes used in the comparison, provide higher resistance compared to those of tests. Equation method has been suggested to evaluate the axial capacity of the composite section seem to be in agreement with tests.

Keywords: axial loading, composite section, concrete-filled steel tubes, square hollow section

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801 Thermomechanical Processing of a CuZnAl Shape-Memory Alloy

Authors: Pedro Henrique Alves Martins, Paulo Guilherme Ferreira De Siqueira, Franco De Castro Bubani, Maria Teresa Paulino Aguilar, Paulo Roberto Cetlin

Abstract:

Cu-base shape-memory alloys (CuZnAl, CuAlNi, CuAlBe, etc.) are promising engineering materials for several unconventional devices, such as sensors, actuators, and mechanical vibration dampers. Brittleness is one of the factors that limit the commercial use of these alloys, as it makes thermomechanical processing difficult. In this work, a method for the hot extrusion of a 75.50% Cu, 16,74% Zn, 7,76% Al (weight %) alloy is presented. The effects of the thermomechanical processing in the microstructure and the pseudoelastic behavior of the alloy are assessed by optical metallography, compression and hardness tests. Results show that hot extrusion is a suitable method to obtain severe cross-section reductions in the CuZnAl shape-memory alloy studied. The alloy maintained its pseudoelastic effect after the extrusion and the modifications in the mechanical behavior caused by precipitation during hot extrusion can be minimized by a suitable precipitate dissolution heat treatment.

Keywords: hot extrusion, pseudoelastic, shape-memory alloy, thermomechanical processing

Procedia PDF Downloads 374
800 Formulation Development and Evaluation of Floating Tablets of Venlafaxine Hydrochloride

Authors: Gajera Lalit, Shah Pranav, Shah Shailesh

Abstract:

Venlafaxine hydrochloride has a short elimination half-life of 5 ± 2 hr, and absorption window in the upper part of gastrointestinal tract. The conventional tablets need to be administered two to three times a day and possess an oral bioavailability of 45%. The purpose of this study was to formulate gastroretentive effervescent floating tablets of Venlafaxine HCl. Different grades of HPMC namely K15M, K4M, K100M and E15LV were employed as swelling polymers whereas sodium bicarbonate was employed as gas generating agent. The direct compression method was employed for the formulation of tablets. The tablets were evaluated in terms of hardness, friability, weight variation, drug content, water uptake, in-vitro floating behavior and in-vitro drug release study. All the formulations exhibited very short floating lag time of < 1 min and total floating time of 12 hr. Formulation L3 containing 25 mg and 75 mg of HPMC E15 LV and HPMC K15M respectively exhibited complete drug release within 12 hrs.

Keywords: venlafaxine HCl, hydroxyl propyl methylcellulose, floating gastro retentive tablets, in-vitro drug release, non-fickian diffusion

Procedia PDF Downloads 543
799 Experimental Studies on Prestressed Precast Concrete Bridge Piers

Authors: C. Shim, C. Koem, S. Park, S. Lee

Abstract:

This paper deals with experimental studies on pre stressed precast concrete columns with continuous reinforcing bars and pre stressing tendons. Design requirements on minimum transverse reinforcement ratio are not included in current design codes. Pre stressing introduces additional compression to the column. Precast columns with different transverse reinforcement ratios were tested to derive adequate design requirement. Displacement ductility of the pre stressed precast columns was evaluated and compared with previous studies. Design of axial steels including reinforcing bars and pre stressing tendons influenced on the seismic performance. Without significant increase of transverse reinforcement ratio, the specimens showed required displacement ductility without reduction of their flexural strength. Design recommendations for precast bridge piers were derived.

Keywords: displacement ductility, flexural strength, prestressed precast column, transverse reinforcement

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798 Engineering Parameters and Classification of Marly Soils of Tabriz

Authors: Amirali Mahouti, Hooshang Katebi

Abstract:

Enlargement of Tabriz metropolis to the east and north-east caused urban construction to be built on Marl layers and because of increase in excavations depth, further information of this layer is inescapable. Looking at geotechnical investigation shows there is not enough information about Tabriz Marl and this soil has been classified only by color. Tabriz Marl is lacustrine carbonate sediment outcrops, surrounds eastern, northern and southern region of city in the East Azerbaijan Province of Iran and is known as bed rock of city under alluvium sediments. This investigation aims to characterize geotechnical parameters of this soil to identify and set it in classification system of carbonated soils. For this purpose, specimens obtained from 80 locations over the city and subjected to physical and mechanical tests, such as Atterberg limits, density, moisture content, unconfined compression, direct shear and consolidation. CaCO3 content, organic content, PH, XRD, XRF, TGA and geophysical downhole tests also have been done on some of them.

Keywords: carbonated soils, classification of soils, mineralogy, physical and mechanical tests for Marls, Tabriz Marl

Procedia PDF Downloads 318
797 Energy Analysis of an Ejector Based Solar Assisted Trigeneration System for Dairy Application

Authors: V. Ravindra, P. A. Saikiran, M. Ramgopal

Abstract:

This paper presents an energy analysis of a solar assisted trigeneration system using an Ejector for dairy applications. The working fluid in the trigeneration loop is Supercritical CO₂. The trigeneration system is a combination of Brayton cycle and ejector based vapor compression refrigeration cycle. The heating and cooling outputs are used for simultaneous pasteurization and chilling of the milk. The electrical power is used to drive the auxiliary equipment in the dairy plant. A numerical simulation is done with Engineering Equation Solver (EES), and a parametric analysis is performed by varying the operating variables over a meaningful range. The results show that the overall performance index decreases with increase in ambient temperature. For an ejector based system, the compressor work and cooling output are significant output quantities. An increase in total mass flow rate of the refrigerant (primary + secondary) results in an increase in the compressor work and cooling output.

Keywords: trigeneration, solar thermal, supercritical CO₂, ejector

Procedia PDF Downloads 124