Search results for: selection mechanisms
1514 Grain Growth in Nanocrystalline and Ultra-Fine Grained Materials
Authors: Haiming Wen
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Grain growth is an important and consequential phenomenon that generally occurs in the presence of thermal and/or stress/strain fields. Thermally activated grain growth has been extensively studied and similarly, there are numerous experimental and theoretical studies published describing stress-induced grain growth in single-phase materials. However, studies on grain growth during the simultaneous presence of an elevated temperature and an external stress are very limited, and moreover, grain growth phenomena in materials containing second-phase particles and solute segregation at GBs have received limited attention. This lecture reports on a study of grain growth in the presence of second-phase particles and solute/impurity segregation at grain boundaries (GBs) during high-temperature deformation of an ultra-fine grained (UFG) Al alloy synthesized via consolidation of mechanically milled powders. The mechanisms underlying the grain growth were identified as GB migration and grain rotation, which were accompanied by dynamic recovery and geometric dynamic recrystallization, while discontinuous dynamic recrystallization was not operative. A theoretical framework that incorporates the influence of second-phase particles and solute/impurity segregation at GBs on grain growth in presence of both elevated temperature and external stress is formulated and discussed. The effect of second-phase particles and solute/impurity segregation at GBs on GB migration and grain rotation was quantified using the proposed theoretical framework, indicating that both second-phase particles and solutes/impurities segregated GBs reduce the velocities of GB migration and grain rotation as compared to those in commercially pure Al. Our results suggest that grain growth predicted by the proposed theoretical framework is in agreement with experimental results. Hence, the developed theoretical framework can be applied to quantify grain growth in simultaneous presence of external stress, elevated temperature, GB segregation and second-phase particles, or in presence of one or more of the aforementioned factors.Keywords: nanocrystalline materials, ultra-fine grained materials, grain growth, grain boundary migration, grain rotation
Procedia PDF Downloads 3251513 Altered Gene Expression: Induction/Suppression of some Pathogenesis Related Protein Genes in an Egyptian Isolate of Potato Leafroll Virus (PLRV)
Authors: Dalia G. Aseel
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The potato (Solanum tubersum, L.) has become one of the major vegetable crops in Egypt and all over the world. Potato leafroll virus(PLRV) was observed on potato plants collected from different governorates in Egypt. Three cultivars, Spunta, Diamont, and Cara, infected with PLRV were collected; RNA was extracted and subjected to Real-Time PCR using the coat protein gene primers. The results showed that the expression of the coat protein was 39.6-fold, 12.45-fold, and 47.43-fold, respectively, for Spunta, Diamont, and Cara cultivars. Differential Display Polymerase Chain Reaction (DD-PCR) using pathogenesis-related protein 1 (PR-1), β-1,3-glucanases (PR-2), chitinase (PR-3), peroxidase (POD), and polyphenol oxidase (PPO) forward primers for pathogenesis-related proteins (PR). The obtained data revealed different banding patterns depending on the viral type and the region of infection. Regarding PLRV, 58 up-regulated and 19 down-regulated genes were detected. Sequence analysis of the up-and down-regulated genes revealed that infected plants were observed in comparison with the healthy control. Sequence analysis of the up-regulated gene was performed, and the encoding sequence analysis showed that the obtained genes include: induced stolen tip protein. On the other hand, two down-regulated genes were identified: disease resistance RPP-like protein and non-specific lipid-transfer protein. In this study, the expressions of PR-1, PR-2, PR-3, POD, and PPO genes in the infected leaves of three potato cultivars were estimated by quantitative real-time PCR. We can conclude that the PLRV-infection of potato plants inhibited the expression of the five PR genes. On the contrary, infected leaves by PLRV elevated the expression of some defense genes. This interaction may also induce and/or suppress the expression of some genes responsible for the plant's defense mechanisms.Keywords: PLRV, pathogenesis-related proteins (PRs), DD-PCR, sequence, real-time PCR
Procedia PDF Downloads 1421512 Collagen Deposition in Lung Parenchyma Driven by Depletion of LYVE-1+ Macrophages Protects Emphysema and Loss of Airway Function
Authors: Yinebeb Mezgebu Dagnachew, Hwee Ying Lim, Liao Wupeng, Sheau Yng Lim, Lim Sheng Jie Natalie, Veronique Angeli
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Collagen is essential for maintaining lung structure and function, and its remodeling has been associated with respiratory diseases, including chronic obstructive pulmonary disease (COPD). However, the cellular mechanisms driving collagen remodeling and the functional implications of this process in the pathophysiology of pulmonary diseases remain poorly understood. Using a mouse model of Lyve-1 expressing macrophage depletion, we found that the absence of this subpopulation of tissue-resident macrophage led to the preferential deposition of type I collagen fibers around the alveoli and bronchi in the steady state. Further analysis by polarized light microscopy revealed that the collagen fibers accumulating in the lungs depleted of Lyve-1+ macrophages were thicker and crosslinked. A decrease in MMP-9 gene expression and proteolytic activity, together with an increase in Col1a1, Timp-3 and Lox gene expression, accompanied the collagen alterations. Next, we investigated the effect of the collagen remodeling on the pathophysiology of COPD and airway function in mouse lacking Lyve-1+ macrophage exposed chronically to cigarette smoke (CS), a well-established animal model of COPD. We showed that the deposition of collagen protected mouse against the destruction of alveoli (emphysema) and bronchi thickening after CS exposure and prevented loss of airway function. Thus, we demonstrate that interstitial Lyve-1+ macrophages regulate the composition, amount, and architecture of the collagen network in the lungs and that such collagen remodeling functionally impacts the development of COPD. This study further supports the potential of targeting collagen as a promising approach to treating respiratory diseases.Keywords: lung, extracellular matrix, chronic obstructive pulmonary disease, matrix metalloproteinases, collagen
Procedia PDF Downloads 371511 Review and Analysis of Parkinson's Tremor Genesis Using Mathematical Model
Authors: Pawan Kumar Gupta, Sumana Ghosh
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Parkinson's Disease (PD) is a long-term neurodegenerative movement disorder of the central nervous system with vast symptoms related to the motor system. The common symptoms of PD are tremor, rigidity, bradykinesia/akinesia, and postural instability, but the clinical symptom includes other motor and non‐motor issues. The motor symptoms of the disease are consequence of death of the neurons in a region of the midbrain known as substantia nigra pars compacta, leading to decreased level of a neurotransmitter known as dopamine. The cause of this neuron death is not clearly known but involves formation of Lewy bodies, an abnormal aggregation or clumping of the protein alpha-synuclein in the neurons. Unfortunately, there is no cure for PD, and the management of this disease is challenging. Therefore, it is critical for a patient to be diagnosed at early stages. A limited choice of drugs is available to improve the symptoms, but those become less and less effective over time. Apart from that, with rapid growth in the field of science and technology, other methods such as multi-area brain stimulation are used to treat patients. In order to develop advanced techniques and to support drug development for treating PD patients, an accurate mathematical model is needed to explain the underlying relationship of dopamine secretion in the brain with the hand tremors. There has been a lot of effort in the past few decades on modeling PD tremors and treatment effects from a computational point of view. These models can effectively save time as well as the cost of drug development for the pharmaceutical industry and be helpful for selecting appropriate treatment mechanisms among all possible options. In this review paper, an effort is made to investigate studies on PD modeling and analysis and to highlight some of the key advances in the field over the past centuries with discussion on the current challenges.Keywords: Parkinson's disease, deep brain stimulation, tremor, modeling
Procedia PDF Downloads 1401510 The Impact of Model Specification Decisions on the Teacher ValuE-added Effectiveness: Choosing the Correct Predictors
Authors: Ismail Aslantas
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Value-Added Models (VAMs), the statistical methods for evaluating the effectiveness of teachers and schools based on student achievement growth, has attracted decision-makers’ and researchers’ attention over the last decades. As a result of this attention, many studies have conducted in recent years to discuss these statistical models from different aspects. This research focused on the importance of conceptual variables in VAM estimations; therefor, this research was undertaken to examine the extent to which value-added effectiveness estimates for teachers can be affected by using context predictions. Using longitudinal data over three years from the international school context, value-added teacher effectiveness was estimated by ordinary least-square value-added models, and the effectiveness of the teachers was examined. The longitudinal dataset in this study consisted of three major sources: students’ attainment scores up to three years and their characteristics, teacher background information, and school characteristics. A total of 1,027 teachers and their 35,355 students who were in eighth grade were examined for understanding the impact of model specifications on the value-added teacher effectiveness evaluation. Models were created using selection methods that adding a predictor on each step, then removing it and adding another one on a subsequent step and evaluating changes in model fit was checked by reviewing changes in R² values. Cohen’s effect size statistics were also employed in order to find out the degree of the relationship between teacher characteristics and their effectiveness. Overall, the results indicated that prior attainment score is the most powerful predictor of the current attainment score. 47.1 percent of the variation in grade 8 math score can be explained by the prior attainment score in grade 7. The research findings raise issues to be considered in VAM implementations for teacher evaluations and make suggestions to researchers and practitioners.Keywords: model specification, teacher effectiveness, teacher performance evaluation, value-added model
Procedia PDF Downloads 1351509 Induction of Adaptive Response in Yeast Cells under Influence of Extremely High Frequency Electromagnetic Field
Authors: Sergei Voychuk
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Introduction: Adaptive response (AR) is a manifestation of radiation hormesis, which deal with the radiation resistance that may be increased with the pretreatment with small doses of radiation. In the current study, we evaluated the potency of radiofrequency EMF to induce the AR mechanisms and to increase a resistance to UV light. Methods: Saccharomyces cerevisiae yeast strains, which were created to study induction of mutagenesis and recombination, were used in the study. The strains have mutations in rad2 and rad54 genes, responsible for DNA repair: nucleotide excision repair (PG-61), postreplication repair (PG-80) and mitotic (crossover) recombination (T2). An induction of mutation and recombination are revealed due to the formation of red colonies on agar plates. The PG-61 and T2 are UV sensitive strains, while PG-80 is sensitive to ionizing radiation. Extremely high frequency electromagnetic field (EHF-EMF) was used. The irradiation was performed in floating mode and frequency changed during exposure from 57 GHz to 62 GHz. The power of irradiation was 100 mkW, and duration of exposure was 10 and 30 min. Treatment was performed at RT and then cells were stored at 28° C during 1 h without any exposure but after that they were treated with UV light (254nm) for 20 sec (strain T2) and 120 sec (strain PG-61 and PG-80). Cell viability and quantity of red colonies were determined after 5 days of cultivation on agar plates. Results: It was determined that EHF-EMF caused 10-20% decrease of viability of T2 and PG-61 strains, while UV showed twice stronger effect (30-70%). EHF-EMF pretreatment increased T2 resistance to UV, and decreased it in PG-61. The PG-80 strain was insensitive to EHF-EMF and no AR effect was determined for this strain. It was not marked any induction of red colonies formation in T2 and PG-80 strain after EHF or UV exposure. The quantity of red colonies was 2 times more in PG-61 strain after EHF-EMF treatment and at least 300 times more after UV exposure. The pretreatment of PG-61 with EHF-EMF caused at least twice increase of viability and consequent decrease of amount of red colonies. Conclusion: EHF-EMF may induce AR in yeast cells and increase their viability under UV treatment.Keywords: Saccharomyces cerevisiae, EHF-EMF, UV light, adaptive response
Procedia PDF Downloads 3201508 Land Management Framework: A Case of Kolkata
Authors: Alokananda Nath
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Land is an important issue anywhere in the world as it is one of the fundamental elements in human settlements. Since the urban areas are considered to be the drivers of economy for any country across the world and the phenomenon of ‘urbanization’ happening everywhere, there is always a greater pressure on urban land and its management. Many states in India have realized the importance of land as a valuable resource and have implemented certain framework for managing and developing land. But in West Bengal no such statutory framework has been formulated till now and a very out dated model of land acquisition for public purpose is practiced. Due to the lop-sided character of urban growth in the entire eastern region of India, the city of Kolkata continues to bear the burden of excessive growth of population and consequent urbanization of the adjoining areas at a rapid pace. This research tries to look into these conflicts with respect to the present pattern of development in the context of Kolkata and suggest a system for land management in order to implement the planning processes. For this purpose, five case study areas were taken up within the Kolkata Metropolitan Area and subsequent analysis of their present land management and development techniques was done. The findings reveal that there is a lack of political will as well as administrative inefficiency on part of both the development authority and the local bodies. Mostly the local bodies lack the financial resources and technical expertise to work out any kind of land management framework or work out any kind of model in order to manage the development that is happening. All these place undue strain on city infrastructure systems and reduce the potential of cities to contribute as engines of economic growth. The focus of reforms, therefore, ought to be on streamlining the urban planning process, judicious and optimal land use, efficient plan implementation mechanisms, improvement of titling and registration processes.Keywords: urbanization, land management framework, land development, policy reforms, land-use planning processes
Procedia PDF Downloads 2781507 Analysis of NMDA Receptor 2B Subunit Gene (GRIN2B) mRNA Expression in the Peripheral Blood Mononuclear Cells of Alzheimer's Disease Patients
Authors: Ali̇ Bayram, Semih Dalkilic, Remzi Yigiter
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N-methyl-D-aspartate (NMDA) receptor is a subtype of glutamate receptor and plays a pivotal role in learning, memory, neuronal plasticity, neurotoxicity and synaptic mechanisms. Animal experiments were suggested that glutamate-induced excitotoxic injuriy and NMDA receptor blockage lead to amnesia and other neurodegenerative diseases including Alzheimer’s disease (AD), Huntington’s disease, amyotrophic lateral sclerosis. Aim of this study is to investigate association between NMDA receptor coding gene GRIN2B expression level and Alzheimer disease. The study was approved by the local ethics committees, and it was conducted according to the principles of the Declaration of Helsinki and guidelines for the Good Clinical Practice. Peripheral blood was collected 50 patients who diagnosed AD and 49 healthy control individuals. Total RNA was isolated with RNeasy midi kit (Qiagen) according to manufacturer’s instructions. After checked RNA quality and quantity with spectrophotometer, GRIN2B expression levels were detected by quantitative real time PCR (QRT-PCR). Statistical analyses were performed, variance between two groups were compared with Mann Whitney U test in GraphpadInstat algorithm with 95 % confidence interval and p < 0.05. After statistical analyses, we have determined that GRIN2B expression levels were down regulated in AD patients group with respect to control group. But expression level of this gene in each group was showed high variability. İn this study, we have determined that NMDA receptor coding gene GRIN2B expression level was down regulated in AD patients when compared with healthy control individuals. According to our results, we have speculated that GRIN2B expression level was associated with AD. But it is necessary to validate these results with bigger sample size.Keywords: Alzheimer’s disease, N-methyl-d-aspartate receptor, NR2B, GRIN2B, mRNA expression, RT-PCR
Procedia PDF Downloads 3941506 Design and Analysis of Hybrid Morphing Smart Wing for Unmanned Aerial Vehicles
Authors: Chetan Gupta, Ramesh Gupta
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Unmanned aerial vehicles, of all sizes, are prime targets of the wing morphing concept as their lightweight structures demand high aerodynamic stability while traversing unsteady atmospheric conditions. In this research study, a hybrid morphing technology is developed to aid the trailing edge of the aircraft wing to alter its camber as a monolithic element rather than functioning as conventional appendages like flaps. Kinematic tailoring, actuation techniques involving shape memory alloys (SMA), piezoelectrics – individually fall short of providing a simplistic solution to the conundrum of morphing aircraft wings. On the other hand, the feature of negligible hysteresis while actuating using compliant mechanisms has shown higher levels of applicability and deliverability in morphing wings of even large aircrafts. This research paper delves into designing a wing section model with a periodic, multi-stable compliant structure requiring lower orders of topological optimization. The design is sub-divided into three smaller domains with external hyperelastic connections to achieve deflections ranging from -15° to +15° at the trailing edge of the wing. To facilitate this functioning, a hybrid actuation system by combining the larger bandwidth feature of piezoelectric macro-fibre composites and relatively higher work densities of shape memory alloy wires are used. Finite element analysis is applied to optimize piezoelectric actuation of the internal compliant structure. A coupled fluid-surface interaction analysis is conducted on the wing section during morphing to study the development of the velocity boundary layer at low Reynold’s numbers of airflow.Keywords: compliant mechanism, hybrid morphing, piezoelectrics, shape memory alloys
Procedia PDF Downloads 3121505 Influence of Processing Parameters in Selective Laser Melting on the Microstructure and Mechanical Properties of Ti/Tin Composites With in-situ and ex-situ Reinforcement
Authors: C. Sánchez de Rojas Candela, A. Riquelme, P. Rodrigo, M. D. Escalera-Rodríguez, B. Torres, J. Rams
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Selective laser melting is one of the most commonly used AM techniques. In it, a thin layer of metallic powder is deposited, and a laser is used to melt selected zones. The accumulation of layers, each one molten in the preselected zones, gives rise to the formation of a 3D sample with a nearly arbitrary design. To ensure that the properties of the final parts match those of the powder, all the process is carried out in an inert atmosphere, preferentially Ar, although this gas could be substituted. Ti6Al4V alloy is widely used in multiple industrial applications such as aerospace, maritime transport and biomedical, due to its properties. However, due to the demanding requirements of these applications, greater hardness and wear resistance are necessary, together with a better machining capacity, which currently limits its commercialization. To improve these properties, in this study, Selective Laser Melting (SLM) is used to manufacture Ti/TiN metal matrix composites with in-situ and ex-situ titanium nitride reinforcement where the scanning speed is modified (from 28.5 up to 65 mm/s) to study the influence of the processing parameters in SLM. A one-step method of nitriding the Ti6Al4V alloy is carried out to create in-situ TiN reinforcement in a reactive atmosphere and it is compared with ex-situ composites manufactured by previous mixture of both the titanium alloy powder and the ceramic reinforcement particles. The microstructure and mechanical properties of the different Ti/TiN composite materials have been analyzed. As a result, the existence of a similar matrix has been confirmed in in-situ and ex-situ fabrications and the growth mechanisms of the nitrides have been studied. An increase in the mechanical properties with respect to the initial alloy has been observed in both cases and related to changes in their microstructure. Specifically, a greater improvement (around 30.65%) has been identified in those manufactured by the in-situ method at low speeds although other properties such as porosity must be improved for their future industrial applicability.Keywords: in-situ reinforcement, nitriding reaction, selective laser melting, titanium nitride
Procedia PDF Downloads 791504 The Growth of E-Commerce and Online Dispute Resolution in Developing Nations: An Analysis
Authors: Robin V. Cupido
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Online dispute resolution has been identified in many countries as a viable alternative for resolving conflicts which have arisen in the so-called digital age. This system of dispute resolution is developing alongside the Internet, and as new types of transactions are made possible by our increased connectivity, new ways of resolving disputes must be explored. Developed nations, such as the United States of America and the European Union, have been involved in creating these online dispute resolution mechanisms from the outset, and currently have sophisticated systems in place to deal with conflicts arising in a number of different fields, such as e-commerce, domain name disputes, labour disputes and conflicts arising from family law. Specifically, in the field of e-commerce, the Internet’s borderless nature has served as a way to promote cross-border trade, and has created a global marketplace. Participation in this marketplace boosts a country’s economy, as new markets are now available, and consumers can transact from anywhere in the world. It would be especially advantageous for developing nations to be a part of this global marketplace, as it could stimulate much-needed investment in these nations, and encourage international co-operation and trade. However, for these types of transactions to proliferate, an effective system for resolving the inevitable disputes arising from such an increase in e-commerce is needed. Online dispute resolution scholarship and practice is flourishing in developed nations, and it is clear that the gap is widening between developed and developing nations in this regard. The potential for implementing online dispute resolution in developing countries has been discussed, but there are a number of obstacles that have thus far prevented its continued development. This paper aims to evaluate the various political, infrastructural and socio-economic challenges faced in developing nations, and to question how these have impacted the acceptance and development of online dispute resolution, scholarship and training of online dispute resolution practitioners and, ultimately, developing nations’ readiness to participate in cross-border e-commerce.Keywords: developing countries, feasibility, online dispute resolution, progress
Procedia PDF Downloads 3021503 A Structuring and Classification Method for Assigning Application Areas to Suitable Digital Factory Models
Authors: R. Hellmuth
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The method of factory planning has changed a lot, especially when it is about planning the factory building itself. Factory planning has the task of designing products, plants, processes, organization, areas, and the building of a factory. Regular restructuring is becoming more important in order to maintain the competitiveness of a factory. Restrictions in new areas, shorter life cycles of product and production technology as well as a VUCA world (Volatility, Uncertainty, Complexity and Ambiguity) lead to more frequent restructuring measures within a factory. A digital factory model is the planning basis for rebuilding measures and becomes an indispensable tool. Furthermore, digital building models are increasingly being used in factories to support facility management and manufacturing processes. The main research question of this paper is, therefore: What kind of digital factory model is suitable for the different areas of application during the operation of a factory? First, different types of digital factory models are investigated, and their properties and usabilities for use cases are analysed. Within the scope of investigation are point cloud models, building information models, photogrammetry models, and these enriched with sensor data are examined. It is investigated which digital models allow a simple integration of sensor data and where the differences are. Subsequently, possible application areas of digital factory models are determined by means of a survey and the respective digital factory models are assigned to the application areas. Finally, an application case from maintenance is selected and implemented with the help of the appropriate digital factory model. It is shown how a completely digitalized maintenance process can be supported by a digital factory model by providing information. Among other purposes, the digital factory model is used for indoor navigation, information provision, and display of sensor data. In summary, the paper shows a structuring of digital factory models that concentrates on the geometric representation of a factory building and its technical facilities. A practical application case is shown and implemented. Thus, the systematic selection of digital factory models with the corresponding application cases is evaluated.Keywords: building information modeling, digital factory model, factory planning, maintenance
Procedia PDF Downloads 1101502 An Attentional Bi-Stream Sequence Learner (AttBiSeL) for Credit Card Fraud Detection
Authors: Amir Shahab Shahabi, Mohsen Hasirian
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Modern societies, marked by expansive Internet connectivity and the rise of e-commerce, are now integrated with digital platforms at an unprecedented level. The efficiency, speed, and accessibility of e-commerce have garnered a substantial consumer base. Against this backdrop, electronic banking has undergone rapid proliferation within the realm of online activities. However, this growth has inadvertently given rise to an environment conducive to illicit activities, notably electronic payment fraud, posing a formidable challenge to the domain of electronic banking. A pivotal role in upholding the integrity of electronic commerce and business transactions is played by electronic fraud detection, particularly in the context of credit cards which underscores the imperative of comprehensive research in this field. To this end, our study introduces an Attentional Bi-Stream Sequence Learner (AttBiSeL) framework that leverages attention mechanisms and recurrent networks. By incorporating bidirectional recurrent layers, specifically bidirectional Long Short-Term Memory (LSTM) and Gated Recurrent Unit (GRU) layers, the proposed model adeptly extracts past and future transaction sequences while accounting for the temporal flow of information in both directions. Moreover, the integration of an attention mechanism accentuates specific transactions to varying degrees, as manifested in the output of the recurrent networks. The effectiveness of the proposed approach in automatic credit card fraud classification is evaluated on the European Cardholders' Fraud Dataset. Empirical results validate that the hybrid architectural paradigm presented in this study yields enhanced accuracy compared to previous studies.Keywords: credit card fraud, deep learning, attention mechanism, recurrent neural networks
Procedia PDF Downloads 181501 In-Situ Studies of Cyclohexane Oxidation Using Laser Raman Spectroscopy for the Refinement of Mechanism Based Kinetic Models
Authors: Christine Fräulin, Daniela Schurr, Hamed Shahidi Rad, Gerrit Waters, Günter Rinke, Roland Dittmeyer, Michael Nilles
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The reaction mechanisms of many liquid-phase reactions in organic chemistry have not yet been sufficiently clarified. Process conditions of several hundred degrees celsius and pressures to ten megapascals complicate the sampling and the determination of kinetic data. Space resolved in-situ measurements promises new insights. A non-invasive in-situ measurement technique has the advantages that no sample preparation is necessary, there is no change in sample mixture before analysis and the sampling do no lead to interventions in the flow. Thus, the goal of our research was the development of a contact-free spatially resolved measurement technique for kinetic studies of liquid phase reaction under process conditions. Therefore we used laser Raman spectroscopy combined with an optical transparent microchannel reactor. To show the performance of the system we choose the oxidation of cyclohexane as sample reaction. Cyclohexane oxidation is an economically important process. The products are intermediates for caprolactam and adipic acid, which are starting materials for polyamide 6 and 6.6 production. To maintain high selectivities of 70 to 90 %, the reaction is performed in industry at a low conversion of about six percent. As Raman spectroscopy is usually very selective but not very sensitive the detection of the small product concentration in cyclohexane oxidation is quite challenging. To meet these requirements, an optical experimental setup was optimized to determine the concentrations by laser Raman spectroscopy with respect to good detection sensitivity. With this measurement technique space resolved kinetic studies of uncatalysed and homogeneous catalyzed cyclohexane oxidation were carried out to obtain details about the reaction mechanism.Keywords: in-situ laser raman spectroscopy, space resolved kinetic measurements, homogeneous catalysis, chemistry
Procedia PDF Downloads 3351500 Indigenous Understandings of Climate Vulnerability in Chile: A Qualitative Approach
Authors: Rosario Carmona
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This article aims to discuss the importance of indigenous people participation in climate change mitigation and adaptation. Specifically, it analyses different understandings of climate vulnerability among diverse actors involved in climate change policies in Chile: indigenous people, state officials, and academics. These data were collected through participant observation and interviews conducted during October 2017 and January 2019 in Chile. Following Karen O’Brien, there are two types of vulnerability, outcome vulnerability and contextual vulnerability. How vulnerability to climate change is understood determines the approach, which actors are involved and which knowledge is considered to address it. Because climate change is a very complex phenomenon, it is necessary to transform the institutions and their responses. To do so, it is fundamental to consider these two perspectives and different types of knowledge, particularly those of the most vulnerable, such as indigenous people. For centuries and thanks to a long coexistence with the environment, indigenous societies have elaborated coping strategies, and some of them are already adapting to climate change. Indigenous people from Chile are not an exception. But, indigenous people tend to be excluded from decision-making processes. And indigenous knowledge is frequently seen as subjective and arbitrary in relation to science. Nevertheless, last years indigenous knowledge has gained particular relevance in the academic world, and indigenous actors are getting prominence in international negotiations. There are some mechanisms that promote their participation (e.g., Cancun safeguards, World Bank operational policies, REDD+), which are not absent from difficulties. And since 2016 parties are working on a Local Communities and Indigenous Peoples Platform. This paper also explores the incidence of this process in Chile. Although there is progress in the participation of indigenous people, this participation responds to the operational policies of the funding agencies and not to a real commitment of the state with this sector. The State of Chile omits a review of the structure that promotes inequality and the exclusion of indigenous people. In this way, climate change policies could be configured as a new mechanism of coloniality that validates a single type of knowledge and leads to new territorial control strategies, which increases vulnerability.Keywords: indigenous knowledge, climate change, vulnerability, Chile
Procedia PDF Downloads 1261499 Combination of Diane-35 and Metformin to Treat Early Endometrial Carcinoma in PCOS Women with Insulin Resistance
Authors: Xin Li, Yan-Rong Guo, Jin-Fang Lin, Yi Feng, Håkan Billig, Ruijin Shao
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Background: Young women with polycystic ovary syndrome (PCOS) have a high risk of developing endometrial carcinoma. There is a need for the development of new medical therapies that can reduce the need for surgical intervention so as to preserve the fertility of these patients. The aim of the study was to describe and discuss cases of PCOS and insulin resistance (IR) women with early endometrial carcinoma while being co-treated with Diane-35 and metformin. Methods: Five PCOS-IR women who were scheduled for diagnosis and therapy for early endometrial carcinoma were recruited. The hospital records and endometrial pathology reports were reviewed. All patients were co-treated with Diane-35 and metformin for 6 months to reverse the endometrial carcinoma and preserve their fertility. Before, during, and after treatment, endometrial biopsies and blood samples were obtained and oral glucose tolerance tests were performed. Endometrial pathology was evaluated. Body weight (BW), body mass index (BMI), follicle-stimulating hormone (FSH), luteinizing hormone (LH), total testosterone (TT), sex hormone-binding globulin (SHBG), free androgen index (FAI), insulin area under curve (IAUC), and homeostasis model assessment of insulin resistance (HOMA-IR) were determined. Results: Clinical stage 1a, low grade endometrial carcinoma was confirmed before treatment. After 6 months of co-treatment, all patients showed normal epithelia. No evidence of atypical hyperplasia or endometrial carcinoma was found. Co-treatment resulted in significant decreases in BW, BMI, TT, FAI, IAUC, and HOMA-IR in parallel with a significant increase in SHBG. There were no differences in the FSH and LH levels after co-treatment. Conclusions: Combined treatment with Diane-35 and metformin has the potential to revert the endometrial carcinoma into normal endometrial cells in PCOS-IR women. The cellular and molecular mechanisms behind this effect merit further investigation.Keywords: PCOS, progesterone resistance, insulin resistance, steroid hormone receptors, endometrial carcinoma
Procedia PDF Downloads 4091498 Impact of Gold Mining on Crop Production, Livelihood and Environmental Sustainability in West Africa in the Context of Water-Energy-Food Nexus
Authors: Yusif Habib
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The Volta River Basin (VRB) is a transboundary resource shared by Six (6) the West African States. It’s utilization spans across irrigation, hydropower generation, domestic/household water use, transportation, industrial processing, among others. Simultaneously, mineral resources such as gold are mined within the VRB catchment. Typically, the extraction/mining operation is earth-surface excavation; known as Artisanal and Small-scale mining. We developed a conceptual framework in the context of Water-Energy-Food (WEF) Nexus to delineate the trade-offs and synergies between the mineral extractive operation’s impact on Agricultural systems, specifically, cereal crops (e.g. Maize, Millet, and Rice) and the environment (water and soil quality, deforestation, etc.) on the VRB. Thus, the study examined the trade-offs and synergies through the WEF nexus lens to explore the extent of an eventual overarching mining preference for gold exploration with high economic returns as opposed to the presumably low yearly harvest and household income from food crops production to inform intervention prioritization. Field survey (household, expert, and stakeholder consultation), bibliometric analysis/literature review, scenario, and simulation models, including land-use land cover (LULC) analyses, were conducted. The selected study area(s) in Ghana was the location where the mineral extractive operation’s presence and impact are widespread co-exist with the Agricultural systems. Overall, the study proposes mechanisms of the virtuous cycle through FEW Nexus instead of the presumably existing vicious cycle to inform decision making and policy implementation.Keywords: agriculture, environmental sustainability, gold Mining, synergies, trade-off, water-energy-food nexus
Procedia PDF Downloads 1631497 Investigating the Flavin-Dependent Thymidylate Synthase (FDTS) Enzyme from Clostridioides Difficile (C. diff)
Authors: Sidra Shaw, Sarenna Shaw, Chae Joon Lee, Irimpan Mathews, Eric Koehn
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One of the biggest public health concerns of our time is increasing antimicrobial resistance. As of 2019, the CDC has documented more than 2.8 million serious antibiotic resistant infections in the United States. Currently, antibiotic resistant infections are directly implicated in over 750,000 deaths per year globally. On our current trajectory, British economist Jim O’Neill predicts that by 2050, an additional 10 million people (about half the population of New York) will die annually due to drug resistant infections. As a result, new biochemical pathways must be targeted to generate next generation antibiotic drugs that will be effective against drug resistant bacteria. One enticing target is the biosynthesis of DNA within bacteria, as few drugs interrupt this essential life process. Thymidylate synthase enzymes are essential for life as they catalyze the synthesis of a DNA building block, 2′-deoxythymidine-5′-monophosphate (dTMP). In humans, the thymidylate synthase enzyme (TSase) has been shown to be distinct from the flavin-dependent thymidylate synthase (FDTS) produced by many pathogenic bacteria. TSase and FDTS have distinct structures and mechanisms of catalysis, which should allow selective inhibition of FDTS over human TSase. Currently, C. diff is one of the most antibiotic resistant bacteria, and no drugs that target thymine biosynthesis exist for C. diff. Here we present the initial biochemical characterization of FDTS from C. diff. Specifically, we examine enzyme kinetics and binding features of this enzyme to determine the nature of interaction with ligands/inhibitors and understand the molecular mechanism of catalysis. This research will provide more insight into the targetability of the C. diff FDTS enzyme for novel antibiotic drugs.Keywords: flavin-dependent thymidylate synthase, FDTS, clostridioides difficile, C. diff, antibiotic resistance, DNA synthesis, enzyme kinetics, binding features
Procedia PDF Downloads 1041496 Structural and Functional Characterization of the Transcriptional Regulator Rv1176 of Mycobacterium tuberculosis H37Rv
Authors: Vikash Yadav, Ashish Arora
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Microorganisms have self-defense mechanisms to protect themselves from toxic environments. Phenolic acid decarboxylase(pad) is responsible for the defense against toxicity caused by phenolic acids, converting them into less toxic vinyl derivatives. The transcription of the pad gene is regulated by a negative transcription factor, phenolic acid decarboxylase regulators (PadR), in a substrate-inducible manner. The PadR family members share the conserved DNA-binding features and interact with the operator DNA using a winged helix-turn-helix (wHTH) motif, which contains a three-helix motif and a β-stranded wing. The members of this family function as transcriptional regulators that are involved in various cellular survival processes, such as toxin production, detoxification, multidrug resistance, antibiotic biosynthesis, and carbon catabolism. Rv1176 of Mycobacterium tuberculosis H37Rv has been assigned to the PadR family protein that remains to be structurally and functionally uncharacterized. To reveal the structural mechanism by which Rv1176 could regulates effector-responsive transcription, several experiments were performed, including Electrophoretic Mobility Shift Assay (EMSA) for DNA protein interaction, differential scanning calorimetry (DSC) and Differential Scanning Fluorimetry (DSF) for temperature and ligand-dependent protein stability, Circular Dichroism (CD) spectroscopy for secondary structure analysis. Further, to evaluate the functional role of Rv1176, the intracellular survival of recombinant M. smegmatis was examined in murine macrophage cell line J774A.1 and different stressed conditions like oxidative, pH, and nutritive stress. All these studies demonstrated that Rv1176 could behave as a transcription regulator and its expression in recombinant M. smegmatis increases intracellular survival.Keywords: EMSA, Mycobacterium tuberculosis, PadR family protein, transcriptional regulator
Procedia PDF Downloads 791495 A Study on the Construction Process and Sustainable Renewal Development of High-Rise Residential Areas in Chongqing (1978-2023)
Authors: Xiaoting Jing, Ling Huang
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After the reform and opening up, Chongqing has formed far more high-rise residential areas than other cities in its more than 40 years of urban construction. High-rise residential areas have become one of the main modern living models in Chongqing and an important carrier reflecting the city's high quality of life. Reviewing the construction process and renewal work helps understand the characteristics of high-rise residential areas in Chongqing at different stages, clarify current development demands, and look forward to the focus of future renewal work. Based on socio-economic development and policy background, the article sorts the construction process of high-rise residential areas in Chongqing into four stages: the early experimental construction period of high-rise residential areas (1978-1996), the rapid start-up period of high-rise commodity housing construction (1997-2006), the large-scale construction period of high-rise commodity housing and public rental housing (2007-2014), and the period of renewal and renovation of high-rise residential areas and step-by-step construction of quality commodity housing (2015-present). Based on the construction demands and main construction types of each stage, the article summarizes that the construction of high-rise residential areas in Chongqing features large scale, high speed, and high density. It points out that a large number of high-rise residential areas built after 2000 will become important objects of renewal and renovation in the future. Based on existing renewal work experience, it is urgent to explore a path for sustainable renewal and development in terms of policy mechanisms, digital supervision, and renewal and renovation models, leading the high-rise living in Chongqing toward high-quality development.Keywords: high-rise residential areas, construction process, renewal and renovation, Chongqing
Procedia PDF Downloads 681494 Anti-Parasite Targeting with Amino Acid-Capped Nanoparticles Modulates Multiple Cellular Processes in Host
Authors: Oluyomi Stephen Adeyemi, Kentaro Kato
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Toxoplasma gondii is the etiological agent of toxoplasmosis, a common parasitic disease capable of infecting a range of hosts, including nearly one-third of the human population. Current treatment options for toxoplasmosis patients are limited. In consequence, toxoplasmosis represents a large global burden that is further enhanced by the shortcomings of the current therapeutic options. These factors underscore the need for better anti-T. gondii agents and/or new treatment approach. In the present study, we sought to find out whether preparing and capping nanoparticles (NPs) in amino acids, would enhance specificity toward the parasite versus the host cell. The selection of amino acids was premised on the fact that T. gondii is auxotrophic for some amino acids. The amino acid-nanoparticles (amino-NPs) were synthesized, purified and characterized following established protocols. Next, we tested to determine the anti-T. gondii activity of the amino-NPs using in vitro experimental model of infection. Overall, our data show evidence that supports enhanced and excellent selective action against the parasite versus the host cells by amino-NPs. The findings are promising and provide additional support that warrants exploring the prospects of NPs as alternative anti-parasite agents. In addition, the anti-parasite action by amino-NPs indicates that nutritional requirement of parasite may represent a viable target in the development of better alternative anti-parasite agents. Furthermore, data suggest the anti-parasite mechanism of the amino-NPs involves multiple cellular processes including the production of reactive oxygen species (ROS), modulation of hypoxia-inducing factor-1 alpha (HIF-1α) as well as the activation of kynurenine pathway. Taken together, findings highlight further, the prospects of NPs as alternative source of anti-parasite agents.Keywords: drug discovery, infectious diseases, mode of action, nanomedicine
Procedia PDF Downloads 1121493 Trends of Cancer Patients Who Underwent Curative/radical Radiotherapy at Radiotherapy Center, Tikur Anbessa Specialized Hospital
Authors: Emeshaw Damtew Zebene, Edom Seife, Hagos Tesfay, Gurja Belay
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Background: cancer incidence and mortality has grown rapidly throughout the world. Aging of the population, urbanization, physical inactivity, economic growth followed by smoking and drinking contributed a lot for the increased incidence of cancer all over the globe. Objective: the aim of this study was to assess a one-year trend of cancer patients who underwent curative/radical radiotherapy at radiotherapy center, Tikur Anbessa specialized hospital, Ethiopia. Methodology: We performed a prospective descriptive study of cancer patients treated with LINAC at Tikur Anbessa specialized hospital, Addis Ababa, Ethiopia, from April 2021- March 2022. A standardized questionnaire was used to collect sociodemographic and clinical characteristics of the patients. Descriptive statistics and chi-square results were generated using SPSS version 24. The level of significance was obtained at 0.05. Results: Sixty-four (64) curative/radical patients-44 females and 20 males were analyzed. Majority, 27(42.2%), of the patients age range from 45 to 64, and 45(70%) of them were urban residents where a group of higher gynecologic cancer was observed.78% of the patients were with locally advanced cancer, and 54(84.4%) of them had no awareness about cancer. Generally, head & neck cancer were found the most prevalent cancer 20(31.3%), and the leading cause of cancer among women was cervical cancer 17(38.6%), where about half 7(15.9%) of them were HIV positive. Conclusion: Our finding revealed that most of curative/radical patients presented at a locally advanced stage of the disease. Hence, maintaining the already available teletherapy machines and installing additional radiotherapy centers may help in treating the patients at the early stage of the disease. Since almost all of our study participants did not have information about cancer, awareness raising mechanisms should be done. Additionally, understanding differences in cancer incidence between urban and rural is important. Key words: Cancer, Curative/radical, Radiotherapy, Tikur Anbessa Specialized HospitalKeywords: cancer, curative/radical, radiotherapy, tkur anbessa specialized hospital
Procedia PDF Downloads 851492 Investigation of Scaling Laws for Stiffness and strength in Bioinspired Glass Sponge Structures Produced by Fused Filament Fabrication
Authors: Hassan Beigi Rizi, Harold Auradou, Lamine Hattali
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Various industries, including civil engineering, automotive, aerospace, and biomedical fields, are currently seeking novel and innovative high-performance lightweight materials to reduce energy consumption. Inspired by the structure of Euplectella Aspergillum Glass Sponges (EA-sponge), 2D unit cells were created and fabricated using a Fused Filament Fabrication (FFF) process with Polylactic acid (PLA) filaments. The stiffness and strength of bio-inspired EA-sponge lattices were investigated both experimentally and numerically under uniaxial tensile loading and are compared to three standard square lattices with diagonal struts (Designs B and C) and non-diagonal struts (Design D) reinforcements. The aim is to establish predictive scaling laws models and examine the deformation mechanisms involved. The results indicated that for the EA-sponge structure, the relative moduli and yield strength scaled linearly with relative density, suggesting that the deformation mechanism is stretching-dominated. The Finite element analysis (FEA), with periodic boundary conditions for volumetric homogenization, confirms these trends and goes beyond the experimental limits imposed by the FFF printing process. Therefore, the stretching-dominated behavior, investigated from 0.1 to 0.5 relative density, demonstrate that the study of EA-sponge structure can be exploited for the realization of square lattice topologies that are stiff and strong and have attractive potential for lightweight structural applications. However, the FFF process introduces an accuracy limitation, with approximately 10% error, making it challenging to print structures with a relative density below 0.2. Future work could focus on exploring the impact of different printing materials on the performance of EA-sponge structures.Keywords: bio-inspiration, lattice structures, fused filament fabrication, scaling laws
Procedia PDF Downloads 71491 A Deep Learning Approach to Real Time and Robust Vehicular Traffic Prediction
Authors: Bikis Muhammed, Sehra Sedigh Sarvestani, Ali R. Hurson, Lasanthi Gamage
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Vehicular traffic events have overly complex spatial correlations and temporal interdependencies and are also influenced by environmental events such as weather conditions. To capture these spatial and temporal interdependencies and make more realistic vehicular traffic predictions, graph neural networks (GNN) based traffic prediction models have been extensively utilized due to their capability of capturing non-Euclidean spatial correlation very effectively. However, most of the already existing GNN-based traffic prediction models have some limitations during learning complex and dynamic spatial and temporal patterns due to the following missing factors. First, most GNN-based traffic prediction models have used static distance or sometimes haversine distance mechanisms between spatially separated traffic observations to estimate spatial correlation. Secondly, most GNN-based traffic prediction models have not incorporated environmental events that have a major impact on the normal traffic states. Finally, most of the GNN-based models did not use an attention mechanism to focus on only important traffic observations. The objective of this paper is to study and make real-time vehicular traffic predictions while incorporating the effect of weather conditions. To fill the previously mentioned gaps, our prediction model uses a real-time driving distance between sensors to build a distance matrix or spatial adjacency matrix and capture spatial correlation. In addition, our prediction model considers the effect of six types of weather conditions and has an attention mechanism in both spatial and temporal data aggregation. Our prediction model efficiently captures the spatial and temporal correlation between traffic events, and it relies on the graph attention network (GAT) and Bidirectional bidirectional long short-term memory (Bi-LSTM) plus attention layers and is called GAT-BILSTMA.Keywords: deep learning, real time prediction, GAT, Bi-LSTM, attention
Procedia PDF Downloads 721490 A Systematic Review on Lifelong Learning Programs for Community-Dwelling Older Adults
Authors: Xi Vivien Wu, Emily Neo Kim Ang, Yi Jung Tung, Wenru Wang
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Background and Objective: The increase in life expectancy and emphasis on self-reliance for the older adults are global phenomena. As such, lifelong learning in the community is considered a viable means of promoting successful and active aging. This systematic review aims to examine various lifelong learning programs for community-dwelling older adults and to synthesize the contents and outcomes of these lifelong learning programs. Methods: A systematic search was conducted in July to December 2016. Two reviewers were engaged in the process to ensure creditability of the selection process. Narrative description and analysis were applied with the support of a tabulation of key data including study design, interventions, and outcomes. Results: Eleven articles, which consisted of five randomized controlled trials and six quasi-experimental studies, were included in this review. Interventions included e-health literacy programs with the aid of computers and the Internet (n=4), computer and Internet training (n=3), physical fitness programs (n=2), music program (n=1), and intergenerational program (n=1). All studies used objective measurement tools to evaluate the outcomes of the study. Conclusion: The systematic review indicated lifelong learning programs resulted in positive outcomes in terms of physical health, mental health, social behavior, social support, self-efficacy and confidence in computer usage, and increased e-health literacy efficacy. However, the lifelong learning programs face challenges such as funding shortages, program cuts, and increasing costs. A comprehensive lifelong learning program could be developed to enhance the well-being of the older adults at a more holistic level. Empirical research can be done to explore the effectiveness of this comprehensive lifelong learning program.Keywords: community-dwelling older adults, e-health literacy program, lifelong learning program, the wellbeing of the older adults
Procedia PDF Downloads 1641489 Mode II Fracture Toughness of Hybrid Fiber Reinforced Concrete
Authors: H. S. S Abou El-Mal, A. S. Sherbini, H. E. M. Sallam
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Mode II fracture toughness (KIIc) of fiber reinforced concrete has been widely investigated under various patterns of testing geometries. The effect of fiber type, concrete matrix properties, and testing mechanisms were extensively studied. The area of hybrid fiber addition shows a lake of reported research data. In this paper an experimental investigation of hybrid fiber embedded in high strength concrete matrix is reported. Three different types of fibers; namely steel (S), glass (G), and polypropylene (PP) fibers were mixed together in four hybridization patterns, (S/G), (S/PP), (G/PP), (S/G/PP) with constant cumulative volume fraction (Vf) of 1.5%. The concrete matrix properties were kept the same for all hybrid fiber reinforced concrete patterns. In an attempt to estimate a fairly accepted value of fracture toughness KIIc, four testing geometries and loading types are employed in this investigation. Four point shear, Brazilian notched disc, double notched cube, and double edge notched specimens are investigated in a trial to avoid the limitations and sensitivity of each test regarding geometry, size effect, constraint condition, and the crack length to specimen width ratio a/w. The addition of all hybridization patterns of fiber reduced the compressive strength and increased mode II fracture toughness in pure mode II tests. Mode II fracture toughness of concrete KIIc decreased with the increment of a/w ratio for all concretes and test geometries. Mode II fracture toughness KIIc is found to be sensitive to the hybridization patterns of fiber. The (S/PP) hybridization pattern showed higher values than all other patterns, while the (S/G/PP) showed insignificant enhancement on mode II fracture toughness (KIIc). Four point shear (4PS) test set up reflects the most reliable values of mode II fracture toughness KIIc of concrete. Mode II fracture toughness KIIc of concrete couldn’t be assumed as a real material property.Keywords: fiber reinforced concrete, Hybrid fiber, Mode II fracture toughness, testing geometry
Procedia PDF Downloads 3271488 Fused Deposition Modeling Printing of Bioinspired Triply Periodic Minimal Surfaces Based Polyvinylidene Fluoride Materials for Scaffold Development in Biomedical Application
Authors: Farusil Najeeb Mullaveettil, Rolanas Dauksevicius
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Cellular structures produced by additive manufacturing have earned wide research attention due to their unique specific strength and energy absorption potentiality. The literature review concludes that pattern type and density are vital parameters that affect the mechanical properties of parts formed by additive manufacturing techniques and have an influence on printing time and material consumption. Fused deposition modeling technique (FDM) is used here to produce Polyvinylidene fluoride (PVDF) parts. In this work, patterns are based on triply periodic minimal surfaces (TPMS) produced by PVDF-based filaments using the FDM technique. PVDF homopolymer filament Fluorinar-H™ and PVDF copolymer filament Fluorinar-C™ are printed with three types of TPMS patterns. The patterns printed are Gyroid, Schwartz diamond, and Schwartz primitive. Tensile, flexural, and compression tests under quasi-static loading conditions are performed in compliance with ISO standards. The investigation elucidates the deformation mechanisms and a study that establishes a relationship between the printed and nominal specimens' dimensional accuracy. In comparison to the examined TPMS pattern, Schwartz diamond showed a higher relative elastic modulus and strength than the other patterns in tensile loading, and the Gyroid pattern showed the highest mechanical characteristics in flexural loading. The concluded results could be utilized to produce informed cellular designs for biomedical and mechanical applications.Keywords: additive manufacturing, FDM, PVDF, gyroid, schwartz primitive, schwartz diamond, TPMS, tensile, flexural
Procedia PDF Downloads 1421487 Optimization of Acid Treatments by Assessing Diversion Strategies in Carbonate and Sandstone Formations
Authors: Ragi Poyyara, Vijaya Patnana, Mohammed Alam
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When acid is pumped into damaged reservoirs for damage removal/stimulation, distorted inflow of acid into the formation occurs caused by acid preferentially traveling into highly permeable regions over low permeable regions, or (in general) into the path of least resistance. This can lead to poor zonal coverage and hence warrants diversion to carry out an effective placement of acid. Diversion is desirably a reversible technique of temporarily reducing the permeability of high perm zones, thereby forcing the acid into lower perm zones. The uniqueness of each reservoir can pose several challenges to engineers attempting to devise optimum and effective diversion strategies. Diversion techniques include mechanical placement and/or chemical diversion of treatment fluids, further sub-classified into ball sealers, bridge plugs, packers, particulate diverters, viscous gels, crosslinked gels, relative permeability modifiers (RPMs), foams, and/or the use of placement techniques, such as coiled tubing (CT) and the maximum pressure difference and injection rate (MAPDIR) methodology. It is not always realized that the effectiveness of diverters greatly depends on reservoir properties, such as formation type, temperature, reservoir permeability, heterogeneity, and physical well characteristics (e.g., completion type, well deviation, length of treatment interval, multiple intervals, etc.). This paper reviews the mechanisms by which each variety of diverter functions and discusses the effect of various reservoir properties on the efficiency of diversion techniques. Guidelines are recommended to help enhance productivity from zones of interest by choosing the best methods of diversion while pumping an optimized amount of treatment fluid. The success of an overall acid treatment often depends on the effectiveness of the diverting agents.Keywords: diversion, reservoir, zonal coverage, carbonate, sandstone
Procedia PDF Downloads 4321486 Physicochemical Characterization of Asphalt Ridge Froth Bitumen
Authors: Nader Nciri, Suil Song, Namho Kim, Namjun Cho
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Properties and compositions of bitumen and bitumen-derived liquids have significant influences on the selection of recovery, upgrading and refining processes. Optimal process conditions can often be directly related to these properties. The end uses of bitumen and bitumen products are thus related to their compositions. Because it is not possible to conduct a complete analysis of the molecular structure of bitumen, characterization must be made in other terms. The present paper focuses on physico-chemical analysis of two different types of bitumens. These bitumen samples were chosen based on: the original crude oil (sand oil and crude petroleum), and mode of process. The aim of this study is to determine both the manufacturing effect on chemical species and the chemical organization as a function of the type of bitumen sample. In order to obtain information on bitumen chemistry, elemental analysis (C, H, N, S, and O), heavy metal (Ni, V) concentrations, IATROSCAN chromatography (thin layer chromatography-flame ionization detection), FTIR spectroscopy, and 1H NMR spectroscopy have all been used. The characterization includes information about the major compound types (saturates, aromatics, resins and asphaltenes) which can be compared with similar data for other bitumens, more importantly, can be correlated with data from petroleum samples for which refining characteristics are known. Examination of Asphalt Ridge froth bitumen showed that it differed significantly from representative petroleum pitches, principally in their nonhydrocarbon content, heavy metal content and aromatic compounds. When possible, properties and composition were related to recovery and refining processes. This information is important because of the effects that composition has on recovery and processing reactions.Keywords: froth bitumen, oil sand, asphalt ridge, petroleum pitch, thin layer chromatography-flame ionization detection, infrared spectroscopy, 1H nuclear magnetic resonance spectroscopy
Procedia PDF Downloads 4271485 Simulating Studies on Phosphate Removal from Laundry Wastewater Using Biochar: Dudinin Approach
Authors: Eric York, James Tadio, Silas Owusu Antwi
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Laundry wastewater contains a diverse range of chemical pollutants that can have detrimental effects on human health and the environment. In this study, simulation studies by Spyder Python software v 3.2 to assess the efficacy of biochar in removing PO₄³⁻ from wastewater were conducted. Through modeling and simulation, the mechanisms involved in the adsorption process of phosphate by biochar were studied by altering variables which is specific to the phosphate from common laundry phosphate detergents, such as the aqueous solubility, initial concentration, and temperature using the Dudinin Approach (DA). Results showed that the concentration equilibrate at near the highest concentrations for Sugar beet-120 mgL⁻¹, Tailing-85 mgL⁻¹, CaO- rich-50 mgL⁻¹, Eggshell and rice straw-48 mgL⁻¹, Undaria Pinnatifida Roots-190 mgL⁻¹, Ca-Alginate Granular Beads -240 mgL⁻¹, Laminaria Japonica Powder -900 mgL⁻¹, Pinesaw dust-57 mgL⁻¹, Ricehull-190 mgL⁻¹, sesame straw- 470 mgL⁻¹, Sugar Bagasse-380 mgL⁻¹, Miscanthus Giganteus-240 mgL⁻¹, Wood Bc-130 mgL⁻¹, Pine-25 mgL⁻¹, Sawdust-6.8 mgL⁻¹, Sewage Sludge-, Rice husk-12 mgL⁻¹, Corncob-117 mgL⁻¹, Maize straw- 1800 mgL⁻¹ while Peanut -Eucalyptus polybractea-, Crawfish equilibrated at near concentration. CO₂ activated Thalia, sewage sludge biochar, Broussonetia Papyrifera Leaves equilibrated just at the lower concentration. Only Soyer bean Stover exhibited a sharp rise and fall peak in mid-concentration at 2 mgL⁻¹ volume. The modelling results were consistent with experimental findings from the literature, ensuring the accuracy, repeatability, and reliability of the simulation study. The simulation study provided insights into adsorption for PO₄³⁻ from wastewater by biochar using concentration per volume that can be adsorbed ideally under the given conditions. Studies showed that applying the principle experimentally in real wastewater with all its complexity is warranted and not far-fetched.Keywords: simulation studies, phosphate removal, biochar, adsorption, wastewater treatment
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