Search results for: vulval skin condition
2865 Microstructure and Mechanical Properties of Boron-Containing AZ91D Mg Alloys
Authors: Ji Chan Kim, Seok Hong Min, Tae Kwon Ha
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Effect of boron addition on the microstructure and mechanical properties of AZ91D Mg alloy was investigated in this study. Through calculation of phase equilibria, carried out by using FactSage® and FTLite database, solution treatment temperature was decided as 420 °C where supersaturated solid solution can be obtained. Solid solution treatment was conducted at 420 °C for 24 hrs followed by hot rolling at 420 °C and the total reduction was about 60%. Recrystallization heat treatment was followed at 420 °C for 6 hrs to obtain equiaxed microstructure. After recrystallization treatment, aging heat treatment was conducted at temperature of 200 °C for time intervals from 1 min to 200 hrs and hardness of each condition was measured by micro-Vickers method. Peak hardness was observed after 20 hrs. Tensile tests were also conducted on the specimens aged for various time intervals and the results were compared with hardness.Keywords: AZ91D Mg alloy, boron, heat treatment, microstructure, mechanical properties, hardness
Procedia PDF Downloads 3162864 Effect of Nigella Sativa Seeds and Ajwa Date on Blood Glucose Level in Saudi Patients with Type 2 Diabetes Mellitus
Authors: Reham Algheshairy, Khaled Tayeb, Christopher Smith, Rebecca Gregg, Haruna Musa
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Background: Diabetes is a medical condition that refers to the pancreas’ inability to secrete sufficient insulin levels, a hormone responsible for controlling glucose levels in the body. Any surplus glucose in the blood stream is excreted through the urinary system. Insulin resistance in blood cells can also cause this condition despite the fact that the pancreas is producing the required amount of insulin A number of researchers claim that the prevalence of diabetes in Saudi Arabia has reached epidemic proportions, although one study did observe one positive in the rise in the awareness of diabetes, possibly indicative of Saudi Arabia’s improving healthcare system. While a number of factors can cause diabetes, the ever-increasing incidence of the disease in Saudi Arabia has been blamed primarily on low levels of physical activity and high levels of obesity. Objectives: The project has two aims. The first aim of the project is to investigate the regulatory effects of consumption of Nigella seeds and Ajwah dates on blood glucose levels in diabetic patients with type 2 diabetes. The second aim of the project is to investigate whether these dietary factors may have potentially beneficial effects in controlling the complications that associated with type 2 diabetes. Methods: This use a random-cross intervention trail of 75 Saudi male and female with type 2 diabetes in Al-Noor hospital in Makkah ( KSA) aged between 18 and 70 years were divided into 3 groups. Group 1 will consume 2g of Nigella Sativa seeds daily along with a modified diet for 12 weeks, group 2 will be given Ajwah dates daily with a modified diet for 12 weeks and group 3 will follow a modified diet for 12 weeks. Anthropometric measurements were taken at baseline, along with bloods for HbA1c, fasting blood sugar and at the end of 12 weeks. Results: This study found significant decrease in blood level (FBG & 2PPBG) and HbA1c in the groups with diet and Nigella seeds) compared to Ajwa date. However, there is no significant change were found in HbA1c, FBG and 2hrpp regarding Ajwa group. Conclusion: This study illustrated a significant improvement in some markers of glycaemia following 2 g of Ns and diet for 12 weeks. The dose of 2g/day of consumed Nigella seeds was found to be more effective in controlling BGL and HbA1c than control and Ajwa groups. This suggests that Nigella seeds and following a diet may have a potential effect (a role in controlling outcomes for type 2 diabetes and controlling the disease). Further research is needed on a large scale to determine the optimum dose and duration of Nigella and Ajwa in order to achieve the desired results.Keywords: type 2 diabetes, Nigella seeds, Ajwa dates, fasting blood glucose, control
Procedia PDF Downloads 2952863 A Machine Learning Approach for Assessment of Tremor: A Neurological Movement Disorder
Authors: Rajesh Ranjan, Marimuthu Palaniswami, A. A. Hashmi
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With the changing lifestyle and environment around us, the prevalence of the critical and incurable disease has proliferated. One such condition is the neurological disorder which is rampant among the old age population and is increasing at an unstoppable rate. Most of the neurological disorder patients suffer from some movement disorder affecting the movement of their body parts. Tremor is the most common movement disorder which is prevalent in such patients that infect the upper or lower limbs or both extremities. The tremor symptoms are commonly visible in Parkinson’s disease patient, and it can also be a pure tremor (essential tremor). The patients suffering from tremor face enormous trouble in performing the daily activity, and they always need a caretaker for assistance. In the clinics, the assessment of tremor is done through a manual clinical rating task such as Unified Parkinson’s disease rating scale which is time taking and cumbersome. Neurologists have also affirmed a challenge in differentiating a Parkinsonian tremor with the pure tremor which is essential in providing an accurate diagnosis. Therefore, there is a need to develop a monitoring and assistive tool for the tremor patient that keep on checking their health condition by coordinating them with the clinicians and caretakers for early diagnosis and assistance in performing the daily activity. In our research, we focus on developing a system for automatic classification of tremor which can accurately differentiate the pure tremor from the Parkinsonian tremor using a wearable accelerometer-based device, so that adequate diagnosis can be provided to the correct patient. In this research, a study was conducted in the neuro-clinic to assess the upper wrist movement of the patient suffering from Pure (Essential) tremor and Parkinsonian tremor using a wearable accelerometer-based device. Four tasks were designed in accordance with Unified Parkinson’s disease motor rating scale which is used to assess the rest, postural, intentional and action tremor in such patient. Various features such as time-frequency domain, wavelet-based and fast-Fourier transform based cross-correlation were extracted from the tri-axial signal which was used as input feature vector space for the different supervised and unsupervised learning tools for quantification of severity of tremor. A minimum covariance maximum correlation energy comparison index was also developed which was used as the input feature for various classification tools for distinguishing the PT and ET tremor types. An automatic system for efficient classification of tremor was developed using feature extraction methods, and superior performance was achieved using K-nearest neighbors and Support Vector Machine classifiers respectively.Keywords: machine learning approach for neurological disorder assessment, automatic classification of tremor types, feature extraction method for tremor classification, neurological movement disorder, parkinsonian tremor, essential tremor
Procedia PDF Downloads 1542862 A Review of Fractal Dimension Computing Methods Applied to Wear Particles
Authors: Manish Kumar Thakur, Subrata Kumar Ghosh
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Various types of particles found in lubricant may be characterized by their fractal dimension. Some of the available methods are: yard-stick method or structured walk method, box-counting method. This paper presents a review of the developments and progress in fractal dimension computing methods as applied to characteristics the surface of wear particles. An overview of these methods, their implementation, their advantages and their limits is also present here. It has been accepted that wear particles contain major information about wear and friction of materials. Morphological analysis of wear particles from a lubricant is a very effective way for machine condition monitoring. Fractal dimension methods are used to characterize the morphology of the found particles. It is very useful in the analysis of complexity of irregular substance. The aim of this review is to bring together the fractal methods applicable for wear particles.Keywords: fractal dimension, morphological analysis, wear, wear particles
Procedia PDF Downloads 4902861 Structural Analysis of Hydro-Turbine Spiral Casing and Stay Ring Using Ansys
Authors: Surjit Angra, Pooja Rani, Vinod Kumar
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In hydro power plant spiral casing and Stay ring is meant to guide the water flow to guide vane and runner. Spiral casing and Stay ring is subjected to static i.e. pressure load as well as fluctuating load acting on the structure due to water hammer effect in water conductor system. Finite element method has been used to calculate stresses on spiral casing and stay ring. These calculations were done for the maximum possible loading under operating condition "LC1 Quick Shut Down”. The design load is reached for the spiral casing and stay ring during the emergency closure of the guide apparatus "LC1 Quick Shut Down”. During this operation the forces from the head cover to the stay ring also reach their maximum.Keywords: hydro-turbine, spiral casing, stay ring, structural analysis
Procedia PDF Downloads 5162860 Gender Inequality in the Nigerian Labour Market as a Cause of Unemployment among Female Graduates
Authors: Temitope Faloye
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The absence of equity and transparency in Nigeria's economic system has resulted in unemployment. Women’s unemployment rate remains higher because women's range of jobs is often narrower due to discriminatory attitudes of employers and gender segregation in the labor market. Gender inequality is one of the strong factors of unemployment, especially in developing countries like Nigeria, where the female gender is marginalized in the labor force market. However, gender equality in terms of labor market access and employment condition has not yet been attained. Feminist theory is considered as an appropriate theory for this study. The study will use a mixed-method design, collecting qualitative and quantitative data to provide answers to the research questions. Therefore, the research study aims to investigate the present situation of gender inequality in the Nigerian labor market.Keywords: unemployment, gender inequality, gender equality, labor market, female graduate
Procedia PDF Downloads 2422859 Efficient Iterative V-BLAST Detection Technique in Wireless Communication System
Authors: Hwan-Jun Choi, Sung-Bok Choi, Hyoung-Kyu Song
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Recently, among the MIMO-OFDM detection techniques, a lot of papers suggested V-BLAST scheme which can achieve high data rate. Therefore, the signal detection of MIMOOFDM system is important issue. In this paper, efficient iterative VBLAST detection technique is proposed in wireless communication system. The proposed scheme adjusts the number of candidate symbol and iterative scheme based on channel state. According to the simulation result, the proposed scheme has better BER performance than conventional schemes and similar BER performance of the QRD-M with iterative scheme. Moreover complexity of proposed scheme has 50.6 % less than complexity of QRD-M detection with iterative scheme. Therefore the proposed detection scheme can be efficiently used in wireless communication.Keywords: MIMO-OFDM, V-BLAST, QR-decomposition, QRDM, DFE, iterative scheme, channel condition
Procedia PDF Downloads 5302858 Predictive Modeling of Flank Wear in Hard Turning Using the Taguchi Method
Authors: Suha K. Shihab, Zahid A. Khan, Aas Mohammad, Arshad Noor Siddiquee
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This paper presents the influence of cutting parameters (cutting speed, feed and depth of cut) on flank wear (VB) in turning of 52100 hard alloy steel using multilayer coated carbide insert under dry condition. Nine experiments were performed based on Taguchi’s L9 orthogonal array. Analysis of variance (ANOVA) was used to determine the effects of the cutting parameters on flank wear. The results of the study revealed that the cutting speed (A) and feed rate (B) are the dominant factors affecting flank wear, while the depth of cut (C) has not a significant effect. The optimal combination of the cutting parameters for flank wear is found to be A1B1C1. The mathematical model for flank wear is found to be statistically significant. The predicted and measured values of flank wear are found to be very close to each other.Keywords: flank wear, hard turning, Taguchi approach, optimization
Procedia PDF Downloads 6642857 Differentiation of the Functional in an Optimization Problem for Coefficients of Elliptic Equations with Unbounded Nonlinearity
Authors: Aigul Manapova
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We consider an optimal control problem in the higher coefficient of nonlinear equations with a divergent elliptic operator and unbounded nonlinearity, and the Dirichlet boundary condition. The conditions imposed on the coefficients of the state equation are assumed to hold only in a small neighborhood of the exact solution to the original problem. This assumption suggests that the state equation involves nonlinearities of unlimited growth and considerably expands the class of admissible functions as solutions of the state equation. We obtain formulas for the first partial derivatives of the objective functional with respect to the control functions. To calculate the gradients the numerical solutions of the state and adjoint problems are used. We also prove that the gradient of the cost function is Lipchitz continuous.Keywords: cost functional, differentiability, divergent elliptic operator, optimal control, unbounded nonlinearity
Procedia PDF Downloads 1722856 Experimental Performance and Numerical Simulation of Double Glass Wall
Authors: Thana Ananacha
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This paper reports the numerical and experimental performances of Double Glass Wall are investigated. Two configurations were considered namely, the Double Clear Glass Wall (DCGW) and the Double Translucent Glass Wall (DTGW). The coupled governing equations as well as boundary conditions are solved using the finite element method (FEM) via COMSOLTM Multiphysics. Temperature profiles and flow field of the DCGW and DTGW are reported and discussed. Different constant heat fluxes were considered namely 400 and 800 W.m-2 the corresponding initial condition temperatures were to 30.5 and 38.5 ºC respectively. The results show that the simulation results are in agreement with the experimental data. Conclusively, the model considered in this study could reasonable be used simulate the thermal and ventilation performance of the DCGW and DTGW configurations.Keywords: thermal simulation, Double Glass Wall, velocity field, finite element method (FEM)
Procedia PDF Downloads 3592855 Transparency of Audit Firms in Croatia
Authors: Marko Čular
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The aim of this paper is to raise general awareness of transparency importance for audit firms and for audit services’ users. This paper analyses transparency of audit firms that audited financial statements of listed companies, for year 2011 and 2012. We use this two years because in the meantime Code of Ethics for Professional Accountants has been adopted. This paper investigates whether transparency reports of audit firms are in accordance with the Croatian Audit Act and whether there is a difference on transparency in observed years. For this paper, quality index of transparency report and financial indicators of audit firms are used to get conclusion about condition of audit firms transparency reporting. Results of our study indicate that audit firms are not fully transparent, looking for both years. Transparency of audit firms in 2012 has improved significantly, compared with transparency in 2011.Keywords: transparency report, index quality of transparency report, Croatian audit act, code of ethics for professional accountants
Procedia PDF Downloads 2982854 Post-Operative Pain Management in Ehlers-Danlos Hypermobile-Type Syndrome Following Wisdom Teeth Extraction: A Case Report and Literature Review
Authors: Aikaterini Amanatidou
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We describe the case of a 20-year-old female patient diagnosed with Ehlers-Danlos Syndrome (EDS) who was scheduled to undergo a wisdom teeth extraction in outpatient surgery. EDS is a hereditary connective tissue disorder characterized by joint hypermobility, skin hyper-extensibility, and vascular and soft tissue fragility. There are six subtypes of Ehlers-Danlos, and in our case, the patient had EDS hyper-mobility (HT) type disorder. One important clinical feature of this syndrome is chronic pain, which is often poorly understood and treated. Our patient had a long history of articular and lumbar pain when she was diagnosed. She was prescribed analgesic treatment for acute and neuropathic pain and had multiple sessions of psychotherapy and physiotherapy to ease the pain. Unfortunately, her extensive medical history was underrated by our anesthetic team, and no further measures were taken for the operation. Despite an uneventful intra-operative phase, the patient experienced several episodes of hyperalgesia during the immediate post-operative care. Management of pain was challenging for the anesthetic team: initial opioid treatment had only a temporary effect and a paradoxical reaction after a while. Final pain relief was eventually obtained with psycho-physiologic treatment, high doses of ketamine, and patient-controlled analgesia infusion of morphine-ketamine-dehydrobenzperidol. We suspected an episode of Opioid-Induced hyperalgesia. This case report supports the hypothesis that anti-hyperalgesics such as ketamine as well as lidocaine, and dexmedetomidine should be considered intra-operatively to avoid opioid-induced hyperalgesia and may be an alternative solution to manage complex chronic pain like others in neuropathic pain syndromes.Keywords: Ehlers-Danlos, post-operative management, hyperalgesia, opioid-induced hyperalgesia, rare disease
Procedia PDF Downloads 952853 Normal Weight Obesity among Female Students: BMI as a Non-Sufficient Tool for Obesity Assessment
Authors: Krzysztof Plesiewicz, Izabela Plesiewicz, Krzysztof Chiżyński, Marzenna Zielińska
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Background: Obesity is an independent risk factor for cardiovascular diseases. There are several anthropometric parameters proposed to estimate the level of obesity, but until now there is no agreement which one is the best predictor of cardiometabolic risk. Scientists defined metabolically obese normal weight, who suffer from metabolic abnormalities, the same as obese individuals, and defined this syndrome as normal weight obesity (NWO). Aim of the study: The aim of our study was to determine the occurrence of overweight and obesity in a cohort of young, adult women, using standard and complementary methods of obesity assessment and to indicate those, who are at risk of obesity. The second aim of our study was to test additional methods of obesity assessment and proof that body mass index using alone is not sufficient parameter of obesity assessment. Materials and methods: 384 young women, aged 18-32, were enrolled into the study. Standard anthropometric parameters (waist to hips ratio (WTH), waist to height ratio (WTHR)) and two other methods of body fat percentage measurement (BFPM) were used in the study: electrical bioimpendance analysis (BIA) and skinfold measurement test by digital fat body mass clipper (SFM). Results: In the study group 5% and 7% of participants had waist to hips ratio and accordingly waist to height ratio values connected with visceral obesity. According to BMI 14% participants were overweight and obese. Using additional methods of body fat assessment, there were 54% and 43% of obese for BIA and SMF method. In the group of participants with normal BMI and underweight (not overweight, n =340) there were individuals with the level of BFPM above the upper limit, for the BIA 49% (n =164) and for the SFM 36 % (n=125). Statistical analysis revealed strong correlation between BIA and SFM methods. Conclusion: BMI using alone is not a sufficient parameter of obesity assessment. High percentage of young women with normal BMI values seem to be normal weight obese.Keywords: electrical bioimpedance, normal weight obesity, skin-fold measurement test, women
Procedia PDF Downloads 2742852 Comprehensive Risk Assessment Model in Agile Construction Environment
Authors: Jolanta Tamošaitienė
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The article focuses on a developed comprehensive model to be used in an agile environment for the risk assessment and selection based on multi-attribute methods. The model is based on a multi-attribute evaluation of risk in construction, and the determination of their optimality criterion values are calculated using complex Multiple Criteria Decision-Making methods. The model may be further applied to risk assessment in an agile construction environment. The attributes of risk in a construction project are selected by applying the risk assessment condition to the construction sector, and the construction process efficiency in the construction industry accounts for the agile environment. The paper presents the comprehensive risk assessment model in an agile construction environment. It provides a background and a description of the proposed model and the developed analysis of the comprehensive risk assessment model in an agile construction environment with the criteria.Keywords: assessment, environment, agile, model, risk
Procedia PDF Downloads 2552851 Vertebrate Model to Examine the Biological Effectiveness of Different Radiation Qualities
Authors: Rita Emília Szabó, Róbert Polanek, Tünde Tőkés, Zoltán Szabó, Szabolcs Czifrus, Katalin Hideghéty
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Purpose: Several feature of zebrafish are making them amenable for investigation on therapeutic approaches such as ionizing radiation. The establishment of zebrafish model for comprehensive radiobiological research stands in the focus of our investigation, comparing the radiation effect curves of neutron and photon irradiation. Our final aim is to develop an appropriate vertebrate model in order to investigate the relative biological effectiveness of laser driven ionizing radiation. Methods and Materials: After careful dosimetry series of viable zebrafish embryos were exposed to a single fraction whole-body neutron-irradiation (1,25; 1,875; 2; 2,5 Gy) at the research reactor of the Technical University of Budapest and to conventional 6 MeV photon beam at 24 hour post-fertilization (hpf). The survival and morphologic abnormalities (pericardial edema, spine curvature) of each embryo were assessed for each experiment at 24-hour intervals from the point of fertilization up to 168 hpf (defining the dose lethal for 50% (LD50)). Results: In the zebrafish embryo model LD50 at 20 Gy dose level was defined and the same lethality were found at 2 Gy dose from the reactor neutron beam resulting RBE of 10. Dose-dependent organ perturbations were detected on macroscopic (shortening of the body length, spine curvature, microcephaly, micro-ophthalmia, micrognathia, pericardial edema, and inhibition of yolk sac resorption) and microscopic (marked cellular changes in skin, cardiac, gastrointestinal system) with the same magnitude of dose difference. Conclusion: In our observations, we found that zebrafish embryo model can be used for investigating the effects of different type of ionizing radiation and this system proved to be highly efficient vertebrate model for preclinical examinations.Keywords: ionizing radiation, LD50, relative biological effectiveness, zebrafish embryo
Procedia PDF Downloads 3092850 Strength Evaluation by Finite Element Analysis of Mesoscale Concrete Models Developed from CT Scan Images of Concrete Cube
Authors: Nirjhar Dhang, S. Vinay Kumar
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Concrete is a non-homogeneous mix of coarse aggregates, sand, cement, air-voids and interfacial transition zone (ITZ) around aggregates. Adoption of these complex structures and material properties in numerical simulation would lead us to better understanding and design of concrete. In this work, the mesoscale model of concrete has been prepared from X-ray computerized tomography (CT) image. These images are converted into computer model and numerically simulated using commercially available finite element software. The mesoscale models are simulated under the influence of compressive displacement. The effect of shape and distribution of aggregates, continuous and discrete ITZ thickness, voids, and variation of mortar strength has been investigated. The CT scan of concrete cube consists of series of two dimensional slices. Total 49 slices are obtained from a cube of 150mm and the interval of slices comes approximately 3mm. In CT scan images, the same cube can be CT scanned in a non-destructive manner and later the compression test can be carried out in a universal testing machine (UTM) for finding its strength. The image processing and extraction of mortar and aggregates from CT scan slices are performed by programming in Python. The digital colour image consists of red, green and blue (RGB) pixels. The conversion of RGB image to black and white image (BW) is carried out, and identification of mesoscale constituents is made by putting value between 0-255. The pixel matrix is created for modeling of mortar, aggregates, and ITZ. Pixels are normalized to 0-9 scale considering the relative strength. Here, zero is assigned to voids, 4-6 for mortar and 7-9 for aggregates. The value between 1-3 identifies boundary between aggregates and mortar. In the next step, triangular and quadrilateral elements for plane stress and plane strain models are generated depending on option given. Properties of materials, boundary conditions, and analysis scheme are specified in this module. The responses like displacement, stresses, and damages are evaluated by ABAQUS importing the input file. This simulation evaluates compressive strengths of 49 slices of the cube. The model is meshed with more than sixty thousand elements. The effect of shape and distribution of aggregates, inclusion of voids and variation of thickness of ITZ layer with relation to load carrying capacity, stress-strain response and strain localizations of concrete have been studied. The plane strain condition carried more load than plane stress condition due to confinement. The CT scan technique can be used to get slices from concrete cores taken from the actual structure, and the digital image processing can be used for finding the shape and contents of aggregates in concrete. This may be further compared with test results of concrete cores and can be used as an important tool for strength evaluation of concrete.Keywords: concrete, image processing, plane strain, interfacial transition zone
Procedia PDF Downloads 2402849 An Atomic Finite Element Model for Mechanical Properties of Graphene Sheets
Authors: Win-Jin Chang, Haw-Long Lee, Yu-Ching Yang
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In this study, we use the atomic-scale finite element method to investigate the mechanical behavior of the armchair- and zigzag-structured nanoporous graphene sheets with the clamped-free-free-free boundary condition under tension and shear loadings. The effect of porosity on Young’s modulus and shear modulus of nanoporous graphene sheets is obvious. For the armchair- and zigzag-structured nanoporous graphene sheets, Young’s modulus and shear modulus decreases with increasing porosity. Young’s modulus and shear modulus of zigzag graphene are larger than that of armchair one for the same porosity. The results are useful for application in the design of nanoporous graphene sheets.Keywords: graphene, nanoporous, Young's modulus, shear modulus
Procedia PDF Downloads 3972848 Range Suitability Model for Livestock Grazing in Taleghan Rangelands
Authors: Hossein Arzani, Masoud Jafari Shalamzari, Z. Arzani
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This paper follows FAO model of suitability analysis. Influential factors affecting extensive grazing were determined and converted into a model. Taleghan rangelands were examined for common types of grazing animals as an example. Advantages and limitations were elicited. All range ecosystems’ components affect range suitability but due to the time and money restrictions, the most important and feasible elements were investigated. From which three sub-models including water accessibility, forage production and erosion sensitivity were considered. Suitable areas in four levels of suitability were calculated using GIS. This suitability modeling approach was adopted due to its simplicity and the minimal time that is required for transforming and analyzing the data sets. Managers could be benefited from the model to devise the measures more wisely to cope with the limitations and enhance the rangelands health and condition.Keywords: range suitability, land-use, extensive grazing, modeling, land evaluation
Procedia PDF Downloads 3412847 Viscoelastic Characterization of Gelatin/Cellulose Nanocrystals Aqueous Bionanocomposites
Authors: Liliane Samara Ferreira Leite, Francys Kley Vieira Moreira, Luiz Henrique Capparelli Mattoso
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The increasing environmental concern regarding the plastic pollution worldwide has stimulated the development of low-cost biodegradable materials. Proteins are renewable feedstocks that could be used to produce biodegradable plastics. Gelatin, for example, is a cheap film-forming protein extracted from animal skin and connective tissues of Brazilian Livestock residues; thus it has a good potential in low-cost biodegradable plastic production. However, gelatin plastics are limited in terms of mechanical and barrier properties. Cellulose nanocrystals (CNC) are efficient nanofillers that have been used to extend physical properties of polymers. This work was aimed at evaluating the reinforcing efficiency of CNC on gelatin films. Specifically, we have employed the continuous casting as the processing method for obtaining the gelatin/CNC bionanocomposites. This required a first rheological study for assessing the effect of gelatin-CNC and CNC-CNC interactions on the colloidal state of the aqueous bionanocomposite formulations. CNC were isolated from eucalyptus pulp by sulfuric acid hydrolysis (65 wt%) at 55 °C for 30 min. Gelatin was solubilized in ultra-pure water at 85°C for 20 min and then mixed with glycerol at 20 wt.% and CNC at 0.5 wt%, 1.0 wt% and 2.5 wt%. Rotational measurements were performed to determine linear viscosity (η) of bionanocomposite solutions, which increased with increasing CNC content. At 2.5 wt% CNC, η increased by 118% regarding the neat gelatin solution, which was ascribed to percolation CNC network formation. Storage modulus (G’) and loss modulus (G″) further determined by oscillatory tests revealed that a gel-like behavior was dominant in the bionanocomposite solutions (G’ > G’’) over a broad range of temperature (20 – 85 °C), particularly at 2.5 wt% CNC. These results confirm effective interactions in the aqueous gelatin-CNC bionanocomposites that could substantially increase the physical properties of the gelatin plastics. Tensile tests are underway to confirm this hypothesis. The authors would like to thank the Fapesp (process n 2016/03080-3) for support.Keywords: bionanocomposites, cellulose nanocrystals, gelatin, viscoelastic characterization
Procedia PDF Downloads 1502846 Investigating Re-Use a Historical Masonry Arch Bridge
Authors: H. A. Erdogan
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Historical masonry arch bridges built centuries ago have fulfilled their function until recent decades. However, from the beginning of 20th century, these bridges have remained inadequate as a result of increasing speed, size and capacity of the means of transport. Although new bridges have been built in many places, masonry bridges located within the city limits still need to be used. When the size and transportation loads of modern vehicles are taken into account, it is apparent that historical masonry arch bridges would be exposed to greater loads than their initial design loads. Because of that, many precautions taken either remain insufficient or damage these bridges. In this study, the history of Debbaglar Bridge, one of the historic bridges located in the city center of Aksaray/Turkey is presented and its existing condition is evaluated. Structural analysis of the bridge under present conditions and loads is explained. Moreover, the retrofit and restoration application prepared considering the analysis data is described.Keywords: adaptive re-use, Aksaray debbaglar bridge, masonry bridge, reconstruction
Procedia PDF Downloads 3102845 A Comparison of Sulfur Mustard Cytotoxic Effects on the Two Human Lung Origin Cell Lines
Authors: P. Jost, L. Muckova, M. Matula, J. Pejchal, D. Jun, R. Stetina
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Sulfur mustard (bis(2-chlorethyl) sulfide) is highly toxic, chemical warfare agent that has been used in the past in several armed conflicts. Except for the skin, respiratory tract is one of the important routes of exposure. The elucidation and understanding of the mechanism of toxicity of SM have been effort intensive research. The multiple targets character of SM caused cellular damage resulted in activation of many different mechanisms which contribute to cellular response and participate in the final cytopathology effect. In our present work, we compared time-dependent changes in sulfur mustard exposed adult human lung fibroblasts NHLF and lung epithelial alveolar cell line A-549. Cell viability (MTT assay, Calcein-AM assay, and xCELLigence - real-time cell analysis), apoptosis (flow cytometry), mitochondrial membrane potential (Δψm, flow cytometry), reactive oxygen species induction (DC and cell cycle distribution (flow cytometry) were studied. We observed significantly decreased mitochondrial membrane potential and subsequent induction of apoptosis correlating with decreased cellular viability in the sulfur mustard exposed cells. In low concentrations, sulfur mustard-induced S-phase cell cycle arrest, on the other hand, high concentrations, cell cycle phase distribution of sulfur mustard exposed cells resembled cell cycle phase distribution of control group, which implies nonspecific cell cycle inhibition. Epithelial cells A-549 was found as more sensible to sulfur mustard toxicity. Acknowledgements: This work was supported by a long-term organization development plan Medical Aspects of Weapons of Mass Destruction of the Faculty of Military Health Sciences, University of Defence.Keywords: apoptosis, cell cycle, cytotoxicity, sulfur mustard
Procedia PDF Downloads 1922844 Direct Transient Stability Assessment of Stressed Power Systems
Authors: E. Popov, N. Yorino, Y. Zoka, Y. Sasaki, H. Sugihara
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This paper discusses the performance of critical trajectory method (CTrj) for power system transient stability analysis under various loading settings and heavy fault condition. The method obtains Controlling Unstable Equilibrium Point (CUEP) which is essential for estimation of power system stability margins. The CUEP is computed by applying the CTrjto the boundary controlling unstable equilibrium point (BCU) method. The Proposed method computes a trajectory on the stability boundary that starts from the exit point and reaches CUEP under certain assumptions. The robustness and effectiveness of the method are demonstrated via six power system models and five loading conditions. As benchmark is used conventional simulation method whereas the performance is compared with and BCU Shadowing method.Keywords: power system, transient stability, critical trajectory method, energy function method
Procedia PDF Downloads 3862843 Development of a Numerical Model to Predict Wear in Grouted Connections for Offshore Wind Turbine Generators
Authors: Paul Dallyn, Ashraf El-Hamalawi, Alessandro Palmeri, Bob Knight
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In order to better understand the long term implications of the grout wear failure mode in large-diameter plain-sided grouted connections, a numerical model has been developed and calibrated that can take advantage of existing operational plant data to predict the wear accumulation for the actual load conditions experienced over a given period, thus limiting the need for expensive monitoring systems. This model has been derived and calibrated based on site structural condition monitoring (SCM) data and supervisory control and data acquisition systems (SCADA) data for two operational wind turbine generator substructures afflicted with this challenge, along with experimentally derived wear rates.Keywords: grouted connection, numerical model, offshore structure, wear, wind energy
Procedia PDF Downloads 4532842 H∞ Takagi-Sugeno Fuzzy State-Derivative Feedback Control Design for Nonlinear Dynamic Systems
Authors: N. Kaewpraek, W. Assawinchaichote
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This paper considers an H∞ TS fuzzy state-derivative feedback controller for a class of nonlinear dynamical systems. A Takagi-Sugeno (TS) fuzzy model is used to approximate a class of nonlinear dynamical systems. Then, based on a linear matrix inequality (LMI) approach, we design an H∞ TS fuzzy state-derivative feedback control law which guarantees L2-gain of the mapping from the exogenous input noise to the regulated output to be less or equal to a prescribed value. We derive a sufficient condition such that the system with the fuzzy controller is asymptotically stable and H∞ performance is satisfied. Finally, we provide and simulate a numerical example is provided to illustrate the stability and the effectiveness of the proposed controller.Keywords: h-infinity fuzzy control, an LMI approach, Takagi-Sugano (TS) fuzzy system, the photovoltaic systems
Procedia PDF Downloads 3842841 Removal of Cr (VI) from Water through Adsorption Process Using GO/PVA as Nanosorbent
Authors: Syed Hadi Hasan, Devendra Kumar Singh, Viyaj Kumar
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Cr (VI) is a known toxic heavy metal and has been considered as a priority pollutant in water. The effluent of various industries including electroplating, anodizing baths, leather tanning, steel industries and chromium based catalyst are the major source of Cr (VI) contamination in the aquatic environment. Cr (VI) show high mobility in the environment and can easily penetrate cell membrane of the living tissues to exert noxious effects. The Cr (VI) contamination in drinking water causes various hazardous health effects to the human health such as cancer, skin and stomach irritation or ulceration, dermatitis, damage to liver, kidney circulation and nerve tissue damage. Herein, an attempt has been done to develop an efficient adsorbent for the removal of Cr (VI) from water. For this purpose nanosorbent composed of polyvinyl alcohol functionalized graphene oxide (GO/PVA) was prepared. Thus, obtained GO/PVA was characterized through FTIR, XRD, SEM, and Raman Spectroscopy. As prepared nanosorbent of GO/PVA was utilized for the removal Cr (VI) in batch mode experiment. The process variables such as contact time, initial Cr (VI) concentration, pH, and temperature were optimized. The maximum 99.8 % removal of Cr (VI) was achieved at initial Cr (VI) concentration 60 mg/L, pH 2, temperature 35 °C and equilibrium was achieved within 50 min. The two widely used isotherm models viz. Langmuir and Freundlich were analyzed using linear correlation coefficient (R2) and it was found that Langmuir model gives best fit with high value of R2 for the data of present adsorption system which indicate the monolayer adsorption of Cr (VI) on the GO/PVA. Kinetic studies were also conducted using pseudo-first order and pseudo-second order models and it was observed that chemosorptive pseudo-second order model described the kinetics of current adsorption system in better way with high value of correlation coefficient. Thermodynamic studies were also conducted and results showed that the adsorption was spontaneous and endothermic in nature.Keywords: adsorption, GO/PVA, isotherm, kinetics, nanosorbent, thermodynamics
Procedia PDF Downloads 3892840 Grading of Emulsified Agarwood Oil Using Gel Electrophoresis Technique
Authors: Y. T. Boon, M. N. Naim, R. Zakaria, N. F. Abu Bakar, N. Ahmad, I. W. Lenggoro
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In this study, encapsulation of agarwood oil with non-ionic surfactant, Tween 80 was prepared at critical micelle concentration of 0.0167 % v/v to produce the most stable nano-emulsion in aqueous. The encapsulation has minimized the bioactive compounds degradation in various pH conditions thus prolong their shelf life and maintained its initial oil grade. The oil grading of the prepared samples were conducted using the gel electrophoresis instead of using common analytical industrial grading such as gas chromatography- mass spectrometry (GC- MS). The grading method was chosen due to their unique zeta potential value after the encapsulation process. This paper demonstrates the feasibility of applying the electrophoresis principles to separate the encapsulated agarwood oil or grading of the emulsified agarwood oil. The results indicated that the grading process are potential to be further investigate based on their droplet size and zeta potential value at various pH condition when the droplet were migrate through polyacrylamide gel.Keywords: electrophoretic mobility, essential oil, nanoemulsion, polyacrylamide gel electrophoresis, tween 80, zeta potential
Procedia PDF Downloads 3802839 Characteristics and Challenges of Post-Burn Contractures in Adults and Children: A Descriptive Study
Authors: Hardisiswo Soedjana, Inne Caroline
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Deep dermal or full thickness burns are inevitably lead to post-burn contractures. These contractures remain to be one of the most concerning late complications of burn injuries. Surgical management includes releasing the contracture followed by resurfacing the defect accompanied by post-operative rehabilitation. Optimal treatment of post-burn contractures depends on the characteristics of the contractures. This study is aimed to describe clinical characteristics, problems, and management of post-burn contractures in adults and children. A retrospective analysis was conducted from medical records of patients suffered from contractures after burn injuries admitted to Hasan Sadikin general hospital between January 2016 and January 2018. A total of 50 patients with post burn contractures were included in the study. There were 17 adults and 33 children. Most patients were male, whose age range within 15-59 years old and 5-9 years old. Educational background was mostly senior high school among adults, while there was only one third of children who have entered school. Etiology of burns was predominantly flame in adults (82.3%); whereas flame and scald were the leading cause of burn injury in children (11%). Based on anatomical regions, hands were the most common affected both in adults (35.2%) and children (48.5%). Contractures were identified in 6-12 months since the initial burns. Most post-burn hand contractures were resurfaced with full-thickness skin graft (FTSG) both in adults and children. There were 11 patients who presented with recurrent contracture after previous history of contracture release. Post-operative rehabilitation was conducted for all patients; however, it is important to highlight that it is still challenging to control splinting and exercise when patients are discharged and especially the compliance in children. In order to improve quality of life in patients with history of deep burn injuries, prevention of contractures should begin right after acute care has been established. Education for the importance of splinting and exercise should be administered as comprehensible as possible for adult patients and parents of pediatric patients.Keywords: burn, contracture, education, exercise, splinting
Procedia PDF Downloads 1302838 Antibacterial Effects of Garcinia mangostana on Canine Superficial Pyoderma Pathogen, Staphylococcus pseudintermedius
Authors: Sineenat Kempubpha, Phornpa-Ngan Muadmuang, Putthamas Phetmuangprab, Surin Promphet, Sopita Bandit
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Introduction: Discarded pericarp of mangosteen (Garcinia mangostana) is a benefit to be developed as veterinary phytopharmacal products since it made up of abundance pharmacological active compounds. The active compounds of mangosteen pericarp not only act as an antihistamine, an anti-inflammatory, heart disease and HIV therapeutic substances but also act as antibacterial and antifungal agents. Aim: This study was an in vitro procedural attempt to determine the antibacterial effects of mangosteen pericarp 95% ethanol extract on the main causative pathogen of canine superficial pyoderma, Staphylococcus pseudintermedius. Methods: S. pseudintermedius were collected from various sites of the skin of canine superficial pyoderma dogs and were revived and lawn cultured. The S. pseudintermedius growth inhibition study was determined by disc diffusion technique, the mangosteen pericarp crude extracted was dissolved in 3 types of solvents (95% ethanol, 2% DMSO and distilled water, respectively). The micro broth dilution technique was used for determining both minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) values. Statistical analysis was done by calculating the mean of the zones of inhibition of tested microorganisms. Results: S. pseudintermedius growth inhibition study showed that the inhibition efficacy of 95% ethanol was greater than the inhibition efficacy of 2% DMSO and distilled water (9.10±0.18 mm, 6.95±0.60 mm and 6.80±0.18 mm, respectively). The MIC value was 125 µg/ml and the MBC value was 1 mg/ml. Conclusion: Mangosteen pericarp extract dissolved with 95% ethanol showed the highest zone of inhibition against the tested microorganisms. The MIC value was 125 µg/ml and the MBC value was 1 mg/ml which suggests its potent antibacterial action against S. pseudintermedius. However, further analytical studies are needed to isolate the key molecules of mangosteen pericarp for higher effect on canine superficial pyoderma microorganism therapeutic products.Keywords: mangosteen, Garcinia mangostana, Staphylococcus pseudintermedius, canine superficial pyoderma, in vitro study
Procedia PDF Downloads 2802837 Using Submerge Fermentation Method to Production of Extracellular Lipase by Aspergillus niger
Authors: Masoumeh Ghasemi, Afshin Farahbakhsh, Arman Farahbakhsh, Ali Asghar Safari
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In this study, lipase production has been investigated using submerge fermentation by Aspergillus niger in Kilka fish oil as main substrate. The Taguchi method with an L9 orthogonal array design was used to investigate the effect of parameters and their levels on lipase productivity. The optimum conditions for Kilka fish oil concentration, incubation temperature and pH were obtained 3 gr./ml 35°C and 7, respectively. The amount of lipase activity in optimum condition was obtained 4.59IU/ml. By comparing this amount with the amount of productivity in the olive oil medium based on the cost of each medium, it was that using Kilka fish oil is 84% economical. Therefore Kilka fish oil can be used as an economical and suitable substrate in the lipase production and industrial usages.Keywords: lipase, Aspergillus niger, Kilka fish oil, submerge fermentation method
Procedia PDF Downloads 4472836 Association of Glutathione S-transferase M1 and T1 Gene Polymorphisms with Vitiligo in Saudi Population
Authors: Ghaleb Bin Huraib, Fahad Al Harthi, Mohammad Mustafa, Abdulrahman Al-Asmari
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Introduction: Vitiligo is an acquired pigmentary skin disorder with the regional disappearance of melanocytes. Vitiligo affects 0.1 to 2% of the global population, and the incidence varies substantially depending on ethnicity. Glutathione S-transferase (GST) is a multigene family of enzymes that detoxify oxidative stress products. The oxidative stress-related GSTM1/GSTT1 genes deletion may cause epidermal melanocytes destruction and the development of vitiligo. Hence, the present study aimed to investigate the association of GST gene polymorphisms with vitiligo in the Saudi population, if any. Materials and Methods: The present study includes 129 vitiligo cases and 130 age-matched healthy controls. The proportion of male and female patients with vitiligo is almost equal. The multiplex polymerase chain reaction (PCR) method was used for polymorphic analysis. Results: Increased odds of generalized vitiligo was observed with the null genotypes of GSTT1- gene (OR = 1.91, 95% CI = 1.07-3.42, p = 0.019). The possible genetic combinations of GSTM1/GSTT1 and their genotypic distribution showed the frequency of GSTM1+/GSTT1+ 62/130 (47.69%) and GSTM1-/GSTT1+ 52/130 (40.00%) were higher in controls than in cases 44/129 (34.11%), 43/129 (33.34%), respectively while GSTM1+/GSTT1- and GSTM1-/GSTT1- null genotypes were higher 22/129 (17.05%) and 20/129 (15.50%) in vitiligo patients as compared to controls 11/130 (8.46%), 5/130 (3.84%), respectively. The strength of association of different genetic combinations with cases have shown GSTM1+/GSTT1- (OR = 2.81, 95% CI = 1.24-6.40, p = 0.009) and GSTM1-/GSTT1- (OR = 5.63, 95% CI = 1.96 - 16.16, p = 0.0004) were significantly higher in vitiligo cases as compared to controls. We did not observe any significant association of age and gender of patients with GST gene polymorphisms. Conclusions: The GSTT1-, GSTM1+/GSTT1- and GSTM1-/GSTT1- null genotypes were significantly associated with vitiligo. These genetic polymorphisms may be the associative genetic risk factor for vitiligo among Saudis. It could be used as a genetic marker for screening vitiligo patients among Saudis. Further studies on GSTs gene polymorphism in larger sample sizes from different geographical areas and ethnicity are needed to strengthen the present findings.Keywords: vitiligo, GSTM1, GSTT1, gene polymorphism, oxidative stress
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