Search results for: cultural-historical activity theory
Commenced in January 2007
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Edition: International
Paper Count: 10416

Search results for: cultural-historical activity theory

156 Mixed Mode Fracture Analyses Using Finite Element Method of Edge Cracked Heavy Annulus Pulley

Authors: Bijit Kalita, K. V. N. Surendra

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The pulley works under both compressive loading due to contacting belt in tension and central torque due to cause rotation. In a power transmission system, the belt pulley assemblies offer a contact problem in the form of two mating cylindrical parts. In this work, we modeled a pulley as a heavy two-dimensional circular disk. Stress analysis due to contact loading in the pulley mechanism is performed. Finite element analysis (FEA) is conducted for a pulley to investigate the stresses experienced on its inner and outer periphery. In most of the heavy-duty applications, most frequently used mechanisms to transmit power in applications such as automotive engines, industrial machines, etc. is Belt Drive. Usually, very heavy circular disks are used as pulleys. A pulley could be entitled as a drum and may have a groove between two flanges around the circumference. A rope, belt, cable or chain can be the driving element of a pulley system that runs over the pulley inside the groove. A pulley is experienced by normal and shear tractions on its contact region in the process of motion transmission. The region may be belt-pulley contact surface or pulley-shaft contact surface. In 1895, Hertz solved the elastic contact problem for point contact and line contact of an ideal smooth object. Afterward, this hypothesis is generally utilized for computing the actual contact zone. Detailed stress analysis in such contact region of such pulleys is quite necessary to prevent early failure. In this paper, the results of the finite element analyses carried out on the compressed disk of a belt pulley arrangement using fracture mechanics concepts are shown. Based on the literature on contact stress problem induced in the wide field of applications, generated stress distribution on the shaft-pulley and belt-pulley interfaces due to the application of high-tension and torque was evaluated in this study using FEA concepts. Finally, the results obtained from ANSYS (APDL) were compared with the Hertzian contact theory. The study is mainly focused on the fatigue life estimation of a rotating part as a component of an engine assembly using the most famous Paris equation. Digital Image Correlation (DIC) analyses have been performed using the open-source software. From the displacement computed using the images acquired at a minimum and maximum force, displacement field amplitude is computed. From these fields, the crack path is defined and stress intensity factors and crack tip position are extracted. A non-linear least-squares projection is used for the purpose of the estimation of fatigue crack growth. Further study will be extended for the various application of rotating machinery such as rotating flywheel disk, jet engine, compressor disk, roller disk cutter etc., where Stress Intensity Factor (SIF) calculation plays a significant role on the accuracy and reliability of a safe design. Additionally, this study will be progressed to predict crack propagation in the pulley using maximum tangential stress (MTS) criteria for mixed mode fracture.

Keywords: crack-tip deformations, contact stress, stress concentration, stress intensity factor

Procedia PDF Downloads 103
155 From Avatars to Humans: A Hybrid World Theory and Human Computer Interaction Experimentations with Virtual Reality Technologies

Authors: Juan Pablo Bertuzzi, Mauro Chiarella

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Employing a communication studies perspective and a socio-technological approach, this paper introduces a theoretical framework for understanding the concept of hybrid world; the avatarization phenomena; and the communicational archetype of co-hybridization. This analysis intends to make a contribution to future design of virtual reality experimental applications. Ultimately, this paper presents an ongoing research project that proposes the study of human-avatar interactions in digital educational environments, as well as an innovative reflection on inner digital communication. The aforementioned project presents the analysis of human-avatar interactions, through the development of an interactive experience in virtual reality. The goal is to generate an innovative communicational dimension that could reinforce the hypotheses presented throughout this paper. Being thought for its initial application in educational environments, the analysis and results of this research are dependent and have been prepared in regard of a meticulous planning of: the conception of a 3D digital platform; the interactive game objects; the AI or computer avatars; the human representation as hybrid avatars; and lastly, the potential of immersion, ergonomics and control diversity that can provide the virtual reality system and the game engine that were chosen. The project is divided in two main axes: The first part is the structural one, as it is mandatory for the construction of an original prototype. The 3D model is inspired by the physical space that belongs to an academic institution. The incorporation of smart objects, avatars, game mechanics, game objects, and a dialogue system will be part of the prototype. These elements have all the objective of gamifying the educational environment. To generate a continuous participation and a large amount of interactions, the digital world will be navigable both, in a conventional device and in a virtual reality system. This decision is made, practically, to facilitate the communication between students and teachers; and strategically, because it will help to a faster population of the digital environment. The second part is concentrated to content production and further data analysis. The challenge is to offer a scenario’s diversity that compels users to interact and to question their digital embodiment. The multipath narrative content that is being applied is focused on the subjects covered in this paper. Furthermore, the experience with virtual reality devices proposes users to experiment in a mixture of a seemingly infinite digital world and a small physical area of movement. This combination will lead the narrative content and it will be crucial in order to restrict user’s interactions. The main point is to stimulate and to grow in the user the need of his hybrid avatar’s help. By building an inner communication between user’s physicality and user’s digital extension, the interactions will serve as a self-guide through the gameworld. This is the first attempt to make explicit the avatarization phenomena and to further analyze the communicational archetype of co-hybridization. The challenge of the upcoming years will be to take advantage from these forms of generalized avatarization, in order to create awareness and establish innovative forms of hybridization.

Keywords: avatar, hybrid worlds, socio-technology, virtual reality

Procedia PDF Downloads 115
154 Autophagy Promotes Vascular Smooth Muscle Cell Migration in vitro and in vivo

Authors: Changhan Ouyang, Zhonglin Xie

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In response to proatherosclerotic factors such as oxidized lipids, or to therapeutic interventions such as angioplasty, stents, or bypass surgery, vascular smooth muscle cells (VSMCs) migrate from the media to the intima, resulting in intimal hyperplasia, restenosis, graft failure, or atherosclerosis. These proatherosclerotic factors also activate autophagy in VSMCs. However, the functional role of autophagy in vascular health and disease remains poorly understood. In the present study, we determined the role of autophagy in the regulation of VSMC migration. Autophagy activity in cultured human aortic smooth muscle cells (HASMCs) and mouse carotid arteries was measured by Western blot analysis of microtubule-associated protein 1 light chain 3 B (LC3B) and P62. The VSMC migration was determined by scratch wound assay and transwell migration assay. Ex vivo smooth muscle cell migration was determined using aortic ring assay. The in vivo SMC migration was examined by staining the carotid artery sections with smooth muscle alpha actin (alpha SMA) after carotid artery ligation. To examine the relationship between autophagy and neointimal hyperplasia, C57BL/6J mice were subjected to carotid artery ligation. Seven days after injury, protein levels of Atg5, Atg7, Beclin1, and LC3B drastically increased and remained higher in the injured arteries three weeks after the injury. In parallel with the activation of autophagy, vascular injury-induced neointimal hyperplasia as estimated by increased intima/media ratio. The en face staining of carotid artery showed that vascular injury enhanced alpha SMA staining in the intimal cells as compared with the sham operation. Treatment of HASMCs with platelet-derived growth factor (PDGF), one of the major factors for vascular remodeling in response to vascular injury, increased Atg7 and LC3 II protein levels and enhanced autophagosome formation. In addition, aortic ring assay demonstrated that PDGF treated aortic rings displayed an increase in neovessel formation compared with control rings. Whole mount staining for CD31 and alpha SMA in PDGF treated neovessels revealed that the neovessel structures were stained by alpha SMA but not CD31. In contrast, pharmacological and genetic suppression of autophagy inhibits VSMC migration. Especially, gene silencing of Atg7 inhibited VSMC migration induced by PDGF. Furthermore, three weeks after ligation, markedly decreased neointimal formation was found in mice treated with chloroquine, an inhibitor of autophagy. Quantitative morphometric analysis of the injured vessels revealed a marked reduction in the intima/media ratio in the mice treated with chloroquine. Conclusion: Autophagy activation increases VSMC migration while autophagy suppression inhibits VSMC migration. These findings suggest that autophagy suppression may be an important therapeutic strategy for atherosclerosis and intimal hyperplasia.

Keywords: autophagy, vascular smooth muscle cell, migration, neointimal formation

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153 A Clustering-Based Approach for Weblog Data Cleaning

Authors: Amine Ganibardi, Cherif Arab Ali

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This paper addresses the data cleaning issue as a part of web usage data preprocessing within the scope of Web Usage Mining. Weblog data recorded by web servers within log files reflect usage activity, i.e., End-users’ clicks and underlying user-agents’ hits. As Web Usage Mining is interested in End-users’ behavior, user-agents’ hits are referred to as noise to be cleaned-off before mining. Filtering hits from clicks is not trivial for two reasons, i.e., a server records requests interlaced in sequential order regardless of their source or type, website resources may be set up as requestable interchangeably by end-users and user-agents. The current methods are content-centric based on filtering heuristics of relevant/irrelevant items in terms of some cleaning attributes, i.e., website’s resources filetype extensions, website’s resources pointed by hyperlinks/URIs, http methods, user-agents, etc. These methods need exhaustive extra-weblog data and prior knowledge on the relevant and/or irrelevant items to be assumed as clicks or hits within the filtering heuristics. Such methods are not appropriate for dynamic/responsive Web for three reasons, i.e., resources may be set up to as clickable by end-users regardless of their type, website’s resources are indexed by frame names without filetype extensions, web contents are generated and cancelled differently from an end-user to another. In order to overcome these constraints, a clustering-based cleaning method centered on the logging structure is proposed. This method focuses on the statistical properties of the logging structure at the requested and referring resources attributes levels. It is insensitive to logging content and does not need extra-weblog data. The used statistical property takes on the structure of the generated logging feature by webpage requests in terms of clicks and hits. Since a webpage consists of its single URI and several components, these feature results in a single click to multiple hits ratio in terms of the requested and referring resources. Thus, the clustering-based method is meant to identify two clusters based on the application of the appropriate distance to the frequency matrix of the requested and referring resources levels. As the ratio clicks to hits is single to multiple, the clicks’ cluster is the smallest one in requests number. Hierarchical Agglomerative Clustering based on a pairwise distance (Gower) and average linkage has been applied to four logfiles of dynamic/responsive websites whose click to hits ratio range from 1/2 to 1/15. The optimal clustering set on the basis of average linkage and maximum inter-cluster inertia results always in two clusters. The evaluation of the smallest cluster referred to as clicks cluster under the terms of confusion matrix indicators results in 97% of true positive rate. The content-centric cleaning methods, i.e., conventional and advanced cleaning, resulted in a lower rate 91%. Thus, the proposed clustering-based cleaning outperforms the content-centric methods within dynamic and responsive web design without the need of any extra-weblog. Such an improvement in cleaning quality is likely to refine dependent analysis.

Keywords: clustering approach, data cleaning, data preprocessing, weblog data, web usage data

Procedia PDF Downloads 155
152 An Evaluation of a Prototype System for Harvesting Energy from Pressurized Pipeline Networks

Authors: Nicholas Aerne, John P. Parmigiani

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There is an increasing desire for renewable and sustainable energy sources to replace fossil fuels. This desire is the result of several factors. First, is the role of fossil fuels in climate change. Scientific data clearly shows that global warming is occurring. It has also been concluded that it is highly likely human activity; specifically, the combustion of fossil fuels, is a major cause of this warming. Second, despite the current surplus of petroleum, fossil fuels are a finite resource and will eventually become scarce and alternatives, such as clean or renewable energy will be needed. Third, operations to obtain fossil fuels such as fracking, off-shore oil drilling, and strip mining are expensive and harmful to the environment. Given these environmental impacts, there is a need to replace fossil fuels with renewable energy sources as a primary energy source. Various sources of renewable energy exist. Many familiar sources obtain renewable energy from the sun and natural environments of the earth. Common examples include solar, hydropower, geothermal heat, ocean waves and tides, and wind energy. Often obtaining significant energy from these sources requires physically-large, sophisticated, and expensive equipment (e.g., wind turbines, dams, solar panels, etc.). Other sources of renewable energy are from the man-made environment. An example is municipal water distribution systems. The movement of water through the pipelines of these systems typically requires the reduction of hydraulic pressure through the use of pressure reducing valves. These valves are needed to reduce upstream supply-line pressures to levels suitable downstream users. The energy associated with this reduction of pressure is significant but is currently not harvested and is simply lost. While the integrity of municipal water supplies is of paramount importance, one can certainly envision means by which this lost energy source could be safely accessed. This paper provides a technical description and analysis of one such means by the technology company InPipe Energy to generate hydroelectricity by harvesting energy from municipal water distribution pressure reducing valve stations. Specifically, InPipe Energy proposes to install hydropower turbines in parallel with existing pressure reducing valves in municipal water distribution systems. InPipe Energy in partnership with Oregon State University has evaluated this approach and built a prototype system at the O. H. Hinsdale Wave Research Lab. The Oregon State University evaluation showed that the prototype system rapidly and safely initiates, maintains, and ceases power production as directed. The outgoing water pressure remained constant at the specified set point throughout all testing. The system replicates the functionality of the pressure reducing valve and ensures accurate control of down-stream pressure. At a typical water-distribution-system pressure drop of 60 psi the prototype, operating at an efficiency 64%, produced approximately 5 kW of electricity. Based on the results of this study, this proposed method appears to offer a viable means of producing significant amounts of clean renewable energy from existing pressure reducing valves.

Keywords: pressure reducing valve, renewable energy, sustainable energy, water supply

Procedia PDF Downloads 179
151 Political Communication in Twitter Interactions between Government, News Media and Citizens in Mexico

Authors: Jorge Cortés, Alejandra Martínez, Carlos Pérez, Anaid Simón

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The presence of government, news media, and general citizenry in social media allows considering interactions between them as a form of political communication (i.e. the public exchange of contradictory discourses about politics). Twitter’s asymmetrical following model (users can follow, mention or reply to other users that do not follow them) could foster alternative democratic practices and have an impact on Mexican political culture, which has been marked by a lack of direct communication channels between these actors. The research aim is to assess Twitter’s role in political communication practices through the analysis of interaction dynamics between government, news media, and citizens by extracting and visualizing data from Twitter’s API to observe general behavior patterns. The hypothesis is that regardless the fact that Twitter’s features enable direct and horizontal interactions between actors, users repeat traditional dynamics of interaction, without taking full advantage of the possibilities of this medium. Through an interdisciplinary team including Communication Strategies, Information Design, and Interaction Systems, the activity on Twitter generated by the controversy over the presence of Uber in Mexico City was analysed; an issue of public interest, involving aspects such as public opinion, economic interests and a legal dimension. This research includes techniques from social network analysis (SNA), a methodological approach focused on the comprehension of the relationships between actors through the visual representation and measurement of network characteristics. The analysis of the Uber event comprised data extraction, data categorization, corpus construction, corpus visualization and analysis. On the recovery stage TAGS, a Google Sheet template, was used to extract tweets that included the hashtags #UberSeQueda and #UberSeVa, posts containing the string Uber and tweets directed to @uber_mx. Using scripts written in Python, the data was filtered, discarding tweets with no interaction (replies, retweets or mentions) and locations outside of México. Considerations regarding bots and the omission of anecdotal posts were also taken into account. The utility of graphs to observe interactions of political communication in general was confirmed by the analysis of visualizations generated with programs such as Gephi and NodeXL. However, some aspects require improvements to obtain more useful visual representations for this type of research. For example, link¬crossings complicates following the direction of an interaction forcing users to manipulate the graph to see it clearly. It was concluded that some practices prevalent in political communication in Mexico are replicated in Twitter. Media actors tend to group together instead of interact with others. The political system tends to tweet as an advertising strategy rather than to generate dialogue. However, some actors were identified as bridges establishing communication between the three spheres, generating a more democratic exercise and taking advantage of Twitter’s possibilities. Although interactions in Twitter could become an alternative to political communication, this potential depends on the intentions of the participants and to what extent they are aiming for collaborative and direct communications. Further research is needed to get a deeper understanding on the political behavior of Twitter users and the possibilities of SNA for its analysis.

Keywords: interaction, political communication, social network analysis, Twitter

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150 Modelling Pest Immigration into Rape Seed Crops under Past and Future Climate Conditions

Authors: M. Eickermann, F. Ronellenfitsch, J. Junk

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Oilseed rape (Brassica napus L.) is one of the most important crops throughout Europe, but pressure due to pest insects and pathogens can reduce yield amount substantially. Therefore, the usage of pesticide applications is outstanding in this crop. In addition, climate change effects can interact with phenology of the host plant and their pests and can apply additional pressure on the yield. Next to the pollen beetle, Meligethes aeneus L., the seed-damaging pest insects, cabbage seed weevil (Ceutorhynchus obstrictus Marsham) and the brassica pod midge (Dasineura brassicae Winn.) are of main economic impact to the yield. While females of C. obstrictus are infesting oilseed rape by depositing single eggs into young pods, the females of D. brassicae are using this local damage in the pod for their own oviposition, while depositing batches of 20-30 eggs. Without a former infestation by the cabbage seed weevil, a significant yield reduction by the brassica pod midge can be denied. Based on long-term, multisided field experiments, a comprehensive data-set on pest migration to crops of B. napus has been built up in the last ten years. Five observational test sides, situated in different climatic regions in Luxembourg were controlled between February until the end of May twice a week. Pest migration was recorded by using yellow water pan-traps. Caught insects were identified in the laboratory according to species specific identification keys. By a combination of pest observations and corresponding meteorological observations, the set-up of models to predict the migration periods of the seed-damaging pests was possible. This approach is the basis for a computer-based decision support tool, to assist the farmer in identifying the appropriate time point of pesticide application. In addition, the derived algorithms of that decision support tool can be combined with climate change projections in order to assess the future potential threat caused by the seed-damaging pest species. Regional climate change effects for Luxembourg have been intensively studied in recent years. Significant changes to wetter winters and drier summers, as well as a prolongation of the vegetation period mainly caused by higher spring temperature, have also been reported. We used the COSMO-CLM model to perform a time slice experiment for Luxembourg with a spatial resolution of 1.3 km. Three ten year time slices were calculated: The reference time span (1991-2000), the near (2041-2050) and the far future (2091-2100). Our results projected a significant shift of pest migration to an earlier onset of the year. In addition, a prolongation of the possible migration period could be observed. Because D. brassiace is depending on the former oviposition activity by C. obstrictus to infest its host plant successfully, the future dependencies of both pest species will be assessed. Based on this approach the future risk potential of both seed-damaging pests is calculated and the status as pest species is characterized.

Keywords: CORDEX projections, decision support tool, Brassica napus, pests

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149 Electrochemical Activity of NiCo-GDC Cermet Anode for Solid Oxide Fuel Cells Operated in Methane

Authors: Kamolvara Sirisuksakulchai, Soamwadee Chaianansutcharit, Kazunori Sato

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Solid Oxide Fuel Cells (SOFCs) have been considered as one of the most efficient large unit power generators for household and industrial applications. The efficiency of an electronic cell depends mainly on the electrochemical reactions in the anode. The development of anode materials has been intensely studied to achieve higher kinetic rates of redox reactions and lower internal resistance. Recent studies have introduced an efficient cermet (ceramic-metallic) material for its ability in fuel oxidation and oxide conduction. This could expand the reactive site, also known as the triple-phase boundary (TPB), thus increasing the overall performance. In this study, a bimetallic catalyst Ni₀.₇₅Co₀.₂₅Oₓ was combined with Gd₀.₁Ce₀.₉O₁.₉₅ (GDC) to be used as a cermet anode (NiCo-GDC) for an anode-supported type SOFC. The synthesis of Ni₀.₇₅Co₀.₂₅Oₓ was carried out by ball milling NiO and Co3O4 powders in ethanol and calcined at 1000 °C. The Gd₀.₁Ce₀.₉O₁.₉₅ was prepared by a urea co-precipitation method. Precursors of Gd(NO₃)₃·6H₂O and Ce(NO₃)₃·6H₂O were dissolved in distilled water with the addition of urea and were heated subsequently. The heated mixture product was filtered and rinsed thoroughly, then dried and calcined at 800 °C and 1500 °C, respectively. The two powders were combined followed by pelletization and sintering at 1100 °C to form an anode support layer. The fabrications of an electrolyte layer and cathode layer were conducted. The electrochemical performance in H₂ was measured from 800 °C to 600 °C while for CH₄ was from 750 °C to 600 °C. The maximum power density at 750 °C in H₂ was 13% higher than in CH₄. The difference in performance was due to higher polarization resistances confirmed by the impedance spectra. According to the standard enthalpy, the dissociation energy of C-H bonds in CH₄ is slightly higher than the H-H bond H₂. The dissociation of CH₄ could be the cause of resistance within the anode material. The results from lower temperatures showed a descending trend of power density in relevance to the increased polarization resistance. This was due to lowering conductivity when the temperature decreases. The long-term stability was measured at 750 °C in CH₄ monitoring at 12-hour intervals. The maximum power density tends to increase gradually with time while the resistances were maintained. This suggests the enhanced stability from charge transfer activities in doped ceria due to the transition of Ce⁴⁺ ↔ Ce³⁺ at low oxygen partial pressure and high-temperature atmosphere. However, the power density started to drop after 60 h, and the cell potential also dropped from 0.3249 V to 0.2850 V. These phenomena was confirmed by a shifted impedance spectra indicating a higher ohmic resistance. The observation by FESEM and EDX-mapping suggests the degradation due to mass transport of ions in the electrolyte while the anode microstructure was still maintained. In summary, the electrochemical test and stability test for 60 h was achieved by NiCo-GDC cermet anode. Coke deposition was not detected after operation in CH₄, hence this confirms the superior properties of the bimetallic cermet anode over typical Ni-GDC.

Keywords: bimetallic catalyst, ceria-based SOFCs, methane oxidation, solid oxide fuel cell

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148 A Digital Environment for Developing Mathematical Abilities in Children with Autism Spectrum Disorder

Authors: M. Isabel Santos, Ana Breda, Ana Margarida Almeida

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Research on academic abilities of individuals with autism spectrum disorder (ASD) underlines the importance of mathematics interventions. Yet the proposal of digital applications for children and youth with ASD continues to attract little attention, namely, regarding the development of mathematical reasoning, being the use of the digital technologies an area of great interest for individuals with this disorder and its use is certainly a facilitative strategy in the development of their mathematical abilities. The use of digital technologies can be an effective way to create innovative learning opportunities to these students and to develop creative, personalized and constructive environments, where they can develop differentiated abilities. The children with ASD often respond well to learning activities involving information presented visually. In this context, we present the digital Learning Environment on Mathematics for Autistic children (LEMA) that was a research project conducive to a PhD in Multimedia in Education and was developed by the Thematic Line Geometrix, located in the Department of Mathematics, in a collaboration effort with DigiMedia Research Center, of the Department of Communication and Art (University of Aveiro, Portugal). LEMA is a digital mathematical learning environment which activities are dynamically adapted to the user’s profile, towards the development of mathematical abilities of children aged 6–12 years diagnosed with ASD. LEMA has already been evaluated with end-users (both students and teacher’s experts) and based on the analysis of the collected data readjustments were made, enabling the continuous improvement of the prototype, namely considering the integration of universal design for learning (UDL) approaches, which are of most importance in ASD, due to its heterogeneity. The learning strategies incorporated in LEMA are: (i) provide options to custom choice of math activities, according to user’s profile; (ii) integrates simple interfaces with few elements, presenting only the features and content needed for the ongoing task; (iii) uses a simple visual and textual language; (iv) uses of different types of feedbacks (auditory, visual, positive/negative reinforcement, hints with helpful instructions including math concept definitions, solved math activities using split and easier tasks and, finally, the use of videos/animations that show a solution to the proposed activity); (v) provides information in multiple representation, such as text, video, audio and image for better content and vocabulary understanding in order to stimulate, motivate and engage users to mathematical learning, also helping users to focus on content; (vi) avoids using elements that distract or interfere with focus and attention; (vii) provides clear instructions and orientation about tasks to ease the user understanding of the content and the content language, in order to stimulate, motivate and engage the user; and (viii) uses buttons, familiarly icons and contrast between font and background. Since these children may experience little sensory tolerance and may have an impaired motor skill, besides the user to have the possibility to interact with LEMA through the mouse (point and click with a single button), the user has the possibility to interact with LEMA through Kinect device (using simple gesture moves).

Keywords: autism spectrum disorder, digital technologies, inclusion, mathematical abilities, mathematical learning activities

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147 Subway Ridership Estimation at a Station-Level: Focus on the Impact of Bus Demand, Commercial Business Characteristics and Network Topology

Authors: Jungyeol Hong, Dongjoo Park

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The primary purpose of this study is to develop a methodological framework to predict daily subway ridership at a station-level and to examine the association between subway ridership and bus demand incorporating commercial business facility in the vicinity of each subway station. The socio-economic characteristics, land-use, and built environment as factors may have an impact on subway ridership. However, it should be considered not only the endogenous relationship between bus and subway demand but also the characteristics of commercial business within a subway station’s sphere of influence, and integrated transit network topology. Regarding a statistical approach to estimate subway ridership at a station level, therefore it should be considered endogeneity and heteroscedastic issues which might have in the subway ridership prediction model. This study focused on both discovering the impacts of bus demand, commercial business characteristics, and network topology on subway ridership and developing more precise subway ridership estimation accounting for its statistical bias. The spatial scope of the study covers entire Seoul city in South Korea and includes 243 stations with the temporal scope set at twenty-four hours with one-hour interval time panels each. The data for subway and bus ridership was collected Seoul Smart Card data from 2015 and 2016. Three-Stage Least Square(3SLS) approach was applied to develop daily subway ridership model as capturing the endogeneity and heteroscedasticity between bus and subway demand. Independent variables incorporating in the modeling process were commercial business characteristics, social-economic characteristics, safety index, transit facility attributes, and dummies for seasons and time zone. As a result, it was found that bus ridership and subway ridership were endogenous each other and they had a significantly positive sign of coefficients which means one transit mode could increase another transportation mode’s ridership. In other words, two transit modes of subway and bus have a mutual relationship instead of the competitive relationship. The commercial business characteristics are the most critical dimension among the independent variables. The variables of commercial business facility rate in the paper containing six types; medical, educational, recreational, financial, food service, and shopping. From the model result, a higher rate in medical, financial buildings, shopping, and food service facility lead to increment of subway ridership at a station, while recreational and educational facility shows lower subway ridership. The complex network theory was applied for estimating integrated network topology measures that cover the entire Seoul transit network system, and a framework for seeking an impact on subway ridership. The centrality measures were found to be significant and showed a positive sign indicating higher centrality led to more subway ridership at a station level. The results of model accuracy tests by out of samples provided that 3SLS model has less mean square error rather than OLS and showed the methodological approach for the 3SLS model was plausible to estimate more accurate subway ridership. Acknowledgement: This research was supported by Basic Science Research Program through the National Research Foundation of Korea(NRF) funded by the Ministry of Science and ICT (2017R1C1B2010175).

Keywords: subway ridership, bus ridership, commercial business characteristic, endogeneity, network topology

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146 Concept Mapping to Reach Consensus on an Antibiotic Smart Use Strategy Model to Promote and Support Appropriate Antibiotic Prescribing in a Hospital, Thailand

Authors: Phenphak Horadee, Rodchares Hanrinth, Saithip Suttiruksa

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Inappropriate use of antibiotics has happened in several hospitals, Thailand. Drug use evaluation (DUE) is one strategy to overcome this difficulty. However, most community hospitals still encounter incomplete evaluation resulting overuse of antibiotics with high cost. Consequently, drug-resistant bacteria have been rising due to inappropriate antibiotic use. The aim of this study was to involve stakeholders in conceptualizing, developing, and prioritizing a feasible intervention strategy to promote and support appropriate antibiotic prescribing in a community hospital, Thailand. Study antibiotics included four antibiotics such as Meropenem, Piperacillin/tazobactam, Amoxicillin/clavulanic acid, and Vancomycin. The study was conducted for the 1-year period between March 1, 2018, and March 31, 2019, in a community hospital in the northeastern part of Thailand. Concept mapping was used in a purposive sample, including doctors (one was an administrator), pharmacists, and nurses who involving drug use evaluation of antibiotics. In-depth interviews for each participant and survey research were conducted to seek the problems for inappropriate use of antibiotics based on drug use evaluation system. Seventy-seven percent of DUE reported appropriate antibiotic prescribing, which still did not reach the goal of 80 percent appropriateness. Meropenem led other antibiotics for inappropriate prescribing. The causes of the unsuccessful DUE program were classified into three themes such as personnel, lack of public relation and communication, and unsupported policy and impractical regulations. During the first meeting, stakeholders (n = 21) expressed the generation of interventions. During the second meeting, participants who were almost the same group of people in the first meeting (n = 21) were requested to independently rate the feasibility and importance of each idea and to categorize them into relevant clusters to facilitate multidimensional scaling and hierarchical cluster analysis. The outputs of analysis included the idealist, cluster list, point map, point rating map, cluster map, and cluster rating map. All of these were distributed to participants (n = 21) during the third meeting to reach consensus on an intervention model. The final proposed intervention strategy included 29 feasible and crucial interventions in seven clusters: development of information technology system, establishing policy and taking it into the action plan, proactive public relations of the policy, action plan and workflow, in cooperation of multidisciplinary teams in drug use evaluation, work review and evaluation with performance reporting, promoting and developing professional and clinical skill for staff with training programs, and developing practical drug use evaluation guideline for antibiotics. These interventions are relevant and fit to several intervention strategies for antibiotic stewardship program in many international organizations such as participation of the multidisciplinary team, developing information technology to support antibiotic smart use, and communication. These interventions were prioritized for implementation over a 1-year period. Once the possibility of each activity or plan is set up, the proposed program could be applied and integrated into hospital policy after evaluating plans. Effectiveness of each intervention could be promoted to other community hospitals to promote and support antibiotic smart use.

Keywords: antibiotic, concept mapping, drug use evaluation, multidisciplinary teams

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145 Overlaps and Intersections: An Alternative Look at Choreography

Authors: Ashlie Latiolais

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Architecture, as a discipline, is on a trajectory of extension beyond the boundaries of buildings and, more increasingly, is coupled with research that connects to alternative and typically disjointed disciplines. A “both/and” approach and (expanded) definition of architecture, as depicted here, expands the margins that contain the profession. Figuratively, architecture is a series of edges, events, and occurrences that establishes a choreography or stage by which humanity exists. The way in which architecture controls and suggests the movement through these spaces, being within a landscape, city, or building, can be viewed as a datum by which the “dance” of everyday life occurs. This submission views the realm of architecture through the lens of movement and dance as a cross-fertilizer of collaboration, tectonic, and spatial geometry investigations. “Designing on digital programs puts architects at a distance from the spaces they imagine. While this has obvious advantages, it also means that they lose the lived, embodied experience of feeling what is needed in space—meaning that some design ideas that work in theory ultimately fail in practice.” By studying the body in motion through real-time performance, a more holistic understanding of architectural space surfaces and new prospects for theoretical teaching pedagogies emerge. The atypical intersection rethinks how architecture is considered, created, and tested, similar to how “dance artists often do this by thinking through the body, opening pathways and possibilities that might not otherwise be accessible” –this is the essence of this poster submission as explained through unFOLDED, a creative performance work. A new languageismaterialized through unFOLDED, a dynamic occupiable installation by which architecture is investigated through dance, movement, and body analysis. The entry unfolds a collaboration of an architect, dance choreographer, musicians, video artist, and lighting designers to re-create one of the first documented avant-garde performing arts collaborations (Matisse, Satie, Massine, Picasso) from the Ballet Russes in 1917, entitled Parade. Architecturally, this interdisciplinary project orients and suggests motion through structure, tectonic, lightness, darkness, and shadow as it questions the navigation of the dark space (stage) surrounding the installation. Artificial light via theatrical lighting and video graphics brought the blank canvas to life – where the sensitive mix of musicality coordinated with the structure’s movement sequencing was certainly a challenge. The upstage light from the video projections created both flickered contextual imagery and shadowed figures. When the dancers were either upstage or downstage of the structure, both silhouetted figures and revealed bodies are experienced as dancer-controlled installation manipulations occurred throughout the performance. The experimental performance, through structure, prompted moving (dancing) bodies in space, where the architecture served as a key component to the choreography itself. The tectonic of the delicate steel structure allowed for the dancers to interact with the installation, which created a variety of spatial conditions – the contained box of three-dimensional space, to a wall, and various abstracted geometries in between. The development of this research unveils the new role of an Architect as a Choreographer of the built environment.

Keywords: dance, architecture, choreography, installation, architect, choreographer, space

Procedia PDF Downloads 68
144 Heritage, Cultural Events and Promises for Better Future: Media Strategies for Attracting Tourism during the Arab Spring Uprisings

Authors: Eli Avraham

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The Arab Spring was widely covered in the global media and the number of Western tourists traveling to the area began to fall. The goal of this study was to analyze which media strategies marketers in Middle Eastern countries chose to employ in their attempts to repair the negative image of the area in the wake of the Arab Spring. Several studies were published concerning image-restoration strategies of destinations during crises around the globe; however, these strategies were not part of an overarching theory, conceptual framework or model from the fields of crisis communication and image repair. The conceptual framework used in the current study was the ‘multi-step model for altering place image’, which offers three types of strategies: source, message and audience. Three research questions were used: 1.What public relations crisis techniques and advertising campaign components were used? 2. What media policies and relationships with the international media were adopted by Arab officials? 3. Which marketing initiatives (such as cultural and sports events) were promoted? This study is based on qualitative content analysis of four types of data: 1) advertising components (slogans, visuals and text); (2) press interviews with Middle Eastern officials and marketers; (3) official media policy adopted by government decision-maker (e.g. boycotting or arresting newspeople); and (4) marketing initiatives (e.g. organizing heritage festivals and cultural events). The data was located in three channels from December 2010, when the events started, to September 31, 2013: (1) Internet and video-sharing websites: YouTube and Middle Eastern countries' national tourism board websites; (2) News reports from two international media outlets, The New York Times and Ha’aretz; these are considered quality newspapers that focus on foreign news and tend to criticize institutions; (3) Global tourism news websites: eTurbo news and ‘Cities and countries branding’. Using the ‘multi-step model for altering place image,’ the analysis reveals that Middle Eastern marketers and officials used three kinds of strategies to repair their countries' negative image: 1. Source (cooperation and media relations; complying, threatening and blocking the media; and finding alternatives to the traditional media) 2. Message (ignoring, limiting, narrowing or reducing the scale of the crisis; acknowledging the negative effect of an event’s coverage and assuring a better future; promotion of multiple facets, exhibitions and softening the ‘hard’ image; hosting spotlight sporting and cultural events; spinning liabilities into assets; geographic dissociation from the Middle East region; ridicule the existing stereotype) and 3. Audience (changing the target audience by addressing others; emphasizing similarities and relevance to specific target audience). It appears that dealing with their image problems will continue to be a challenge for officials and marketers of Middle Eastern countries until the region stabilizes and its regional conflicts are resolved.

Keywords: Arab spring, cultural events, image repair, Middle East, tourism marketing

Procedia PDF Downloads 259
143 Living by the Maramataka: Mahi Maramataka, Indigenous Environmental Knowledge Systems and Wellbeing

Authors: Ayla Hoeta

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The focus of this research is mahi Maramataka, ‘the practices of Maramataka’ as a traditional and evolving knowledge system and its connection to whaanau oranga (wellbeing) and healing. Centering kaupapa Maaori methods and knowledge this research will explore how Maramataka can be used as a tool for oranga and healing for whaanau to engage with different environments aligned with Maramataka flow and optimal time based on the environment. Maramataka is an ancestral lunar environmental knowledge system rooted within korero tuku iho, Maaori creation stories, dating back to the beginning of time. The significance of Maramataka is the ancient environmental knowledge and the connecting energy flow of mauri (life force) between whenua (land), moana (ocean) and rangi (sky). The lunar component of the Maramataka is widely understood and highlights the different phases of the moon. Each moon phase is named with references to puurakau stories and environmental and ecological information. Marama, meaning moon and taka, meaning cycle, is used as a lunar and environmental calendar. There are lunar phases that are optimal for specific activities, such as the Tangaroa phase, a time of abundance and productivity and ocean-based activities like fishing. Other periods in the Maramataka, such as Rakaunui (full moon), connect the highest tides and highest energy of the lunar cycle, ideal for social, physical activity and particularly planting. Other phases like Tamatea are unpredictable whereas Whiro (new moon/s) is reflective, deep and cautious during the darkest nights. Whaanau, particularly in urban settings have become increasingly disconnected from the natural environment, the Maramataka has become a tool that they can connect to which offers an alternative to dominant perspectives of health and is an approach that is uniquely Maaori. In doing so, this research will raise awareness of oranga or lack of oranga, and lived experience of whaanau in Tamaki Makaurau - Aotearoa, on a journey to revival of Maramataka and healing. The research engages Hautu Waka as a methodology using the methods of ancient kaupapa Māori practises based on wayfinding and attunement with the natural environment. Using ancient ways of being, knowing, seeing and doing the Hautu Waka will centre kaupapa Maaori perspectives to process design, reflection and evaluation. The methods of Hautu Waka consists of five interweaving phases, 1) Te Rapunga (the search) in infinite potential, 2) Te Kitenga (the seeing), observations of and attunement to tohu 3) te whainga (the pursuit) and deeply exploring key tohu 4) te whiwhinga (the acquiring), of knowledge and clearer ideas, 5) Te Rawenga (the celebration), reflection and acknowledgement of the journey and achievements. This research is an expansion from my creative practices across whaanau-centred inquiry, to understand the benefits of Maramataka and how it can be embodied and practised in a modern-day context to support oranga and healing. Thus, the goal is to work with kaupapa Maaori methodologies to authenticate as a Maaori practitioner and researcher and allow an authentic indigenous approach to the exploration of Maramataka and through a kaupapa Maaori lens.

Keywords: maramataka (Maaori calendar), tangata (people), taiao (environment), whenua (land), whaanau (family), hautu waka (navigation framework)

Procedia PDF Downloads 44
142 Gas-Phase Noncovalent Functionalization of Pristine Single-Walled Carbon Nanotubes with 3D Metal(II) Phthalocyanines

Authors: Vladimir A. Basiuk, Laura J. Flores-Sanchez, Victor Meza-Laguna, Jose O. Flores-Flores, Lauro Bucio-Galindo, Elena V. Basiuk

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Noncovalent nanohybrid materials combining carbon nanotubes (CNTs) with phthalocyanines (Pcs) is a subject of increasing research effort, with a particular emphasis on the design of new heterogeneous catalysts, efficient organic photovoltaic cells, lithium batteries, gas sensors, field effect transistors, among other possible applications. The possibility of using unsubstituted Pcs for CNT functionalization is very attractive due to their very moderate cost and easy commercial availability. However, unfortunately, the deposition of unsubstituted Pcs onto nanotube sidewalls through the traditional liquid-phase protocols turns to be very problematic due to extremely poor solubility of Pcs. On the other hand, unsubstituted free-base H₂Pc phthalocyanine ligand, as well as many of its transition metal complexes, exhibit very high thermal stability and considerable volatility under reduced pressure, which opens the possibility for their physical vapor deposition onto solid surfaces, including nanotube sidewalls. In the present work, we show the possibility of simple, fast and efficient noncovalent functionalization of single-walled carbon nanotubes (SWNTs) with a series of 3d metal(II) phthalocyanines Me(II)Pc, where Me= Co, Ni, Cu, and Zn. The functionalization can be performed in a temperature range of 400-500 °C under moderate vacuum and requires about 2-3 h only. The functionalized materials obtained were characterized by means of Fourier-transform infrared (FTIR), Raman, UV-visible and energy-dispersive X-ray spectroscopy (EDS), scanning and transmission electron microscopy (SEM and TEM, respectively) and thermogravimetric analysis (TGA). TGA suggested that Me(II)Pc weight content is 30%, 17% and 35% for NiPc, CuPc, and ZnPc, respectively (CoPc exhibited anomalous thermal decomposition behavior). The above values are consistent with those estimated from EDS spectra, namely, of 24-39%, 27-36% and 27-44% for CoPc, CuPc, and ZnPc, respectively. A strong increase in intensity of D band in the Raman spectra of SWNT‒Me(II)Pc hybrids, as compared to that of pristine nanotubes, implies very strong interactions between Pc molecules and SWNT sidewalls. Very high absolute values of binding energies of 32.46-37.12 kcal/mol and the highest occupied and lowest unoccupied molecular orbital (HOMO and LUMO, respectively) distribution patterns, calculated with density functional theory by using Perdew-Burke-Ernzerhof general gradient approximation correlation functional in combination with the Grimme’s empirical dispersion correction (PBE-D) and the double numerical basis set (DNP), also suggested that the interactions between Me(II) phthalocyanines and nanotube sidewalls are very strong. The authors thank the National Autonomous University of Mexico (grant DGAPA-IN200516) and the National Council of Science and Technology of Mexico (CONACYT, grant 250655) for financial support. The authors are also grateful to Dr. Natalia Alzate-Carvajal (CCADET of UNAM), Eréndira Martínez (IF of UNAM) and Iván Puente-Lee (Faculty of Chemistry of UNAM) for technical assistance with FTIR, TGA measurements, and TEM imaging, respectively.

Keywords: carbon nanotubes, functionalization, gas-phase, metal(II) phthalocyanines

Procedia PDF Downloads 101
141 The Development of Wind Energy and Its Social Acceptance: The Role of Income Received by Wind Farm Owners, the Case of Galicia, Northwest Spain

Authors: X. Simon, D. Copena, M. Montero

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The last decades have witnessed a significant increase in renewable energy, especially wind energy, to achieve sustainable development. Specialized literature in this field has carried out interesting case studies to extensively analyze both the environmental benefits of this energy and its social acceptance. However, to the best of our knowledge, work to date makes no analysis of the role of private owners of lands with wind potential within a broader territory of strong wind implantation, nor does it estimate their economic incomes relating them to social acceptance. This work fills this gap by focusing on Galicia, territory housing over 4,000 wind turbines and almost 3,400 MW of power. The main difficulty in getting this financial information is that it is classified, not public. We develop methodological techniques (semi- structured interviews and work groups), inserted within the Participatory Research, to overcome this important obstacle. In this manner, the work directly compiles qualitative and quantitative information on the processes as well as the economic results derived from implementing wind energy in Galicia. During the field work, we held 106 semi-structured interviews and 32 workshops with owners of lands occupied by wind farms. The compiled information made it possible to create the socioeconomic database on wind energy in Galicia (SDWEG). This database collects a diversity of quantitative and qualitative information and contains economic information on the income received by the owners of lands occupied by wind farms. In the Galician case, regulatory framework prevented local participation under the community wind farm formula. The possibility of local participation in the new energy model narrowed down to companies wanting to install a wind farm and demanding land occupation. The economic mechanism of local participation begins here, thus explaining the level of acceptance of wind farms. Land owners can receive significant income given that these payments constitute an important source of economic resources, favor local economic activity, allow rural areas to develop productive dynamism projects and improve the standard of living of rural inhabitants. This work estimates that land owners in Galicia perceive about 10 million euros per year in total wind revenues. This represents between 1% and 2% of total wind farm invoicing. On the other hand, relative revenues (Euros per MW), far from the amounts reached in other spaces, show enormous payment variability. This signals the absence of a regulated market, the predominance of partial agreements, and the existence of asymmetric positions between owners and developers. Sustainable development requires the replacement of conventional technologies by low environmental impact technologies, especially those that emit less CO₂. However, this new paradigm also requires rural owners to participate in the income derived from the structural transformation processes linked to sustainable development. This paper demonstrates that regulatory framework may contribute to increasing sustainable technologies with high social acceptance without relevant local economic participation.

Keywords: regulatory framework, social acceptance, sustainable development, wind energy, wind income for landowners

Procedia PDF Downloads 124
140 Possible Involvement of DNA-methyltransferase and Histone Deacetylase in the Regulation of Virulence Potential of Acanthamoeba castellanii

Authors: Yi H. Wong, Li L. Chan, Chee O. Leong, Stephen Ambu, Joon W. Mak, Priyadashi S. Sahu

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Background: Acanthamoeba is a free-living opportunistic protist which is ubiquitously distributed in the environment. Virulent Acanthamoeba can cause fatal encephalitis in immunocompromised patients and potential blinding keratitis in immunocompetent contact lens wearers. Approximately 24 species have been identified but only the A. castellanii, A. polyphaga and A. culbertsoni are commonly associated with human infections. Until to date, the precise molecular basis for Acanthamoeba pathogenesis remains unclear. Previous studies reported that Acanthamoeba virulence can be diminished through prolonged axenic culture but revived through serial mouse passages. As no clear explanation on this reversible pathogenesis is established, hereby, we postulate that the epigenetic regulators, DNA-methyltransferases (DNMT) and histone-deacetylases (HDAC), could possibly be involved in granting the virulence plasticity of Acanthamoeba spp. Methods: Four rounds of mouse passages were conducted to revive the virulence potential of the virulence-attenuated Acanthamoeba castellanii strain (ATCC 50492). Briefly, each mouse (n=6/group) was inoculated intraperitoneally with Acanthamoebae cells (2x 105 trophozoites/mouse) and incubated for 2 months. Acanthamoebae cells were isolated from infected mouse organs by culture method and subjected to subsequent mouse passage. In vitro cytopathic, encystment and gelatinolytic assays were conducted to evaluate the virulence characteristics of Acanthamoebae isolates for each passage. PCR primers which targeted on the 2 members (DNMT1 and DNMT2) and 5 members (HDAC1 to 5) of the DNMT and HDAC gene families respectively were custom designed. Quantitative real-time PCR (qPCR) was performed to detect and quantify the relative expression of the two gene families in each Acanthamoeba isolates. Beta-tubulin of A. castellanii (Genbank accession no: XP_004353728) was included as housekeeping gene for data normalisation. PCR mixtures were also analyzed by electrophoresis for amplicons detection. All statistical analyses were performed using the paired one-tailed Student’s t test. Results: Our pathogenicity tests showed that the virulence-reactivated Acanthamoeba had a higher degree of cytopathic effect on vero cells, a better resistance to encystment challenge and a higher gelatinolytic activity which was catalysed by serine protease. qPCR assay showed that DNMT1 expression was significantly higher in the virulence-reactivated compared to the virulence-attenuated Acanthamoeba strain (p ≤ 0.01). The specificity of primers which targeted on DNMT1 was confirmed by sequence analysis of PCR amplicons, which showed a 97% similarity to the published DNA-methyltransferase gene of A. castellanii (GenBank accession no: XM_004332804.1). Out of the five primer pairs which targeted on the HDAC family genes, only HDAC4 expression was significantly difference between the two variant strains. In contrast to DNMT1, HDAC4 expression was much higher in the virulence-attenuated Acanthamoeba strain. Conclusion: Our mouse passages had successfully restored the virulence of the attenuated strain. Our findings suggested that DNA-methyltransferase (DNMT1) and histone deacetylase (HDAC4) expressions are associated with virulence potential of Acanthamoeba spp.

Keywords: acanthamoeba, DNA-methyltransferase, histone deacetylase, virulence-associated proteins

Procedia PDF Downloads 264
139 The Return of the Rejected Kings: A Comparative Study of Governance and Procedures of Standards Development Organizations under the Theory of Private Ordering

Authors: Olia Kanevskaia

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Standardization has been in the limelight of numerous academic studies. Typically described as ‘any set of technical specifications that either provides or is intended to provide a common design for a product or process’, standards do not only set quality benchmarks for products and services, but also spur competition and innovation, resulting in advantages for manufacturers and consumers. Their contribution to globalization and technology advancement is especially crucial in the Information and Communication Technology (ICT) and telecommunications sector, which is also characterized by a weaker state-regulation and expert-based rule-making. Most of the standards developed in that area are interoperability standards, which allow technological devices to establish ‘invisible communications’ and to ensure their compatibility and proper functioning. This type of standard supports a large share of our daily activities, ranging from traffic coordination by traffic lights to the connection to Wi-Fi networks, transmission of data via Bluetooth or USB and building the network architecture for the Internet of Things (IoT). A large share of ICT standards is developed in the specialized voluntary platforms, commonly referred to as Standards Development Organizations (SDOs), which gather experts from various industry sectors, private enterprises, governmental agencies and academia. The institutional architecture of these bodies can vary from semi-public bodies, such as European Telecommunications Standards Institute (ETSI), to industry-driven consortia, such as the Internet Engineering Task Force (IETF). The past decades witnessed a significant shift of standard setting to those institutions: while operating independently from the states regulation, they offer a rather informal setting, which enables fast-paced standardization and places technical supremacy and flexibility of standards above other considerations. Although technical norms and specifications developed by such nongovernmental platforms are not binding, they appear to create significant regulatory impact. In the United States (US), private voluntary standards can be used by regulators to achieve their policy objectives; in the European Union (EU), compliance with harmonized standards developed by voluntary European Standards Organizations (ESOs) can grant a product a free-movement pass. Moreover, standards can de facto manage the functioning of the market when other regulative alternatives are not available. Hence, by establishing (potentially) mandatory norms, SDOs assume regulatory functions commonly exercised by States and shape their own legal order. The purpose of this paper is threefold: First, it attempts to shed some light on SDOs’ institutional architecture, focusing on private, industry-driven platforms and comparing their regulatory frameworks with those of formal organizations. Drawing upon the relevant scholarship, the paper then discusses the extent to which the formulation of technological standards within SDOs constitutes a private legal order, operating in the shadow of governmental regulation. Ultimately, this contribution seeks to advise whether a state-intervention in industry-driven standard setting is desirable, and whether the increasing regulatory importance of SDOs should be addressed in legislation on standardization.

Keywords: private order, standardization, standard-setting organizations, transnational law

Procedia PDF Downloads 141
138 Spinetoram10% WG+Sulfoxaflor 30% WG: A Promising Green Chemistry to Manage Pest Complex in Bt Cotton

Authors: Siddharudha B. Patil

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Cotton is a premier commercial fibre crop of India subjected to ravages of insect pests. Sucking pests viz thrips, Thrips tabaci,(lind) leaf hopper Amrsca devastance,(dist) miridbug, Poppiocapsidea beseratense (Dist) and bollworms continue to inflict damage Bt Cotton right from seeding stage. Their infestation impact cotton yield to an extent of 30-40 percent. Chemical control is still adoptable as one of the techniques for combating these pests. Presently, growers have many challenges in selecting effective chemicals which fit in with an integrated pest management. Spinetoram has broad spectrum with excellent insecticidal activity against both sucking pests and bollworms. Hence, it is expected to make a great contribution to stable production and quality improvement of agricultural products. Spinetoram is a derivative of biologically active substances (Spinosyns) produced by soil actinomycetes, Saccharopolypara spinosa which is semi synthetic active ingredient representing Spinosyn chemical class of insecticide and has demonstrated higher level of efficacy with reduced risk on beneficial arthropods. The efforts were made in the present study to test the efficacy of Spinetoram against sucking pests and bollworms in comparison with other insecticides in Bt Cotton under field condition. Field experiment was laid out during 2013-14 and 2014-15 at Agricultural Research station Dharwad (Karnataka-India) in a randomized block design comprising eight treatments and three replications. Bt cotton genotype, Bunny BG-II was sown in a plot size of 5.4 m x5.4 m. Recommend agronomical practices were followed. The Spinetoram 12% SC alone and incombination with sulfaxaflore with varied dosages against pest complex was tested. Performance was compared with Spinosad 45% SC and thiamethoxam 25% WG. The results of consecutive seasons revealed that nonsignificant difference in thrips and leafhopper population and varied significantly after 3 days of imposition. Among the treatments, combiproduct, Spinetoram 10%WG + Sulfoxaflor 30% WG@ 140 gai/ha registered lowest population of thrips (3.91/3 leaves) and leaf hoppers (1.08/3 leaves) followed by its lower dosages viz 120 gai/ha (4.86/3 leaves and 1.14/3 leaves of thrips and leaf hoppers, respectively) and 100 gai/ha (6.02 and 1.23./3 leaves of thrips and leaf hoppers respectively) being at par, significantly superior to rest of the treatments. On the contrary, the population of thrips, leaf hopper and miridbugs in untreated control was on higher side. Similarly the higher dosage of Spinetoram 10% WG+ Sulfoxaflor 30% WG (140 gai/ha) proved its bioefficacy by registering lowest miridbug incidence of 1.70/25 squares, followed by its lower dosage (1.78 and 1.83/25 squares respectively) Further observation made on bollworms incidence revealed that the higher dosage of Spinetoram 10% WG+Sulfoxaflor 30% WG (140 gai/ha) registered lowest percentage of boll damage (7.22%), more number of good opened bolls (36.89/plant) and higher seed cotton yield (19.45q/ha) followed by rest of its lower dosages, Spinetoram 12% SC alone and Spinosad 45% SC being at par significantly superior to rest of the treatments. However, significantly higher boll damage (15.13%) and lower seed cotton yield (14.45 q/ha) was registered in untreated control. Thus Spinetoram10% WG+Sulfoxaflor 30% WG can be a promising option for pest management in Bt Cotton.

Keywords: Spinetoram10% WG+Sulfoxaflor 30% WG, sucking pests, bollworms, Bt cotton, management

Procedia PDF Downloads 218
137 Single Cell Analysis of Circulating Monocytes in Prostate Cancer Patients

Authors: Leander Van Neste, Kirk Wojno

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The innate immune system reacts to foreign insult in several unique ways, one of which is phagocytosis of perceived threats such as cancer, bacteria, and viruses. The goal of this study was to look for evidence of phagocytosed RNA from tumor cells in circulating monocytes. While all monocytes possess phagocytic capabilities, the non-classical CD14+/FCGR3A+ monocytes and the intermediate CD14++/FCGR3A+ monocytes most actively remove threatening ‘external’ cellular materials. Purified CD14-positive monocyte samples from fourteen patients recently diagnosed with clinically localized prostate cancer (PCa) were investigated by single-cell RNA sequencing using the 10X Genomics protocol followed by paired-end sequencing on Illumina’s NovaSeq. Similarly, samples were processed and used as controls, i.e., one patient underwent biopsy but was found not to harbor prostate cancer (benign), three young, healthy men, and three men previously diagnosed with prostate cancer that recently underwent (curative) radical prostatectomy (post-RP). Sequencing data were mapped using 10X Genomics’ CellRanger software and viable cells were subsequently identified using CellBender, removing technical artifacts such as doublets and non-cellular RNA. Next, data analysis was performed in R, using the Seurat package. Because the main goal was to identify differences between PCa patients and ‘control’ patients, rather than exploring differences between individual subjects, the individual Seurat objects of all 21 patients were merged into one Seurat object per Seurat’s recommendation. Finally, the single-cell dataset was normalized as a whole prior to further analysis. Cell identity was assessed using the SingleR and cell dex packages. The Monaco Immune Data was selected as the reference dataset, consisting of bulk RNA-seq data of sorted human immune cells. The Monaco classification was supplemented with normalized PCa data obtained from The Cancer Genome Atlas (TCGA), which consists of bulk RNA sequencing data from 499 prostate tumor tissues (including 1 metastatic) and 52 (adjacent) normal prostate tissues. SingleR was subsequently run on the combined immune cell and PCa datasets. As expected, the vast majority of cells were labeled as having a monocytic origin (~90%), with the most noticeable difference being the larger number of intermediate monocytes in the PCa patients (13.6% versus 7.1%; p<.001). In men harboring PCa, 0.60% of all purified monocytes were classified as harboring PCa signals when the TCGA data were included. This was 3-fold, 7.5-fold, and 4-fold higher compared to post-RP, benign, and young men, respectively (all p<.001). In addition, with 7.91%, the number of unclassified cells, i.e., cells with pruned labels due to high uncertainty of the assigned label, was also highest in men with PCa, compared to 3.51%, 2.67%, and 5.51% of cells in post-RP, benign, and young men, respectively (all p<.001). It can be postulated that actively phagocytosing cells are hardest to classify due to their dual immune cell and foreign cell nature. Hence, the higher number of unclassified cells and intermediate monocytes in PCa patients might reflect higher phagocytic activity due to tumor burden. This also illustrates that small numbers (~1%) of circulating peripheral blood monocytes that have interacted with tumor cells might still possess detectable phagocytosed tumor RNA.

Keywords: circulating monocytes, phagocytic cells, prostate cancer, tumor immune response

Procedia PDF Downloads 136
136 The Development of Congeneric Elicited Writing Tasks to Capture Language Decline in Alzheimer Patients

Authors: Lise Paesen, Marielle Leijten

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People diagnosed with probable Alzheimer disease suffer from an impairment of their language capacities; a gradual impairment which affects both their spoken and written communication. Our study aims at characterising the language decline in DAT patients with the use of congeneric elicited writing tasks. Within these tasks, a descriptive text has to be written based upon images with which the participants are confronted. A randomised set of images allows us to present the participants with a different task on every encounter, thus allowing us to avoid a recognition effect in this iterative study. This method is a revision from previous studies, in which participants were presented with a larger picture depicting an entire scene. In order to create the randomised set of images, existing pictures were adapted following strict criteria (e.g. frequency, AoA, colour, ...). The resulting data set contained 50 images, belonging to several categories (vehicles, animals, humans, and objects). A pre-test was constructed to validate the created picture set; most images had been used before in spoken picture naming tasks. Hence the same reaction times ought to be triggered in the typed picture naming task. Once validated, the effectiveness of the descriptive tasks was assessed. First, the participants (n=60 students, n=40 healthy elderly) performed a typing task, which provided information about the typing speed of each individual. Secondly, two descriptive writing tasks were carried out, one simple and one complex. The simple task contains 4 images (1 animal, 2 objects, 1 vehicle) and only contains elements with high frequency, a young AoA (<6 years), and fast reaction times. Slow reaction times, a later AoA (≥ 6 years) and low frequency were criteria for the complex task. This task uses 6 images (2 animals, 1 human, 2 objects and 1 vehicle). The data were collected with the keystroke logging programme Inputlog. Keystroke logging tools log and time stamp keystroke activity to reconstruct and describe text production processes. The data were analysed using a selection of writing process and product variables, such as general writing process measures, detailed pause analysis, linguistic analysis, and text length. As a covariate, the intrapersonal interkey transition times from the typing task were taken into account. The pre-test indicated that the new images lead to similar or even faster reaction times compared to the original images. All the images were therefore used in the main study. The produced texts of the description tasks were significantly longer compared to previous studies, providing sufficient text and process data for analyses. Preliminary analysis shows that the amount of words produced differed significantly between the healthy elderly and the students, as did the mean length of production bursts, even though both groups needed the same time to produce their texts. However, the elderly took significantly more time to produce the complex task than the simple task. Nevertheless, the amount of words per minute remained comparable between simple and complex. The pauses within and before words varied, even when taking personal typing abilities (obtained by the typing task) into account.

Keywords: Alzheimer's disease, experimental design, language decline, writing process

Procedia PDF Downloads 252
135 Efficacy of a Social-Emotional Learning Curriculum for Kindergarten and First Grade Students to Improve Social Adjustment within the School Culture

Authors: Ann P. Daunic, Nancy Corbett

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Background and Significance: Researchers emphasize the role that motivation, self-esteem, and self-regulation play in children’s early adjustment to the school culture, including skills such as identifying their own feelings and understanding the feelings of others. As social-emotional growth, academic learning, and successful integration within culture and society are inextricably connected, the Social-Emotional Learning Foundations (SELF) curriculum was designed to integrate social-emotional learning (SEL) instruction within early literacy instruction (specifically, reading) for Kindergarten and first-grade students at risk for emotional and behavioral difficulties. Storybook reading is a typically occurring activity in the primary grades; thus SELF provides an intervention that is both theoretically and practically sound. Methodology: The researchers will report on findings from the first two years of a three-year study funded by the US Department of Education’s Institute of Education Sciences to evaluate the effects of the SELF curriculum versus “business as usual” (BAU). SELF promotes the development of self-regulation by incorporating instructional strategies that support children’s use of SEL related vocabulary, self-talk, and critical thinking. The curriculum consists of a carefully coordinated set of materials and pedagogy designed specifically for primary grade children at early risk for emotional and behavioral difficulties. SELF lessons (approximately 50 at each grade level) are organized around 17 SEL topics within five critical competencies. SELF combines whole-group (the first in each topic) and small-group lessons (the 2nd and 3rd in each topic) to maximize opportunities for teacher modeling and language interactions. The researchers hypothesize that SELF offers a feasible and substantial opportunity within the classroom setting to provide a small-group social-emotional learning intervention integrated with K-1 literacy-related instruction. Participating target students (N = 876) were identified by their teachers as potentially at risk for emotional or behavioral issues. These students were selected from 122 Kindergarten and 100 first grade classrooms across diverse school districts in a southern state in the US. To measure the effectiveness of the SELF intervention, the researchers asked teachers to complete assessments related to social-emotional learning and adjustment to the school culture. A social-emotional learning related vocabulary assessment was administered directly to target students receiving small-group instruction. Data were analyzed using a 3-level MANOVA model with full information maximum likelihood to estimate coefficients and test hypotheses. Major Findings: SELF had significant positive effects on vocabulary, knowledge, and skills associated with social-emotional competencies, as evidenced by results from the measures administered. Effect sizes ranged from 0.41 for group (SELF vs. BAU) differences in vocabulary development to 0.68 for group differences in SEL related knowledge. Conclusion: Findings from two years of data collection indicate that SELF improved outcomes related to social-emotional learning and adjustment to the school culture. This study thus supports the integration of SEL with literacy instruction as a feasible and effective strategy to improve outcomes for K-1 students at risk for emotional and behavioral difficulties.

Keywords: Socio-cultural context for learning, social-emotional learning, social skills, vocabulary development

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134 The Shadowy History of Berlin Underground: 1939-45/Der Schattenmann: Tagebuchaufzeichnungen 1938-1945

Authors: Christine Wiesenthal

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This paper asks how to read a particularly vexed and complicated life writing text. For over half a century, the wartime journals of Ruth Andreas Friedrich (1901-1977) circulated as among a handful of more or less authoritative and “authentic” first-hand accounts of German resistance under Hitler. A professional journalist, Andreas Friedrich is remembered today largely through her publications at the war’s end, which appeared in English as Berlin Underground (published by Henry Holt in 1947), just before their publication in Germany as Der Schattenmann “The Shadow Man” (also in 1947). A British edition by the now obscure Latimer House Limited (London) followed in 1948; it is based closely on but is not identical to, the Henry Holt American edition, which in turn differs significantly from its German counterpart. Both Berlin Underground and Der Schattenmann figure Andreas-Friedrich as a key figure in an anti-fascist cell that operated in Berlin under the code name “Uncle Emil,” and provide a riveting account of political terror, opportunism, and dissent under the Nazi regime. Recent scholars have, however, begun to raise fascinating and controversial questions about Andreas-Friedrich’s own writing/reconstruction process in compiling the journals and about her highly selective curatorial role and claims. The apparent absence of any surviving original manuscript for Andreas-Friedrich’s journals amplifies the questions around them. Crucially, so too does the role of the translator of the English editions of Berlin Underground, the enigmatic June Barrows Mussey, a subject that has thus far gone virtually unnoticed and which this paper will focus on. Mussey, a prolific American translator, simultaneously cultivated a career as a professional magician, publishing a number of books on that subject under the alias Henry Hay. While the record indicates that Mussey attempted to compartmentalize his professional life, research into the publishing and translation history of Berlin Underground suggests that the two roles converge in the fact of the translator’s invisibility, by effacing the traces of his own hand and leaving unmarked his own significant textual interventions, Mussey, in effect, edited, abridged, and altered Andreas Friedrich’s journals for the second time. In fact, it could be said that while the fictitious “Uncle Emil” is positioned as “the shadow man” of the German edition, Mussey himself also emerges as precisely that in the English rendering of the journals. The implications of Mussey’s translation of Andreas Friedrich’s journals are one of the most important un-examined gaps in the shadowy publishing history of Berlin Underground, a history full of “tricks” (Mussey’s words) and illusions of transparency. Based largely on archival research of unpublished materials and methods of close reading and comparative analysis, this study will seek to convey some preliminary insights and exploratory work and frame questions toward what is ultimately envisioned as an experimental project in poetic historiography. As this work is still in the early stages, it would be especially welcome to have the opportunity provided by this conference to connect with a community of life writing colleagues who might help think through some of the challenges and possibilities that lie ahead.

Keywords: women’s wartime diaries, translation studies, auto/biographical theory, politics of life writing

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133 Urban Dynamics Modelling of Mixed Land Use for Sustainable Urban Development in Indian Context

Authors: Rewati Raman, Uttam K. Roy

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One of the main adversaries of city planning in present times is the ever-expanding problem of urbanization and the antagonistic issues accompanying it. The prevalent challenges in urbanization such as population growth, urban sprawl, poverty, inequality, pollution, congestion, etc. call for reforms in the urban fabric as well as in planning theory and practice. One of the various paradigms of city planning, land use planning, has been the major instruments for spatial planning of cities and regions in India. Zoning regulation based land use planning in the form of land use and development control plans (LUDCP) and development control regulations (DCR) have been considered mainstream guiding principles in land use planning for decades. In spite of many advantages of such zoning based regulations, over a period of time, it has been critiqued by scholars for its own limitations of isolation and lack of vitality, inconvenience in business in terms of proximity to residence and low operating cost, unsuitable environment for small investments, higher travel distance for facilities, amenities and thereby higher expenditure, safety issues etc. Mixed land use has been advocated as a tool to avoid such limitations in city planning by researchers. In addition, mixed land use can offer many advantages like housing variety and density, the creation of an economic blend of compatible land use, compact development, stronger neighborhood character, walkability, and generation of jobs, etc. Alternatively, the mixed land use beyond a suitable balance of use can also bring disadvantages like traffic congestion, encroachments, very high-density housing leading to a slum like condition, parking spill out, non-residential uses operating on residential premises paying less tax, chaos hampering residential privacy, pressure on existing infrastructure facilities, etc. This research aims at studying and outlining the various challenges and potentials of mixed land use zoning, through modeling tools, as a competent instrument for city planning in lieu of the present urban scenario. The methodology of research adopted in this paper involves the study of a mixed land use neighborhood in India, identification of indicators and parameters related to its extent and spatial pattern and the subsequent use of system dynamics as a modeling tool for simulation. The findings from this analysis helped in identifying the various advantages and challenges associated with the dynamic nature of a mixed use urban settlement. The results also confirmed the hypothesis that mixed use neighborhoods are catalysts for employment generation, socioeconomic gains while improving vibrancy, health, safety, and security. It is also seen that certain challenges related to chaos, lack of privacy and pollution prevail in mixed use neighborhoods, which can be mitigated by varying the percentage of mixing as per need, ensuring compatibility of adjoining use, institutional interventions in the form of policies, neighborhood micro-climatic interventions, etc. Therefore this paper gives a consolidated and holistic framework and quantified outcome pertaining to the extent and spatial pattern of mixed land use that should be adopted to ensure sustainable urban planning.

Keywords: mixed land use, sustainable development, system dynamics analysis, urban dynamics modelling

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132 Drones, Rebels and Bombs: Explaining the Role of Private Security and Expertise in a Post-piratical Indian Ocean

Authors: Jessica Kate Simonds

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The last successful hijacking perpetrated by Somali pirates in 2012 represented a critical turning point for the identity and brand of Indian Ocean (IO) insecurity, coined in this paper as the era of the post-piratical. This paper explores the broadening of the PMSC business model to account and contribute to the design of a new IO security environment that prioritises foreign and insurgency drone activity and Houthi rebel operations as the main threat to merchant shipping in the post-2012 era. This study is situated within a longer history of analysing maritime insecurity and also contributes a bespoke conceptual framework that understands the sea as a space that is produced and reproduced relative to existing and emerging threats to merchant shipping based on bespoke models of information sharing and intelligence acquisition. This paper also makes a prominent empirical contribution by drawing on a post-positivist methodology, data drawn from original semi-structured interviews with senior maritime insurers and active merchant seafarers that is triangulated with industry-produced guidance such as the BMP series as primary data sources. Each set is analysed through qualitative discourse and content analysis and supported by the quantitative data sets provided by the IMB Piracy Reporting center and intelligence networks. This analysis reveals that mechanisms such as the IGP&I Maritime Security Committee and intelligence divisions of PMSC’s have driven the exchanges of knowledge between land and sea and thus the reproduction of the maritime security environment through new regulations and guidance to account dones, rebels and bombs as the key challenges in the IO, beyond piracy. A contribution of this paper is the argument that experts who may not be in the highest-profile jobs are the architects of maritime insecurity based on their detailed knowledge and connections to vessels in transit. This paper shares the original insights of those who have served in critical decision making spaces to demonstrate that the development and refinement of industry produced deterrence guidance that has been accredited to the mitigation of piracy, have shaped new editions such as BMP 5 that now serve to frame a new security environment that prioritises the mitigation of risks from drones and WBEID’s from both state and insurgency risk groups. By highlighting the experiences and perspectives of key players on both land and at sea, the key finding of this paper is outlining that as pirates experienced a financial boom by profiteering from their bespoke business model during the peak of successful hijackings, the private security market encountered a similar level of financial success and guaranteed risk environment in which to prospect business. Thus, the reproduction of the Indian Ocean as a maritime security environment reflects a new found purpose for PMSC’s as part of the broader conglomerate of maritime insurers, regulators, shipowners and managers who continue to redirect the security consciousness and IO brand of insecurity.

Keywords: maritime security, private security, risk intelligence, political geography, international relations, political economy, maritime law, security studies

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131 The Preliminary Exposition of Soil Biological Activity, Microbial Diversity and Morpho-Physiological Indexes of Cucumber under Interactive Effect of Allelopathic Garlic Stalk: A Short-Term Dynamic Response in Replanted Alkaline Soil

Authors: Ahmad Ali, Muhammad Imran Ghani, Haiyan Ding, Zhihui Cheng, Muhammad Iqbal

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Background and Aims: In recent years, protected cultivation trend, especially in the northern parts of China, spread dynamically where production area, structure, and crops diversity have expanded gradually under plastic greenhouse vegetable cropping (PGVC) system. Under this growing system, continuous monoculture with excessive synthetic fertilizers inputs are common cultivation practices frequently adopted by commercial producers. Such long-term cumulative wild exercise year after year sponsor the continuous cropping obstacles in PGVC soil, which have greatly threatened the regional soil eco-sustainability and further impose the continuous assault on soil ecological diversity leading to the exhaustion of agriculture productivity. The aim of this study was to develop new allelopathic insights by exploiting available biological resources in the favor of sustainable PGVC to illuminate the continuous obstacle factors in plastic greenhouse. Method: A greenhouse study was executed under plastic tunnel located at the Horticulture Experimental Station of the College of Horticulture, Northwest A&F University, Yangling, Shaanxi Province, one of the prominent regions for intensive commercial PGVC in China. Post-harvest garlic residues (stalk, leaves) mechanically smashed, homogenized into powder size and incorporated at the ratio of 1:100; 3:100; 5:100 as a soil amendment in a replanted soil that have been used for continuous cucumber monoculture for 7 years (annually double cropping system in a greenhouse). Results: Incorporated C-rich garlic stalk significantly influenced the soil condition through various ways; organic matter decomposition and mineralization, moderately adjusted the soil pH, enhanced the soil nutrient availability, increased enzymatic activities, and promoted 20% more cucumber yield in short-time. Using Illumina MiSeq sequencing analysis of bacterial 16S rRNA and fungal 18S rDNA genes, the current study revealed that addition of garlic stalk/residue could also improve the microbial abundance and community composition in extensively exploited soil, and contributed in soil functionality, caused prosper changes in soil characteristics, reinforced to good crop yield. Conclusion: Our study provided evidence that addition of garlic stalk as soil fertility amendment is a feasible, cost-effective and efficient resource utilization way for renovation of degraded soil health, ameliorate soil quality components and improve ecological environment in short duration. Our study may provide a better scientific understanding for efficient crop residue management typically from allelopathic source.

Keywords: garlic stalk, microbial community dynamics, plant growth, soil amendment, soil-plant system

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130 Effect of Velocity-Slip in Nanoscale Electroosmotic Flows: Molecular and Continuum Transport Perspectives

Authors: Alper T. Celebi, Ali Beskok

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Electroosmotic (EO) slip flows in nanochannels are investigated using non-equilibrium molecular dynamics (MD) simulations, and the results are compared with analytical solution of Poisson-Boltzmann and Stokes (PB-S) equations with slip contribution. The ultimate objective of this study is to show that well-known continuum flow model can accurately predict the EO velocity profiles in nanochannels using the slip lengths and apparent viscosities obtained from force-driven flow simulations performed at various liquid-wall interaction strengths. EO flow of aqueous NaCl solution in silicon nanochannels are simulated under realistic electrochemical conditions within the validity region of Poisson-Boltzmann theory. A physical surface charge density is determined for nanochannels based on dissociations of silanol functional groups on channel surfaces at known salt concentration, temperature and local pH. First, we present results of density profiles and ion distributions by equilibrium MD simulations, ensuring that the desired thermodynamic state and ionic conditions are satisfied. Next, force-driven nanochannel flow simulations are performed to predict the apparent viscosity of ionic solution between charged surfaces and slip lengths. Parabolic velocity profiles obtained from force-driven flow simulations are fitted to a second-order polynomial equation, where viscosity and slip lengths are quantified by comparing the coefficients of the fitted equation with continuum flow model. Presence of charged surface increases the viscosity of ionic solution while the velocity-slip at wall decreases. Afterwards, EO flow simulations are carried out under uniform electric field for different liquid-wall interaction strengths. Velocity profiles present finite slips near walls, followed with a conventional viscous flow profile in the electrical double layer that reaches a bulk flow region in the center of the channel. The EO flow enhances with increased slip at the walls, which depends on wall-liquid interaction strength and the surface charge. MD velocity profiles are compared with the predictions from analytical solutions of the slip modified PB-S equation, where the slip length and apparent viscosity values are obtained from force-driven flow simulations in charged silicon nano-channels. Our MD results show good agreements with the analytical solutions at various slip conditions, verifying the validity of PB-S equation in nanochannels as small as 3.5 nm. In addition, the continuum model normalizes slip length with the Debye length instead of the channel height, which implies that enhancement in EO flows is independent of the channel height. Further MD simulations performed at different channel heights also shows that the flow enhancement due to slip is independent of the channel height. This is important because slip enhanced EO flow is observable even in micro-channels experiments by using a hydrophobic channel with large slip and high conductivity solutions with small Debye length. The present study provides an advanced understanding of EO flows in nanochannels. Correct characterization of nanoscale EO slip flow is crucial to discover the extent of well-known continuum models, which is required for various applications spanning from ion separation to drug delivery and bio-fluidic analysis.

Keywords: electroosmotic flow, molecular dynamics, slip length, velocity-slip

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129 Predicting Career Adaptability and Optimism among University Students in Turkey: The Role of Personal Growth Initiative and Socio-Demographic Variables

Authors: Yagmur Soylu, Emir Ozeren, Erol Esen, Digdem M. Siyez, Ozlem Belkis, Ezgi Burc, Gülce Demirgurz

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The aim of the study is to determine the predictive power of personal growth initiative, socio-demographic variables (such as sex, grade, and working condition) on career adaptability and optimism of bachelor students in Dokuz Eylul University in Turkey. According to career construction theory, career adaptability is viewed as a psychosocial construct, which refers to an individual’s resources for dealing with current and expected tasks, transitions and traumas in their occupational roles. Career optimism is defined as positive results for future career development of individuals in the expectation that it will achieve or to put the emphasis on the positive aspects of the event and feel comfortable about the career planning process. Personal Growth Initiative (PGI) is defined as being proactive about one’s personal development. Additionally, personal growth is defined as the active and intentional engagement in the process of personal. A study conducted on college students revealed that individuals with high self-development orientation make more effort to discover the requirements of the profession and workspaces than individuals with low levels of personal development orientation. University life is a period that social relations and the importance of academic activities are increased, the students make efforts to progress through their career paths and it is also an environment that offers opportunities to students for their self-realization. For these reasons, personal growth initiative is potentially an important variable which has a key role for an individual during the transition phase from university to the working life. Based on the review of the literature, it is expected that individual’s personal growth initiative, sex, grade, and working condition would significantly predict one’s career adaptability. In the relevant literature, it can be seen that there are relatively few studies available on the career adaptability and optimism of university students. Most of the existing studies have been carried out with limited respondents. In this study, the authors aim to conduct a comprehensive research with a large representative sample of bachelor students in Dokuz Eylul University, Izmir, Turkey. By now, personal growth initiative and career development constructs have been predominantly discussed in western contexts where individualistic tendencies are likely to be seen. Thus, the examination of the same relationship within the context of Turkey where collectivistic cultural characteristics can be more observed is expected to offer valuable insights and provide an important contribution to the literature. The participants in this study were comprised of 1500 undergraduate students being included from thirteen faculties in Dokuz Eylul University. Stratified and random sampling methods were adopted for the selection of the participants. The Personal Growth Initiative Scale-II and Career Futures Inventory were used as the major measurement tools. In data analysis stage, several statistical analysis concerning the regression analysis, one-way ANOVA and t-test will be conducted to reveal the relationships of the constructs under investigation. At the end of this project, we will be able to determine the level of career adaptability and optimism of university students at varying degrees so that a fertile ground is likely to be created to carry out several intervention techniques to make a contribution to an emergence of a healthier and more productive youth generation in psycho-social sense.

Keywords: career optimism, career adaptability, personal growth initiative, university students

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128 3D Printing of Polycaprolactone Scaffold with Multiscale Porosity Via Incorporation of Sacrificial Sucrose Particles

Authors: Mikaela Kutrolli, Noah S. Pereira, Vanessa Scanlon, Mohamadmahdi Samandari, Ali Tamayol

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Bone tissue engineering has drawn significant attention and various biomaterials have been tested. Polymers such as polycaprolactone (PCL) offer excellent biocompatibility, reasonable mechanical properties, and biodegradability. However, PCL scaffolds suffer a critical drawback: a lack of micro/mesoporosity, affecting cell attachment, tissue integration, and mineralization. It also results in a slow degradation rate. While 3D-printing has addressed the issue of macroporosity through CAD-guided fabrication, PCL scaffolds still exhibit poor smaller-scale porosity. To overcome this, we generated composites of PCL, hydroxyapatite (HA), and powdered sucrose (PS). The latter serves as a sacrificial material to generate porous particles after sucrose dissolution. Additionally, we have incorporated dexamethasone (DEX) to boost the PCL osteogenic properties. The resulting scaffolds maintain controlled macroporosity from the lattice print structure but also develop micro/mesoporosity within PCL fibers when exposed to aqueous environments. The study involved mixing PS into solvent-dissolved PCL in different weight ratios of PS to PCL (70:30, 50:50, and 30:70 wt%). The resulting composite was used for 3D printing of scaffolds at room temperature. Printability was optimized by adjusting pressure, speed, and layer height through filament collapse and fusion test. Enzymatic degradation, porogen leaching, and DEX release profiles were characterized. Physical properties were assessed using wettability, SEM, and micro-CT to quantify the porosity (percentage, pore size, and interconnectivity). Raman spectroscopy was used to verify the absence of sugar after leaching. Mechanical characteristics were evaluated via compression testing before and after porogen leaching. Bone marrow stromal cells (BMSCs) behavior in the printed scaffolds was studied by assessing viability, metabolic activity, osteo-differentiation, and mineralization. The scaffolds with a 70% sugar concentration exhibited superior printability and reached the highest porosity of 80%, but performed poorly during mechanical testing. A 50% PS concentration demonstrated a 70% porosity, with an average pore size of 25 µm, favoring cell attachment. No trace of sucrose was found in Raman after leaching the sugar for 8 hours. Water contact angle results show improved hydrophilicity as the sugar concentration increased, making the scaffolds more conductive to cell adhesion. The behavior of bone marrow stromal cells (BMSCs) showed positive viability and proliferation results with an increasing trend of mineralization and osteo-differentiation as the sucrose concentration increased. The addition of HA and DEX also promoted mineralization and osteo-differentiation in the cultures. The integration of PS as porogen at a concentration of 50%wt within PCL scaffolds presents a promising approach to address the poor cell attachment and tissue integration issues of PCL in bone tissue engineering. The method allows for the fabrication of scaffolds with tunable porosity and mechanical properties, suitable for various applications. The addition of HA and DEX further enhanced the scaffolds. Future studies will apply the scaffolds in an in-vivo model to thoroughly investigate their performance.

Keywords: bone, PCL, 3D printing, tissue engineering

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127 Light and Scanning Electron Microscopic Studies on Corneal Ontogeny in Buffalo

Authors: M. P. S. Tomar, Neelam Bansal

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Histomorphological, histochemical and scanning electron microscopic observations were recorded in developing cornea of buffalo fetuses. The samples from fetal cornea were collected in appropriate fixative from slaughter house and Veterinary Clinics, GADVASU, Ludhiana. The microscopic slides were stained for detailed histomorphological and histochemical studies. The scanning electron microscopic studies were performed at Electron microscopy & Nanobiology Lab, PAU Ludhiana. In present study, it was observed that, in 36 days (d) fetus, the corneal epithelium was well marked single layered structure which was placed on stroma mesenchyme. Cornea appeared as the continuation of developing sclera. The thickness of cornea and its epithelium increased as well as the epithelium started becoming double layered in 47d fetus at corneo-scleral junction. The corneal thickness in this stage suddenly increased thus easily distinguished from developing sclera. The separation of corneal endothelium from stroma was evident as a single layered epithelium. The stroma possessed numerous fibroblasts in 49d stage eye. Descemet’s membrane was appeared at 52d stage. The limbus area was separated by a depression from the developing cornea in 61d stage. In 65d stage, the Bowman’s layer was more developed. Fibroblasts were arranged parallel to each other as well as parallel to the surface of developing cornea in superficial layers. These fibroblasts and fibers were arranged in wavy pattern in the center of stroma. Corneal epithelium started to be stratified as a double layered epithelium was present in this age of fetal eye. In group II (>120 Days), the corneal epithelium was stratified towards a well marked irido-corneal angle. The stromal fibroblasts followed a complete parallel arrangement in its entire thickness. In full term fetuses, a well developed cornea was observed. It was a fibrous layer which had five distinct layers. From outside to inwards were described as the outer most layer was the 7-8 layered corneal epithelial, subepithelial basement membrane (Bowman’s membrane), substantia propria or stroma, posterior limiting membrane (Descemet’s membrane) and the posterior epithelium (corneal endothelium). The corneal thickness and connective tissue elements were continued to be increased. It was 121.39 + 3.73µ at 36d stage which increased to 518.47 + 4.98 µ in group III fetuses. In fetal life, the basement membrane of corneal epithelium and endothelium depicted strong to intense periodic Acid Schiff’s (PAS) reaction. At the irido-corneal angle, the endothelium of blood vessels was also positive for PAS activity. However, cornea was found mild positive for alcian blue reaction. The developing cornea showed strong reaction for basic proteins in outer epithelium and the inner endothelium layers. Under low magnification scanning electron microscope, cornea showed two types of cells viz. light cells and dark cells. The light cells were smaller in size and had less number of microvilli in their surface than in the dark cells. Despite these surface differences between light and dark cells, the corneal surface showed the same general pattern of microvilli studding all exposed surfaces out to the cell margin. which were long (with variable height), slight tortuous slender and possessed a micro villus shaft with a very prominent knob.

Keywords: buffalo, cornea, eye, fetus, ontogeny, scanning electron microscopy

Procedia PDF Downloads 127