Search results for: heart failure rehospitalization
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 3377

Search results for: heart failure rehospitalization

1457 Accelerated Evaluation of Structural Reliability under Tsunami Loading

Authors: Sai Hung Cheung, Zhe Shao

Abstract:

It is of our great interest to quantify the risk to structural dynamic systems due to earthquake-induced tsunamis in view of recent earthquake-induced tsunamis in Padang, 2004 and Tohoku, 2011 which brought huge losses of lives and properties. Despite continuous advancement in computational simulation of the tsunami and wave-structure interaction modeling, it still remains computationally challenging to evaluate the reliability of a structural dynamic system when uncertainties related to the system and its modeling are taken into account. The failure of the structure in a tsunami-wave-structural system is defined as any response quantities of the system exceeding specified thresholds during the time when the structure is subjected to dynamic wave impact due to earthquake-induced tsunamis. In this paper, an approach based on a novel integration of a recently proposed moving least squares response surface approach for stochastic sampling and the Subset Simulation algorithm is proposed. The effectiveness of the proposed approach is discussed by comparing its results with those obtained from the Subset Simulation algorithm without using the response surface approach.

Keywords: response surface, stochastic simulation, structural reliability tsunami, risk

Procedia PDF Downloads 676
1456 Study of Bolt Inclination in a Composite Single Bolted Joint

Authors: Faci Youcef, Ahmed Mebtouche, Djillali Allou, Maalem Badredine

Abstract:

The inclination of the bolt in a fastened joint of composite material during a tensile test can be influenced by several parameters, including material properties, bolt diameter and length, the type of composite material being used, the size and dimensions of the bolt, bolt preload, surface preparation, the design and configuration of the joint, and finally testing conditions. These parameters should be carefully considered and controlled to ensure accurate and reliable results during tensile testing of composite materials with fastened joints. Our work focuses on the effect of the stacking sequence and the geometry of specimens. An experimental test is carried out to obtain the inclination of a bolt during a tensile test of a composite material using acoustic emission and digital image correlation. Several types of damage were obtained during the load. Digital image correlation techniques permit the obtaining of the inclination of bolt angle value during tensile test. We concluded that the inclination of the bolt during a tensile test of a composite material can be related to the damage that occurs in the material. It can cause stress concentrations and localized deformation in the material, leading to damage such as delamination, fiber breakage, matrix cracking, and other forms of failure.

Keywords: damage, inclination, analyzed, carbon

Procedia PDF Downloads 57
1455 Lifetime Assessment of Highly Efficient Metal-Based Air-Diffuser through Accelerated Degradation Test

Authors: Jinyoung Choi, Tae-Ho Yoon, Sunmook Lee

Abstract:

Degradation of standard oxygen transfer efficiency (SOTE) with time was observed for the assessment of lifetime of metal-based air-diffuser, which displaced a polymer composite-based air-diffuser in order to attain a longer lifetime in the actual field. The degradation of air-diffuser occurred due to the failure of the formation of small and uniform air bubbles since the patterns formed on the disc of air-diffuser deteriorated and/or changed from their initial shapes while they were continuously exposed to the air blowing condition during the operation in the field. Therefore, the lifetime assessment of metal-based air-diffuser was carried out through an accelerated degradation test by accelerating the air-blowing conditions in 200 L/min, 300 L/min, and 400 L/min and the lifetime of normal operating condition at 120 L/min was predicted. It was found that Weibull distribution was the most proper one for describing the lifetime distribution of metal-based air-diffuser in the present study. The shape and scale parameters indicated that the accelerated blowing conditions were all within the acceleration domain. The lifetime was predicted by adopting inverse power model for a stress-life relationship and estimated to be B10=94,004 hrs with CL=95%. Acknowledgement: This work was financially supported by the Ministry of Trade, Industry and Energy (Grant number: N0001475).

Keywords: accelerated degradation test, air-diffuser, lifetime assessment, SOTE

Procedia PDF Downloads 562
1454 Adoption of Digital Storytelling Tool to Teach 21st Century Skills by Malaysian Pre-service Teachers

Authors: Siti Aisyah binti Jumpaan

Abstract:

21ˢᵗ century skills (PAK-21) integration has made its way into Malaysian curriculum when Ministry of Education introduce its implementation since 2016. This study was conducted to explore pre-service teachers’ readiness in integrating 21st century skills in the classroom via the digital storytelling (DST) method and to find gaps between theory and practice that can be integral towards pre-service teachers’ professional growth. Qualitative research method was used in this research involving six respondents who were selected using a purposive sampling method. Their response from interviews and lesson plan analysis were analysed using narrative analysis. The findings showed that pre-service teachers showed a moderate level of readiness in integrating 21st century skills using DST. Pre-service teachers demonstrated high level of preparedness in writing their lesson plan, but their interview revealed that they faced struggles in implementation due to several factors, such as lack of technology and failure to obtain students’ participation. This study further strengthens the need for specialised curriculum for pre-service teachers in teaching 21st century skills via DST.

Keywords: digital storytelling, 21ˢᵗ century skills, preservice teachers, teacher training

Procedia PDF Downloads 92
1453 Bioelectronic System for Continuous Monitoring of Cardiac Activity of Benthic Invertebrates for the Assessment of a Surface Water Quality

Authors: Sergey Kholodkevich, Tatiana Kuznetsova

Abstract:

The objective assessment of ecological state of water ecosystems is impossible without the use of biological methods of the environmental monitoring capable in the integrated look to reveal negative for biota changes of quality of water as habitats. Considerable interest for the development of such methods of environmental quality control represents biomarker approach. Measuring systems, by means of which register cardiac activity characteristics, received the name of bioelectronic. Bioelectronic systems are information and measuring systems in which animals (namely, benthic invertebrates) are directly included in structure of primary converters, being an integral part of electronic system of registration of these or those physiological or behavioural biomarkers. As physiological biomarkers various characteristics of cardiac activity of selected invertebrates have been used in bioelectronic system.lChanges in cardiac activity are considered as integrative measures of the physiological condition of organisms, which reflect the state of the environment of their dwelling. Greatest successes in the development of tools of biological methods and technologies of an assessment of surface water quality in real time. Essential advantage of bioindication of water quality by such tool is a possibility of an integrated assessment of biological effects of pollution on biota and also the expressness of such method and used approaches. In the report the practical experience of authors in biomonitoring and bioindication of an ecological condition of sea, brackish- and freshwater areas is discussed. Authors note that the method of non-invasive cardiac activity monitoring of selected invertebrates can be used not only for the advancement of biomonitoring, but also is useful in decision of general problems of comparative physiology of the invertebrates.

Keywords: benthic invertebrates, physiological state, heart rate monitoring, water quality assessment

Procedia PDF Downloads 717
1452 Role of Human Wharton’s Jelly Mesenchymal Stem Cells Conditioned Media in Alleviating Kidney Injury via Inhibition of Renin-Angiotensin System in Diabetic Nephropathy

Authors: Pardis Abolghasemi, Benyamin Hatamsaz

Abstract:

Background: Diabetic nephropathy is a serious health problem described by specific kidney structure and functional disturbance. Renoprotective effects of the stem cells secretase have been shown in many kidney diseases. The aim is to evaluate the capability of human Wharton’s jelly mesenchymal stem cells conditioned media (hWJMSCs-CM) to alleviate DN in streptozotocin (STZ)-induced diabetes. Methods: Diabetic nephropathy was induced by injection of STZ (60 mg/kg, IP) in twenty rats. Conditioned media was extracted from hWJMSCs at third passages. At week 8, diabetic rats were divided into two groups: treated (hWJMSCs-CM, 500 μl/rat for three weeks, IP) and not treated (DN). In the 11th week, three groups (control, DN and DN+hWJMSCs-CM) were kept in metabolic cages and urine was collected for 24h. Blood pressure (BP) and heart rate (HR) were continuously recorded. The serum samples were maintained for measuring BUN, Cr and angiotensin-converting enzyme (ACE) activity. The left kidney was kept at -80°C for ACE activity assessment. The right kidney and pancreas were used for histopathologic evaluation. Result: Diabetic nephropathy was detected by microalbuminuria and increased albumin/creatinine ratio, as well as the pancreas and renal structural disturbance. Glomerular filtration rate, BP and HR increased in the DN group. The ACE activity was elevated in the serum and kidneys of the DN group. Administration of hWJMSCs-CM modulated the renal functional and structural disturbance and decreased the ACE activity. Conclusion: Conditioned media was extracted from hWJMSCs may have a Renoprotective effect in diabetic nephropathy. This may happen through regulation of ACE activity and renin-angiotensin system inhibition.

Keywords: diabetic nephropathy, mesenchymal stem cells, immunomodulation, anti-inflammation

Procedia PDF Downloads 203
1451 Template Design Packages for Repetitive Construction Projects

Authors: Ali Youniss Aidbaiss, G. Unnikrishnan, Anoob Hakim

Abstract:

Scope changes, scope creeps, cost and time overruns have become common in projects in the oil and gas sector. Even in repetitive projects, failure to implement lessons learnt and correct past mistakes have resulted in various setbacks. This paper describes the concept of reusing successfully implemented design packages as templates for repetitive projects, and thereby lowering the instances of project failures. Units or systems successfully installed in projects can be identified and taken up for preparing template design packages. Standardization of units and systems helps to develop templates from successful designs which can be repeatedly used with confidence. These packages can be used with minimum modifications for developing FEED packages faster, saving cost and other valuable resources. Lessons learnt from the completed project incorporated in the templates avoid repeating past mistakes during detailed design, procurement and execution. With template packages, consistent quality can be maintained for similar projects, avoiding scope creep and scope changes which will ultimately result in cost and time savings.

Keywords: engineering work package, repetitive construction, template design package, time saving in projects

Procedia PDF Downloads 318
1450 Effects of Repeated High Loadings on the Performance of Adhesively-Bonded Single Lap Joints

Authors: Orkun Yavuz, Ferhat Kadioğlu, M. Emin Ercan

Abstract:

This study aims to investigate the effects of repeated high loadings on the performance of adhesively-bonded Single Lap Joints (SLJs) by employing both experimental and numerical approaches. A projectile with a mass of 1.25 gr and density of 11.3 gr/cm3 was fired at the joints with a velocity of about 280 m/s using a specially designed experimental set-up, and the impact was recorded via a high-speed camera. The SLJs were manufactured from 6061 aluminum adherend (AA6061) material and an adhesive film. The joints, which have an adherend thickness of 4 mm and overlap length of 15 mm, were subjected to up to 3 shots for the ballistic test, followed by quasi-static tensile testing. The impacted joints, then, were compared to the non-impacted and one-shot impacted ones, which was a subject of investigation carried out before. It was found that while the joints subjected to 2 shots mechanically deteriorated, those subjected to 3 shots experienced a complete failure at the end of the experiment. A numerical study was also conducted using an ABAQUS package program. While the adherends were modelled using the Johnson-Cook deformation parameters, an elastoplastic behavior of the adhesive was used as input data in the analyses. It seems the experimental results confirm the numerical ones.

Keywords: ballistic tests, adhesive joints, numerical analysis, SLJ

Procedia PDF Downloads 64
1449 An Experimental Investigation on Mechanical Behaviour of Fiber Reinforced Polymer (FRP) Composite Laminates Used for Pipe Applications

Authors: Tasnim Kallel, Rim Taktak

Abstract:

In this experimental work, fiber reinforced polymer (FRP) composite laminates were manufactured using hand lay-up technique. The unsaturated polyester (UP) and vinylester (VE) were considered as resins reinforced with different woven fabrics (bidirectional and quadriaxial rovings). The mechanical behaviour of the resulting composites was studied and then compared. A focus was essentially done on the evaluation of the effect of E-Glass fiber and ply orientation on the mechanical properties such as tensile strength, flexural strength, and hardness of the studied composite laminates. Also, crack paths and fracture surfaces were examined, and failure mechanisms were analyzed. From the main results, it was found that the quadriaxial composite laminates (QA/VE and QA/UP) with stacking sequences of [0°, +45°, 90°, -45°] present a very ductile tensile behaviour. The other laminate samples (R500/VE, RM/VE, R500/UP and RM/UP) show a very brittle behaviour whatever the used resin. The intrinsic toughness KIC of QA/VE laminate, obtained in fracture tests, are found more important than that of RM/VE composite. Thus, the QA/VE samples, as multidirectional laminate, presents the highest interlaminar fracture resistance.

Keywords: crack growth, fiber orientation, fracture behavior, e-glass fiber fabric, laminate composite, mechanical behavior

Procedia PDF Downloads 250
1448 Geotechnical Characterization of Landslide in Dounia Park, Algiers, Algeria

Authors: Mira Filali, Amar Nechnech

Abstract:

Most landslides in Algiers take place in Piacenzian marls of the Sahel (port in Arabic) and cause severe damage to properties and infrastructures. The aim of this paper is to describe the results of experimental as well as theoretical analysis of landslides. In order to understand the process which caused this slope instabilities, the results of geotechnical investigation carried out by the laboratory of construction (LNHC) laboratory in the area of Dounia park were analyzed, including particle size distribution, Atterberg limits, shear strength, odometer and pressuremeter tests. The study shows that the soils exhibited a high capacity to swelling according to index plasticity and clay content. Highs limit liquidity (LL) (53.45%) means that the soils are susceptible to landslides. The stability analysis carried out using finite element method, shows that the slope is stable (Fs > 1) in dry condition and in static state. Despite this results, the stable site could be described as only conditionally stable because slope failure can occur under combined effect of different factors. In fact the safety factor obtained by applying load when the phreatic surface is at ground, less than 1.5.

Keywords: index properties, landslides, safety factor, slope stability

Procedia PDF Downloads 239
1447 The Role of Business Incubation Centers (BICS) in Fostering Entrepreneurship in Pakistani Universities

Authors: Shah Hussain Awan

Abstract:

This study investigates the role of Business Incubation Centers (BICs) in fostering entrepreneurship in Pakistani universities. The high failure rate in new startups around the world has opened a challenging discussion. Though encouraging steps and strategies have been taken to overcome these challenges, still more aggressive action needs to be taken. However, Pakistan is one of the countries that promote entrepreneurship through BICs. The purpose of the present study is to develop a conceptual model that assesses the moderating impact of government policy on entrepreneurship development through business incubation centers of public and private universities. This area is under-researched, particularly in the context of Pakistan; therefore, this research may contribute to the existing body of knowledge to appraise the industry in Pakistan. The data collection procedure included a survey of stakeholders from private and public universities in Pakistan and was analyzed by SmartPLS 4.0. The findings show that Business incubation centers and government support have a significant impact on entrepreneurship development in Pakistan. Moderation analysis showed that for business incubation centers to be successful and effective, the government needs to implement efficient policies to inculcate entrepreneurship.

Keywords: business incubation centers, government support, policies, startup performance, entrepreneurship development

Procedia PDF Downloads 52
1446 Evaluation of Polymerisation Shrinkage of Randomly Oriented Micro-Sized Fibre Reinforced Dental Composites Using Fibre-Bragg Grating Sensors and Their Correlation with Degree of Conversion

Authors: Sonam Behl, Raju, Ginu Rajan, Paul Farrar, B. Gangadhara Prusty

Abstract:

Reinforcing dental composites with micro-sized fibres can significantly improve the physio-mechanical properties of dental composites. The short fibres can be oriented randomly within dental composites, thus providing quasi-isotropic reinforcing efficiency unlike unidirectional/bidirectional fibre reinforced composites enhancing anisotropic properties. Thus, short fibres reinforced dental composites are getting popular among practitioners. However, despite their popularity, resin-based dental composites are prone to failure on account of shrinkage during photo polymerisation. The shrinkage in the structure may lead to marginal gap formation, causing secondary caries, thus ultimately inducing failure of the restoration. The traditional methods to evaluate polymerisation shrinkage using strain gauges, density-based measurements, dilatometer, or bonded-disk focuses on average value of volumetric shrinkage. Moreover, the results obtained from traditional methods are sensitive to the specimen geometry. The present research aims to evaluate the real-time shrinkage strain at selected locations in the material with the help of optical fibre Bragg grating (FBG) sensors. Due to the miniature size (diameter 250 µm) of FBG sensors, they can be easily embedded into small samples of dental composites. Furthermore, an FBG array into the system can map the real-time shrinkage strain at different regions of the composite. The evaluation of real-time monitoring of shrinkage values may help to optimise the physio-mechanical properties of composites. Previously, FBG sensors have been able to rightfully measure polymerisation strains of anisotropic (unidirectional or bidirectional) reinforced dental composites. However, very limited study exists to establish the validity of FBG based sensors to evaluate volumetric shrinkage for randomly oriented fibres reinforced composites. The present study aims to fill this research gap and is focussed on establishing the usage of FBG based sensors for evaluating the shrinkage of dental composites reinforced with randomly oriented fibres. Three groups of specimens were prepared by mixing the resin (80% UDMA/20% TEGDMA) with 55% of silane treated BaAlSiO₂ particulate fillers or by adding 5% of micro-sized fibres of diameter 5 µm, and length 250/350 µm along with 50% of silane treated BaAlSiO₂ particulate fillers into the resin. For measurement of polymerisation shrinkage strain, an array of three fibre Bragg grating sensors was embedded at a depth of 1 mm into a circular Teflon mould of diameter 15 mm and depth 2 mm. The results obtained are compared with the traditional method for evaluation of the volumetric shrinkage using density-based measurements. Degree of conversion was measured using FTIR spectroscopy (Spotlight 400 FT-IR from PerkinElmer). It is expected that the average polymerisation shrinkage strain values for dental composites reinforced with micro-sized fibres can directly correlate with the measured degree of conversion values, implying that more C=C double bond conversion to C-C single bond values also leads to higher shrinkage strain within the composite. Moreover, it could be established the photonics approach could help assess the shrinkage at any point of interest in the material, suggesting that fibre-Bragg grating sensors are a suitable means for measuring real-time polymerisation shrinkage strain for randomly fibre reinforced dental composites as well.

Keywords: dental composite, glass fibre, polymerisation shrinkage strain, fibre-Bragg grating sensors

Procedia PDF Downloads 154
1445 Seismic Behavior of Three-Dimensional Steel Buildings with Post-Tensioned Connections

Authors: Manuel E. Soto-López, Israel Gaxiola-Avendaño, Alfredo Reyes-Salazar, Eden Bojórquez, Sonia E. Ruiz

Abstract:

The seismic responses of steel buildings with semi-rigid post-tensioned connections (PC) are estimated and compared with those of steel buildings with typical rigid (welded) connections (RC). The comparison is made in terms of global and local response parameters. The results indicate that the seismic responses in terms of interstory shears, roof displacements, axial load and bending moments are smaller for the buildings with PC connection. The difference is larger for global than for local parameters, which in turn varies from one column location to another. The reason for this improved behavior is that the buildings with PC dissipate more hysteretic energy than those with RC. In addition, unlike the case of buildings with WC, for the PC structures the hysteretic energy is mostly dissipated at the connections, which implies that structural damage in beams and columns is not significant. According to this results, steel buildings with PC are a viable option in highseismicity areas because of their smaller response and self-centering connection capacity as well as the fact that brittle failure is avoided.

Keywords: inter-story drift, nonlinear time-history analysis, post-tensioned connections, steel buildings

Procedia PDF Downloads 499
1444 Case Studies of Mitigation Methods against the Impacts of High Water Levels in the Great Lakes

Authors: Jennifer M. Penton

Abstract:

Record high lake levels in 2017 and 2019 (2017 max lake level = 75.81 m; 2018 max lake level = 75.26 m; 2019 max lake level = 75.92 m) combined with a number of severe storms in the Great Lakes region, have resulted in significant wave generation across Lake Ontario. The resulting large wave heights have led to erosion of the natural shoreline, overtopping of existing revetments, backshore erosion, and partial and complete failure of several coastal structures, which in turn have led to further erosion of the shoreline and damaged existing infrastructure. Such impacts can be seen all along the coast of Lake Ontario. Three specific locations have been chosen as case studies for this paper, each addressing erosion and/or flood mitigation methods, such as revetments and sheet piling with increased land levels. Varying site conditions and the resulting shoreline damage are compared herein. The results are reflected in the case-specific design components of the mitigation and adaptation methods and are presented in this paper.

Keywords: erosion mitigation, flood mitigation, great lakes, high water levels

Procedia PDF Downloads 173
1443 Bus Transit Demand Modeling and Fare Structure Analysis of Kabul City

Authors: Ramin Mirzada, Takuya Maruyama

Abstract:

Kabul is the heart of political, commercial, cultural, educational and social life in Afghanistan and the fifth fastest growing city in the world. Minimum income inclined most of Kabul residents to use public transport, especially buses, although there is no proper bus system, beside that there is no proper fare exist in Kabul city Due to wars. From 1992 to 2001 during civil wars, Kabul suffered damage and destruction of its transportation facilities including pavements, sidewalks, traffic circles, drainage systems, traffic signs and signals, trolleybuses and almost all of the public transport system (e.g. Millie bus). This research is mainly focused on Kabul city’s transportation system. In this research, the data used have been gathered by Japan International Cooperation Agency (JICA) in 2008 and this data will be used to find demand and fare structure, additionally a survey was done in 2016 to find satisfaction level of Kabul residents for fare structure. Aim of this research is to observe the demand for Large Buses, compare to the actual supply from the government, analyze the current fare structure and compare it with the proposed fare (distance based fare) structure which has already been analyzed. Outcome of this research shows that the demand of Kabul city residents for the public transport (Large Buses) exceeds from the current supply, so that current public transportation (Large Buses) is not sufficient to serve public transport in Kabul city, worth to be mentioned, that in order to overcome this problem, there is no need to build new roads or exclusive way for buses. This research proposes government to change the fare from fixed fare to distance based fare, invest on public transportation and increase the number of large buses so that the current demand for public transport is met.

Keywords: transportation, planning, public transport, large buses, Kabul, Afghanistan

Procedia PDF Downloads 314
1442 Effect of Equal Channel Angular Pressing Process on Impact Property of Pure Copper

Authors: Fahad Al-Mufadi, F. Djavanroodi

Abstract:

Ultrafine grained (UFG) and nanostructured (NS) materials have experienced a rapid development during the last decade and made profound impact on every field of materials science and engineering. The present work has been undertaken to develop ultra-fine grained pure copper by severe plastic deformation method and to examine the impact property by different characterizing tools. For this aim, equal channel angular pressing die with the channel angle, outer corner angle and channel diameter of 90°, 17° and 20 mm had been designed and manufactured. Commercial pure copper billets were ECAPed up to four passes by route BC at the ambient temperature. The results indicated that there is a great improvement at the hardness measurement, yield strength and ultimate tensile strength after ECAP process. It is found that the magnitudes of HV reach 136HV from 52HV after the final pass. Also, about 285% and 125% enhancement at the YS and UTS values have been obtained after the fourth pass as compared to the as-received conditions, respectively. On the other hand, the elongation to failure and impact energy have been reduced by imposing ECAP process and pass numbers. It is needed to say that about 56% reduction in the impact energy have been attained for the samples as contrasted to annealed specimens.

Keywords: SPD, ECAP, pure cu, impact property

Procedia PDF Downloads 259
1441 Jurisprudencial Analysis of Torture in Spain and in the European Human Rights System

Authors: María José Benítez Jiménez

Abstract:

Article 3 of the European Convention for the Protection of Human Rights and Fundamental Freedoms (E.C.H.R.) proclaims that no one may be subjected to torture, punishment or degrading treatment. The legislative correlate in Spain is embodied in Article 15 of the Spanish Constitution, and there must be an overlapping interpretation of both precepts on the ideal plane. While it is true that there are not many cases in which the European Court of Human Rights (E.C.t.H.R. (The Strasbourg Court)) has sanctioned Spain for its failure to investigate complaints of torture, it must be emphasized that the tendency to violate Article 3 of the Convention appears to be on the rise, being necessary to know possible factors that may be affecting it. This paper addresses the analysis of sentences that directly or indirectly reveal the violation of Article 3 of the European Convention. To carry out the analysis, sentences of the Strasbourg Court have been consulted from 2012 to 2016, being able to address any previous sentences to this period if it provided justified information necessary for the study. After the review it becomes clear that there are two key groups of subjects that request a response to the Strasbourg Court on the understanding that they have been tortured or degradingly treated. These are: immigrants and terrorists. Both phenomena, immigration and terrorism, respond to patterns that have mutated in recent years, and it is important for this study to know if national regulations begin to be dysfunctional.

Keywords: E.C.H.R., E.C.t.H.R. sentences, Spanish Constitution, torture

Procedia PDF Downloads 160
1440 Assessment of Cardioprotective Effect of Deferiprone on Doxorubicin-Induced Cardiac Toxicity in a Rat Model

Authors: Sadaf Kalhori

Abstract:

Introduction: Doxorubicin (DOX)-induced cardiotoxicity is widely known as the most severe complication of anthracycline-based chemotherapy in patients with cancer. It is unknown whether Deferiprone (DFP), could reduce the severity of DOX-induced cardiotoxicity by inhibiting free radical reactions. Thus, this study was performed to assess the protective effect of Deferiprone on DOX-induced cardiotoxicity in a rat model. Methods: The rats were divided into five groups. Group one was a control group. Group 2 was DOX (2 mg/kg/day, every other day for 12 days), and Group three to five which receiving DOX as in group 2 and DFP 75,100 and 150 mg/kg/day, for 19 days, respectively. DFP was starting 5 days prior to the first DOX injection and two days after the last DOX injection throughout the study. Electrocardiographic and hemodynamic studies, along with histopathological examination, were conducted. In addition, serum sample was taken and total cholesterol, Malone dialdehyde, triglyceride, albumin, AST, ALT, total protein, lactate dehydrogenase, total anti-oxidant and creatine kinase were assessed. Result: Our results showed the normal structure of endocardial, myocardial and pericardial in the control group. Pathologic data such as edema, hyperemia, bleeding, endocarditis, myocarditis and pericarditis, hyaline degeneration, cardiomyocyte necrosis, myofilament degeneration and nuclear chromatin changes were assessed in all groups. In the DOX group, all pathologic data was seen with mean grade of 2±1.25. In the DFP group with a dose of 75 and 100 mg, the mean grade was 1.41± 0.31 and 1±.23, respectively. In DFP group with a dose of 150, the pathologic data showed a milder change in comparison with other groups with e mean grade of 0.45 ±0.19. Most pathologic data in DFP groups showed significant changes in comparison with the DOX group (p < 0.001). Discussion: The results also showed that DFP treatment significantly improved DOX-induced heart damage, structural changes in the myocardium, and ventricular function. Our data confirm that DFP is protective against cardiovascular-related disorders induced by DOX. Clinical studies are needed to be involved to examine these findings in humans.

Keywords: cardiomyopathy, deferiprone, doxorubicin, rat

Procedia PDF Downloads 142
1439 Computer-Aided Diagnosis of Polycystic Kidney Disease Using ANN

Authors: G. Anjan Babu, G. Sumana, M. Rajasekhar

Abstract:

Many inherited diseases and non-hereditary disorders are common in the development of renal cystic diseases. Polycystic kidney disease (PKD) is a disorder developed within the kidneys in which grouping of cysts filled with water like fluid. PKD is responsible for 5-10% of end-stage renal failure treated by dialysis or transplantation. New experimental models, application of molecular biology techniques have provided new insights into the pathogenesis of PKD. Researchers are showing keen interest for developing an automated system by applying computer aided techniques for the diagnosis of diseases. In this paper a multi-layered feed forward neural network with one hidden layer is constructed, trained and tested by applying back propagation learning rule for the diagnosis of PKD based on physical symptoms and test results of urinanalysis collected from the individual patients. The data collected from 50 patients are used to train and test the network. Among these samples, 75% of the data used for training and remaining 25% of the data are used for testing purpose. Furthermore, this trained network is used to implement for new samples. The output results in normality and abnormality of the patient.

Keywords: dialysis, hereditary, transplantation, polycystic, pathogenesis

Procedia PDF Downloads 380
1438 Numerical Study on the Ultimate Load of Offshore Two-Planar Tubular KK-Joints at Fire-Induced Elevated Temperatures

Authors: Hamid Ahmadi, Neda Azari-Dodaran

Abstract:

A total of 270 nonlinear steady-state finite element (FE) analyses were performed on 54 FE models of two-planar circular hollow section (CHS) KK-joints subjected to axial loading at five different temperatures (20 ºC, 200 ºC, 400 ºC, 550 ºC, and 700 ºC). The primary goal was to investigate the effects of temperature and geometrical characteristics on the ultimate strength, modes of failure, and initial stiffness of the KK-joints. Results indicated that on an average basis, the ultimate load of a two-planar tubular KK-joint at 200 ºC, 400 ºC, 550 ºC, and 700 ºC is 90%, 75%, 45%, and 16% of the joint’s ultimate load at ambient temperature, respectively. Outcomes of the parametric study showed that replacing the yield stress at ambient temperature with the corresponding value at elevated temperature to apply the EN 1993-1-8 equations for the calculation of the joint’s ultimate load at elevated temperatures may lead to highly unconservative results that might endanger the safety of the structure. Results of the parametric study were then used to develop a set of design formulas, through nonlinear regression analyses, to calculate the ultimate load of two-planar tubular KK-joints subjected to axial loading at elevated temperatures.

Keywords: ultimate load, two-planar tubular KK-joint, axial loading, elevated temperature, parametric equation

Procedia PDF Downloads 158
1437 Investment Guide in Qatar

Authors: Mohamad Farhad Bakhtiyariyan

Abstract:

One of the manner to earning profit and having a high income, is investing in an acceptable market. Every the thinker brain knows, investing in the business world today, maybe, have a manifold profit or lead to failure. So, before entering in the investment market, we must have a comprehensive and sufficient awareness, know markets, acquainted with the main industrial activities, know the rules and regulation and consider the conditions of society. Qatar, as a one of the richest countries in the world, can be a good destination for investment. The inflation rate, taxes, easiness of the importing, company registration, ease of exporting process, profitable and appropriate markets, simple and applicable rules, all of this has made Qatar, one of the best and gainful investment countries. Above all, Qatar 2022 world cup event, has led of investment in this country efficiently and profitable method. In this paper, first, we have introduced the Qatar and its location, also looked at the countries international markets during the world cup and we have described the impact of the world cup on business, and then the laws and regulations of the Qatar in the field of investment, company registration, ownership by foreigners, obtaining residency by investors, export and import process in second part its examined, and in third part, major investment markets, principal industrial activities in Qatar, markets affected by the world cup and the main needs of this country in various fields during the world cup, have been investigated.

Keywords: investment, Qatar, markets, world cup

Procedia PDF Downloads 194
1436 Physical and Mechanical Characterization of Limestone in the Quarry of Meftah (Algeria)

Authors: Khaled Benyounes

Abstract:

Determination of the rock mechanical properties such as unconfined compressive strength UCS, Young’s modulus E, and tensile strength by the Brazilian test Rtb is considered to be the most important component in drilling and mining engineering project. Research related to establishing correlation between strength and physical parameters of rocks has always been of interest to mining and reservoir engineering. For this, many rock blocks of limestone were collected from the quarry located in Meftah (Algeria), the cores were crafted in the laboratory using a core drill. This work examines the relationships between mechanical properties and some physical properties of limestone. Many empirical equations are established between UCS and physical properties of limestone (such as dry bulk density, velocity of P-waves, dynamic Young’s modulus, alteration index, and total porosity). Other correlations, UCS - tensile strength, dynamic Young’s modulus - static Young’s modulus have been find. Based on the Mohr-Coulomb failure criterion, we were able to establish mathematical relationships that will allow estimating the cohesion and internal friction angle from UCS and indirect tensile strength. Results from this study can be useful for mining industry for resolve range of geomechanical problems such as slope stability.

Keywords: limestone, mechanical strength, Young’s modulus, porosity

Procedia PDF Downloads 637
1435 Study of Effect of Gear Tooth Accuracy on Transmission Mount Vibration

Authors: Kalyan Deepak Kolla, Ketan Paua, Rajkumar Bhagate

Abstract:

Transmission dynamics occupy major role in customer perception of the product in both senses of touch and quality of sound. The quantity and quality of sound perceived is more concerned with the whine noise of the gears engaged. Whine noise is tonal in nature and tonal noises cause fatigue and irritation to customers, which in turn affect the quality of the product. Transmission error is the usual suspect for whine noise, which can be caused due to misalignments, tolerances, manufacturing variabilities. In-cabin noise is also more sensitive to the gear design. As the details of the gear tooth design and manufacturing are in microns, anything out of the tolerance zone, either in design or manufacturing, will cause a whine noise. This will also cause high variation in stress and deformation due to change in the load and leads to the fatigue failure of the gears. Hence gear design and development take priority in the transmission development process. This paper aims to study such variability by considering five pairs of helical spur gears and their effect on the transmission error, contact pattern and vibration level on the transmission.

Keywords: gears, whine noise, manufacturing variability, mount vibration variability

Procedia PDF Downloads 150
1434 Fatigue Life Estimation Using N-Code for Drive Shaft of Passenger Vehicle

Authors: Tae An Kim, Hyo Lim Kang, Hye Won Han, Seung Ho Han

Abstract:

The drive shaft of passenger vehicle has its own function such as transmitting the engine torque from the gearbox and differential gears to the wheels. It must also compensate for all variations in angle or length resulting from manoeuvring and deflection for perfect synchronization between joints. Torsional fatigue failures occur frequently at the connection parts of the spline joints in the end of the drive shaft. In this study, the fatigue life of a drive shaft of passenger vehicle was estimated by using the finite element analysis. A commercial software of n-Code was applied under twisting load conditions, i.e. 0~134kgf•m and 0~188kgf•m, in which the shear strain range-fatigue life relationship considering Signed Shear method, Smith-Watson-Topper equation, Neuber-Hoffman Seeger method, size sensitivity factor and surface roughness effect was taken into account. The estimated fatigue life was verified by a twisting load test of the real drive shaft in a test rig. (Human Resource Training Project for Industry Matched R & D, KIAT, N036200004).

Keywords: drive shaft, fatigue life estimation, passenger vehicle, shear strain range-fatigue life relationship, torsional fatigue failure

Procedia PDF Downloads 275
1433 The Mechanical Properties of In-Situ Consolidated Nanocrystalline Aluminum Alloys

Authors: Khaled M. Youssef, Sara I. Ahmed

Abstract:

In this study, artifacts-free bulk nanocrystalline pure aluminum alloy samples were prepared through mechanical milling under ultra-high purity argon and at both liquid nitrogen and room temperatures. The nanostructure evolution during milling was examined using X-ray diffraction and transmission electron microscope techniques. The in-situ consolidated samples after milling exhibited an average grain size of 18 nm. The tensile properties of this novel material are reported in comparison with coarse-grained aluminum alloys. The 0.2% offset yield strength of the nanocrystalline aluminum was found to be 340 MPa. This value is at least one order of magnitude higher than that of the coarse-grained aluminum alloy. In addition to this extraordinarily high strength, the nanocrystalline aluminum showed a significant tensile ductility, with 6% uniform elongation and 11% elongation-to-failure. The transmission electron microscope observations in this study provide evidence of deformation twinning in the plastically deformed nanocrystalline aluminum. These results highlight a change of the deformation mechanism from a typical dislocation slip to twinning deformation induced by partial dislocation activities.

Keywords: nanocrystalline, aluminum, strength, ductility

Procedia PDF Downloads 182
1432 Use and Health Effects of Caffeinated Beverages in Omani Students

Authors: Nasiruddin Khan

Abstract:

The increased use of caffeinated beverages and energy drink is posing threat to all ages and gender especially, younger adults. There is a lack of scientific evidence in Oman regarding caffeine and energy drink consumption. Our study aims to demonstrate the prevalence, pattern, knowledge and awareness, and side effects of caffeine intake among university students. This cross-sectional study including (N=365) apparently healthy male and female Omani university students aged 18-30 years, was carried out from February 2018-June 2018. A self-administered questionnaire with various sections was used to obtain information. The prevalence of caffeinated beverage consumption was commonly high among participants (97%). The males preferred Nescafe, coffee (both p < 0.001), espresso (p < 0.022), and soda (p < 0.008) while females consumed more tea (p < 0.029). The awareness about negative health impact of caffeine intake was significantly higher in females rather than males (p < 0.002). The overall prevalence of energy drink consumption was 42.1% (n=149), and higher in males (75%, p < 0.001). More males consumed 3-5 and > 5 cans/day while females used 1-2 cans/day. The starting age of energy drink use was higher in females (16-20 years (51.1%)) as compared to males (11-15 years (33.3%)). Females were more aware of caffeine as energy drink ingredient (p < 0.036) than males. The major source of information about enery drink was family and friends (58.3%). Red Bull was the commonly used brand (55.5%) among participants. Common reasons for high energy drink consumption were energy boost (68.4 %), taste (62.9%), reduce fatigue (52.1%), and better performance (47.3%). Females reported breathing problem, and abnormal heart beat (p < 0.004, 0.054, respectively), while more males reported irritability than females (p < 0.052). The prevalence of caffeinated beverage and energy drink consumption is high among participants. The awareness, and knowledge among university student is not satisfactory and needs immediate action to avoid excess use of such consumption.

Keywords: energy drink, caffeinated beverages, awareness, Oman

Procedia PDF Downloads 131
1431 Broad Protection against Avian Influenza Virus by Using a Modified Vaccinia Ankara Virus Expressing a Mosaic Hemagglutinin

Authors: Attapon Kamlangdee, Brock Kingstad-Bakke, Tavis K. Anderson, Tony L. Goldberg, Jorge E. Osorio

Abstract:

A critical failure in our preparedness for an influenza pandemic is the lack of a universal vaccine. Influenza virus strains diverge by 1 to 2% per year, and commercially available vaccines often do not elicit protection from one year to the next, necessitating frequent formulation changes. This represents a major challenge to the development of a cross-protective vaccine that can protect against circulating viral antigenic diversity. We have constructed a recombinant modified vaccinia virus Ankara (MVA) that expresses an H5N1 mosaic hemagglutinin (H5M) (MVA-H5M). This mosaic was generated in silico using 2,145 field-sourced H5N1 isolates. A single dose of MVA-H5M provided 100% protection in mice against clade 0, 1, and 2 avian influenza viruses and also protected against seasonal H1N1 virus (A/Puerto Rico/8/34). It also provided short-term (10 days) and long-term (6 months) protection post vaccination. Both neutralizing antibodies and antigen-specific CD4+and CD8+ T cells were still detected at 5 months post vaccination, suggesting that MVA-H5M provides long-lasting immunity.

Keywords: modified vaccinia Ankara, MVA, H5N1, hemagglutinin, influenza vaccine

Procedia PDF Downloads 279
1430 Optimizing the Public Policy Information System under the Environment of E-Government

Authors: Qian Zaijian

Abstract:

E-government is one of the hot issues in the current academic research of public policy and management. As the organic integration of information and communication technology (ICT) and public administration, e-government is one of the most important areas in contemporary information society. Policy information system is a basic subsystem of public policy system, its operation affects the overall effect of the policy process or even exerts a direct impact on the operation of a public policy and its success or failure. The basic principle of its operation is information collection, processing, analysis and release for a specific purpose. The function of E-government for public policy information system lies in the promotion of public access to the policy information resources, information transmission through e-participation, e-consultation in the process of policy analysis and processing of information and electronic services in policy information stored, to promote the optimization of policy information systems. However, due to many factors, the function of e-government to promote policy information system optimization has its practical limits. In the building of E-government in our country, we should take such path as adhering to the principle of freedom of information, eliminating the information divide (gap), expanding e-consultation, breaking down information silos and other major path, so as to promote the optimization of public policy information systems.

Keywords: China, e-consultation, e-democracy, e-government, e-participation, ICTs, public policy information systems

Procedia PDF Downloads 865
1429 Polyphenols: Isolation, Purification, Characterization and Evaluation of Various Biological Activities

Authors: Abdullah Ijaz Hussain

Abstract:

The purpose of this study was to explore the cardioprotective and anti-inflammatory effects of polyphenol-rich extracts from cucurbitaceae family members, including Cucurbita pepo, C. moschata, and C. maxima, on rat models. The initial crude extracts from these cucurbits were further separated into hexane, chloroform, ethyl acetate, butanol, and aqueous ethanol fractions, labeled as HEF, CHF, EAF, BUF, and AEF, respectively. Of these, AEF yielded the highest amount, followed by BUF, HEF, EAF, and CHF in descending order. Notably, EAF contained the greatest concentration of total phenolics, flavonoids, and flavonols. In terms of antioxidant activity, EAF demonstrated the most potent DPPH radical scavenging capability, succeeded by CHF, BUF, AEF, and HEF. EAF also exhibited the strongest reducing potential among the fractions. RP-HPLC analysis identified various phenolic acids and flavonoids across the cucurbita fractions, including ferulic acid, vanillic acid, p-coumeric acid, gallic acid, p-hydroxybenzoic acid, chlorogenic acid, catechin, rutin, quercetin, myricetin, and kaempferol. Doses of 250 and 500 mg/kg body weight of cucurbita fractions were administered orally to male WKY rats daily for 21 days. The rats' body weight, heart rate, and blood pressure were monitored bi-weekly. Oxidative status assessments were conducted using plasma samples to measure levels of malondialdehyde (MDA), superoxide dismutase (SOD), reduced glutathione (GSH), nitric oxide (NO), and total antioxidant capacity (TAC). At the study's conclusion, surgical assessments, including blood pressure, pulse wave velocity (PWV), and echocardiograms (ECG) were performed. The findings indicated that EAF from cucurbita significantly enhanced antihypertensive and antioxidant activities in the SHR rat group.

Keywords: polyphenols, chlorogenic acid, antihypertensive activity, oxidative stress, lcms

Procedia PDF Downloads 23
1428 Multiscale Syntheses of Knee Collateral Ligament Stresses: Aggregate Mechanics as a Function of Molecular Properties

Authors: Raouf Mbarki, Fadi Al Khatib, Malek Adouni

Abstract:

Knee collateral ligaments play a significant role in restraining excessive frontal motion (varus/valgus rotations). In this investigation, a multiscale frame was developed based on structural hierarchies of the collateral ligaments starting from the bottom (tropocollagen molecule) to up where the fibred reinforced structure established. Experimental data of failure tensile test were considered as the principal driver of the developed model. This model was calibrated statistically using Bayesian calibration due to the high number of unknown parameters. Then the model is scaled up to fit the real structure of the collateral ligaments and simulated under realistic boundary conditions. Predications have been successful in describing the observed transient response of the collateral ligaments during tensile test under pre- and post-damage loading conditions. Collateral ligaments maximum stresses and strengths were observed near to the femoral insertions, a results that is in good agreement with experimental investigations. Also for the first time, damage initiation and propagation were documented with this model as a function of the cross-link density between tropocollagen molecules.

Keywords: multiscale model, tropocollagen, fibrils, ligaments commas

Procedia PDF Downloads 160