Search results for: climacteric produce
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 2867

Search results for: climacteric produce

1937 Delicate Balance between Cardiac Stress and Protection: Role of Mitochondrial Proteins

Authors: Zuzana Tatarkova, Ivana Pilchova, Michal Cibulka, Martin Kolisek, Peter Racay, Peter Kaplan

Abstract:

Introduction: Normal functioning of mitochondria is crucial for cardiac performance. Mitochondria undergo mitophagy and biogenesis, and mitochondrial proteins are subject to extensive post-translational modifications. The state of mitochondrial homeostasis reflects overall cellular fitness and longevity. Perturbed mitochondria produce less ATP, release greater amounts of reactive molecules, and are more prone to apoptosis. Therefore mitochondrial turnover is an integral aspect of quality control in which dysfunctional mitochondria are selectively eliminated through mitophagy. Currently, the progressive deterioration of physiological functions is seen as accumulation of modified/damaged proteins with limiting regenerative ability and disturbance of such affected protein-protein communication throughout aging in myocardial cells. Methodologies: For our study was used immunohistochemistry, biochemical methods: spectrophotometry, western blotting, immunodetection as well as more sophisticated 2D electrophoresis and mass spectrometry for evaluation protein-protein interactions and specific post-translational modification. Results and Discussion: Mitochondrial stress response to reactive species was evaluated as electron transport chain (ETC) complexes, redox-active molecules, and their possible communication. Protein-protein interactions revealed a strong linkage between age and ETC protein subunits. Redox state was strongly affected in senescent mitochondria with shift in favor of more pro-oxidizing condition within cardiomyocytes. Acute myocardial ischemia and ischemia-reperfusion (IR) injury affected ETC complexes I, II and IV with no change in complex III. Ischemia induced decrease in total antioxidant capacity, MnSOD, GSH and catalase activity with recovery in some extent during reperfusion. While MnSOD protein content was higher in IR group, activity returned to 95% of control. Nitric oxide is one of the biological molecules that can out compete MnSOD for superoxide and produce peroxynitrite. This process is faster than dismutation and led to the 10-fold higher production of nitrotyrosine after IR injury in adult with higher protection in senescent ones. 2D protein profiling revealed 140 mitochondrial proteins, 12 of them with significant changes after IR injury and 36 individual nitrotyrosine-modified proteins further identified by mass spectrometry. Linking these two groups, 5 proteins were altered after IR as well as nitrated, but only one showed massive nitration per lowering content of protein after IR injury in adult. Conclusions: Senescent cells have greater proportion of protein content, which might be modulated by several post-translational modifications. If these protein modifications are connected to functional consequences and protein-protein interactions are revealed, link may lead to the solution. Assume all together, dysfunctional proteostasis can play a causative role and restoration of protein homeostasis machinery is protective against aging and possibly age-related disorders. This work was supported by the project VEGA 1/0018/18 and by project 'Competence Center for Research and Development in the field of Diagnostics and Therapy of Oncological diseases', ITMS: 26220220153, co-financed from EU sources.

Keywords: aging heart, mitochondria, proteomics, redox state

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1936 Genetic Change in Escherichia coli KJ122 That Improved Succinate Production from an Equal Mixture of Xylose and Glucose

Authors: Apichai Sawisit, Sirima Suvarnakuta Jantama, Sunthorn Kanchanatawee, Lonnie O. Ingram, Kaemwich Jantama

Abstract:

Escherichia coli KJ122 was engineered to produce succinate from glucose using the wild type GalP for glucose uptake instead of the native phosphotransferase system (ptsI mutation). This strain ferments 10% (w/v) xylose poorly. Mutants were selected by serial transfers in AM1 mineral salts medium with 10% (w/v) xylose. Evolved mutants exhibited a similar improvement, co-fermentation of an equal mixture of xylose and glucose. One of these, AS1600a, produced 84.26±1.37 g/L succinate, equivalent to that produced by the parent (KJ122) strain from 10% glucose (85.46±1.78 g/L). AS1600a was sequenced and found to contain a mutation in galactose permease (GalP, G236D). Expressing the galP* mutation gene in KJ122ΔgalP resembled the xylose utilization phenotype of the mutant AS1600a. The strain AS1600a and KJ122ΔgalP (pLOI5746; galP*) also co-fermented a mixture of glucose, xylose, arabinose, and galactose in sugarcane bagasse hydrolysate for succinate production.

Keywords: xylose, furfural, succinate, sugarcane bagasse, E. coli

Procedia PDF Downloads 388
1935 Correlation of Empathy with Job Satisfaction and Stress of Social Workers

Authors: Theodosios Paralikas, Evangelia Kotrotsiou, Mairy Gouva, Manolis Mentis, Stiliani Stavrotheodorou, Stiliani Kotrotsiou, Maria Malliarou

Abstract:

There is a big discussion in the international literature on empathy, job satisfaction and job occupational among various of disciplines, including social workers. Νevertheless these parameters have not been specifically studied in the Greek territory. This paper aims to study empathy of social workers, to produce results related to whether empathy is influenced by demographic factors such as gender, age, marital status, level of education and study their perceived stress levels and also the satisfaction they derive from their work. For the first time, an attempt is made to link the empathy of these professionals to their job satisfaction and their anxiety. The sample of this survey consists of 165 social workers working on providers of public and private social services. The results showed that social workers have high levels of empathy contrary to the perceived stress levels which were low to moderate. Regarding the field of the job satisfaction, the survey showed that social workers are very satisfied with their workpiece and workplace. The survey shows no significant relationship between empathy and demographic factors, but there is a significant relationship between empathy and the workpiece/job satisfaction and the feeling of success.

Keywords: empathy, stress, job satisfaction, social workers

Procedia PDF Downloads 176
1934 EnumTree: An Enumerative Biclustering Algorithm for DNA Microarray Data

Authors: Haifa Ben Saber, Mourad Elloumi

Abstract:

In a number of domains, like in DNA microarray data analysis, we need to cluster simultaneously rows (genes) and columns (conditions) of a data matrix to identify groups of constant rows with a group of columns. This kind of clustering is called biclustering. Biclustering algorithms are extensively used in DNA microarray data analysis. More effective biclustering algorithms are highly desirable and needed. We introduce a new algorithm called, Enumerative tree (EnumTree) for biclustering of binary microarray data. is an algorithm adopting the approach of enumerating biclusters. This algorithm extracts all biclusters consistent good quality. The main idea of ​​EnumLat is the construction of a new tree structure to represent adequately different biclusters discovered during the process of enumeration. This algorithm adopts the strategy of all biclusters at a time. The performance of the proposed algorithm is assessed using both synthetic and real DNA micryarray data, our algorithm outperforms other biclustering algorithms for binary microarray data. Biclusters with different numbers of rows. Moreover, we test the biological significance using a gene annotation web tool to show that our proposed method is able to produce biologically relevent biclusters.

Keywords: DNA microarray, biclustering, gene expression data, tree, datamining.

Procedia PDF Downloads 372
1933 Numerical Analysis on the Effect of Abrasive Parameters on Wall Shear Stress and Jet Exit Kinetic Energy

Authors: D. Deepak, N. Yagnesh Sharma

Abstract:

Abrasive Water Jet (AWJ) machining is a relatively new nontraditional machine tool used in machining of fiber reinforced composite. The quality of machined surface depends on jet exit kinetic energy which depends on various operating and material parameters. In the present work the effect abrasive parameters such as its size, concentration and type on jet kinetic energy is investigated using computational fluid dynamics (CFD). In addition, the effect of these parameters on wall shear stress developed inside the nozzle is also investigated. It is found that for the same operating parameters, increase in the abrasive volume fraction (concentration) results in significant decrease in the wall shear stress as well as the jet exit kinetic energy. Increase in the abrasive particle size results in marginal decrease in the jet exit kinetic energy. Numerical simulation also indicates that garnet abrasives produce better jet exit kinetic energy than aluminium oxide and silicon carbide.

Keywords: abrasive water jet machining, jet kinetic energy, operating pressure, wall shear stress, Garnet abrasive

Procedia PDF Downloads 377
1932 Dynamics of the Coupled Fitzhugh-Rinzel Neurons

Authors: Sanjeev Kumar Sharma, Arnab Mondal, Ranjit Kumar Upadhyay

Abstract:

Excitable cells often produce different oscillatory activities that help us to understand the transmitting and processing of signals in the neural system. We consider a FitzHugh-Rinzel (FH-R) model and studied the different dynamics of the model by considering the parameter c as the predominant parameter. The model exhibits different types of neuronal responses such as regular spiking, mixed-mode bursting oscillations (MMBOs), elliptic bursting, etc. Based on the bifurcation diagram, we consider the three regimes (MMBOs, elliptic bursting, and quiescent state). An analytical treatment for the occurrence of the supercritical Hopf bifurcation is studied. Further, we extend our study to a network of a hundred neurons by considering the bi-directional synaptic coupling between them. In this article, we investigate the alternation of spiking propagation and bursting phenomena of an uncoupled and coupled FH-R neurons. We explore that the complete graph of heterogenous desynchronized neurons can exhibit different types of bursting oscillations for certain coupling strength. For higher coupling strength, all the neurons in the network show complete synchronization.

Keywords: excitable neuron model, spiking-bursting, stability and bifurcation, synchronization networks

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1931 A Nuclear Negotiation Qualitative Case Study with Force Field Analysis

Authors: Onur Yuksel

Abstract:

In today’s complex foreign relations between countries, the nuclear enrichment and nuclear weapon have become a threat for all states in the world. There are couple isolated states which have capacity to produce nuclear weapons such as Iran and North Korea. In this article, Iran nuclear negotiation was analyzed in terms of its relations especially with The United States in order to find the important factors that affect the course of the ongoing nuclear negotiation. In this sense, the Force Field Analysis was used by determining and setting forth Driving and Restraining Forces of the nuclear negotiations in order to see the big picture and to develop strategies that may improve the long-term ongoing Iran nuclear negotiations. It is found that Iran nuclear negotiation heavily depends on breaking down the idea of Iran’s supporting terrorist organizations and being more transparent about nuclear and uranium enrichment. Also, it was found that Iran has to rebuild its relations with Western countries, especially with the United States. In addition, the counties— who contribute to Iran nuclear negotiations— will need to work on the dynamics and drivers of the Israel and Iran relations in order to peacefully transform the conflict between the two states.

Keywords: driving force, Iran nuclear negotiation, restraining force, the force field analysis

Procedia PDF Downloads 158
1930 Effect of Temperature and Time on the Yield of Silica from Rice Husk Ash

Authors: Mohammed Adamu Musa, Shehu Saminu Babba

Abstract:

The technological trend towards waste utilization and cost reduction in industrial processing has attracted use of Rice Husk as a value added material. Both rice husk (RH) and Rice Husk Ash (RHA) has been found suitable for wide range of domestic as well as industrial applications. Therefore, the purpose of this research is to produce high grade sodium silicate from rice husk ash by considering the effect of temperature and time of heating as the process variables. The experiment was performed by heating the rice husk at temperatures 500 °C, 600 °C, 700 °C and 800 °C and time 60min, 90min, 120min and 150min were used to obtain the ash. 1.0M of aqueous sodium hydroxide solution was used to dissolve the silicate from the ash, which contained crude sodium silicate. In addition, the ash was neutralized by adding 5M of HCL until the pH reached 3.5 to give silica gel. At 6000C and 120mins, 94.23% silica was obtained from the RHA. At higher temperatures (700 °C and 800 °C) the percentage yield of silica reduced due to surface melting and carbon fixation in the lattice caused by presence of potassium. For this research, 600 °C is considered to be the optimum temperature for silica production from RHA. Silica produced from RHA can generate aggregate value and can be used in areas such as pulp and paper, plastic and rubber reinforcement industries.

Keywords: burning, rice husk, rice husk ash, silica, silica gel, temperature

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1929 Evaluation of Biosurfactant Production by a New Strain Isolated from the Lagoon of Mar Chica Degrading Gasoline

Authors: Ikram Kamal, Mohamed Blaghen

Abstract:

Pollution caused by petroleum hydrocarbons in terrestrial and aquatic environment is a common phenomenon that causes significant ecological and social problems. Biosurfactant applications in the environmental industries are promising due to their biodegradability, low toxicity and effectiveness in enhancing biodegradation and solubilization of low solubility compounds. Currently, the main application is for enhancement of oil recovery and hydrocarbon bioremediation due to their biodegradability and low critical micelle concentration (CMC). In this study we have investigated the potential of bacterial strains collected aseptically from the lagoon Marchika (water and soil) in Nador, Morocco; for the production of biosurfactants. This study also aimed to optimize the biosurfactant production process by changing the variables that influence the type and amount of biosurfactant produced by these microorganisms such as: carbon sources and also other physical and chemical parameters such as temperature and pH. Emulsification index, methylene blue test and thin layer chromatography (TLC) revealed the ability of strains used in this study to produce compounds that could emulsify gasoline. In addition a GC/MS was used to separate and identify different biosurfactants purified.

Keywords: petroleum hydrocarbons, biosurfactant, biodegradability, critical micelle concentration, lagoon Marchika

Procedia PDF Downloads 359
1928 Techno-Economic Assessment of Aluminum Waste Management

Authors: Hamad Almohamadi, Abdulrahman AlKassem, Majed Alamoudi

Abstract:

Dumping Aluminum (Al) waste into landfills causes several health and environmental problems. The pyrolysis process could treat Al waste to produce AlCl₃ and H₂. Using the Aspen Plus software, a techno-economic and feasibility assessment has been performed for Al waste pyrolysis. The Aspen Plus simulation was employed to estimate the plant's mass and energy balance, which was assumed to process 100 dry metric tons of Al waste per day. This study looked at two cases of Al waste treatment. The first case produces 355 tons of AlCl₃ per day and 9 tons of H₂ per day without recycling. The conversion rate must be greater than 50% in case 1 to make a profit. In this case, the MSP for AlCl₃ is $768/ton. The plant would generate $25 million annually if the AlCl₃ were sold at $1000 per ton. In case 2 with recycling, the conversion has less impact on the plant's profitability than in case 1. Moreover, compared to case 1, the MSP of AlCl₃ has no significant influence on process profitability. In this scenario, if AlCl₃ were sold at $1000/ton, the process profit would be $58 million annually. Case 2 is better than case 1 because recycling Al generates a higher yield than converting it to AlCl₃ and H₂.

Keywords: aluminum waste, aspen plus, process modelling, fast pyrolysis, techno-economic assessment

Procedia PDF Downloads 93
1927 An Analysis of Institutional Audits: Basis for Teaching, Learning and Assessment Framework and Principles

Authors: Nabil El Kadhi, Minerva M. Bunagan

Abstract:

The dynamism in education, particularly in the area of teaching, learning and assessment has caused Higher Education Institutions (HEIs) worldwide to seek for ways to continuously improve their educational processes. HEIs use outcomes of institutional audits, assessments and accreditations, for improvement. In this study, the published institutional audit reports of HEIs in the Sultanate of Oman were analyzed to produce features of good practice; identify challenges along Teaching, Learning Assessment (TLA); and propose a framework that puts major emphasis in having a quality-assured TLA, including a set of principles that can be used as basis in succeeding an institutional visit. The TLA framework, which shows the TLA components, characteristics of the components, related expectation, including implementation tool/ strategy and pitfalls can be used by HEIs to have an adequate understanding of the scope of audit and be able to satisfy institutional audit requirements. The scope of this study can be widened by exploring the other requirements of the Institutional Audits in the Sultanate of Oman, particularly the area on Governance and Management and Student Support Services.

Keywords: accreditation, audit, teaching, learning and assessment, quality assurance

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1926 The Effect of Velocity Increment by Blockage Factor on Savonius Hydrokinetic Turbine Performance

Authors: Thochi Seb Rengma, Mahendra Kumar Gupta, P. M. V. Subbarao

Abstract:

Hydrokinetic turbines can be used to produce power in inaccessible villages located near rivers. The hydrokinetic turbine uses the kinetic energy of the water and maybe put it directly into the natural flow of water without dams. For off-grid power production, the Savonius-type vertical axis turbine is the easiest to design and manufacture. This proposal uses three-dimensional computational fluid dynamics (CFD) simulations to measure the considerable interaction and complexity of turbine blades. Savonius hydrokinetic turbine (SHKT) performance is affected by a blockage in the river, canals, and waterways. Putting a large object in a water channel causes water obstruction and raises local free stream velocity. The blockage correction factor or velocity increment measures the impact of velocity on the performance. SHKT performance is evaluated by comparing power coefficient (Cp) with tip-speed ratio (TSR) at various blockage ratios. The maximum Cp was obtained at a TSR of 1.1 with a blockage ratio of 45%, whereas TSR of 0.8 yielded the highest Cp without blockage. The greatest Cp of 0.29 was obtained with a 45% blockage ratio compared to a Cp max of 0.18 without a blockage.

Keywords: savonius hydrokinetic turbine, blockage ratio, vertical axis turbine, power coefficient

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1925 Optimization of Biodiesel Production from Palm Oil over Mg-Al Modified K-10 Clay Catalyst

Authors: Muhammad Ayoub, Abrar Inayat, Bhajan Lal, Sintayehu Mekuria Hailegiorgis

Abstract:

Biodiesel which comes from pure renewable resources provide an alternative fuel option for future because of limited fossil fuel resources as well as environmental concerns. The transesterification of vegetable oils for biodiesel production is a promising process to overcome this future crises of energy. The use of heterogeneous catalysts greatly simplifies the technological process by facilitating the separation of the post-reaction mixture. The purpose of the present work was to examine a heterogeneous catalyst, in particular, Mg-Al modified K-10 clay, to produce methyl esters of palm oil. The prepared catalyst was well characterized by different latest techniques. In this study, the transesterification of palm oil with methanol was studied in a heterogeneous system in the presence of Mg-Al modified K-10 clay as solid base catalyst and then optimized these results with the help of Design of Experiments software. The results showed that methanol is the best alcohol for this reaction condition. The best results was achieved for optimization of biodiesel process. The maximum conversion of triglyceride (88%) was noted after 8 h of reaction at 60 ̊C, with a 6:1 molar ratio of methanol to palm oil and 3 wt % of prepared catalyst.

Keywords: palm oil, transestrefication, clay, biodiesel, mesoporous clay, K-10

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1924 Technical Parameters Evaluation for Caps to Apucarana/Parana - Brazil APL

Authors: Cruz, G. P., Nagamatsu, R. N., Scacchetti, F. A. P., Merlin, F. K.

Abstract:

This study aims to assess a set of technical parameters that provide quality products to the companies that produce caps, APL Apucarana / PR, the city that produces most Brazilian caps, in order to verify the potential of Brazilian caps to compete with international brands, recognized by the standard of excellence when it comes to quality of its products. The determination of the technical parameters was arbitrated from textile ABNT, a total of six technical parameters, providing eight tests for cotton caps. For the evaluation, we used as reference a leading brand recognized worldwide (based on their sales volume in $) for comparison with 3 companies of the APL Apucarana. The results showed that, of the 8 tests, of 8 tests, the companies Apucarana did not obtain better performance than the competitor. They obtained the same results in three tests and lower performance in 5. Given these values, it is concluded that local caps are not far from reaching the quality of leading brand. It is recommended that the APL companies use the parameters to evaluate their products, using this information to support decision-making that seek to improve both the product design and its production process, enabling the feasibility for faster international recognition . Thus, they may have an edge over its main competitor.

Keywords: technical parameters, making caps, quality, evaluation

Procedia PDF Downloads 345
1923 Parametric Design as an Approach to Respond to Complexity

Authors: Sepideh Jabbari Behnam, Zahrasadat Saide Zarabadi

Abstract:

A city is an intertwined texture from the relationship of different components in a whole which is united in a one, so designing the whole complex and its planning is not an easy matter. By considering that a city is a complex system with infinite components and communications, providing flexible layouts that can respond to the unpredictable character of the city, which is a result of its complexity, is inevitable. Parametric design approach as a new approach can produce flexible and transformative layouts in any stage of design. This study aimed to introduce parametric design as a modern approach to respond to complex urban issues by using descriptive and analytical methods. This paper firstly introduces complex systems and then giving a brief characteristic of complex systems. The flexible design and layout flexibility is another matter in response and simulation of complex urban systems that should be considered in design, which is discussed in this study. In this regard, after describing the nature of the parametric approach as a flexible approach, as well as a tool and appropriate way to respond to features such as limited predictability, reciprocating nature, complex communications, and being sensitive to initial conditions and hierarchy, this paper introduces parametric design.

Keywords: complexity theory, complex system, flexibility, parametric design

Procedia PDF Downloads 365
1922 Flexural Response of Sandwiches with Micro Lattice Cores Manufactured via Selective Laser Sintering

Authors: Emre Kara, Ali Kurşun, Halil Aykul

Abstract:

The lightweight sandwiches obtained with the use of various core materials such as foams, honeycomb, lattice structures etc., which have high energy absorbing capacity and high strength to weight ratio, are suitable for several applications in transport industry (automotive, aerospace, shipbuilding industry) where saving of fuel consumption, load carrying capacity increase, safety of vehicles and decrease of emission of harmful gases are very important aspects. While the sandwich structures with foams and honeycombs have been applied for many years, there is a growing interest on a new generation sandwiches with micro lattice cores. In order to produce these core structures, various production methods were created with the development of the technology. One of these production technologies is an additive manufacturing technique called selective laser sintering/melting (SLS/SLM) which is very popular nowadays because of saving of production time and achieving the production of complex topologies. The static bending and the dynamic low velocity impact tests of the sandwiches with carbon fiber/epoxy skins and the micro lattice cores produced via SLS/SLM were already reported in just a few studies. The goal of this investigation was the analysis of the flexural response of the sandwiches consisting of glass fiber reinforced plastic (GFRP) skins and the micro lattice cores manufactured via SLS under thermo-mechanical loads in order to compare the results in terms of peak load and absorbed energy values respect to the effect of core cell size, temperature and support span length. The micro lattice cores were manufactured using SLS technology that creates the product drawn by a 3D computer aided design (CAD) software. The lattice cores which were designed as body centered cubic (BCC) model having two different cell sizes (d= 2 and 2.5 mm) with the strut diameter of 0.3 mm were produced using titanium alloy (Ti6Al4V) powder. During the production of all the core materials, the same production parameters such as laser power, laser beam diameter, building direction etc. were kept constant. Vacuum Infusion (VI) method was used to produce skin materials, made of [0°/90°] woven S-Glass prepreg laminates. The combination of the core and skins were implemented under VI. Three point bending tests were carried out by a servo-hydraulic test machine with different values of support span distances (L = 30, 45, and 60 mm) under various temperature values (T = 23, 40 and 60 °C) in order to analyze the influences of support span and temperature values. The failure mode of the collapsed sandwiches has been investigated using 3D computed tomography (CT) that allows a three-dimensional reconstruction of the analyzed object. The main results of the bending tests are: load-deflection curves, peak force and absorbed energy values. The results were compared according to the effect of cell size, support span and temperature values. The obtained results have particular importance for applications that require lightweight structures with a high capacity of energy dissipation, such as the transport industry, where problems of collision and crash have increased in the last years.

Keywords: light-weight sandwich structures, micro lattice cores, selective laser sintering, transport application

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1921 A Case Study at Lara's Landfill: Solid Waste Management and Energy Recovery

Authors: Kelly Danielly Da Silva Alcantara, Daniel Fernando Molina Junqueira, Graziella Colato Antonio

Abstract:

The Law No. 12,305/10, established by the National Solid Waste Policy (PNRS), provides major changes in the management and managing scenario of solid waste in Brazil. The PNRS established since changes from population behavior as environmental and the consciousness and commitment of the companies with the waste produced. The objective of this project is to conduct a benchmarking study of the management models of Waste Management Municipal Solid (MSW) in national and international levels emphasizing especially in the European Union (Portugal, France and Germany), which are reference countries in energy development, sustainability and consequently recovery of waste generated. The management that encompasses all stages that are included in this sector will be analyzed by benchmarking, as the collection, transportation, processing/treatment and final disposal of waste. Considering the needs to produce clean energy in Brazil, this study will allow the determination to the best treatment of the waste in order to reduce the amount of waste and increase the lifetime of the landfill. Finally, it intends to identify the energy recovery potential through a study analysis of economic viability, energy and sustainable based on a holistic approach.

Keywords: benchmarking, energy recovery, landfill, municipal solid waste

Procedia PDF Downloads 426
1920 Fluorescent Imaging with Hoechst 34580 and Propidium Iodide in Determination of Toxic Changes of Cyanobacterial Oligopeptides in Rotifers

Authors: Adam Bownik, Małgorzata Adamczuk, Barbara Pawlik-Skowrońska

Abstract:

Certain strains of cyanobacteria, microorganisms forming water blooms, produce toxic secondary metabolites. Although various effects of cyanotoxins in aquatic animals are known, little data can be found on the influence of some cyanobacterial oligopeptides beyond microcystins. The aim of the present study was to determine the toxicity of novel pure cyanobacterial oligopeptides: microginin FR-1 (MGFR1) and anabaenopeptin-A (ANA-A) on a transparent model rotifer Brachionus calyciflorus with the use of fluorescent double staining with Hoechst 34580 and propidium iodide. The obtained results showed that both studied oligopeptides decreased the fluorescence intensity of animals stained with Hoechst 34580 in a concentration-dependent manner. On the other hand, a concentration-dependent increase of propidium iodide fluorescence was noted in the exposed rotifers. The results suggest that MGFR-1 and ANA-A should be considered as a potent toxic agent to freshwater rotifers, and fluorescent staining with Hoechst and propidium iodide may be a valuable tool for determination of toxicity of cyanobacterial oligopeptides in rotifers.

Keywords: cyanobacteria, brachionus, oligopeptides, fluorescent staining, hoechst, propidium iodide

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1919 Revolutionizing Manufacturing: Embracing Additive Manufacturing with Eggshell Polylactide (PLA) Polymer

Authors: Choy Sonny Yip Hong

Abstract:

This abstract presents an exploration into the creation of a sustainable bio-polymer compound for additive manufacturing, specifically 3D printing, with a focus on eggshells and polylactide (PLA) polymer. The project initially conducted experiments using a variety of food by-products to create bio-polymers, and promising results were obtained when combining eggshells with PLA polymer. The research journey involved precise measurements, drying of PLA to remove moisture, and the utilization of a filament-making machine to produce 3D printable filaments. The project began with exploratory research and experiments, testing various combinations of food by-products to create bio-polymers. After careful evaluation, it was discovered that eggshells and PLA polymer produced promising results. The initial mixing of the two materials involved heating them just above the melting point. To make the compound 3D printable, the research focused on finding the optimal formulation and production process. The process started with precise measurements of the PLA and eggshell materials. The PLA was placed in a heating oven to remove any absorbed moisture. Handmade testing samples were created to guide the planning for 3D-printed versions. The scrap PLA was recycled and ground into a powdered state. The drying process involved gradual moisture evaporation, which required several hours. The PLA and eggshell materials were then placed into the hopper of a filament-making machine. The machine's four heating elements controlled the temperature of the melted compound mixture, allowing for optimal filament production with accurate and consistent thickness. The filament-making machine extruded the compound, producing filament that could be wound on a wheel. During the testing phase, trials were conducted with different percentages of eggshell in the PLA mixture, including a high percentage (20%). However, poor extrusion results were observed for high eggshell percentage mixtures. Samples were created, and continuous improvement and optimization were pursued to achieve filaments with good performance. To test the 3D printability of the DIY filament, a 3D printer was utilized, set to print the DIY filament smoothly and consistently. Samples were printed and mechanically tested using a universal testing machine to determine their mechanical properties. This testing process allowed for the evaluation of the filament's performance and suitability for additive manufacturing applications. In conclusion, the project explores the creation of a sustainable bio-polymer compound using eggshells and PLA polymer for 3D printing. The research journey involved precise measurements, drying of PLA, and the utilization of a filament-making machine to produce 3D printable filaments. Continuous improvement and optimization were pursued to achieve filaments with good performance. The project's findings contribute to the advancement of additive manufacturing, offering opportunities for design innovation, carbon footprint reduction, supply chain optimization, and collaborative potential. The utilization of eggshell PLA polymer in additive manufacturing has the potential to revolutionize the manufacturing industry, providing a sustainable alternative and enabling the production of intricate and customized products.

Keywords: additive manufacturing, 3D printing, eggshell PLA polymer, design innovation, carbon footprint reduction, supply chain optimization, collaborative potential

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1918 The Interrelations between Niemeyer’s Works and the Concept of Typology: A Computer Based Analysis of Form and Structure

Authors: Aline M. C. Santoro, João C. Pantoja, Eduardo P. Rossetti

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While the aim of the modernist movement was to deny known typology, the creation of a new formal language also gave it new meaning, which was now related to Form. This is specifically true in the modern capital of Brazil, where Niemeyer sought to demonstrate the manner in which the new materials available, such as reinforced concrete, were able to produce innovative forms. With this study, we aim to demonstrate the relationship between Niemeyer’s forms and the topological typology known as tessellation, through the presentation of two case studies, the Monument to Caxias and the Saint George Orthodox Church. At a first glance, our purpose is to present the definition of Form, especially with relationship to the works of Niemeyer, seeking to identify in them the concepts presented by Moussavi. Afterwards, we will use a computer-based approach to study and model the forms of two of his buildings with the McNeel Rhinoceros program, where, with the aid of diagrams and renderings, we will be able to clearly and legibly represent their organic forms and further understand their structural systems. When we recognise the concept of typology as a starting point for structural form, it can be concluded that the case studies presented here are encompassed by the typology presented by Moussavi since they derive from his basic structural systems.

Keywords: form, Niemeyer, structure, typology, topology

Procedia PDF Downloads 198
1917 Women’s Language and Gender Positioning in the Discourse of Indonesian Instagram Videos

Authors: Haira Rizka, Imas Istiani

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The way women and men use language is an interesting topic to discuss. Nowadays, Instagram shows many videos which illustrate the difference of women’s and men’s language. Furthermore, the videos show how different genders behave in daily communication. This research aims to (1) investigate conversational characteristics of women represented in Indonesian Instagram videos, and (2) investigate how different genders behave in daily communication. To analyze the two research problems, this research employs Tannen’s theory of language and gender (1996). This is a descriptive qualitative research which describes phenomena of language and gender shown in Indonesian Instagram videos. The data were collected through observation. The collected data were then analyzed by employing ethnography and textual analysis. The research results show that in Indonesian Instagram videos, women dominate the conversation than men. Women’s are portrayed as a figure who are talkative, never wrong, and sensitive. Women’s dominating men proves that women always want to be understood, produce more words than men, and are more creative in producing verbal communication. Meanwhile, men are portrayed as calm, gentle, and patient creature who listen to women’s talk. Furthermore, men are portrayed to prefer being silent for avoiding conflict.

Keywords: gender, Instagram videos, language variety, women's language

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1916 Nanocharacterization of PIII Treated 7075 Aluminum Alloy

Authors: Bruno Bacci Fernandes, Stephan Mändl, Ataíde Ribeiro da Silva Junior, José Osvaldo Rossi, Mário Ueda

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Nitrogen implantation in aluminum and its alloys is acquainted for the difficulties in obtaining modified layers deeper than 200 nm. The present work addresses a new method to overcome such a problem; although, the coating with nitrogen and oxygen obtained by plasma immersion ion implantation (PIII) into a 7075 aluminum alloy surface was too shallow. This alloy is commonly used for structural parts in aerospace applications. Such a layer was characterized by secondary ion mass spectroscopy, electron microscopy, and nanoindentation experiments reciprocating wear tests. From the results, one can assume that the wear of this aluminum alloy starts presenting severe abrasive wear followed by an additional adhesive mechanism. PIII produced a slight difference, as shown in all characterizations carried out in this work. The results shown here can be used as the scientific basis for further nitrogen PIII experiments in aluminum alloys which have the goal to produce thicker modified layers or to improve their surface properties.

Keywords: aluminum alloys, plasma immersion ion implantation, tribological properties, hardness, nanofatigue

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1915 Flexural Strength Design of RC Beams with Consideration of Strain Gradient Effect

Authors: Mantai Chen, Johnny Ching Ming Ho

Abstract:

The stress-strain relationship of concrete under flexure is one of the essential parameters in assessing ultimate flexural strength capacity of RC beams. Currently, the concrete stress-strain curve in flexure is obtained by incorporating a constant scale-down factor of 0.85 in the uniaxial stress-strain curve. However, it was revealed that strain gradient would improve the maximum concrete stress under flexure and concrete stress-strain curve is strain gradient dependent. Based on the strain-gradient-dependent concrete stress-strain curve, the investigation of the combined effects of strain gradient and concrete strength on flexural strength of RC beams was extended to high strength concrete up to 100 MPa by theoretical analysis. As an extension and application of the authors’ previous study, a new flexural strength design method incorporating the combined effects of strain gradient and concrete strength is developed. A set of equivalent rectangular concrete stress block parameters is proposed and applied to produce a series of design charts showing that the flexural strength of RC beams are improved with strain gradient effect considered.

Keywords: beams, equivalent concrete stress block, flexural strength, strain gradient

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1914 Statistical Analysis of Surface Roughness and Tool Life Using (RSM) in Face Milling

Authors: Mohieddine Benghersallah, Lakhdar Boulanouar, Salim Belhadi

Abstract:

Currently, higher production rate with required quality and low cost is the basic principle in the competitive manufacturing industry. This is mainly achieved by using high cutting speed and feed rates. Elevated temperatures in the cutting zone under these conditions shorten tool life and adversely affect the dimensional accuracy and surface integrity of component. Thus it is necessary to find optimum cutting conditions (cutting speed, feed rate, machining environment, tool material and geometry) that can produce components in accordance with the project and having a relatively high production rate. Response surface methodology is a collection of mathematical and statistical techniques that are useful for modelling and analysis of problems in which a response of interest is influenced by several variables and the objective is to optimize this response. The work presented in this paper examines the effects of cutting parameters (cutting speed, feed rate and depth of cut) on to the surface roughness through the mathematical model developed by using the data gathered from a series of milling experiments performed.

Keywords: Statistical analysis (RSM), Bearing steel, Coating inserts, Tool life, Surface Roughness, End milling.

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1913 Characteristics of Different Volumes of Waste Cellular Concrete Powder-Cement Paste for Sustainable Construction

Authors: Mohammed Abed, Rita Nemes

Abstract:

Cellular concrete powder (CCP) is not used widely as supplementary cementitious material, but in the literature, its efficiency is proved when it used as a replacement of cement in concrete mixtures. In this study, different amounts of raw CCP (CCP as a waste material without any industrial modification) will be used to investigate the characteristics of cement pastes and the effects of CCP on the properties of the cement pastes. It is an attempt to produce green binder paste, which is useful for sustainable construction applications. The fresh and hardened properties of a number of CCP blended cement paste will be tested in different life periods, and the optimized CCP volume will be reported with more significant investigations on durability properties. Different replacing of mass percentage (low and high) of the cement mass will be conducted (0%, 10%, 15%, 20%, 30%, 40%, 50%, 60%, 70%, 80%, and 90%). The consistency, flexural strength, and compressive strength will be the base indicator for the further properties' investigations. The CCP replacement until 50% have been tested until 7 days, and the initial results showed a linear relationship between strength and the percentage of the replacement; that is an optimistic indicator for further replacement percentages of waste CCP.

Keywords: cellular concrete powder, supplementary cementitious material, sustainable construction, green concrete

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1912 Cloud Computing in Data Mining: A Technical Survey

Authors: Ghaemi Reza, Abdollahi Hamid, Dashti Elham

Abstract:

Cloud computing poses a diversity of challenges in data mining operation arising out of the dynamic structure of data distribution as against the use of typical database scenarios in conventional architecture. Due to immense number of users seeking data on daily basis, there is a serious security concerns to cloud providers as well as data providers who put their data on the cloud computing environment. Big data analytics use compute intensive data mining algorithms (Hidden markov, MapReduce parallel programming, Mahot Project, Hadoop distributed file system, K-Means and KMediod, Apriori) that require efficient high performance processors to produce timely results. Data mining algorithms to solve or optimize the model parameters. The challenges that operation has to encounter is the successful transactions to be established with the existing virtual machine environment and the databases to be kept under the control. Several factors have led to the distributed data mining from normal or centralized mining. The approach is as a SaaS which uses multi-agent systems for implementing the different tasks of system. There are still some problems of data mining based on cloud computing, including design and selection of data mining algorithms.

Keywords: cloud computing, data mining, computing models, cloud services

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1911 Corrosion Properties of Friction Welded Dissimilar Aluminum Alloys; Duralumin and AA6063

Authors: Sori Won, Bosung Seo, Kwangsuk Park, Seok Hong Min, Tae Kwon Ha

Abstract:

With the increased needs for lightweight materials in automobile industry, the usage of aluminum alloys becomes prevailed as components and car bodies due to their comparative specific strength. These parts composed of different aluminum alloys should be connected each other, where welding technologies are commonly applied. Among various welding methods, friction welding method as a solid state welding gets to be popular in joining aluminum alloys as it does not produce a defect such as blowhole that is often formed during typical welding processes. Once two metals are joined, corrosion would become an issue due to different electrochemical potentials. In this study, we investigated variations of corrosion properties when Duralumin and AA6063 were joined by friction welding. From the polarization test, it was found that the potential of the welded was placed between those of two original metals, which could be explained by a concept of mixed potential. Pitting is a common form as a result of the corrosion of aluminum alloys when they are exposed to 3.5 wt% NaCl solution. However, when two different aluminum alloys (Duralumin and AA6063) were joined, pitting corrosion occurred severely and uniformly in Duralumin while there were a few pits around precipitates in AA6063, indicating that AA6063 was cathodically protected.

Keywords: corrosion properties, friction welding, dissimilar Al alloys, polarization test

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1910 Microbial Removal of Polycyclic Aromatic Hydrocarbons from Petroleum Refinery Sludge: A Consortial Approach

Authors: Dheepshika Kodieswaran

Abstract:

The persisting problem in the world that continuously impose our planet at risk is the increasing amounts of recalcitrant. One such issue is the disposal of the Petroleum Refinery Sludge (PRS) which constitutes hydrocarbons that are hazardous to terrestrial and aquatic life. The comparatively safe approach to handling these wastes is by microbial degradation, while the other chemical and physical methods are either expensive and/or produce secondary pollutants. The bacterial and algal systems have different pathways for the degradation of hydrocarbons, and their growth rates vary. This study shows how different bacterial and microalgal strains degrade the polyaromatic hydrocarbon PAHs individually and their symbiotic influence on degradation as well. In this system, the metabolites and gaseous exchange help each other in growth. This method using also aids in the accumulation of lipids in microalgal cells and from which bio-oils can also be extracted. The bacterial strains used in this experiment are reported to be indigenous strains isolated from PRS. The target PAH studied were anthracene and pyrene for a period of 28 days. The PAH degradation kinetics best fitted the Gompertz model, and the order of the kinetics, rate constants, and half-life was determined.

Keywords: petroleum refinery sludge, co-culturing, polycyclic hydrocarbons, microalgal-bacterial consortia

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1909 Alcoxysilanes Production from Silica and Dimethylcarbonate Promoted by Alkali Bases: A DFT Investigation of the Reaction Mechanism

Authors: Valeria Butera, Norihisa Fukaya, Jun-Chu Choi, Kazuhiko Sato, Yoong-Kee Choe

Abstract:

Several silicon dioxide sources can react with dimethyl carbonate (DMC) in presence of alkali bases catalysts to ultimately produce tetramethoxysilane (TMOS). Experimental findings suggested that the reaction proceeds through several steps in which the first molecule of DMC is converted to dimethylsilyloxide (DMOS) and CO₂. Following the same mechanistic steps, a second molecule of DMC reacts with the DMOS to afford the final product TMOS. Using a cluster model approach, a quantum-mechanical investigation of the first part of the reaction leading to DMOS formation is reported with a twofold purpose: (1) verify the viability of the reaction mechanism proposed on the basis of experimental evidences .(2) compare the behaviors of three different alkali hydroxides MOH, where M=Li, K and Cs, to determine whether diverse ionic radius and charge density can be considered responsible for the observed differences in reactivity. Our findings confirm the observed experimental trend and furnish important information about the effective role of the alkali hydroxides giving an explanation of the different catalytic activity of the three metal cations.

Keywords: Alcoxysilanes production, cluster model approach, DFT, DMC conversion

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1908 Impact of Radio on Rural Development: A Study of Ipokia Local Government Area, Nigeria

Authors: Haruna Shola Adeosun, Adeoye Odedeji

Abstract:

This paper examines the impact of radio on rural development. The researcher employed survey method to gather primary data. The objectives and questions were used from and hypotheses were formulated were raised from the statement of the problem. Cultivation theory was used as the theoretical study. The populations of the study were the inhabitant of Ipokia Local Government. Questionnaires were administered on the 400 respondents. Data gathered were analyzed, interpreted and hypotheses of the study were tested. The finding revealed that; radio has impacted on the rural dwellers and there is a significant relationship between radio and rural dwellers. Also, radio has brought socio-economic development on rural dwellers. The study recommended that radio messages should be designed in line with the pre-existing attitudes of the rural dwellers. It was also discovered that radio stations should endeavour to use local dialects especially when the radio programme is aimed at the rural dwellers that effective communication that can increase active participation of government and the public. Finally, the study recommends that radio stations should be well funded to produce programmes that would serve the purpose of educating and informing the public on issues relevant to them and there is need to establish community radio stations that will be closer to rural dwellers.

Keywords: impact, radio, rural, development

Procedia PDF Downloads 325