Search results for: core length
1109 Bridge Damage Detection and Stiffness Reduction Using Vibration Data: Experimental Investigation on a Small Scale Steel Bridge
Authors: Mirco Tarozzi, Giacomo Pignagnoli, Andrea Benedetti
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The design of planning maintenance of civil structures often requires the evaluation of their level of safety in order to be able to choose which structure, and in which measure, it needs a structural retrofit. This work deals with the evaluation of the stiffness reduction of a scaled steel deck due to the presence of localized damages. The dynamic tests performed on it have shown the variability of its main frequencies linked to the gradual reduction of its rigidity. This deck consists in a steel grillage of four secondary beams and three main beams linked to a concrete slab. This steel deck is 6 m long and 3 m wide and it rests on two abutments made of concrete. By processing the signals of the accelerations due to a random excitation of the deck, the main natural frequencies of this bridge have been extracted. In order to assign more reliable parameters to the numerical model of the deck, some load tests have been performed and the mechanical property of the materials and the supports have been obtained. The two external beams have been cut at one third of their length and the structural strength has been restored by the design of a bolted plate. The gradual loss of the bolts and the plates removal have made the simulation of localized damage possible. In order to define the relationship between frequency variation and loss in stiffness, the identification of its natural frequencies has been performed, before and after the occurrence of the damage, corresponding to each step. The study of the relationship between stiffness losses and frequency shifts has been reported in this paper: the square of the frequency variation due to the presence of the damage is proportional to the ratio between the rigidities. This relationship can be used to quantify the loss in stiffness of a real scale bridge in an efficient way.Keywords: damage detection, dynamic test, frequency shifts, operational modal analysis, steel bridge
Procedia PDF Downloads 1591108 Perceptions and Expectations by Participants of Monitoring and Evaluation Short Course Training Programmes in Africa
Authors: Mokgophana Ramasobana
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Background: At the core of the demand to utilize evidence-based approaches in the policy-making cycle, prioritization of limited financial resources and results driven initiatives is the urgency to develop a cohort of competent Monitoring and Evaluation (M&E) practitioners and public servants. The ongoing strides in the evaluation capacity building (ECB) initiatives are a direct response to produce the highly-sought after M&E skills. Notwithstanding the rapid growth of M&E short courses, participants perceived value and expectation of M&E short courses as a panacea for ECB have not been empirically quantified or measured. The objective of this article is to explicitly illustrate the importance of measuring ECB interventions and understanding what works in ECB and why it works. Objectives: This article illustrates the importance of establishing empirical ECB measurement tools to evaluate ECB interventions in order to ascertain its contribution to the broader evaluation practice. Method: The study was primarily a desktop review of existing literature, juxtaposed by a survey of the participants across the African continent based on the 43 M&E short courses hosted by the Centre for Learning on Evaluation and Results Anglophone Africa (CLEAR-AA) in collaboration with the Department of Planning Monitoring and Evaluation (DPME) Results: The article established that participants perceive short course training as a panacea to improve their M&E practical skill critical to executing their organizational duties. In tandem, participants are likely to demand customized training as opposed to general topics in Evaluation. However, the organizational environments constrain the application of the newly acquired skills. Conclusion: This article aims to contribute to the 'how to' measure ECB interventions discourse and contribute towards the improvement to evaluate ECB interventions. The study finds that participants prefer training courses with longer duration to cover more topics. At the same time, whilst organizations call for customization of programmes, the study found that individual participants demand knowledge of generic and popular evaluation topics.Keywords: evaluation capacity building, effectiveness and training, monitoring and evaluation (M&E) short course training, perceptions and expectations
Procedia PDF Downloads 1281107 Practical Experiences in the Development of a Lab-Scale Process for the Production and Recovery of Fucoxanthin
Authors: Alma Gómez-Loredo, José González-Valdez, Jorge Benavides, Marco Rito-Palomares
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Fucoxanthin is a carotenoid that exerts multiple beneficial effects on human health, including antioxidant, anti-cancer, antidiabetic and anti-obesity activity; making the development of a whole process for its production and recovery an important contribution. In this work, the lab-scale production and purification of fucoxanthin in Isocrhysis galbana have been studied. In batch cultures, low light intensities (13.5 μmol/m2s) and bubble agitation were the best conditions for production of the carotenoid with product yields of up to 0.143 mg/g. After fucoxanthin ethanolic extraction from biomass and hexane partition, further recovery and purification of the carotenoid has been accomplished by means of alcohol – salt Aqueous Two-Phase System (ATPS) extraction followed by an ultrafiltration (UF) step. An ATPS comprised of ethanol and potassium phosphate (Volume Ratio (VR) =3; Tie-line Length (TLL) 60% w/w) presented a fucoxanthin recovery yield of 76.24 ± 1.60% among the studied systems and was able to remove 64.89 ± 2.64% of the carotenoid and chlorophyll pollutants. For UF, the addition of ethanol to the original recovered ethanolic ATPS stream to a final relation of 74.15% (w/w) resulted in a reduction of approximately 16% of the protein contents, increasing product purity with a recovery yield of about 63% of the compound in the permeate stream. Considering the production, extraction and primary recovery (ATPS and UF) steps, around a 45% global fucoxanthin recovery should be expected. Although other purification technologies, such as Centrifugal Partition Chromatography are able to obtain fucoxanthin recoveries of up to 83%, the process developed in the present work does not require large volumes of solvents or expensive equipment. Moreover, it has a potential for scale up to commercial scale and represents a cost-effective strategy when compared to traditional separation techniques like chromatography.Keywords: aqueous two-phase systems, fucoxanthin, Isochrysis galbana, microalgae, ultrafiltration
Procedia PDF Downloads 4231106 Effects of Injectable Thermosensitive Hydrogel Containing Chitosan as a Barrier for Prevention of Post-operative Peritoneal Adhesion in Rats
Authors: Sara Javanmardi, Sepehr Aziziz, Baharak Divband, Masoumeh Firouzamandi
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Post-operative adhesions are the most common cause of intestinal obstruction, female infertility and chronic abdominal pain. We developed a novel approach for preventing post-operative peritoneal adhesions using a biodegradable and thermosensitive curcumin hydrogel in rats. Thirteen male Sprague-Dawley rats were assigned randomly into five groups of six animals each: In SHAM group, the cecum was exteriorized, gently manipulated and sent back into the abdomen. In CONTROL group, the surgical abrasion was performed with no further treatment. In Hydrogel group, surgical abrasion was performed with local application of blank hydrogel (1 mL). In Curcumin group, surgical abrasion was performed with local application of curcumin (1 mL). In CUR/HGEL group, surgical abrasion was performed with local application of curcumin hydrogel (1 mL). On day 10, adhesions were assessed using a standardized scale (Evans model), and samples were collected for the Real-time PCR. Real-time PCR was performed to determine mRNA levels of VCAM-1, ICAM-1 and GAPDH. The macroscopic adhesion intensity showed statistically significant differences between the CUR/HGEL and other groups (P=0.0005). The findings of the present study revealed there were statistically significant differences between the groups regarding adhesion band length and numbers (P<0.0001). The protein and mRNA expression of VCAM-1 and ICAM-1 in secal tissues were significantly down regulated due to curcumin-hydrogel application in CUR/HGEL compared to other groups (p<0.05). The thermosensitive hydrogel could reduce the severity and even prevent formation of intra-abdominal adhesion. Curcumin hydrogel could serve as a potential barrier agent to prevent post-operative peritoneal adhesion in rats.Keywords: peritoneal adhesion, hydrogel, curcumijn, ICAM-1, VCAM-1
Procedia PDF Downloads 871105 Performances of Ashwagandha (Withania somnifera Duanal) as Affected by Method of Planting and Source of Nutrients
Authors: Ewon Kaliyadasa, U. L. B. Jayasinghe, S. E. Peiris
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Ashwagandha (Withania sominifera Duanal) is an important medicinal herb belongs to family Solanaceae. This plant has raised its popularity after discovering anti stress and sex stimulating properties that mainly due to the presence of biologically active alkaloid compounds. Therefore it is vital to adapt to a proper agro technological package that ensure optimum growth of ashwagandha to obtain the finest quality without degrading pharmacologically active constituents. Organic and inorganic fertilizer mixtures were combined with direct seeding and transplanting as four different treatments in this study. Tuber fresh and dry weights were recorded up to twelve months starting from two months after sowing (MAS) while shoot height, root length, number of leaves, shoot fresh and dry weights and root: shoot ratio up to 6MAS. Results revealed that growth of ashwagandha was not affected significantly by method of planting or type of fertilizer or its combinations during most of the harvests. However, tubers harvested at 6MAS recorded the highest dry tuber weight per plant in all four treatments compared to early harvests where two direct seeded treatments are the best. Chemical comparison of these two treatments, direct seeding coupled with organic and inorganic fertilizer shown that direct seeding with organic treatment recorded the highest values for alkaloid and withaferine A content with lower percentage of fiber. Further these values are in concurring with the values of commercially available tuber samples. Having considered all facts, 6MAS can be recommended as the best harvesting stage to obtain high quality tubers of ashwagandha under local conditions.Keywords: alkaloids, direct seeding, dry tuber weight, inorganic fertilizer, organic fertilizer, transplanting, withaferine a
Procedia PDF Downloads 3421104 Soil Erosion Assessment Using the RUSLE Model, Remote Sensing, and GIS in the Shatt Al-Arab Basin (Iraq-Iran)
Authors: Hadi Allafta, Christian Opp
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Soil erosion is a major concern in the Shatt Al-Arab basin owing to the steepness of its topography as well as the remarkable altitudinal deference between the upstream and downstream parts of the basin. Such conditions resulted in soil vulnerability to erosion; huge amounts of soil are annually transported, creating enormous implications such as land degradation, structure damage, biodiversity loss, productivity decline, etc. Thus, evaluation of soil erosion risk and its spatial distribution is crucial to build adatabase for efficient control measures. The present study used revised universal soil loss equation (RUSLE) model integrated with Geographic Information System (GIS) for depicting soil erosion hazard zones in the Shatt Al-Arab basin. The RUSLE model incorporated several parameters such as rainfall-runoff erosivity, soil erodibility, slope length and steepness, land cover and management, and conservation support practice for soil erosion zonation. High to medium soil loss of 100 to 20 ton perhectare per year represents around 25% of the basin area, while the areas of low soil loss of less than 20 ton per hectare per year occupied the rest of the total area. The high soil loss rates are linked to areas of high rainfall levels, loamy soil domination, elevated terrains/plateau margins with steep side slope, and high cultivation activities. The findings of the current study can be useful for managers and policy makers in the implementation of a suitable conservation program to reduce soil erosion or to recommend soil conservation acts if development projects are to be continued at regions of high soil erosion risk.Keywords: geographic information system, revised universal soil loss equation, shatt Al-Arab basin, soil erosion
Procedia PDF Downloads 1231103 Left Posterior Pericardiotomy in the Prevention of Post-Operative Atrial Fibrillation and Cardiac Tamponade: A Retrospective Study of 2118 Isolated Coronary Artery Bypass Graft Patients
Authors: Ayeshmanthe Rathnayake, Siew Goh, Carmel Fenton, Ashutosh Hardikar
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Post-Operative Atrial Fibrillation (POAF) is the most frequent complication of cardiac surgery and is associated with reduced survival, increased rates of cognitive changes and cerebrovascular accident, heart failure, renal dysfunction, infection and length of stay, and hospital costs. Cardiac tamponade, although less common, carries high morbidity and mortality. Shed mediastinal blood in the pericardial space is a major source of intrapericardial oxidative stress and inflammation that triggers POAF. The utilisation of a left posterior pericardiotomy aims to shunt blood from the pericardium into the pleural space and have a role in the prevention of POAF as well as cardiac tamponade. 2118 patients had undergone isolated Coronary Artery Bypass Graft (CABG) at Royal Hobart Hospital from 2008-2021. They were divided into pericardiotomy vs control group. Patient baseline demographics, intraoperative data, and post-operative outcomes were reviewed retrospectively. Total incidence of new POAF and cardiac tamponade was 26.1% and 0.75%, respectively. Primary outcome of both the incidence of POAF(22.9% vs27.8%OR 0.77 p<0.05) and Cardiac Tamponade (0% vs 1.1% OR 0.85 p<0.05) were less in the pericardiotomy group.Increasing age, BMI, poor left ventricular function (EF <30%), and return to theatre were independent predictors of developing POAF. There were similar rates of return to theatre for bleeding however, no cases of tamponade in the pericardiotomy group. There were no complications attributable to left posterior pericardiotomy and the time added to the duration of surgery was minimal. Left posterior pericardiotomy is associated with a significant reduction in the incidence of POAFand cardiac tamponade and issafe and efficient.Keywords: cardiac surgery, pericardiotomy, post-operative atrial fibrillation, cardiac tamponade
Procedia PDF Downloads 891102 Genetic Polymorphism of Milk Protein Gene and Association with Milk Production Traits in Local Latvian Brown Breed Cows
Authors: Daina Jonkus, Solvita Petrovska, Dace Smiltina, Lasma Cielava
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The beta-lactoglobulin and kappa-casein are milk proteins which are important for milk composition. Cows with beta-lactoglobulin and kappa-casein gene BB genotypes have highest milk crude protein and fat content. The aim of the study was to determinate the frequencies of milk protein gene polymorphisms in local Latvian Brown (LB) cows breed and analyze the influence of beta-lactoglobulin and kappa-casein genotypes to milk productivity traits. 102 cows’ genotypes of milk protein genes were detected using Polymerase Chain Reaction and Restriction Fragment Length Polymorphism (PCR-RFLP) and electrophoresis on 3% agarose gel. For beta-lactoglobulin were observed 2 types of alleles A and B and for kappa-casein 3 types: A, B and E. Highest frequency in beta-lactoglobulin gene was observed for B allele – 0.926. Molecular analysis of beta-lactoglobulin gene shows 86.3% of individuals are homozygous by B allele and animals are with genotypes BB and 12.7% of individuals are heterozygous with genotypes AB. The highest milk yield 4711.7 kg was for 1st lactation cows with AB genotypes, whereas the highest milk protein content (3.35%) and fat content (4.46 %) was for BB genotypes. Analysis of the kappa-casein locus showed a prevalence of the A allele – 0.750. The genetic variant of B was characterized by a low frequency – 0.240. Moreover, the frequency of E occurred in the LB cows’ population with very low frequency – 0.010. 54.9 % of cows are homozygous with genotypes AA, and only 4.9 % are homozygous with genotypes BB. 32.8 % of individuals are heterozygous with genotypes AB, and 2.0 % are with AE. The highest milk productivity was for 1st lactation cows with AB genotypes: milk yield 4620.3 kg, milk protein content 3.39% and fat content 4.53 %. According to the results, in local Latvian brown there are only 2.9% of cows are with BB-BB genotypes, which is related to milk coagulation ability and affected cheese production yield. Acknowledgment: the investigation is supported by VPP 2014-2017 AgroBioRes Project No. 3 LIVESTOCK.Keywords: beta-lactoglobulin, cows, genotype frequencies, kappa-casein
Procedia PDF Downloads 2711101 The Greek Revolution Through the Foreign Press: The Case of Newspaper the London Times in the Period 1821-1828
Authors: Euripides Antoniades
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In 1821, the Greek Revolution movement, under the political influence that arose from the French revolution, and the corresponding movements in Italy, Germany and America, demanded the liberation of the nation and the establishment of an independent national state. Published topics in the British press regarding the Greek Revolution, focused on: a)the right of the Greeks to claim their freedom from Turkish domination in order to establish an independent state based on the principle of national autonomy, b)criticism regarding Turkish rule as illegal and the power of the Ottoman Sultan as arbitrary, c)the recognition of the Greek identity and its distinction from the Turkish one and d)the endorsement Greeks as the descendants of ancient Greeks. The London Times is a print publication that presents, in chronological or thematic order, the news, opinions or announcements about the most important events that have occurred in a place during a specified period of time. A combination of qualitative and quantitative content analysis was applied. An attempt was made to record Greek Revolution references along with the usage of specific words and expressions that contribute to the representation of the historical events and their exposure to the reading public. Key finds of this research reveal that a)there was a frequency of passionate daily articles concerning the events in Greece, their length, and context in The Times of London, b)he British public opinion was influenced by this particular newspaper and c) he newspaper published various news about the revolution by adopting the role of animator of the Greek struggle. In fact, this type of news was the main substance of the The London Times’ structure, establishing a positive image about the Greek Revolution contributing to the European diplomatic development. These factors offered a change in the attitude of the British and Russians respectively assuming a positive approach towards Greece.Keywords: Greece, revolution, press, the london times, great britain, mass media
Procedia PDF Downloads 851100 A Prospective Randomised Observational Study of Obstructed Total Anamalous Pulmonary Venous Connection (TAPVC) Repair Patients
Authors: Sanjeev Singh
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Background: Obstructed total anomalous pulmonary venous connection (OTAPVC) typically presents with severe cardiovascular decompensation and requires urgent surgical management. Pulmonary arterial hypertension (PAH) is a major risk factor affecting mortality. Perioperative management focuses on providing inotropic support and managing potential pulmonary hypertensive episodes. The aim of this study was to determine the outcome of patients with high pulmonary arterial pressure (PAP) with milrinone alone and a combination of milrinone and inhaled nitric oxide (INO). Material and Methods: After the approval of the ethical committee, this single-center prospective randomized and observational study was conducted over a period of two years among eighty-six patients with obstructed TAPVC repair with severe PAH. Group-I patients received milrinone, and Group-II patients received both milrinone (after aortic cross-clamp removal) and INO during the post-operative period at the cardiac care unit (CCU). Clinical outcomes such as ventilation time, length of stay (LOS) in the CCU, LOS in the hospital, complications, and hospital mortality were compared between the two groups. Result: The average ventilation time, LOS in CCU, and LOS in hospital for group I were 96.82 ± 19.46 hours, 10.91 ± 7.53 days, and 14.46 ± 7.58 days, respectively, and for group II, it was 85.14 ± 15.79 hours, 7.28 ± 3.68 days, and 10.21 ± 3.14 days, respectively, which was statistically significantly lower for group II. Reintubation, RV dysfunction, and hospital mortality were 16.3%, 37.2%, and 6.9% in group I, and 4.8%, 14.6%, and 2.4% in group II, respectively. The P value for each variable was significant < 0.05 (except mortality). Conclusion: Preoperative obstruction is a risk factor for postoperative obstruction, as 235 patients with obstructed TAPVC had severe PAH (39.98%) in this study. Management of severe PAH with a combination of milrinone and INO had a better outcome than milrinone alone.Keywords: inhaled nitric oxide, milrinone, pulmonary artery hypertension, total anomalous pulmonary venous connection
Procedia PDF Downloads 201099 SUMOylation Enhances Nurr1/1a Mediated Transactivation in a Neuronal Cell Type
Authors: Jade Edey, Andrew Bennett, Gareth Hathway
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Nuclear receptor-related 1 protein (also known as Nurr1 or NR4A2) is an orphan nuclear receptor which plays a vital role in the development, survival and maintenance of dopaminergic (DA) neurons particularly in the substantia nigra (SN). Increasing research has investigated Nurr1’s additional role within microglia and astrocytes where it has been suggested to act as a negative regulator of inflammation; potentially offering neuroprotection. Considering both DA neurodegeneration and neuroinflammation are commonly accepted constituents of Parkinson’s Disease (PD), understanding the mechanisms by which Nurr1 regulates inflammatory processes could provide an attractive therapeutic target. Nurr1 regulates inflammation via a transrepressive mechanism possibly dependent upon SUMOylation. In addition, Nurr1 can transactivate numerous genes involved in DA synthesis, such as Tyrosine Hydroxylase (TH). A C-terminal splice variant of Nurr1, Nurr-1a, has been reported in both neuronal and glial cells. However, research into its transcriptional activity is minimal. We employed in vitro methods such as SUMO-Pulldown experiments alongside Luciferase reporter assays to investigate the SUMOylation status and transactivation capabilities of Nurr1 and Nurr-1a respectively. The SUMO-Pulldown assay demonstrated Nurr-1a undergoes significantly more SUMO modification than its full-length variant. Consequently, despite having less transcriptional activation than Nurr1, Nurr1a may play a more prominent role in repression of microglial inflammation. Contrary to published literature we also identified that SUMOylation enhances transcriptional activation by Nurr1 and Nurr1a. SUMOylation-dependent increases in Nurr1 and Nurr1a transcriptional activation were only evident in neuronal SHSY5Y cells but not in HEK293 cells. This research provides novel insight into the regulation of Nurr-1a and indicates differential effects of SUMOylation dependent regulation in neuronal and inflammatory cells.Keywords: nuclear receptors, Parkinson’s disease, inflammation, transcriptional regulation
Procedia PDF Downloads 1531098 Evaluation of Solid-Gas Separation Efficiency in Natural Gas Cyclones
Authors: W. I. Mazyan, A. Ahmadi, M. Hoorfar
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Objectives/Scope: This paper proposes a mathematical model for calculating the solid-gas separation efficiency in cyclones. This model provides better agreement with experimental results compared to existing mathematical models. Methods: The separation ratio efficiency, ϵsp, is evaluated by calculating the outlet to inlet count ratio. Similar to mathematical derivations in the literature, the inlet and outlet particle count were evaluated based on Eulerian approach. The model also includes the external forces acting on the particle (i.e., centrifugal and drag forces). In addition, the proposed model evaluates the exact length that the particle travels inside the cyclone for the evaluation of number of turns inside the cyclone. The separation efficiency model derivation using Stoke’s law considers the effect of the inlet tangential velocity on the separation performance. In cyclones, the inlet velocity is a very important factor in determining the performance of the cyclone separation. Therefore, the proposed model provides accurate estimation of actual cyclone separation efficiency. Results/Observations/Conclusion: The separation ratio efficiency, ϵsp, is studied to evaluate the performance of the cyclone for particles ranging from 1 microns to 10 microns. The proposed model is compared with the results in the literature. It is shown that the proposed mathematical model indicates an error of 7% between its efficiency and the efficiency obtained from the experimental results for 1 micron particles. At the same time, the proposed model gives the user the flexibility to analyze the separation efficiency at different inlet velocities. Additive Information: The proposed model determines the separation efficiency accurately and could also be used to optimize the separation efficiency of cyclones at low cost through trial and error testing, through dimensional changes to enhance separation and through increasing the particle centrifugal forces. Ultimately, the proposed model provides a powerful tool to optimize and enhance existing cyclones at low cost.Keywords: cyclone efficiency, solid-gas separation, mathematical model, models error comparison
Procedia PDF Downloads 3901097 Bowing of a Pipeline from Longitudinal Compressive Stress Induced by Ground Movement
Authors: Gennaro Marino
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This paper concerns a case of a 10.75 inch diameter buried gas transmission line which was exposed to mine subsidence ground movements. The pipeline was buried about 4ft. below the surface with maximum operating pressure of 1440 psi. The mine subsidence movement was the result of long walling ore at a depth of approximately 1600 ft. As ore extraction progressed, the stress in the monitored pipeline worsened and was approaching unacceptable levels. The excessive pipe compression resulted when it was exposed to the compression zone of subsidence basin created by mining. The pipe stress reached a significant compressive level due to the extensive length of the pipe exposed to frictional ground-pipe slip resistance. The backfill ground movement slip resistance depends on normal stress around the pipe, the rate of slip, and the backfill characteristics. Normal stress depends on the burial depth of the backfill density and the lateral subsidence induced stress. The backfill in this site has a soil dry density of approximately 90 PCF. A suite of direct shear tests was conducted a residual friction angle of 36 was determined for the ambient backfill. These tests showed that the residual shearing resistance was reached within a fraction of an inch. The pipe was coated with fusion-bonded epoxy, so friction reduce factory of 0.6 can be considered. To relieve ground movement induced compressive stress, the line was uncovered. As more of the pipeline was exposed, the pipe abruptly bowed in the excavation. An analysis of this pipe formation which was performed is provided in this paper. Also discussed in this paper are ways to mitigate this pipe deformation or upheaval buckling from occurring. Keywords: Pipe Upheaval, Pipe Buckling, Ground subsidence, Buried Pipeline, Pipe Stress Mitigation.Keywords: pipe upheaval, pipe buckling, ground subsidence, buried pipeline, pipe stress mitigation
Procedia PDF Downloads 1591096 Application of Artificial Neural Network for Single Horizontal Bare Tube and Bare Tube Bundles (Staggered) of Large Particles: Heat Transfer Prediction
Authors: G. Ravindranath, S. Savitha
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This paper presents heat transfer analysis of single horizontal bare tube and heat transfer analysis of staggered arrangement of bare tube bundles bare tube bundles in gas-solid (air-solid) fluidized bed and predictions are done by using Artificial Neural Network (ANN) based on experimental data. Fluidized bed provide nearly isothermal environment with high heat transfer rate to submerged objects i.e. due to through mixing and large contact area between the gas and the particle, a fully fluidized bed has little temperature variation and gas leaves at a temperature which is close to that of the bed. Measurement of average heat transfer coefficient was made by local thermal simulation technique in a cold bubbling air-fluidized bed of size 0.305 m. x 0.305 m. Studies were conducted for single horizontal Bare Tube of length 305mm and 28.6mm outer diameter and for bare tube bundles of staggered arrangement using beds of large (average particle diameter greater than 1 mm) particle (raagi and mustard). Within the range of experimental conditions influence of bed particle diameter ( Dp), Fluidizing Velocity (U) were studied, which are significant parameters affecting heat transfer. Artificial Neural Networks (ANNs) have been receiving an increasing attention for simulating engineering systems due to some interesting characteristics such as learning capability, fault tolerance, and non-linearity. Here, feed-forward architecture and trained by back-propagation technique is adopted to predict heat transfer analysis found from experimental results. The ANN is designed to suit the present system which has 3 inputs and 2 out puts. The network predictions are found to be in very good agreement with the experimental observed values of bare heat transfer coefficient (hb) and nusselt number of bare tube (Nub).Keywords: fluidized bed, large particles, particle diameter, ANN
Procedia PDF Downloads 3641095 A Review: The Impact of Core Quality the Empirical Review of Critical Factors on the Causes of Delay in Road Constructions Projects in the GCC Countries
Authors: Sulaiman Al-Hinai, Setyawan Widyarto
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The aim of this study is to identify the critically dominating factors on the delays of road constructions in the GCC countries and their effects on project delivery in Arab countries. Towards the achieved of the objectives the study used the empirical literature from the all relevant online sources and database as many as possible. The findings of this study have summarized and short listed of the success factors in the two categories such as internal and external factors have caused to be influenced to delay of road constructions in the Arab regions. However, in the category of internal factors, there are 63 factors short listed from seven group of factors which has revealed to effects on the delay of road constructions especially, the consultant related factors, the contractor related factors, designed related factors, client related factors, labor related factors, material related issues, equipment related issues respectively. Moreover, for external related factors are also considered to summarized especially natural disaster (flood, hurricanes and cyclone etc.), conflict, war, global financial crisis, compensation delay to affected property owner, price fluctuated, unexpected ground conditions (soil and high-water level), changing of government regulations and laws, delays in obtaining permission from municipality, loss of time by traffic control and restrictions at job site, problem with inhabitant of community, delays in providing service from utilities (water and electricity’s) and accident during constructions accordingly. The present study also concluded the effects of above factors which has delay road constructions through increasing of cost and overrun it, taken overtime, creating of disputes, going for lawsuits, finally happening of abandon of projects. Thus, the present study has given the following recommendations to overcome of above problems by increasing of detailed site investigations, ensure careful monitoring and regular meetings, effective site management, collaborative working and effective coordination’s, proper and comprehensive planning and scheduling and ensure full and intensive commitment from all parties accordingly.Keywords: Arab GCC countries, critical success factors, road constructions delay, project management
Procedia PDF Downloads 1261094 Evaluation of the Shelf Life of Horsetail Stems Stored in Ecological Packaging
Authors: Rosana Goncalves Das Dores, Maira Fonseca, Fernando Finger, Vicente Casali
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Equisetum hyemale L. (horsetail, Equisetaceae) is a medicinal plant used and commercialized in simple paper bags or non-ecological packaging in Brazil. The aim of this work was to evaluate the relation between the bioactive compounds of horsetail stems stored in ecological packages (multi-ply paper sacks) at room temperature. Stems in primary and secondary stage were harvested from an organic estate, on December 2016, selected, measured (length from the soil to the apex (cm), stem diameter at ground level (DGL mm) and breast height (DBH mm) and cut into 10 cm. For the post-harvest evaluations, stems were stored in multi-ply paper sacks and evaluated daily to the respiratory rate, fresh weight loss, pH, presence of fungi / mold, phenolic compounds and antioxidant activity. The analyses were done with four replicates, over time (regression) and compared at 1% significance (Tukey test). The measured heights were 103.7 cm and 143.5 cm, DGL was 2.5mm and 8.4 mm and DBH of 2.59 and 6.15 mm, respectively for primary and secondary stems stage. At both stages of development, in storage in multi-ply paper sacks, the greatest mass loss occurred at 48 h, decaying up to 120 hours, stabilizing at 192 hours. The peak respiratory rate increase occurred in 24 hours, coinciding with a change in pH (temperature and mean humidity was 23.5°C and 55%). No fungi or mold were detected, however, there was loss of color of the stems. The average yields of ethanolic extracts were equivalent (approximately 30%). Phenolic compounds and antioxidant activity were higher in secondary stems stage in up to 120 hours (AATt0 = 20%, AATt30 = 45%), decreasing at the end of the experiment (240 hours). The packaging used allows the commercialization of fresh stems of Equisetum for up to five days.Keywords: paper sacks, phenolic content, antioxidant activity, medicinal plants, post-harvest, ecological packages, Equisetum
Procedia PDF Downloads 1661093 Human TP53 Three Dimentional (3D) Core Domain Hot Spot Mutations at Codon, 36, 72 and 240 are Associated with Oral Squamous Cell Carcinoma
Authors: Saima Saleem, Zubair Abbasi, Abdul Hameed, Mansoor Ahmed Khan, Navid Rashid Qureshi, Abid Azhar
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Oral Squamous Cell Carcinoma (OSCC) is the leading cause of death in the developing countries like Pakistan. This problem aggravates because of the excessive use of available chewing products. In spite of widespread information on their use and purported legislations against their use the Pakistani markets are classical examples of selling chewable carcinogenic mutagens. Reported studies indicated that these products are rich in reactive oxygen species (ROS) and polyphenols. TP53 gene is involved in the suppression of tumor. It has been reported that somatic mutations caused by TP53 gene are the foundation of the cancer. This study aims to find the loss of TP53 functions due to mutation/polymorphism caused by genomic alteration and interaction with tobacco and its related ingredients. Total 260 tissues and blood specimens were collected from OSCC patients and compared with age and sex matched controls. Mutations in exons 2-11 of TP53 were examined by PCR-SSCP. Samples showing mobility shift were directly sequenced. Two mutations were found in exon 4 at nucleotide position 108 and 215 and one in exon 7 at nucleotide position 719 of the coding sequences in patient’s tumor samples. These results show that substitution of proline with arginine at codon 72 and serine with threonine at codon 240 of p53 protein. These polymorphic changes, found in tumor samples of OSCC, could be involved in loss of heterozygocity and apoptotic activity in the binding domain of TP53. The model of the mutated TP53 gene elaborated a nonfunctional unfolded p53 protein, suggesting an important role of these mutations in p53 protein inactivation and malfunction. This nonfunctional 3D model also indicates that exogenous tobacco related carcinogens may act as DNA-damaging agents affecting the structure of DNA. The interpretations could be helpful in establishing the pathways responsible for tumor formation in OSCC patients.Keywords: TP53 mutation/polymorphism, OSCC, PCR-SSCP, direct DNA sequencing, 3D structure
Procedia PDF Downloads 3651092 Hands on Tools to Improve Knowlege, Confidence and Skill of Clinical Disaster Providers
Authors: Lancer Scott
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Purpose: High quality clinical disaster medicine requires providers working collaboratively to care for multiple patients in chaotic environments; however, many providers lack adequate training. To address this deficit, we created a competency-based, 5-hour Emergency Preparedness Training (EPT) curriculum using didactics, small-group discussion, and kinetic learning. The goal was to evaluate the effect of a short course on improving provider knowledge, confidence and skills in disaster scenarios. Methods: Diverse groups of medical university students, health care professionals, and community members were enrolled between 2011 and 2014. The course consisted of didactic lectures, small group exercises, and two live, multi-patient mass casualty incident (MCI) scenarios. The outcome measures were based on core competencies and performance objectives developed by a curriculum task force and assessed via trained facilitator observation, pre- and post-testing, and a course evaluation. Results: 708 participants completed were trained between November 2011 and August 2014, including 49.9% physicians, 31.9% medical students, 7.2% nurses, and 11% various other healthcare professions. 100% of participants completed the pre-test and 71.9% completed the post-test, with average correct answers increasing from 39% to 60%. Following didactics, trainees met 73% and 96% of performance objectives for the two small group exercises and 68.5% and 61.1% of performance objectives for the two MCI scenarios. Average trainee self-assessment of both overall knowledge and skill with clinical disasters improved from 33/100 to 74/100 (overall knowledge) and 33/100 to 77/100 (overall skill). The course assessment was completed by 34.3% participants, of whom 91.5% highly recommended the course. Conclusion: A relatively short, intensive EPT course can improve the ability of a diverse group of disaster care providers to respond effectively to mass casualty scenarios.Keywords: clinical disaster medicine, training, hospital preparedness, surge capacity, education, curriculum, research, performance, training, student, physicians, nurses, health care providers, health care
Procedia PDF Downloads 1911091 Family Medicine Residents in End-of-Life Care
Authors: Goldie Lynn Diaz, Ma. Teresa Tricia G. Bautista, Elisabeth Engeljakob, Mary Glaze Rosal
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Introduction: Residents are expected to convey unfavorable news, discuss prognoses, and relieve suffering, and address do-not-resuscitate orders, yet some report a lack of competence in providing this type of care. Recognizing this need, Family Medicine residency programs are incorporating end-of-life care from symptom and pain control, counseling, and humanistic qualities as core proficiencies in training. Objective: This study determined the competency of Family Medicine Residents from various institutions in Metro Manila on rendering care for the dying. Materials and Methods: Trainees completed a Palliative Care Evaluation tool to assess their degree of confidence in patient and family interactions, patient management, and attitudes towards hospice care. Results: Remarkably, only a small fraction of participants were confident in performing independent management of terminal delirium and dyspnea. Fewer than 30% of residents can do the following without supervision: discuss medication effects and patient wishes after death, coping with pain, vomiting and constipation, and reacting to limited patient decision-making capacity. Half of the respondents had confidence in supporting the patient or family member when they become upset. Majority expressed confidence in many end-of-life care skills if supervision, coaching and consultation will be provided. Most trainees believed that pain medication should be given as needed to terminally ill patients. There was also uncertainty as to the most appropriate person to make end-of-life decisions. These attitudes may be influenced by personal beliefs rooted in cultural upbringing as well as by personal experiences with death in the family, which may also affect their participation and confidence in caring for the dying. Conclusion: Enhancing the quality and quantity of end-of-life care experiences during residency with sufficient supervision and role modeling may lead to knowledge and skill improvement to ensure quality of care. Fostering bedside learning opportunities during residency is an appropriate venue for teaching interventions in end-of-life care education.Keywords: end of life care, geriatrics, palliative care, residency training skill
Procedia PDF Downloads 2561090 A Traditional Settlement in a Modernized City: Yanbu, Saudi Arabia
Authors: Hisham Mortada
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Transition in the urban configuration of Arab cities has never been as radical and visible as it has been since the turn of the last century. The emergence of new cities near historical settlements of Arabia has spawned a series of developments in and around the old city precincts. New developments are based on advanced technology and conform to globally prevalent standards of city planning, superseding the vernacular arrangements based on traditional norms that guided so-called ‘city planning’. Evidence to this fact are the extant Arab buildings present at the urban core of modern cities, which inform us about intricate spatial organization. Organization that subscribed to multiple norms such as, satisfying gender segregation and socialization, economic sustainability, and ensuring security and environmental coherence etc., within settlement compounds. Several participating factors achieved harmony in such an inclusive city—an organization that was challenged and apparently replaced by the new planning order in the face of growing needs of globalized, economy-centric and high-tech models of development. Communities found it difficult to acclimatize with the new western planning models that were implemented at a very large scale throughout the Kingdom, which later experienced spatial re-structuring to suit users’ needs. A closer look the ancient city of Yanbu, now flanked with such new developments, allows us to differentiate and track the beginnings of this unprecedented transition in settlement formations. This paper aims to elaborate the Arabian context offered to both the ‘traditional’ and ‘modern’ planning approaches, in order to understand challenges and solutions offered by both at different times. In the process it will also establish the inconsistencies and conflicts that arose with the shift in planning paradigm, from traditional-'cultural norms’, to modern-'physical planning', in the Arabian context. Thus, by distinguishing the two divergent planning philosophies, their impact of the Arabian morphology, relevance to lifestyle and suitability to the biophysical environment, it concludes with a perspective on sustainability particularly for in case of Yanbu.Keywords: Yanbu, traditional architecture, Hijaz, coral building, Saudi Arabia
Procedia PDF Downloads 3201089 Preparation of Novel Silicone/Graphene-based Nanostructured Surfaces as Fouling Release Coatings
Authors: Mohamed S. Selim, Nesreen A. Fatthallah, Shimaa A. Higazy, Zhifeng Hao, Ping Jing Mo
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As marine fouling-release (FR) surfaces, two new superhydrophobic nanocomposite series of polydimethylsiloxane (PDMS) loaded with reduced graphene oxide (RGO) and graphene oxide/boehmite nanorods (GO-γ-AlOOH) nanofillers were created. The self-cleaning and antifouling capabilities were modified by controlling the nanofillers' shapes and distribution in the silicone matrix. With an average diameter of 10-20 nm and a length of 200 nm, γ-AlOOH nanorods showed a single crystallinity. RGO was made using a hydrothermal process, whereas GO-γ-AlOOH nanocomposites were made using a chemical deposition method for use as fouling-release coating materials. These nanofillers were disseminated in the silicone matrix using the solution casting method to explore the synergetic effects of graphene-based materials on the surface, mechanical, and FR characteristics. Water contact angle (WCA), scanning electron, and atomic force microscopes were used to investigate the surface's hydrophobicity and antifouling capabilities (SEM and AFM). The roughness, superhydrophobicity, and surface mechanical characteristics of coatings all increased the homogeneity of the nanocomposite dispersion. To examine the antifouling effects of the coating systems, laboratory tests were conducted for 30 days using specified bacteria.PDMS/GO-γ-AlOOH nanorod composite demonstrated superior antibacterial efficacy against several bacterial strains than PDMS/RGO nanocomposite. The high surface area and stabilizing effects of the GO-γ-AlOOH hybrid nanofillers are to blame for this. The biodegradability percentage of the PDMS/GO-γ-AlOOH nanorod composite (3 wt.%) was the lowest (1.6%), while the microbial endurability percentages for gram-positive, gram-negative, and fungi were 86.42%, 97.94%, and 85.97%, respectively. The homogeneity of the GO-γ-AlOOH (3 wt.%) dispersion, which had a WCA of 151° and a rough surface, was the most profound superhydrophobic antifouling nanostructured coating.Keywords: superhydrophobic nanocomposite, fouling release, nanofillers, surface coating
Procedia PDF Downloads 2321088 Influence of Thermal Damage on the Mechanical Strength of Trimmed CFRP
Authors: Guillaume Mullier, Jean François Chatelain
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Carbon Fiber Reinforced Plastics (CFRPs) are widely used for advanced applications, in particular in aerospace, automotive and wind energy industries. Once cured to near net shape, CFRP parts need several finishing operations such as trimming, milling or drilling in order to accommodate fastening hardware and meeting the final dimensions. The present research aims to study the effect of the cutting temperature in trimming on the mechanical strength of high performance CFRP laminates used for aeronautics applications. The cutting temperature is of great importance when dealing with trimming of CFRP. Temperatures higher than the glass-transition temperature (Tg) of the resin matrix are highly undesirable: they cause degradation of the matrix in the trimmed edges area, which can severely affect the mechanical performance of the entire component. In this study, a 9.50 mm diameter CVD diamond coated carbide tool with six flutes was used to trim 24-plies CFRP laminates. A 300 m/min cutting speed and 1140 mm/min feed rate were used in the experiments. The tool was heated prior to trimming using a blowtorch, for temperatures ranging from 20°C to 300°C. The temperature at the cutting edge was measured using embedded K-Type thermocouples. Samples trimmed for different cutting temperatures, below and above Tg, were mechanically tested using three-points bending short-beam loading configurations. New cutting tools as well as worn cutting tools were utilized for the experiments. The experiments with the new tools could not prove any correlation between the length of cut, the cutting temperature and the mechanical performance. Thus mechanical strength was constant, regardless of the cutting temperature. However, for worn tools, producing a cutting temperature rising up to 450°C, thermal damage of the resin was observed. The mechanical tests showed a reduced mean resistance in short beam configuration, while the resistance in three point bending decreases with increase of the cutting temperature.Keywords: composites, trimming, thermal damage, surface quality
Procedia PDF Downloads 3201087 Linking Temporal Changes of Climate Factors with Staple Cereal Yields in Southern Burkina Faso
Authors: Pius Borona, Cheikh Mbow, Issa Ouedraogo
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In the Sahel, climate variability has been associated with a complex web of direct and indirect impacts. This natural phenomenon has been an impediment to agro-pastoral communities who experience uncertainty while involving in farming activities which is also their key source of livelihood. In this scenario, the role of climate variability in influencing the performance, quantity and quality of staple cereals yields, vital for food and nutrition security has been a topic of importance. This response of crops and subsequent yield variability is also a subject of immense debate due to the complexity of crop development at different stages. This complexity is further compounded by influence of slowly changing non-climatic factors. With these challenges in mind, the present paper initially explores the occurrence of climate variability at an inter annual and inter decadal level in South Burkina Faso. This is evidenced by variation of the total annual rainfall and the number of rainy days among other climatic descriptors. Further, it is shown how district-scale cereal yields in the study area including maize, sorghum and millet casually associate variably to the inter-annual variation of selected climate variables. Statistical models show that the three cereals widely depict sensitivity to the length of the growing period and total dry days in the growing season. Maize yields on the other hand relate strongly to the rainfall amount variation (R2=51.8%) showing high moisture dependence during critical growth stages. Our conclusions emphasize on adoption of efficient water utilization platforms especially those that have evidently increased yields and strengthening of forecasts dissemination.Keywords: climate variability, cereal yields, seasonality, rain fed farming, Burkina Faso, rainfall
Procedia PDF Downloads 2021086 Impacts of Climate Change on Water Resources Management in the Mahi River Basin of India
Authors: Y. B. Sharma, K. B. Biswas
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This research project examines a 5000 cal yr BP sediment core record to reveal the consequences of human impact and climate variability on the tropical dry forests of the Mahi river basin, western India. To date there has been little research to assess the impact of climate variability and human impact on the vegetation dynamics of this region. There has also been little work to link changes in vegetation cover to documented changes in the basin hydrology over the past 100 years – although it is assumed that the two are closely linked. The key objective of this research project therefore is to understand the driving mechanisms responsible for the abrupt changes in the Mahi river basin as detailed in historical documentation and its impact on water resource management. The Mahi river basin is located in western India (22° 11’-24° 35’ N 72° 46’-74° 52’ E). Mahi river arises in the Malwa Plateau, Madhya Pradesh near Moripara and flows through the uplands and alluvial plain of Rajasthan and Gujarat provinces before draining into the Gulf of Cambay. Palaeoecological procedures (sedimentology, geochemical analysis, C&N isotopes and fossil pollen evidences) have been applied on sedimentary sequences collected from lakes in the Mahi basin. These techniques then facilitate to reconstruct the soil erosion, nutrient cycling, vegetation changes and climatic variability over the last 5000 years. Historical documentation detailing changes in demography, climate and landscape use over the past 100 years in this region will also be collated to compare with the most recent palaeoecological records. The results of the research work provide a detailed record of vegetation change, soil erosion, changes in aridity, and rainfall patterns in the region over the past 5000 years. This research therefore aims to determine the drivers of change and natural variability in the basin. Such information is essential for its current and future management including restoration.Keywords: human impact, climate variability, vegetation cover, hydrology, water resource management, Mahi river basin, sedimentology, geochemistry, fossil pollen, nutrient cycling, vegetation changes, palaeoecology, aridity, rainfall, drivers of change
Procedia PDF Downloads 3721085 The Association between IFNAR2 and Dpp9 Genes Single Nucleotide Polymorphisms Frequency with COVID-19 Severity in Iranian Patients
Authors: Sima Parvizi Omran, Rezvan Tavakoli, Mahnaz Safari, Mohammadreza Aghasadeghi, Abolfazl Fateh, Pooneh Rahimi
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Background: SARS-CoV-2, a single-stranded RNA betacoronavirus causes the global outbreak of coronavirus disease 2019 (COVID-19). Several clinical and scientific concerns are raised by this pandemic. Genetic factors can contribute to pathogenesis and disease susceptibility. There are single nucleotide polymorphisms (SNPs) in many of the genes in the immune system that affect the expression of specific genes or functions of some proteins related to immune responses against viral infections. In this study, we analyzed the impact of polymorphism in the interferon alpha and beta receptor subunit 2 (IFNAR2) and dipeptidyl peptidase 9 (Dpp9) genes and clinical parameters on the susceptibility and resistance to Coronavirus disease (COVID-19). Methods: A total of 330- SARS-CoV-2 positive patients (188 survivors and 142 nonsurvivors) were included in this study. All single-nucleotide polymorphisms (SNPs) on IFNAR2 (rs2236757) and Dpp9 (rs2109069) were genotyped by the polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method. Results: In survivor patients, the frequency of the favourable genotypes of IFNAR2 SNP (rs2236757 GC) was significantly higher than in nonsurvivor patients, and also Dpp9 (rs2109069 AT) genotypes were associated with the severity of COVID-19 infection. Conclusions: This study demonstrated that the severity of COVID- 19 patients was strongly associated with clinical parameters and unfavourable IFNAR2, Dpp9 SNP genotypes. In order to establish the relationship between host genetic factors and the severity of COVID-19 infection, further studies are needed in multiple parts of the world.Keywords: SARS-CoV-2, COVID-19, interferon alpha and beta receptor subunit 2, dipeptidyl peptidase 9, single-nucleotide polymorphisms
Procedia PDF Downloads 1601084 Effectiveness of the Bundle Care to Relieve the Thirst for Intensive Care Unit Patients: Meta-Analysis
Authors: Wen Hsin Hsu, Pin Lin
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Objective: Thirst discomfort is the most common yet often overlooked symptom in patients in the intensive care unit (ICU), with an incidence rate of 69.8%. If not properly cared for, it can easily lead to irritability, affect sleep quality, and increase the incidence of delirium, thereby extending the length of hospital stay. Research points out that the sensation of coldness is an effective strategy to alleviate thirst. Using a combined care approach for thirst can prolong the sensation of coldness in the mouth and reduce thirst discomfort. Therefore, it needs to be further analyzed and its effectiveness reviewed. Methods: This study uses systematic literature review and meta-analysis methodologies and searched databases including PubMed, MEDLINE, EMBASE, Cochrane, CINAHL, and two Chinese databases (CEPS and CJTD) based on keywords. JBI was used to appraise the quality of the literature. RevMen 5.4 software package was used, and Fix Effect Model was applied for data analysis. We selected experimental articles, including those in English and Chinese, that met the inclusion and exclusion criteria. Three research articles were included in total, with a sample size of 416 people. Two were randomized controlled trials, and one was a quasi-experimental design. Results: The results show that the combined care for thirst, which includes ice water spray or oral swab wipes, menthol mouthwash, and lip balm, can significantly relieve thirst intensity MD=-1.36 (3 studies, 95% CI (-1.77, -0.95), p <0.001) and thirst distress MD=-0.71 (2 studies, 95% CI (-1.32, -0.10), p =0.02). Therefore, it is recommended that medical staff identify high-risk groups for thirst early on. Implications for Practice: For patients who cannot eat orally, providing combined care for thirst can increase oral comfort and improve the quality of care.Keywords: thirst bundle care, intensive care units, meta-analysis, ice water spray, menthol
Procedia PDF Downloads 761083 Computational Fluid Dynamics Based Analysis of Heat Exchanging Performance of Rotary Thermal Wheels
Authors: H. M. D. Prabhashana Herath, M. D. Anuradha Wickramasinghe, A. M. C. Kalpani Polgolla, R. A. C. Prasad Ranasinghe, M. Anusha Wijewardane
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The demand for thermal comfort in buildings in hot and humid climates increases progressively. In general, buildings in hot and humid climates spend more than 60% of the total energy cost for the functionality of the air conditioning (AC) system. Hence, it is required to install energy efficient AC systems or integrate energy recovery systems for both new and/or existing AC systems whenever possible, to reduce the energy consumption by the AC system. Integrate a Rotary Thermal Wheel as the energy recovery device of an existing AC system has shown very promising with attractive payback periods of less than 5 years. A rotary thermal wheel can be located in the Air Handling Unit (AHU) of a central AC system to recover the energy available in the return air stream. During this study, a sensitivity analysis was performed using a CFD (Computational Fluid Dynamics) software to determine the optimum design parameters (i.e., rotary speed and parameters of the matrix profile) of a rotary thermal wheel for hot and humid climates. The simulations were performed for a sinusoidal matrix geometry. Variation of sinusoidal matrix parameters, i.e., span length and height, were also analyzed to understand the heat exchanging performance and the induced pressure drop due to the air flow. The results show that the heat exchanging performance increases when increasing the wheel rpm. However, the performance increment rate decreases when increasing the rpm. As a result, it is more advisable to operate the wheel at 10-20 rpm. For the geometry, it was found that the sinusoidal geometries with lesser spans and higher heights have higher heat exchanging capabilities. Considering the sinusoidal profiles analyzed during the study, the geometry with 4mm height and 3mm width shows better performance than the other combinations.Keywords: air conditioning, computational fluid dynamics, CFD, energy recovery, heat exchangers
Procedia PDF Downloads 1271082 Design and Analysis of Deep Excavations
Authors: Barham J. Nareeman, Ilham I. Mohammed
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Excavations in urban developed area are generally supported by deep excavation walls such as; diaphragm wall, bored piles, soldier piles and sheet piles. In some cases, these walls may be braced by internal braces or tie back anchors. Tie back anchors are by far the predominant method for wall support, the large working space inside the excavation provided by a tieback anchor system has a significant construction advantage. This paper aims to analyze a deep excavation bracing system of contiguous pile wall braced by pre-stressed tie back anchors, which is a part of a huge residential building project, located in Turkey/Gaziantep province. The contiguous pile wall will be constructed with a length of 270 m that consists of 285 piles, each having a diameter of 80 cm, and a center to center spacing of 95 cm. The deformation analysis was carried out by a finite element analysis tool using PLAXIS. In the analysis, beam element method together with an elastic perfect plastic soil model and Soil Hardening Model was used to design the contiguous pile wall, the tieback anchor system, and the soil. The two soil clusters which are limestone and a filled soil were modelled with both Hardening soil and Mohr Coulomb models. According to the basic design, both soil clusters are modelled as drained condition. The simulation results show that the maximum horizontal movement of the walls and the maximum settlement of the ground are convenient with 300 individual case histories which are ranging between 1.2mm and 2.3mm for walls, and 15mm and 6.5mm for the settlements. It was concluded that tied-back contiguous pile wall can be satisfactorily modelled using Hardening soil model.Keywords: deep excavation, finite element, pre-stressed tie back anchors, contiguous pile wall, PLAXIS, horizontal deflection, ground settlement
Procedia PDF Downloads 2531081 Growth, Yield and Pest Infestation Response of Maize (Zea mays Linn.) to Biopesticide
Authors: Udomporn Pangnakorn, Settawut Prasatporn, Sombat Chuenchooklin
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The effect of biopesticide on growth, yield and pest infestation of maize (Zea mays Linn.) (variety DK 6818) was evaluated during the drought season. The experimental plots were located at research station of Faculty of Agriculture, Natural Resources and Environment, Naresuan University, Phitsanulok, Thailand. The extracted substance from plants was evaluated in the plots in 4 treatments: 1) water as control; 2) bitter bush (Chromolaena odorata L.); 3) neem (Azadirachta indica A. Juss), 4) golden shower (Cassia fistula Linn.). The experiment was followed a Randomized Complete Block Design (RCBD) with 4 treatments and 4 replications per treatment. The results showed that golden shower gave the highest growth of maize in term of height (203.29 cm), followed by neem and bitter bush with average height of 202.66 cm and 191.66 cm respectively with significance different. But neem treatment given significantly higher average of yield component in term of length, width, and weight of pod corn with 18.89 cm 13.91 cm and 166.46 g respectively. Also, treatment of neem showed the highest harvested yield at 284.06 kg/ha followed by the golden shower and bitter bush with harvested yield at 245.86 kg/ha and 235.52 kg/ha respectively. Additionally, treatment of neem and golden shower were the highest effectiveness for reducing insects pest infestation of maize: corn leaf aphid Rhopalosiphum maidis Fitch, corn borer Ostrinia fumacalis Guenee and corn armyworm Mythimna separata Walker. The treatment of neem, golden shower, and bitter bush given reduction insect infestation on maize with leaves area were infested at 5,412 mm², 6,827 mm² and 8,910 mm² respectively with significance different when compared to control.Keywords: maize, Zea mays Linn., biopesticide, bitter bush, Chromolaena odorata L.), neem, Azadirachta indica A. Juss, golden shower, Cassia fistula Linn.
Procedia PDF Downloads 3201080 Role of Spatial Variability in the Service Life Prediction of Reinforced Concrete Bridges Affected by Corrosion
Authors: Omran M. Kenshel, Alan J. O'Connor
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Estimating the service life of Reinforced Concrete (RC) bridge structures located in corrosive marine environments of a great importance to their owners/engineers. Traditionally, bridge owners/engineers relied more on subjective engineering judgment, e.g. visual inspection, in their estimation approach. However, because financial resources are often limited, rational calculation methods of estimation are needed to aid in making reliable and more accurate predictions for the service life of RC structures. This is in order to direct funds to bridges found to be the most critical. Criticality of the structure can be considered either form the Structural Capacity (i.e. Ultimate Limit State) or from Serviceability viewpoint whichever is adopted. This paper considers the service life of the structure only from the Structural Capacity viewpoint. Considering the great variability associated with the parameters involved in the estimation process, the probabilistic approach is most suited. The probabilistic modelling adopted here used Monte Carlo simulation technique to estimate the Reliability (i.e. Probability of Failure) of the structure under consideration. In this paper the authors used their own experimental data for the Correlation Length (CL) for the most important deterioration parameters. The CL is a parameter of the Correlation Function (CF) by which the spatial fluctuation of a certain deterioration parameter is described. The CL data used here were produced by analyzing 45 chloride profiles obtained from a 30 years old RC bridge located in a marine environment. The service life of the structure were predicted in terms of the load carrying capacity of an RC bridge beam girder. The analysis showed that the influence of SV is only evident if the reliability of the structure is governed by the Flexure failure rather than by the Shear failure.Keywords: Chloride-induced corrosion, Monte-Carlo simulation, reinforced concrete, spatial variability
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