Search results for: Green steel
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 3800

Search results for: Green steel

680 Sulfonic Acid Functionalized Ionic Liquid in Combinatorial Approach: A Recyclable and Water Tolerant-Acidic Catalyst for Friedlander Quinoline Synthesis

Authors: Jafar Akbari

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Quinolines are very important compounds partially because of their pharmacological properties which include wide applications in medicinal chemistry. notable among them are antimalarial drugs, anti-inflammatory agents, antiasthamatic, antibacterial, antihypertensive, and tyrosine kinase inhibiting agents. Despite quinoline usage in pharmaceutical and other industries, comparatively few methods for their preparation have been reported.The Friedlander annulation is one of the simplest and most straightforward methods for the synthesis of poly substituted quinolines. Although, modified methods employing lewis or br¢nsted acids have been reported for the synthesis of quinolines, the development of water stable acidic catalyst for quinoline synthesis is quite desirable. One of the most remarkable features of ionic liquids is that the yields can be optimized by changing the anions or the cations. Recently, sulfonic acid functionalized ionic liquids were used as solvent-catalyst for several organic reactions. We herein report the one pot domino approach for the synthesis of quinoline derivatives in Friedlander manner using TSIL as a catalyst. These ILs are miscible in water, and their homogeneous system is readily separated from the reaction product, combining advantages of both homogeneous and heterogeneous catalysis. In this reaction, the catalyst plays a dual role; it ensures an effective condensation and cyclization of 2-aminoaryl ketone with second carbonyl group and it also promotes the aromatization to the final product. Various types of quinolines from 2-aminoaryl ketones and β-ketoesters/ketones were prepared in 85-98% yields using the catalytic system of SO3-H functionalized ionic liquid/H2O. More importantly, the catalyst could be easily recycled for five times without loss of much activity.

Keywords: antimalarial drugs, green chemistry, ionic liquid, quinolines

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679 Sustainable Design Features Implementing Public Rental Housing for Remodeling

Authors: So-Young Lee, Myoung-Won Oh, Soon-Cheol Eom, Yeon-Won Suh

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Buildings produce more than one thirds of the total energy consumption and CO₂ emissions. Korean government agency pronounced and initiated Zero Energy Buildings policy for construction as of 2025. The net zero energy design features include passive (daylight, layout, materials, insulation, finishes, etc.) and active (renewable energy sources) elements. The Zero Energy House recently built in Nowon-gu, Korea is provided for 121 households as a public rental housing complex. However most of public rental housing did not include sustainable features which can reduce housing maintaining cost significantly including energy cost. It is necessary to implement net zero design features to the obsolete public rental housing during the remodeling procedure since it can reduce housing cost in long term. The purpose of this study is to investigate sustainable design elements implemented in Net Zero Energy House in Korea and passive and active housing design features in order to apply the sustainable features to the case public rental apartment for remodeling. Housing complex cases in this study are Nowan zero Energy house, Gangnam Bogemjari House, and public rental housings built in more than 20 years in Seoul areas. As results, energy consumption in public rental housing built in 5-years can be improved by exterior surfaces. Energy optimizing in case housing built in more than 20 years can be enhanced by renovated materials, insulation, replacement of windows, exterior finishes, lightings, gardening, water, renewable energy installation, Green IT except for sunlight and layout of buildings. Further life costing analysis is needed for energy optimizing for case housing alternatives.

Keywords: affordable housing, remodeling, sustainable design, zero-energy house

Procedia PDF Downloads 189
678 Sensor and Actuator Fault Detection in Connected Vehicles under a Packet Dropping Network

Authors: Z. Abdollahi Biron, P. Pisu

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Connected vehicles are one of the promising technologies for future Intelligent Transportation Systems (ITS). A connected vehicle system is essentially a set of vehicles communicating through a network to exchange their information with each other and the infrastructure. Although this interconnection of the vehicles can be potentially beneficial in creating an efficient, sustainable, and green transportation system, a set of safety and reliability challenges come out with this technology. The first challenge arises from the information loss due to unreliable communication network which affects the control/management system of the individual vehicles and the overall system. Such scenario may lead to degraded or even unsafe operation which could be potentially catastrophic. Secondly, faulty sensors and actuators can affect the individual vehicle’s safe operation and in turn will create a potentially unsafe node in the vehicular network. Further, sending that faulty sensor information to other vehicles and failure in actuators may significantly affect the safe operation of the overall vehicular network. Therefore, it is of utmost importance to take these issues into consideration while designing the control/management algorithms of the individual vehicles as a part of connected vehicle system. In this paper, we consider a connected vehicle system under Co-operative Adaptive Cruise Control (CACC) and propose a fault diagnosis scheme that deals with these aforementioned challenges. Specifically, the conventional CACC algorithm is modified by adding a Kalman filter-based estimation algorithm to suppress the effect of lost information under unreliable network. Further, a sliding mode observer-based algorithm is used to improve the sensor reliability under faults. The effectiveness of the overall diagnostic scheme is verified via simulation studies.

Keywords: fault diagnostics, communication network, connected vehicles, packet drop out, platoon

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677 Conceptualizing a Strategic Facilities Management Decision Framework for Heritage Building Maintenance Management

Authors: Adegoriola Mayowa I., Lai Joseph H. K., Yung Esther H. K., Chan Edwin H. K.

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Heritage buildings (HBs) as structures with historical and architectural relevance that form an integral part of contemporary society. These buildings deserve to be protected for as long as possible to retain their significance. Therefore, the need to prioritize HB maintenance management is pertinent. However, the decision-making process of HBMM can be relatively daunting. The decision-making challenge may be attributed to the multiple 'stakeholders' expectation and requirement which needs to be met. To this end, professionals in the built environment have identified the need to apply the strategic concept of facilities management (FM) in decision making. Furthermore, the different maintenance dimensions have been applied to maintenance management of residential, commercial, and health facilities. Unfortunately, these different maintenance approaches, such as FM, sustainable FM, urban FM, green FM, and strategic FM, are yet to be fully explored in the decision-making process of HBMM. To bridge this gap, this study focuses on developing a framework for strategic decision-making HBMM, which helps achieve HBMM sustainability. At the study's inception, relevant works of literature in the domains of HBMM and FM were conducted. This review helped in the identification of contemporary maintenance practices and their applicability to HBMM. Afterward, a conceptual framework to aid decision-making in HBMM was developed. This framework integrated the concept of FM scope (people, place, process, and technology) while ensuring that decisions plans were made at strategic, tactical, and operational levels. Also, the different characteristics of HBs and stakeholders' requirements were considered in the framework. The conceptual framework presents a holistic guide for professionals in HBMM to ensure that decision processes and outcomes are practical and efficient. It also contributes to the existing body of knowledge on the integration of FM in HBMM. Furthermore, it will serve as a basis for future studies by applying the conceptualized framework in actual cases.

Keywords: decision-making, facility management, strategy, sustainability, heritage building, maintenance

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676 Governance Factors of Sustainable Stormwater Management: A Comparative Study of Case Cities in China and Sweden

Authors: Xiujuan Qiao

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Cities worldwide are increasingly adopting sustainable stormwater solutions such as using green infrastructure to mitigate challenges related to stormwater, e.g., pluvial flooding, and stormwater pollution. Barriers caused by governance factors have been identified as the main reason for the slow pace of sustainable stormwater management implementation. In this study, we examined governance factors influencing local implementation in four case cities: Lund and Malmö, Sweden, and Xi’xian New Area and Zhenjiang, China. Based on systems thinking of interrelations between previously identified influencing governance factors in sustainable stormwater management (SSM), we developed a causal loop diagram (SSM-CLD) and used it to analyze 23 semi-structured interviews with local government officers in the four case cities. Based on the results, we created one SSM-CLD for each country and analyzed the main differences between these four SSM-CLDs. The results revealed that differences in governance structures can lead to differences in the influencing governance factors. In top-down political systems, e.g., China, the role of national policy in setting local leaders’ priorities is significant for SSM implementation. In political systems with more power devolved to local governments, e.g., Sweden, public awareness and local government politicians’ priorities are important for SSM implementation. Acquiring funding for long-term maintenance was identified as a challenge in all four cities studied. These results are relevant for policymakers, local government departments, consultancy companies, and researchers seeking a better understanding of how governance factors influence sustainable stormwater management.

Keywords: sustainable stormwater management, causal loop diagram, governance structures, local government priorities, public awareness, maintenance

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675 Investigating Sustainable Construction and Demolition Waste Management Practices in South Africa

Authors: Ademilade J. Aboginije, Clinton O. Aigbavboa

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South Africa is among the emerging economy, which has a policy and suitable environment that dynamically stimulates waste management practices of diverting waste away from landfill through prevention, reuse, recycling, and recovery known as the 4R-approaches. The focus of this paper is to investigate the existing structures and processes that are environmentally responsible, then determine the resource-efficiency of the waste management practices in the South Africa construction industry. This paper indicates the results of an investigation carried out by using a systematic review of several related literatures to assess the sustainability of waste management scenarios with secondary material recovery to pinpoint all influential criteria and consequently, highlights a step by step approach to adequately analyze the process by using the indicators that can clearly and fully value the waste management practices in South Africa. Furthermore, a life cycle Analytical tool is used to support the development of a framework which can be applied in measuring the sustainability of existing waste management practices in South Africa. Finding shows that sustainable C&D waste management practices stance a great prospect far more noticeable in terms of job creation and opportunities, saving cost and conserving natural resources when incorporated, especially in the process of recycling and reusing of C&D waste materials in several construction projects in South Africa. However, there are problems such as; inadequacy of waste to energy plants, low compliances to policies and sustainable principles, lack of enough technical capacities confronting the effectiveness of the current waste management practices. Thus, with the increase in the pursuit of sustainable development in most developing countries, this paper determines how sustainability can be measured and used in top-level decision-making policy within construction and demolition waste management for a sustainable built environment.

Keywords: construction industry, green-star rating, life-cycle analysis, sustainability, zero-waste hierarchy

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674 Impact of Tillage and Crop Establishment on Fertility and Sustainability of the Rice-Wheat Cropping System in Inceptisols of Varanasi, Up, India

Authors: Pramod Kumar Sharma, Pratibha Kumari, Udai Pratap Singh, Sustainability

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In the Indo-Gangetic Plains of South-East Asia, the rice-wheat cropping system (RWCS) is dominant with conventional tillage (CT) without residue management, which shows depletion of soil fertility and non-sustainable crop productivity. Hence, this investigation was planned to identify suitable natural resource management practices involving different tillage and crop establishment (TCE) methods along with crop residue and their effects, on the sustainability of dominant cropping systems through enhancing soil fertility and productivity. This study was conducted for two consecutive years 2018-19 and 2019-20 on a long-term field experiment that was started in the year 2015-16 taking six different combinations of TCE methods viz. CT, partial conservation agriculture (PCA) i.e. anchored residue of rice and full conservation agriculture (FCA)] i.e. anchored residue of rice and wheat under RWCS in terms of crop productivity, sustainability of soil health, and crop nutrition by the crops. Results showed that zero tillage direct-seeded rice (ZTDSR) - zero tillage wheat (ZTW) [FCA + green gram residue retention (RR)] recorded the highest yield attributes and yield during both the crops. Compared to conventional tillage rice (CTR)-conventional tillage wheat (CTW) [residue removal (R 0 )], the soil quality parameters were improved significantly with ZTDSR-ZTW (FCA+RR). Overall, ZTDSR-ZTW (FCA+RR) had higher nutrient uptake by the crops than CT-based treatment CTR-CTW (R 0 ) and CTR-CTW (RI).These results showed that there is significant profitability of yield and resource utilization by the adoption of FCA it may be a better alternative to the dominant tillage system i.e. CT in RWSC.

Keywords: tillage and crop establishment, soil fertility, rice-wheat cropping system, sustainability

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673 Derivation of a Risk-Based Level of Service Index for Surface Street Network Using Reliability Analysis

Authors: Chang-Jen Lan

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Current Level of Service (LOS) index adopted in Highway Capacity Manual (HCM) for signalized intersections on surface streets is based on the intersection average delay. The delay thresholds for defining LOS grades are subjective and is unrelated to critical traffic condition. For example, an intersection delay of 80 sec per vehicle for failing LOS grade F does not necessarily correspond to the intersection capacity. Also, a specific measure of average delay may result from delay minimization, delay equality, or other meaningful optimization criteria. To that end, a reliability version of the intersection critical degree of saturation (v/c) as the LOS index is introduced. Traditionally, the level of saturation at a signalized intersection is defined as the ratio of critical volume sum (per lane) to the average saturation flow (per lane) during all available effective green time within a cycle. The critical sum is the sum of the maximal conflicting movement-pair volumes in northbound-southbound and eastbound/westbound right of ways. In this study, both movement volume and saturation flow are assumed log-normal distributions. Because, when the conditions of central limit theorem obtain, multiplication of the independent, positive random variables tends to result in a log-normal distributed outcome in the limit, the critical degree of saturation is expected to be a log-normal distribution as well. Derivation of the risk index predictive limits is complex due to the maximum and absolute value operators, as well as the ratio of random variables. A fairly accurate functional form for the predictive limit at a user-specified significant level is yielded. The predictive limit is then compared with the designated LOS thresholds for the intersection critical degree of saturation (denoted as X

Keywords: reliability analysis, level of service, intersection critical degree of saturation, risk based index

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672 The Impact of Animal-Assisted Learning on Emotional Wellbeing and Engagement with Reading

Authors: Jill Steel

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Introduction: Animal-assisted learning (AAL) interventions are increasing exponentially, yet a paucity of quality research in the field exists. The aim of this study was to evaluate how the promotion of emotional wellbeing, through AAL, in this case, a dog, may support children’s engagement with reading in a Primary 1 classroom. Research indicates that dogs can provide emotional support to children; by forming a trusting attachment with a non-critical ‘friend’ who confers unconditional positive regard on the child, confidence may be boosted and anxiety reduced. By promoting emotional wellbeing through interactions with the dog, it is hoped that children begin to associate reading with feelings of wellbeing, which then results in increased engagement with reading. Methodology: A review of the literature was conducted. The relationship between emotional wellbeing and learning was explored, followed by an examination of the literature relating to Animal-Assisted Therapy and AAL. Scottish educational policy and legislation were analysed to establish the extent to which AAL might be suitable for the Scottish pedagogical context. An empirical study was conducted in a mainstream Primary 1 classroom over a four-week period. An inclusive approach was adopted whereby all children that wanted to interact with the dog were given the opportunity to do so, and all 25 children subsequently chose to participate. Children were not withdrawn from the classroom. Primary methods included interviews, observations, and questionnaires. Three focus children were selected for closer study. Main Results: Results were remarkably close to previous research and literature. Children’s emotional wellbeing was boosted, and engagement in reading improved. Principal Conclusions and Implications for Field: It was concluded that AAL could support emotional wellbeing and, in turn, promote children’s engagement with reading. The main limitation of the study was its short-term nature, and a longer randomised controlled trial with a larger sample, currently being undertaken by the author, would provide a fuller answer to the research question. Barriers to AAL include health and safety concerns and steps to ensure the welfare of the dog.

Keywords: animal-assisted learning, emotional wellbeing, reading, reading to dogs

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671 Taxonomic Study and Environmental Ecology of Parrot (Rose Ringed) in City Mirpurkhas, Sindh, Pakistan

Authors: Aisha Liaquat Ali, Ghulam Sarwar Gachal, Muhammad Yusuf Sheikh

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The Parrot rose ringed (Psittaculla krameri) commonly known as Tota, belongs to the order ‘Psittaciformes’ and family ‘Psittacidea’. Its sub-species inhabiting Pakistan are Psittaculla borealis. The parrot rose-ringed has been categorized the least concern species, the core aim of the present study is to investigate the ecology and taxonomy of parrot (rose-ringed). Sampling was obtained for the taxonomic identification from various adjoining areas in City Mirpurkhas by non-random method, which was conducted from Feb to June 2017. The different parameters measured with the help of a vernier caliper, foot scale, digital weighing machine. Body parameters were measured via; length of body, length of the wings, length of tail, mass in grams. During present study, a total number of 36 specimens were collected from different localities of City Mirpurkhas (38.2%) were male and (62.7%) were female. Maximum population density of Psittaculla Krameri borealis (52.9%) was collected from Sindh Horticulture Research Station (fruit farm) Mirpurkhas. Minimum no: of Psittaculla krameri borealis (5.5%) collected in urban parks. It was observed that Psittaculla krameri borealis were in dense population during the months of ‘May’ and ‘June’ when the temperature ranged between 20°C and 45°C. A Psittaculla krameri borealis female was found the heaviest in body weight. The species of parrot (rose ringed) captured during study having green plumage, coverts were gray, upper beak, red and lower beak black, shorter tail in female long tail in the male which was similar to the Psittaculla krameri borealis.

Keywords: Mirpurkhas Sindh Pakistan, environmental ecology, parrot, rose-ringed, taxonomy

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670 Energy Intensity: A Case of Indian Manufacturing Industries

Authors: Archana Soni, Arvind Mittal, Manmohan Kapshe

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Energy has been recognized as one of the key inputs for the economic growth and social development of a country. High economic growth naturally means a high level of energy consumption. However, in the present energy scenario where there is a wide gap between the energy generation and energy consumption, it is extremely difficult to match the demand with the supply. India being one of the largest and rapidly growing developing countries, there is an impending energy crisis which requires immediate measures to be adopted. In this situation, the concept of Energy Intensity comes under special focus to ensure energy security in an environmentally sustainable way. Energy Intensity is defined as the energy consumed per unit output in the context of industrial energy practices. It is a key determinant of the projections of future energy demands which assists in policy making. Energy Intensity is inversely related to energy efficiency; lesser the energy required to produce a unit of output or service, the greater is the energy efficiency. Energy Intensity of Indian manufacturing industries is among the highest in the world and stands for enormous energy consumption. Hence, reducing the Energy Intensity of Indian manufacturing industries is one of the best strategies to achieve a low level of energy consumption and conserve energy. This study attempts to analyse the factors which influence the Energy Intensity of Indian manufacturing firms and how they can be used to reduce the Energy Intensity. The paper considers six of the largest energy consuming manufacturing industries in India viz. Aluminium, Cement, Iron & Steel Industries, Textile Industries, Fertilizer and Paper industries and conducts a detailed Energy Intensity analysis using the data from PROWESS database of the Centre for Monitoring Indian Economy (CMIE). A total of twelve independent explanatory variables based on various factors such as raw material, labour, machinery, repair and maintenance, production technology, outsourcing, research and development, number of employees, wages paid, profit margin and capital invested have been taken into consideration for the analysis.

Keywords: energy intensity, explanatory variables, manufacturing industries, PROWESS database

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669 Effect of Fiddler Crab Burrows on Bacterial Communities of Mangrove Sediments

Authors: Mohammad Mokhtari, Gires Usup, Zaidi Che Cob

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Bacteria communities as mediators of the biogeochemical process are the main component of the mangrove ecosystems. Crab burrows by increasing oxic-anoxic interfaces and facilitating the flux rate between sediment and tidal water affect biogeochemical properties of sediments. The effect of fiddler crab burrows on the density and diversity of bacteria were investigated to elucidate the effect of burrow on bacterial distribution. Samples collected from the burrow walls of three species of fiddler crabs including Uca paradussumieri, Uca rosea, and Uca forcipata. Sediment properties including grain size, temperature, Redox potential, pH, chlorophyll, water and organic content were measured from the burrow walls to assess the correlation between environmental variables and bacterial communities. Bacteria were enumerated with epifluorescence microscopy after staining with SYBR green. Bacterial DNA extracted from sediment samples and the community profiles of bacteria were determined with Terminal Restriction Fragment Length Polymorphism (T-RFLP). High endemism was observed among bacterial communities. Among the 152 observed OTU’s, 22 were found only in crab burrows. The highest bacterial density and diversity were recorded in burrow wall. The results of ANOSIM indicated a significant difference between the bacterial communities from the three species of fiddler crab burrows. Only 3% of explained bacteria variability in the constrained ordination model of CCA was contributed to depth, while much of the bacteria’s variability was attributed to coarse sand, pH, and chlorophyll content. Our findings suggest that crab burrows by affecting sediment properties such as redox potential, pH, water, and chlorophyll content induce significant effects on the bacterial communities.

Keywords: bioturbation, canonical corresponding analysis, fiddler crab, microbial ecology

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668 Dietary Risk Assessment of Green Leafy Vegetables (GLV) Due to Heavy Metals from Selected Mining Areas

Authors: Simon Mensah Ofosu

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Illicit surface mining activities pollutes agricultural lands and water bodies and results in accumulation of heavy metals in vegetables cultivated in such areas. Heavy metal (HM) accumulation in vegetables is a serious food safety issues due to the adverse effects of metal toxicities, hence the need to investigate the levels of these metals in cultivated vegetables in the eastern region. Cocoyam leaves, cabbage and cucumber were sampled from selected farms in mining areas (Atiwa District) and non -mining areas (Yilo Krobo and East Akim District) of the region for the study. Levels of Cadmium, Lead, Mercury and Arsenic were investigated in the vegetables with Atomic Absorption Spectrometer, and the results statistically analyzed with Microsoft Office Excel (2013) Spread Sheet and ANOVA. Cadmium (Cd) and arsenic (As) were the highest and least concentrated HM in the vegetables sampled, respectively. The mean concentrations of Cd and Pb in cabbage (0.564 mg/kg, 0.470 mg/kg), cucumber (0.389 mg/kg, 0.190 mg/kg), cocoyam leaves (0.410 mg/kg, 0.256 mg/kg) respectively from the mining areas exceeded the permissible limits set by Joint FAO/WHO. The mean concentrations of the metals in vegetables from the mining and non-mining areas varied significantly (P<0.05). The Target Hazard Quotient (THQ) was used to assess the health risk posed to the human population via vegetable consumption. The THQ values of cadmium, mercury, and lead in adults and children through vegetable consumption in the mining areas were greater than 1 (THQ >1). This indicates the potential health risk that the children and adults may be facing. The THQ values of adults and children in the non-mining areas were less than the safe limit of 1 (THQ<1), hence no significant health risk posed to the population from such areas.

Keywords: food safety, risk assessment, illicit mining, public health, contaminated vegetables

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667 High Fidelity Interactive Video Segmentation Using Tensor Decomposition, Boundary Loss, Convolutional Tessellations, and Context-Aware Skip Connections

Authors: Anthony D. Rhodes, Manan Goel

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We provide a high fidelity deep learning algorithm (HyperSeg) for interactive video segmentation tasks using a dense convolutional network with context-aware skip connections and compressed, 'hypercolumn' image features combined with a convolutional tessellation procedure. In order to maintain high output fidelity, our model crucially processes and renders all image features in high resolution, without utilizing downsampling or pooling procedures. We maintain this consistent, high grade fidelity efficiently in our model chiefly through two means: (1) we use a statistically-principled, tensor decomposition procedure to modulate the number of hypercolumn features and (2) we render these features in their native resolution using a convolutional tessellation technique. For improved pixel-level segmentation results, we introduce a boundary loss function; for improved temporal coherence in video data, we include temporal image information in our model. Through experiments, we demonstrate the improved accuracy of our model against baseline models for interactive segmentation tasks using high resolution video data. We also introduce a benchmark video segmentation dataset, the VFX Segmentation Dataset, which contains over 27,046 high resolution video frames, including green screen and various composited scenes with corresponding, hand-crafted, pixel-level segmentations. Our work presents a improves state of the art segmentation fidelity with high resolution data and can be used across a broad range of application domains, including VFX pipelines and medical imaging disciplines.

Keywords: computer vision, object segmentation, interactive segmentation, model compression

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666 N-Heterocyclic Carbene Based Dearomatized Iridium Complex as an Efficient Catalyst towards Carbon-Carbon Bond Formation via Hydrogen Borrowing Strategy

Authors: Mandeep Kaur, Jitendra K. Bera

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The search for atom-economical and green synthetic methods for the synthesis of functionalized molecules has attracted much attention. Metal ligand cooperation (MLC) plays a pivotal role in organometallic catalysis to activate C−H, H−H, O−H, N−H and B−H bonds through reversible bond breaking and bond making process. Towards this goal, a bifunctional N─heterocyclic carbene (NHC) based pyridyl-functionalized amide ligand precursor, and corresponding dearomatized iridium complex was synthesized. The NMR and UV/Vis acid titration study have been done to prove the proton response nature of the iridium complex. Further, the dearomatized iridium complex explored as a catalyst on the platform of MLC via dearomatzation/aromatization mode of action towards atom economical α and β─alkylation of ketones and secondary alcohols by using primary alcohols through hydrogen borrowing methodology. The key features of the catalysis are high turnover frequency (TOF) values, low catalyst loading, low base loading and no waste product. The greener syntheses of quinoline, lactone derivatives and selective alkylation of drug molecules like pregnenolone and testosterone were also achieved successfully. Another structurally similar iridium complex was also synthesized with modified ligand precursor where a pendant amide unit was absent. The inactivity of this analogue iridium complex towards catalysis authenticated the participation of proton responsive imido sidearm of the ligand to accelerate the catalytic reaction. The mechanistic investigation through control experiments, NMR and deuterated labeling study, authenticate the borrowing hydrogen strategy.

Keywords: C-C bond formation, hydrogen borrowing, metal ligand cooperation (MLC), n-heterocyclic carbene

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665 Controlled Growth of Au Hierarchically Ordered Crystals Architectures for Electrochemical Detection of Traces of Molecules

Authors: P. Bauer, K. Mougin, V. Vignal, A. Buch, P. Ponthiaux, D. Faye

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Nowadays, noble metallic nanostructures with unique morphology are widely used as new sensors due to their fascinating optical, electronic and catalytic properties. Among various shapes, dendritic nanostructures have attracted much attention because of their large surface-to-volume ratio, high sensitivity and special texture with sharp tips and nanoscale junctions. Several methods have been developed to fabricate those specific structures such as electrodeposition, photochemical way, seed-mediated growth or wet chemical method. The present study deals with a novel approach for a controlled growth pattern-directed organisation of Au flower-like crystals (NFs) deposited onto stainless steel plates to achieve large-scale functional surfaces. This technique consists in the deposition of a soft nanoporous template on which Au NFs are grown by electroplating and seed-mediated method. Size, morphology, and interstructure distance have been controlled by a site selective nucleation process. Dendritic Au nanostructures have appeared as excellent Raman-active candidates due to the presence of very sharp tips of multi-branched Au nanoparticles that leads to a large local field enhancement and a good SERS sensitivity. In addition, these structures have also been used as electrochemical sensors to detect traces of molecules present in a solution. A correlation of the number of active sites on the surface and the current charge by both colorimetric method and cyclic voltammetry of gold structures have allowed a calibration of the system. This device represents a first step for the fabrication of MEMs platform that could ultimately be integrated into a lab-on-chip system. It also opens pathways to several technologically large-scale nanomaterials fabrication such as hierarchically ordered crystal architectures for sensor applications.

Keywords: dendritic, electroplating, gold, template

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664 Development of Solar Energy Resources for Land along the Transportation Infrastructure: Taking the Lan-Xin Railway in the Silk Road Economic Belt as an Example

Authors: Dan Han, Yukun Zhang, Jie Zheng, Rui Zhang

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Making full use of space along transportation infrastructure to develop renewable energy sources, especially solar energy resources, has become a research focus in relevant fields. In recent years, relevant international researches can be classified into three stages of theoretical and technical exploration, exploratory practice as well as planning implementation. Compared with traditional solar energy development mode, the development of solar energy resources in places along the transportation infrastructure has special advantages, which can also bring forth new opportunities for the development of green transportation. 'Road Integrated Photovoltaic', a development model of combining transport and new energy, has been actively studied and applied in developed countries, but it was still in its infancy in China. 'New Silk Road Economic Belt' has great advantage to carry out the 'Road Integrated Photovoltaic' because of the rich solar energy resources in its path, the shortages of renewable energy, the constraints of agricultural land and other reasons. Especially the massive amount of construction of transportation infrastructure brought by Silk Road Economic Belt, large area of developable land along the transportation line will be generated. Abundant solar energy recourses along the Silk Road will provide extremely superb practical opportunities to the land development along transportation infrastructure. We take PVsyst, GIS and Google map software for simulation of its potential by taking Lan-Xin Railway as an example, so potential electrical energy generation can be quantified and further analyzed. Research of 'New Silk Road Economic Belt' combined with 'Road Integrated Photovoltaic' is a creative development for the along transport and energy infrastructure. It not only can make full use of solar radiation and land in its path, but also bring more long-term advantages and benefits.

Keywords: land use, silk road economic belt, solar energy, transportation infrastructure

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663 High Phosphate-Containing Foods and Beverages: Perceptions of the Future Healthcare Providers on Their Harmful Effect in Excessive Consumption

Authors: ATM Emdadul Haque

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Phosphorus is an essential nutrient which is regularly consumed with food and exists in the body as phosphate. Phosphate is an important component of cellular structures and needed for bone mineralization. Excessive accumulation of phosphate is an important driving factor of mortality in chronic renal failure patients; of relevance, these patients are usually provided health care by doctors, nurses, and pharmacists. Hence, this study was planned to determine the level of awareness of the future healthcare providers about the phosphate-containing foods and beverages and to access their knowledge on the harmful effects of excess phosphate consumption. A questionnaire was developed and distributed among the year-1 medical, nursing and pharmacy students. 432 medical, nursing and pharmacy students responded with age ranging from 18-24 years. About 70% of the respondents were female with a majority (90.7%) from Malay ethnicity. Among the respondents, 29.9% were medical, 35.4% were the pharmacy and 34.7% were nursing students. 79.2% students knew that phosphate was an important component of the body, but only 61.8% knew that consuming too much phosphate could be harmful to the body. Despite 97% of the students knew that carbonated soda contained high sugar, surprisingly 77% of them did not know the presence of high phosphate in the same soda drinks; in the similar line of observation, 67% did not know the presence of it in the fast food. However, it was encouraging that 94% of the students wanted to know more about the effects of phosphate consumption, 74.3% were willing to give up drinking soda and eating fast food, and 52% considered taking green coconut water instead of soda drinks. It is, therefore, central to take an educational initiative to increase the awareness of the future healthcare providers about phosphate-containing food and its harmful effects in excessive consumptions.

Keywords: high phosphate containing foods and beverages, excessive consumption, future health care providers, phosphorus

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662 Prolonged Synthesis of Chitin Polysaccharide from Chlorovirus System

Authors: Numfon Rakkhumkaew, Takeru Kawasaki, Makoto Fujie, Takashi Yamada

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Chlorella viruses or chloroviruses contain a gene that encodes a function for chitin synthesis, which is expressed early in viral infection to produce chitin polysaccharide, a polymer of β-1, 4-linked GlcNAc, on the outside of Chlorella cell wall. Interestingly, chlorovirus system is an eco-friendly system which converses CO2 and solar energy from the environment into useful materials. However, infected Chlorella cells are lysed at the final stage of viral infection, and this phenomenon is caused the breaking down of polysaccharide. To postpone the lysing period and prolong the synthesis of chitin polysaccharide on cells, the slow growing virus incorporated with aphidicolin treatment, an inhibitor of DNA synthesis, was investigated. In this study, a total of 25 virus isolates from water samples in Japan region were analyzed for CHS (the gene for CH synthase) gene by PCR (polymerase chain reaction). The accumulation and appearance of chitin polysaccharide on infected cells were detected by biotinylated chitin-binding proteins WGA (wheat germ agglutinin)-biotin for chitin in conjunction with avidin-Cy 2 or Cy 3 and investigated by fluorescence microscopy, observed as green or yellow fluorescence over the cell surface. Among all chlorovirus isolates, cells infected with CNF1 revealed the accumulation of chitin over the cell surface within 30 min p.i. and continued to accumulate on cells until 4 h p.i. before cell lyses which was 1.6 times longer accumulation period than cells infected with CVK2 (prototype virus). Furthermore, addition of aphidicolin could extend the chitin accumulation on cells infected with CNF1 until 8 h p.i. before cell lyses. Whereas, CVK2-infected cells treated with aphidicolin could prolong the chitin synthesis only for 6 h p.i. before cell lyses. Therefore, chitin synthesis by Chlorella-virus system could be prolonged by using slow-growing viral isolates and with aphidicolin.

Keywords: chitin, chlorovirus, Chlorella virus, aphidicolin

Procedia PDF Downloads 212
661 Development of Interaction Diagram for Eccentrically Loaded Reinforced Concrete Sandwich Walls with Different Design Parameters

Authors: May Haggag, Ezzat Fahmy, Mohamed Abdel-Mooty, Sherif Safar

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Sandwich sections have a very complex nature due to variability of behavior of different materials within the section. Cracking, crushing and yielding capacity of constituent materials enforces high complexity of the section. Furthermore, slippage between the different layers adds to the section complex behavior. Conventional methods implemented in current industrial guidelines do not account for the above complexities. Thus, a throughout study is needed to understand the true behavior of the sandwich panels thus, increase the ability to use them effectively and efficiently. The purpose of this paper is to conduct numerical investigation using ANSYS software for the structural behavior of sandwich wall section under eccentric loading. Sandwich walls studied herein are composed of two RC faces, a foam core and linking shear connectors. Faces are modeled using solid elements and reinforcement together with connectors are modeled using link elements. The analysis conducted herein is nonlinear static analysis incorporating material nonlinearity, crashing and crushing of concrete and yielding of steel. The model is validated by comparing it to test results in literature. After validation, the model is used to establish extensive parametric analysis to investigate the effect of three key parameters on the axial force bending moment interaction diagram of the walls. These parameters are the concrete compressive strength, face thickness and number of shear connectors. Furthermore, the results of the parametric study are used to predict a coefficient that links the interaction diagram of a solid wall to that of a sandwich wall. The equation is predicted using the parametric study data and regression analysis. The predicted α was used to construct the interaction diagram of the investigated wall and the results were compared with ANSYS results and showed good agreement.

Keywords: sandwich walls, interaction diagrams, numerical modeling, eccentricity, reinforced concrete

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660 Techniques for Seismic Strengthening of Historical Monuments from Diagnosis to Implementation

Authors: Mircan Kaya

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A multi-disciplinary approach is required in any intervention project for historical monuments. Due to the complexity of their geometry, the variable and unpredictable characteristics of original materials used in their creation, heritage structures are peculiar. Their histories are often complex, and they require correct diagnoses to decide on the techniques of intervention. This approach should not only combine technical aspects but also historical research that may help discover phenomena involving structural issues, and acquire a knowledge of the structure on its concept, method of construction, previous interventions, process of damage, and its current state. In addition to the traditional techniques like bed joint reinforcement, the repairing, strengthening and restoration of historical buildings may require several other modern methods which may be described as innovative techniques like pre-stressing and post-tensioning, use of shape memory alloy devices and shock transmission units, shoring, drilling, and the use of stainless steel or titanium. Regardless of the method to be incorporated in the strengthening process, which can be traditional or innovative, it is crucial to recognize that structural strengthening is the process of upgrading the structural system of the existing building with the aim of improving its performance under existing and additional loads like seismic loads. This process is much more complex than dealing with a new construction, owing to the fact that there are several unknown factors associated with the structural system. Material properties, load paths, previous interventions, existing reinforcement are especially important matters to be considered. There are several examples of seismic strengthening with traditional and innovative techniques around the world, which will be discussed in this paper in detail, including their pros and cons. Ultimately, however, the main idea underlying the philosophy of a successful intervention with the most appropriate techniques of strengthening a historic monument should be decided by a proper assessment of the specific needs of the building.

Keywords: bed joint reinforcement, historical monuments, post-tensioning, pre-stressing, seismic strengthening, shape memory alloy devices, shock transmitters, tie rods

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659 The Effect of Withania Somnifera in Alloxan Induced Diabetic Rabbits

Authors: Farah Ali, Tehreem Fayyaz, Musadiq Idris

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The present work was undertaken to investigate effects of various extracts of withania somnifera for anti-diabetic activity in alloxan induced diabetic rabbits. Rabbits were acclimatized for a week to standard laboratory temperature. Animals were fed according to a strict schedule (8 am, 3 pm and 10 pm) with green fodder (Medicago sativa) and tap water ad libitum. Animals were divided into nine groups of six rabbits each in a random manner. Body weights and physical activities of all rabbits were recorded before start of experiments. The animals of group 1 and 2 were given lactose (250 mg/kg, p.o) and Withania somniferaroot powder (100 mg/kg, p.o) respectively daily from day 1-20. Animals of group 3 were given alloxan (100 mg/kg, i.v) as a single dose on day 1. Powdered root of Withania somnifera in the doses of 100, 150, 200 mg/kg and its aqueous and ethanol extracts (equivalent to 200 mg/kg of crude drug) were given to the treated animals (groups 4-8), respectively by oral route for three weeks (day 1-20o.d), along with alloxan (100 mg/kg, i.v) as a single dose on day 1. Group 9 was treated with metformin (200 mg/kg, p.o) daily from day 1-20, along with a single dose of alloxan (100 mg/ kg, i.v) on day 1. Fasting serum glucose concentration in groups 3-9 was increased significantly (p<0.05) on day 3, with a maximum increase (215.3 mg/dl) in animals of toxic control (TC) group (3) on day 21 of the experiment as compared to normal control (NC) group (1). Effects of different doses (100, 150, 200 mg/kg, p.o) of W. somnifera root powder (WS) decreased the fasting serum glucose concentration as compared to toxic control group, with a maximum decrease (88.3 mg/dl) in group 2 (treated control) on day 21 of the experiment. Metformin (200 mg/kg, p.o) (reference control), aqueous extract (AWS) and ethanol extract (EWS) of W. somnifera (equivalent to 100 mg/kg W.somnifera root, p.o) antagonized the effects of alloxan as compared to toxic control group. These results indicate that the W. somnifera possess significant anti–diabetic activity.

Keywords: diabetes, serum, glucose, blood, sugar, rabbits

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658 Environmental Education and Sustainable Development: the Contribution of Eco-Schools Program

Authors: Sara Rute Monteiro Silva Sousa

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Since the second half of the 20th century, environmental problems began to generate deep concern around the world. The harmful effects of human's irresponsible actions are increasingly evident, profoundly affecting biodiversity and even human health. Given the seriousness of this human footprint, governments, organizations, and civil society must all be more proactive and adopt more effective measures to solve environmental problems and promote sustainable development. This can be achieved through different tools, namely through a more efficient education that enables current and future generations to meet their needs in an integrated approach to the economic, social, and environmental dimensions of sustainable development. In this context, schools play a key role, being responsible for educating today's students and tomorrow's leaders, decision makers, intellectuals, managers, politicians, employers, and parents. Aware of this crucial role of education and schools, the Foundation for Environmental Education created the Eco-Schools program in 1992, ensuring that schools develop a whole-school approach to environmental and sus-tainable education. This research aims to increase knowledge and information about the efficiency of the Eco-Schools program as a promoter of more sustainable schools and communities. This research study analyses a specific case of a Portuguese higher education institution in the area of management, accounting, and administration. A description, reflection, and discussion are made on some of the main measures implemented in the last academic year of 2021/22 within the scope of the Eco-Schools program, concluding that, despite some implementation difficulties, the program was successfully developed, involving the participation of students, teachers, staff, and outside school community members, being awarded with the Green Flag as a recognition of its key contribution to a more sustainable society.

Keywords: sustainable development, environmental education, eco-schools program, higher education institutions, portugal

Procedia PDF Downloads 237
657 Enhanced Growth of Microalgae Chlamydomonas reinhardtii Cultivated in Different Organic Waste and Effective Conversion of Algal Oil to Biodiesel

Authors: Ajith J. Kings, L. R. Monisha Miriam, R. Edwin Raj, S. Julyes Jaisingh, S. Gavaskar

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Microalgae are a potential bio-source for rejuvenated solutions in various disciplines of science and technology, especially in medicine and energy. Biodiesel is being replaced for conventional fuels in automobile industries with reduced pollution and equivalent performance. Since it is a carbon neutral fuel by recycling CO2 in photosynthesis, global warming potential can be held in control using this fuel source. One of the ways to meet the rising demand of automotive fuel is to adopt with eco-friendly, green alternative fuels called sustainable microalgal biodiesel. In this work, a microalga Chlamydomonas reinhardtii was cultivated and optimized in different media compositions developed from under-utilized waste materials in lab scale. Using the optimized process conditions, they are then mass propagated in out-door ponds, harvested, dried and oils extracted for optimization in ambient conditions. The microalgal oil was subjected to two step esterification processes using acid catalyst to reduce the acid value (0.52 mg kOH/g) in the initial stage, followed by transesterification to maximize the biodiesel yield. The optimized esterification process parameters are methanol/oil ratio 0.32 (v/v), sulphuric acid 10 vol.%, duration 45 min at 65 ºC. In the transesterification process, commercially available alkali catalyst (KOH) is used and optimized to obtain a maximum biodiesel yield of 95.4%. The optimized parameters are methanol/oil ratio 0.33(v/v), alkali catalyst 0.1 wt.%, duration 90 min at 65 ºC 90 with smooth stirring. Response Surface Methodology (RSM) is employed as a tool for optimizing the process parameters. The biodiesel was then characterized with standard procedures and especially by GC-MS to confirm its compatibility for usage in internal combustion engine.

Keywords: microalgae, organic media, optimization, transesterification, characterization

Procedia PDF Downloads 233
656 Best Combination of Design Parameters for Buildings with Buckling-Restrained Braces

Authors: Ángel de J. López-Pérez, Sonia E. Ruiz, Vanessa A. Segovia

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Buildings vulnerability due to seismic activity has been highly studied since the middle of last century. As a solution to the structural and non-structural damage caused by intense ground motions, several seismic energy dissipating devices, such as buckling-restrained braces (BRB), have been proposed. BRB have shown to be effective in concentrating a large portion of the energy transmitted to the structure by the seismic ground motion. A design approach for buildings with BRB elements, which is based on a seismic Displacement-Based formulation, has recently been proposed by the coauthors in this paper. It is a practical and easy design method which simplifies the work of structural engineers. The method is used here for the design of the structure-BRB damper system. The objective of the present study is to extend and apply a methodology to find the best combination of design parameters on multiple-degree-of-freedom (MDOF) structural frame – BRB systems, taking into account simultaneously: 1) initial costs and 2) an adequate engineering demand parameter. The design parameters considered here are: the stiffness ratio (α = Kframe/Ktotal), and the strength ratio (γ = Vdamper/Vtotal); where K represents structural stiffness and V structural strength; and the subscripts "frame", "damper" and "total" represent: the structure without dampers, the BRB dampers and the total frame-damper system, respectively. The selection of the best combination of design parameters α and γ is based on an initial costs analysis and on the structural dynamic response of the structural frame-damper system. The methodology is applied to a 12-story 5-bay steel building with BRB, which is located on the intermediate soil of Mexico City. It is found the best combination of design parameters α and γ for the building with BRB under study.

Keywords: best combination of design parameters, BRB, buildings with energy dissipating devices, buckling-restrained braces, initial costs

Procedia PDF Downloads 255
655 Storm-water Management for Greenfield Area Using Low Impact Development Concept for Town Planning Scheme Mechanism

Authors: Sahil Patel

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Increasing urbanization leads to a concrete forest. The effects of new development practices occur in the natural hydrologic cycle. Here the concerns have been raised about the groundwater recharge in sufficient quantity. With further development, porous surfaces reduce rapidly. A city like Ahmedabad, with a non-perennial river, is 100% dependent on groundwater. The Ahmedabad city receives its domestic use water from the Narmada river, located about 200 km away. The expenses to bring water is much higher. Ahmedabad city receives annually 800 mm rainfall, and mostly this water increases the local level waterlogging problems; after that, water goes to the Sabarmati river and merges into the sea. The existing developed area of Ahmedabad city is very dense, and does not offer many chances to change the built form and increase porous surfaces to absorb storm-water. Therefore, there is a need to plan upcoming areas with more effective solutions to manage storm-water. This paper is focusing on the management of stormwater for new development by retaining natural hydrology. The Low Impact Development (LID) concept is used to manage storm-water efficiently. Ahmedabad city has a tool called the “Town Planning Scheme,” which helps the local body drive new development by land pooling mechanism. This paper gives a detailed analysis of the selected area (proposed Town Planning Scheme area by the local authority) in Ahmedabad. Here the development control regulations for individual developers and some physical elements for public places are presented to manage storm-water. There is a different solution for the Town Planning scheme than that of the conventional way. A local authority can use it for any area, but it can be site-specific. In the end, there are benefits to locals with some financial analysis and comparisons.

Keywords: water management, green field development, low impact development, town planning scheme

Procedia PDF Downloads 129
654 Non-Invasive Techniques of Analysis of Painting in Forensic Fields

Authors: Radka Sefcu, Vaclava Antuskova, Ivana Turkova

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A growing market with modern artworks of a high price leads to the creation and selling of artwork counterfeits. Material analysis is an important part of the process of assessment of authenticity. Knowledge of materials and techniques used by original authors is also necessary. The contribution presents possibilities of non-invasive methods of structural analysis in research on paintings. It was proved that unambiguous identification of many art materials is feasible without sampling. The combination of Raman spectroscopy with FTIR-external reflection enabled the identification of pigments and binders on selected artworks of prominent Czech painters from the first half of the 20th century – Josef Čapek, Emil Filla, Václav Špála and Jan Zrzavý. Raman spectroscopy confirmed the presence of a wide range of white pigments - lead white, zinc white, titanium white, barium white and also Freeman's white as a special white pigment of painting. Good results were obtained for red, blue and most of the yellow areas. Identification of green pigments was often impossible due to strong fluorescence. Oil was confirmed as a binding medium on most of the analyzed artworks via FTIR - external reflection. Collected data present the valuable background for the determination of art materials characteristic for each painter (his palette) and its development over time. Obtained results will further serve as comparative material for the authentication of artworks. This work has been financially supported by the project of the Ministry of the Interior of the Czech Republic: The Development of a Strategic Cluster for Effective Instrumental Technological Methods of Forensic Authentication of Modern Artworks (VJ01010004).

Keywords: non-invasive analysis, Raman spectroscopy, FTIR-external reflection, forgeries

Procedia PDF Downloads 170
653 Characterization of Novel Bi-Directional Promoter from Begomovirus: A Breakthrough in Plant Genomics

Authors: Zainul A. Khan, Malik Z. Abdin, Jawaid A. Khan

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Begomoviruses belonging to the family Geminiviridae, have single-stranded circular DNA genomes that are monopartite or bipartite. The large intergenic region (LIR) of the monopartite and common region (CR) of bipartite begomoviruses possess promoter activity in their genomes. In this study, we have characterized novel bidirectional promoters from Cotton leaf curl Burewala virus (CLCuBuV) genome using high-throughput software and analyzed with PlantCARE, PLACE, Cister and PlantPAN databases. The promoters (Rep and CP promoters) were assayed both in stable and transient expression systems in tobacco as well as cotton plants. Rep and CP-based promoters from the LIR sequence of CLCuBuV and 35S promoter of Cauliflower mosaic virus (CaMV) were tagged with β-glucuronidase (GUS) and green fluorescent protein (GFP) reporter genes to check the efficacy of the promoters. Histochemical staining of GUS in transformed tobacco (Nicotiana tabacum cv. Xanthi) leaves showed higher GUS expression driven by CLCuBuV Rep (complimentary sense) promoter as compared to conventional CaMV 35S promoter and CLCuBuV CP (virion sense) promoter, respectively. GUS activity in individual plant cells driven by CLCuBuV Rep, CLCuBuV CP, and CaMV 35S promoter were quantified through fluorometric GUS assay and reverse transcription quantitative real-time PCR (RT-qPCR). The expression level of GUS tagged with CLCuBuV Rep promoter in the transformed tobacco plants was obtained 2 to 4 fold higher than CaMV 35S promoter. When CLCuBuV CP promoter was used, lower expression level was monitored than that by CaMV 35S promoter. The expression of GFP-tagged with CLCuBuV promoters was also investigated through agroinfiltration. The CLCuBuV Rep promoters showed stronger consistent transient expression in the leaves of N. benthamiana, N. tabacum and Gossypium hirsutum plants when compared with CaMV 35S and CLCuBuV CP promoter.

Keywords: Begmovirus, bidirectional promoter, CaMV 35S promoter, GFP, GUS, qPCR

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652 Investigating the Effect of Using Amorphous Silica Ash Obtained from Rice Husk as a Partial Replacement of Ordinary Portland Cement on the Mechanical and Microstructure Properties of Cement Paste and Mortar

Authors: Aliyu Usman, Muhaammed Bello Ibrahim, Yusuf D. Amartey, Jibrin M. Kaura

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This research is aimed at investigating the effect of using amorphous silica ash (ASA) obtained from rice husk as a partial replacement of ordinary Portland cement (OPC) on the mechanical and microstructure properties of cement paste and mortar. ASA was used in partial replacement of ordinary Portland cement in the following percentages 3 percent, 5 percent, 8 percent and 10 percent. These partial replacements were used to produce Cement-ASA paste and Cement-ASA mortar. ASA was found to contain all the major chemical compounds found in cement with the exception of alumina, which are SiO2 (91.5%), CaO (2.84%), Fe2O3 (1.96%), and loss on ignition (LOI) was found to be 9.18%. It also contains other minor oxides found in cement. Consistency of Cement-ASA paste was found to increase with increase in ASA replacement. Likewise, the setting time and soundness of the Cement-ASA paste also increases with increase in ASA replacements. The test on hardened mortar were destructive in nature which include flexural strength test on prismatic beam (40mm x 40mm x 160mm) at 2, 7, 14 and 28 days curing and compressive strength test on the cube size (40mm x 40mm, by using the auxiliary steel platens) at 2,7,14 and 28 days curing. The Cement-ASA mortar flexural and compressive strengths were found to be increasing with curing time and decreases with cement replacement by ASA. It was observed that 5 percent replacement of cement with ASA attained the highest strength for all the curing ages and all the percentage replacements attained the targeted compressive strength of 6N/mm2 for 28 days. There is an increase in the drying shrinkage of Cement-ASA mortar with curing time, it was also observed that the drying shrinkages for all the curing ages were greater than the control specimen all of which were greater than the code recommendation of less than 0.03%. The scanning electron microscope (SEM) was used to study the Cement-ASA mortar microstructure and to also look for hydration product and morphology.

Keywords: amorphous silica ash, cement mortar, cement paste, scanning electron microscope

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651 Designing Urban Spaces Differently: A Case Study of the Hercity Herstreets Public Space Improvement Initiative in Nairobi, Kenya

Authors: Rehema Kabare

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As urban development initiatives continue to emerge and are implemented amid rapid urbanization and climate change effects in the global south, the plight of women is only being noticed. The pandemic exposed the atrocities, violence and unsafety women and girls face daily both in their homes and in public urban spaces. This is a result of poorly implemented and managed urban structures, which women have been left out of during design and implementation for centuries. The UN Habitat’s HerCity toolkit provides a unique opportunity to change course for both governments and civil society actors where women and girls are onboarded onto urban development initiatives, with their designs and ideas being the focal point. This toolkit proves that when women and girls design, they design for everyone. The HerCity HerStreets, Public Space Improvement Initiative, resulted in a design that focused on two aspects: Streets are a shared resource, and Streets are public spaces. These two concepts illustrate that for streets to be experienced effectively as cultural spaces, they need to be user-friendly, safe and inclusive. This report demonstrates how the HerCity HerStreets as a pilot project can be a benchmark for designing urban spaces in African cities. The project focused on five dimensions to improve the air quality of the space, the space allocation to street vending and bodaboda (passenger motorcycle) stops parking and the green coverage. The process displays how digital tools such as Minecraft and Kobo Toolbox can be utilized to improve citizens’ participation in the development of public spaces, with a special focus on including vulnerable groups such as women, girls and youth.

Keywords: urban space, sustainable development, gender and the city, digital tools and urban development

Procedia PDF Downloads 79