Search results for: waste organic solid substances
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Search results for: waste organic solid substances

199 Born in Limbo, Living in Limbo and Probably Will Die in Limbo

Authors: Betty Chiyangwa

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The subject of second-generation migrant youth is under-researched in the context of South Africa. Thus, their opinions and views have been marginalised in social science research. This paper addresses this gap by exploring the complexities of second-generation Mozambican migrant youth’s lived experiences in how they construct their identities and develop a sense of belonging in post-apartheid South Africa, specifically in Bushbuckridge. Bushbuckridge was among the earliest districts to accommodate Mozambican refugees to South Africa in the 1970s and remains associated with large numbers of Mozambicans. Drawing on Crenshaw’s (1989) intersectionality approach, the study contributes to knowledge on South-to-South migration by demonstrating how this approach is operationalised to understand the complex lived experiences of a disadvantaged group in life and possibly in death. In conceptualising the notion of identity among second-generation migrant youth, this paper explores the history and present of first and second-generation Mozambican migrants in South Africa to reveal how being born to migrant parents and raised in a hosting country poses life-long complications in one’s identity and sense of belonging. In the quest to form their identities and construct a sense of belonging, migrant youth employ precariously means to navigate the terrane. This is a case study informed by semi-structured interviews and narrative data gathered from 22 second-generation Mozambican migrant youth between 18 and 34 years who were born to at least one Mozambican parent living in Bushbuckridge and raised in South Africa. Views of two key informants from the South African Department of Home Affairs and the local tribal authority provided additional perspectives on second-generation migrant youth’s lived experiences in Bushbuckridge, which were explored thematically and narratively through Braun and Clarke’s (2012) six-step framework for analysing qualitative data. In exploring the interdependency and interconnectedness of social categories and social systems in Bushbuckridge, the findings revealed that participants’ experiences of identity formation and development of a sense of belonging were marginalised in complex, intersectional and precarious ways where they constantly (re)negotiated their daily experiences, which were largely shaped by their paradoxical migrant status in a host country. This study found that, in the quest for belonging, migrant youths were not a perfectly integrated category but evolved from almost daily lived experiences of creating a living that gave them an identity and a sense of belonging in South Africa. The majority of them shared feelings of living in limbo since childhood and fear of possibly dying in limbo with no clear (solid) sense of belonging to either South Africa or Mozambique. This study concludes that there is a strong association between feelings of identity, sense of belonging and levels of social integration. It recommends the development and adoption of a multilayer comprehensive model for understanding second-generation migrant youth identity and belonging in South Africa which encourages a collaborative effort among individual migrant youth, their family members, neighbours, society, and regional and national institutional structures for migrants to enhance and harness their capabilities and improve their wellbeing in South Africa.

Keywords: bushbuckridge, limbo, mozambican migrants, second-generation

Procedia PDF Downloads 70
198 The Display of Environmental Information to Promote Energy Saving Practices: Evidence from a Massive Behavioral Platform

Authors: T. Lazzarini, M. Imbiki, P. E. Sutter, G. Borragan

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While several strategies, such as the development of more efficient appliances, the financing of insulation programs or the rolling out of smart meters represent promising tools to reduce future energy consumption, their implementation relies on people’s decisions-actions. Likewise, engaging with consumers to reshape their behavior has shown to be another important way to reduce energy usage. For these reasons, integrating the human factor in the energy transition has become a major objective for researchers and policymakers. Digital education programs based on tangible and gamified user interfaces have become a new tool with potential effects to reduce energy consumption4. The B2020 program, developed by the firm “Économie d’Énergie SAS”, proposes a digital platform to encourage pro-environmental behavior change among employees and citizens. The platform integrates 160 eco-behaviors to help saving energy and water and reducing waste and CO2 emissions. A total of 13,146 citizens have used the tool so far to declare the range of eco-behaviors they adopt in their daily lives. The present work seeks to build on this database to identify the potential impact of adopted energy-saving behaviors (n=62) to reduce the use of energy in buildings. To this end, behaviors were classified into three categories regarding the nature of its implementation (Eco-habits: e.g., turning-off the light, Eco-actions: e.g., installing low carbon technology such as led light-bulbs and Home-Refurbishments: e.g., such as wall-insulation or double-glazed energy efficient windows). General Linear Models (GLM) disclosed the existence of a significantly higher frequency of Eco-habits when compared to the number of home-refurbishments realized by the platform users. While this might be explained in part by the high financial costs that are associated with home renovation works, it also contrasts with the up to three times larger energy-savings that can be accomplished by these means. Furthermore, multiple regression models failed to disclose the expected relationship between energy-savings and frequency of adopted eco behaviors, suggesting that energy-related practices are not necessarily driven by the correspondent energy-savings. Finally, our results also suggested that people adopting more Eco-habits and Eco-actions were more likely to engage in Home-Refurbishments. Altogether, these results fit well with a growing body of scientific research, showing that energy-related practices do not necessarily maximize utility, as postulated by traditional economic models, and suggest that other variables might be triggering them. Promoting home refurbishments could benefit from the adoption of complementary energy-saving habits and actions.

Keywords: energy-saving behavior, human performance, behavioral change, energy efficiency

Procedia PDF Downloads 200
197 Immobilization of Superoxide Dismutase Enzyme on Layered Double Hydroxide Nanoparticles

Authors: Istvan Szilagyi, Marko Pavlovic, Paul Rouster

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Antioxidant enzymes are the most efficient defense systems against reactive oxygen species, which cause severe damage in living organisms and industrial products. However, their supplementation is problematic due to their high sensitivity to the environmental conditions. Immobilization on carrier nanoparticles is a promising research direction towards the improvement of their functional and colloidal stability. In that way, their applications in biomedical treatments and manufacturing processes in the food, textile and cosmetic industry can be extended. The main goal of the present research was to prepare and formulate antioxidant bionanocomposites composed of superoxide dismutase (SOD) enzyme, anionic clay (layered double hydroxide, LDH) nanoparticle and heparin (HEP) polyelectrolyte. To characterize the structure and the colloidal stability of the obtained compounds in suspension and solid state, electrophoresis, dynamic light scattering, transmission electron microscopy, spectrophotometry, thermogravimetry, X-ray diffraction, infrared and fluorescence spectroscopy were used as experimental techniques. LDH-SOD composite was synthesized by enzyme immobilization on the clay particles via electrostatic and hydrophobic interactions, which resulted in a strong adsorption of the SOD on the LDH surface, i.e., no enzyme leakage was observed once the material was suspended in aqueous solutions. However, the LDH-SOD showed only limited resistance against salt-induced aggregation and large irregularly shaped clusters formed during short term interval even at lower ionic strengths. Since sufficiently high colloidal stability is a key requirement in most of the applications mentioned above, the nanocomposite was coated with HEP polyelectrolyte to develop highly stable suspensions of primary LDH-SOD-HEP particles. HEP is a natural anticoagulant with one of the highest negative line charge density among the known macromolecules. The experimental results indicated that it strongly adsorbed on the oppositely charged LDH-SOD surface leading to charge inversion and to the formation of negatively charged LDH-SOD-HEP. The obtained hybrid materials formed stable suspension even under extreme conditions, where classical colloid chemistry theories predict rapid aggregation of the particles and unstable suspensions. Such a stabilization effect originated from electrostatic repulsion between the particles of the same sign of charge as well as from steric repulsion due to the osmotic pressure raised during the overlap of the polyelectrolyte chains adsorbed on the surface. In addition, the SOD enzyme kept its structural and functional integrity during the immobilization and coating processes and hence, the LDH-SOD-HEP bionanocomposite possessed excellent activity in decomposition of superoxide radical anions, as revealed in biochemical test reactions. In conclusion, due to the improved colloidal stability and the good efficiency in scavenging superoxide radical ions, the developed enzymatic system is a promising antioxidant candidate for biomedical or other manufacturing processes, wherever the aim is to decompose reactive oxygen species in suspensions.

Keywords: clay, enzyme, polyelectrolyte, formulation

Procedia PDF Downloads 268
196 Deep Learning in Chest Computed Tomography to Differentiate COVID-19 from Influenza

Authors: Hongmei Wang, Ziyun Xiang, Ying liu, Li Yu, Dongsheng Yue

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Intro: The COVID-19 (Corona Virus Disease 2019) has greatly changed the global economic, political and financial ecology. The mutation of the coronavirus in the UK in December 2020 has brought new panic to the world. Deep learning was performed on Chest Computed tomography (CT) of COVID-19 and Influenza and describes their characteristics. The predominant features of COVID-19 pneumonia was ground-glass opacification, followed by consolidation. Lesion density: most lesions appear as ground-glass shadows, and some lesions coexist with solid lesions. Lesion distribution: the focus is mainly on the dorsal side of the periphery of the lung, with the lower lobe of the lungs as the focus, and it is often close to the pleura. Other features it has are grid-like shadows in ground glass lesions, thickening signs of diseased vessels, air bronchi signs and halo signs. The severe disease involves whole bilateral lungs, showing white lung signs, air bronchograms can be seen, and there can be a small amount of pleural effusion in the bilateral chest cavity. At the same time, this year's flu season could be near its peak after surging throughout the United States for months. Chest CT for Influenza infection is characterized by focal ground glass shadows in the lungs, with or without patchy consolidation, and bronchiole air bronchograms are visible in the concentration. There are patchy ground-glass shadows, consolidation, air bronchus signs, mosaic lung perfusion, etc. The lesions are mostly fused, which is prominent near the hilar and two lungs. Grid-like shadows and small patchy ground-glass shadows are visible. Deep neural networks have great potential in image analysis and diagnosis that traditional machine learning algorithms do not. Method: Aiming at the two major infectious diseases COVID-19 and influenza, which are currently circulating in the world, the chest CT of patients with two infectious diseases is classified and diagnosed using deep learning algorithms. The residual network is proposed to solve the problem of network degradation when there are too many hidden layers in a deep neural network (DNN). The proposed deep residual system (ResNet) is a milestone in the history of the Convolutional neural network (CNN) images, which solves the problem of difficult training of deep CNN models. Many visual tasks can get excellent results through fine-tuning ResNet. The pre-trained convolutional neural network ResNet is introduced as a feature extractor, eliminating the need to design complex models and time-consuming training. Fastai is based on Pytorch, packaging best practices for in-depth learning strategies, and finding the best way to handle diagnoses issues. Based on the one-cycle approach of the Fastai algorithm, the classification diagnosis of lung CT for two infectious diseases is realized, and a higher recognition rate is obtained. Results: A deep learning model was developed to efficiently identify the differences between COVID-19 and influenza using chest CT.

Keywords: COVID-19, Fastai, influenza, transfer network

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195 Rendering Religious References in English: Naguib Mahfouz in the Arabic as a Foreign Language Classroom

Authors: Shereen Yehia El Ezabi

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The transition from the advanced to the superior level of Arabic proficiency is widely known to pose considerable challenges for English speaking students of Arabic as a Foreign Language (AFL). Apart from the increasing complexity of the grammar at this juncture, together with the sprawling vocabulary, to name but two of those challenges, there is also the somewhat less studied hurdle along the way to superior level proficiency, namely, the seeming opacity of many aspects of Arab/ic culture to such learners. This presentation tackles one specific dimension of such issues: religious references in literary texts. It illustrates how carefully constructed translation activities may be used to expand and deepen students’ understanding and use of them. This is shown to be vital for making the leap to the desired competency, given that such elements, as reflected in customs, traditions, institutions, worldviews, and formulaic expressions lie at the very core of Arabic culture and, as such, pervade all modes and levels of Arabic discourse. A short story from the collection “Stories from Our Alley”, by preeminent novelist Naguib Mahfouz is selected for use in this context, being particularly replete with such religious references, of which religious expressions will form the focus of the presentation. As a miniature literary work, it provides an organic whole, so to speak, within which to explore with the class the most precise denotation, as well as the subtlest connotation of each expression in an effort to reach the ‘best’ English rendering. The term ‘best’ refers to approximating the meaning in its full complexity from the source text, in this case Arabic, to the target text, English, according to the concept of equivalence in translation theory. The presentation will show how such a process generates the sort of thorough discussion and close text analysis which allows students to gain valuable insight into this central idiom of Arabic. A variety of translation methods will be highlighted, gleaned from the presenter’s extensive work with advanced/superior students in the Center for Arabic Study Abroad (CASA) program at the American University in Cairo. These begin with the literal rendering of expressions, with the purpose of reinforcing vocabulary learning and practicing the rules of derivational morphology as they form each word, since the larger context remains that of an AFL class, as opposed to a translation skills program. However, departures from the literal approach are subsequently explored by degrees, moving along the spectrum of functional and pragmatic freer translations in order to transmit the ‘real’ meaning in readable English to the target audience- no matter how culture/religion specific the expression- while remaining faithful to the original. Samples from students’ work pre and post discussion will be shared, demonstrating how class consensus is formed as to the final English rendering, proposed as the closest match to the Arabic, and shown to be the result of the above activities. Finally, a few examples of translation work which students have gone on to publish will be shared to corroborate the effectiveness of this teaching practice.

Keywords: superior level proficiency in Arabic as a foreign language, teaching Arabic as a foreign language, teaching idiomatic expressions, translation in foreign language teaching

Procedia PDF Downloads 198
194 Gas Systems of the Amadeus Basin, Australia

Authors: Chris J. Boreham, Dianne S. Edwards, Amber Jarrett, Justin Davies, Robert Poreda, Alex Sessions, John Eiler

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The origins of natural gases in the Amadeus Basin have been assessed using molecular and stable isotope (C, H, N, He) systematics. A dominant end-member thermogenic, oil-associated gas is considered for the Ordovician Pacoota−Stairway sandstones of the Mereenie gas and oil field. In addition, an abiogenic end-member is identified in the latest Proterozoic lower Arumbera Sandstone of the Dingo gasfield, being most likely associated with radiolysis of methane with polymerisation to wet gases. The latter source assignment is based on a similar geochemical fingerprint derived from the laboratory gamma irradiation experiments on methane. A mixed gas source is considered for the Palm Valley gasfield in the Ordovician Pacoota Sandstone. Gas wetness (%∑C₂−C₅/∑C₁−C₅) decreases in the order Mereenie (19.1%) > Palm Valley (9.4%) > Dingo (4.1%). Non-produced gases at Magee-1 (23.5%; Late Proterozoic Heavitree Quartzite) and Mount Kitty-1 (18.9%; Paleo-Mesoproterozoic fractured granitoid basement) are very wet. Methane thermometry based on clumped isotopes of methane (¹³CDH₃) is consistent with the abiogenic origin for the Dingo gas field with methane formation temperature of 254ᵒC. However, the low methane formation temperature of 57°C for the Mereenie gas suggests either a mixed thermogenic-biogenic methane source or there is no thermodynamic equilibrium between the methane isotopomers. The shallow reservoir depth and present-day formation temperature below 80ᵒC would support microbial methanogenesis, but there is no accompanying alteration of the C- and H-isotopes of the wet gases and CO₂ that is typically associated with biodegradation. The Amadeus Basin gases show low to extremely high inorganic gas contents. Carbon dioxide is low in abundance (< 1% CO₂) and becomes increasing depleted in ¹³C from the Palm Valley (av. δ¹³C 0‰) to the Mereenie (av. δ¹³C -6.6‰) and Dingo (av. δ¹³C -14.3‰) gas fields. Although the wide range in carbon isotopes for CO₂ is consistent with multiple origins from inorganic to organic inputs, the most likely process is fluid-rock alteration with enrichment in ¹²C in the residual gaseous CO₂ accompanying progressive carbonate precipitation within the reservoir. Nitrogen ranges from low−moderate (1.7−9.9% N₂) abundance (Palm Valley av. 1.8%; Mereenie av. 9.1%; Dingo av. 9.4%) to extremely high abundance in Magee-1 (43.6%) and Mount Kitty-1 (61.0%). The nitrogen isotopes for the production gases have δ¹⁵N = -3.0‰ for Mereenie, -3.0‰ for Palm Valley and -7.1‰ for Dingo, suggest all being mixed inorganic and thermogenic nitrogen sources. Helium (He) abundance varies over a wide range from a low of 0.17% to one of the world’s highest at 9% (Mereenie av. 0.23%; Palm Valley av. 0.48%, Dingo av. 0.18%, Magee-1 6.2%; Mount Kitty-1 9.0%). Complementary helium isotopes (R/Ra = ³He/⁴Hesample / ³He/⁴Heair) range from 0.013 to 0.031 R/Ra, indicating a dominant crustal origin for helium with a sustained input of radiogenic 4He from the decomposition of U- and Th-bearing minerals, effectively diluting any original mantle helium input. The high helium content in the non-produced gases compared to the shallower producing wells most likely reflects their stratigraphic position relative to the Tonian Bitter Springs Group with the former below and the latter above an effective carbonate-salt seal.

Keywords: amadeus gas, thermogenic, abiogenic, C, H, N, He isotopes

Procedia PDF Downloads 195
193 Blue Hydrogen Production Via Catalytic Aquathermolysis Coupled with Direct Carbon Dioxide Capture Via Adsorption

Authors: Sherif Fakher

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Hydrogen has been gaining a lot of global attention as an uprising contributor in the energy sector. Labeled as an energy carrier, hydrogen is used in many industries and can be used to generate electricity via fuel cells. Blue hydrogen involves the production of hydrogen from hydrocarbons using different processes that emit CO₂. However, the CO₂ is captured and stored. Hence, very little environmental damage occurs during the hydrogen production process. This research investigates the ability to use different catalysts for the production of hydrogen from different hydrocarbon sources, including coal, oil, and gas, using a two-step Aquathermolysis reaction. The research presents the results of experiments conducted to evaluate different catalysts and also highlights the main advantages of this process over other blue hydrogen production methods, including methane steam reforming, autothermal reforming, and oxidation. Two methods of hydrogen generation were investigated including partial oxidation and aquathermolysis. For those two reactions, the reaction kinetics, thermodynamics, and medium were all investigated. Following this, experiments were conducted to test the hydrogen generation potential from both methods. The porous media tested were sandstone, ash, and prozzolanic material. The spent oils used were spent motor oil and spent vegetable oil from cooking. Experiments were conducted at temperatures up to 250 C and pressures up to 3000 psi. Based on the experimental results, mathematical models were developed to predict the hydrogen generation potential at higher thermodynamic conditions. Since both partial oxidation and aquathermolysis require relatively high temperatures to undergo, it was important to devise a method by which these high temperatures can be generated at a low cost. This was done by investigating two factors, including the porous media used and the reliance on the spent oil. Of all the porous media used, the ash had the highest thermal conductivity. The second step was the partial combustion of part of the spent oil to generate the heat needed to reach the high temperatures. This reduced the cost of the heat generation significantly. For the partial oxidation reaction, the spent oil was burned in the presence of a limited oxygen concentration to generate carbon monoxide. The main drawback of this process was the need for burning. This resulted in the generation of other harmful and environmentally damaging gases. Aquathermolysis does not rely on burning, which makes it the cleaner alternative. However, it needs much higher temperatures to run the reaction. When comparing the hydrogen generation potential for both using gas chromatography, aquathermolysis generated 23% more hydrogen using the same volume of spent oil compared to partial oxidation. This research introduces the concept of using spent oil for hydrogen production. This can be a very promising method to produce a clean source of energy using a waste product. This can also help reduce the reliance on freshwater for hydrogen generation which can divert the usage of freshwater to other more important applications.

Keywords: blue hydrogen production, catalytic aquathermolysis, direct carbon dioxide capture, CCUS

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192 Numerical Investigation on Design Method of Timber Structures Exposed to Parametric Fire

Authors: Robert Pečenko, Karin Tomažič, Igor Planinc, Sabina Huč, Tomaž Hozjan

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Timber is favourable structural material due to high strength to weight ratio, recycling possibilities, and green credentials. Despite being flammable material, it has relatively high fire resistance. Everyday engineering practice around the word is based on an outdated design of timber structures considering standard fire exposure, while modern principles of performance-based design enable use of advanced non-standard fire curves. In Europe, standard for fire design of timber structures EN 1995-1-2 (Eurocode 5) gives two methods, reduced material properties method and reduced cross-section method. In the latter, fire resistance of structural elements depends on the effective cross-section that is a residual cross-section of uncharred timber reduced additionally by so called zero strength layer. In case of standard fire exposure, Eurocode 5 gives a fixed value of zero strength layer, i.e. 7 mm, while for non-standard parametric fires no additional comments or recommendations for zero strength layer are given. Thus designers often implement adopted 7 mm rule also for parametric fire exposure. Since the latest scientific evidence suggests that proposed value of zero strength layer can be on unsafe side for standard fire exposure, its use in the case of a parametric fire is also highly questionable and more numerical and experimental research in this field is needed. Therefore, the purpose of the presented study is to use advanced calculation methods to investigate the thickness of zero strength layer and parametric charring rates used in effective cross-section method in case of parametric fire. Parametric studies are carried out on a simple solid timber beam that is exposed to a larger number of parametric fire curves Zero strength layer and charring rates are determined based on the numerical simulations which are performed by the recently developed advanced two step computational model. The first step comprises of hygro-thermal model which predicts the temperature, moisture and char depth development and takes into account different initial moisture states of timber. In the second step, the response of timber beam simultaneously exposed to mechanical and fire load is determined. The mechanical model is based on the Reissner’s kinematically exact beam model and accounts for the membrane, shear and flexural deformations of the beam. Further on, material non-linear and temperature dependent behaviour is considered. In the two step model, the char front temperature is, according to Eurocode 5, assumed to have a fixed temperature of around 300°C. Based on performed study and observations, improved levels of charring rates and new thickness of zero strength layer in case of parametric fires are determined. Thus, the reduced cross section method is substantially improved to offer practical recommendations for designing fire resistance of timber structures. Furthermore, correlations between zero strength layer thickness and key input parameters of the parametric fire curve (for instance, opening factor, fire load, etc.) are given, representing a guideline for a more detailed numerical and also experimental research in the future.

Keywords: advanced numerical modelling, parametric fire exposure, timber structures, zero strength layer

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191 Use of Low-Cost Hydrated Hydrogen Sulphate-Based Protic Ionic Liquids for Extraction of Cellulose-Rich Materials from Common Wheat (Triticum Aestivum) Straw

Authors: Chris Miskelly, Eoin Cunningham, Beatrice Smyth, John. D. Holbrey, Gosia Swadzba-Kwasny, Emily L. Byrne, Yoan Delavoux, Mantian Li.

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Recently, the use of ionic liquids (ILs) for the preparation of lignocellulose derived cellulosic materials as alternatives to petrochemical feedstocks has been the focus of considerable research interest. While the technical viability of IL-based lignocellulose treatment methodologies has been well established, the high cost of reagents inhibits commercial feasibility. This work aimed to assess the technoeconomic viability of the preparation of cellulose rich materials (CRMs) using protic ionic liquids (PILs) synthesized from low cost alkylamines and sulphuric acid. For this purpose, the tertiary alkylamines, triethylamine, and dimethylbutylamine were selected. Bulk scale production cost of the synthesized PILs, triethylammonium hydrogen sulphate and dimetheylbutylammonium hydrogen sulphate, was reported as $0.78 kg-1 to $1.24 kg-1. CRMs were prepared through the treatment of common wheat (Triticum aestivum) straw with these PILs. By controlling treatment parameters, CRMs with a cellulose content of ≥ 80 wt% were prepared. This was achieved using a T. aestivum straw to PIL loading ratio of 1:15 w/w, a treatment duration of 180 minutes, and ethanol as a cellulose antisolvent. Infrared spectra data and decreased onset degradation temperature of CRMs (ΔTONSET ~ 70 °C) suggested the formation of cellulose sulphate esters during treatment. Chemical derivatisation can aid the dispersion of prepared CRMs in non-polar polymer/ composite matrices, but act as a barrier to thermal processing at temperatures above 150 °C. It was also shown that treatment increased the crystallinity of CRMs (ΔCrI ~ 40 %) without altering the native crystalline structure or crystallite size (~ 2.6 nm) of cellulose; peaks associated with the cellulose I crystalline planes (110), (200), and (004) were observed at Bragg angles 16.0 °, 22.5 ° and 35.0 ° respectively. This highlighted the inability of assessed PILs to dissolve crystalline cellulose and was attributed to the high acidity (pKa ~ - 1.92 to - 6.42) of sulphuric acid derived anions. Electron micrographs revealed that the stratified multilayer tissue structure of untreated T. aestivum straw was significantly modified during treatment. T. aestivum straw particles were disassembled during treatment, with prepared CRMs adopting a golden-brown film-like appearance. This work demonstrated the degradation of non-cellulosic fractions of lignocellulose without dissolution of cellulose. It is the first to report on the derivatisation of cellulose during treatment with protic hydrogen sulphate ionic liquids, and the potential implications of this with reference to biopolymer feedstock preparation.

Keywords: cellulose, extraction, protic ionic liquids, esterification, thermal stability, waste valorisation, biopolymer feedstock

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190 Modeling of Hot Casting Technology of Beryllium Oxide Ceramics with Ultrasonic Activation

Authors: Zamira Sattinova, Tassybek Bekenov

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The article is devoted to modeling the technology of hot casting of beryllium oxide ceramics. The stages of ultrasonic activation of beryllium oxide slurry in the plant vessel to improve the rheological property, hot casting in the moulding cavity with cooling and solidification of the casting are described. Thermoplastic slurry (hereinafter referred to as slurry) shows the rheology of a non-Newtonian fluid with yield and plastic viscosity. Cooling-solidification of the slurry in the forming cavity occurs in the liquid, taking into account crystallization and solid state. In this work is the method of calculation of hot casting of the slurry using the method of effective molecular viscosity of viscoplastic fluid. It is shown that the slurry near the cooled wall is in a state of crystallization and plasticity, and the rest may still be in the liquid phase. Nonuniform distribution of temperature, density and concentration of kinetically free binder takes place along the cavity section. This leads to compensation of shrinkage by the influx of slurry from the liquid into the crystallization zones and plasticity of the castings. In the plasticity zone, the shrinkage determined by the concentration of kinetically free binder is compensated under the action of the pressure gradient. The solidification mechanism, as well as the mechanical behavior of the casting mass during casting, the rheological and thermophysical properties of the thermoplastic BeO slurry due to ultrasound exposure have not been well studied. Nevertheless, experimental data allow us to conclude that the effect of ultrasonic vibrations on the slurry mass leads to it: a change in structure, an increase in technological properties, a decrease in heterogeneity and a change in rheological properties. In the course of experiments, the effect of ultrasonic treatment and its duration on the change in viscosity and ultimate shear stress of the slurry depending on temperature (55-75℃) and the mass fraction of the binder (10 - 11.7%) have been studied. At the same time, changes in these properties before and after ultrasound exposure have been analyzed, as well as the nature of the flow in the system under study. The experience of operating the unit with ultrasonic impact has shown that at the same time, the casting capacity of the slurry increases by an average of 15%, and the viscosity decreases by more than half. Experimental study of physicochemical properties and phase change with simultaneous consideration of all factors affecting the quality of products in the process of continuous casting is labor-intensive. Therefore, an effective way to control the physical processes occurring in the formation of articles with predetermined properties and shapes is to simulate the process and determine its basic characteristics. The results of the calculations show the whole stage of hot casting of beryllium oxide slurry, taking into account the change in its state of aggregation. Ultrasonic treatment improves rheological properties and increases the fluidity of the slurry in the forming cavity. Calculations show the influence of velocity, temperature factors and structural data of the cavity on the cooling-solidification process of the casting. In the calculations, conditions for molding with shrinkage of the slurry by hot casting have been found, which makes it possible to obtain a solidifying product with a uniform beryllium oxide structure at the outlet of the cavity.

Keywords: hot casting, thermoplastic slurry molding, shrinkage, beryllium oxide

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189 Soil Wind Erosion, Nutrients, and Crop Yield Response to Conservation Tillage in North China: A Field Study in a Semi-Arid and Wind Erosion Region after 9 Years

Authors: Fahui Jiang, Xinwei Xue, Liyan Zhang, Yanyan Zuo, Hao Zhang, Wei Zheng, Limei Bian, Lingling Hu, Chunlei Hao, Jianghong Du, Yanhua Ci, Ruibao Cheng, Ciren Dawa, Mithun Biswas, Mahbub Ul Islam, Fansheng Meng, Xinhua Peng

Abstract:

Context: Soil erosion is a global issue that poses a significant threat to agricultural sustainability, particular in northern of China, which experiences the most severe wind erosion worldwide. Conservation tillage is vital in arid regions for preserving soil, enhancing water retention, and sustaining agricultural productivity in the face of limited rainfall. However, the long-term impacts of conservation tillage in semi-arid regions, especially its effects on soil health, wind erosion, and crop productivity, are poorly understood. Objective: Assess the impacts of conservation tillage on soil hydrothermal properties, wind erosion rates, nutrient dynamics, and crop yield, as well as elucidating the underlying mechanisms driving these impacts. Methods: A 9-year in-situ study was conducted in Chifeng, Inner Mongolia Province, comparing conventional rotary tillage (CK) with two conservation tillage methods: no-tillage with straw mulching (CT-1) and no-tillage with standing straw (CT-2). Results: Soil bulk density increased significantly under CT-1 and CT-2 in the topsoil layer (0–20 cm) compared with CK. Soil moisture content exhibited a significant increase pattern under CT-1 and CT-2, while soil temperature decreased under CT-1 but increased under CT-2, relative to CK. These variations in soil hydrothermal properties were more pronounced during the early (critical) crop growth stages and higher temperature conditions (afternoon). Soil loss due to wind erosion, accumulated from a height of 0–50 cm on the land surface, was reduced by 31.3 % and 25.5 % under CT-1 and by 51.5 % and 38.2 % under CT-2 in 2021 and 2022, respectively, compared to CK. Furthermore, the proportion of soil finer particles (clay and silt) increased under CT due to reduced wind erosion. Soil organic carbon significantly increased throughout the soil profile (0–60 cm), particularly in the deeper layers (20–40 cm and 40–60 cm), compared to the surface layer (0–20 cm), with corresponding increases of +57.0 % and +0.18 %, +66.2 % and +80.3 %, and +27.1 % and +14.2 % under CT-1 and CT-2, respectively, relative to CK in 2021. The concentrations of soil nutrients such as total nitrogen, available nitrogen, and available phosphorus and potassium, consistently increased under CT-1 and CT-2 compared to CK, with notable enhancements observed in the topsoil layer (0–20 cm) before seedling time, albeit declining after crop harvest. Generally, CT treatments significantly increased dry matter accumulation (+4.8 % to +30.8 %) and grain yield (+2.22 % to +0.44 %) of maize compared to CK in the semi-arid region over the 9-year study period, particularly notable in dry years and with long-term application. Conclusions and implications: Conservation tillage in semi-arid regions enhanced soil properties, reduced soil erosion, and increased soil nutrient dynamics and crop yield, promising sustainable agricultural practices with environmental benefits. Furthermore, our findings suggest that no-tillage with straw mulching is more suitable for dry and wind erosion sensitive regions.

Keywords: no tillage, conventional tillage, soil water, soil temperature, soil physics

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188 Surviral: An Agent-Based Simulation Framework for Sars-Cov-2 Outcome Prediction

Authors: Sabrina Neururer, Marco Schweitzer, Werner Hackl, Bernhard Tilg, Patrick Raudaschl, Andreas Huber, Bernhard Pfeifer

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History and the current outbreak of Covid-19 have shown the deadly potential of infectious diseases. However, infectious diseases also have a serious impact on areas other than health and healthcare, such as the economy or social life. These areas are strongly codependent. Therefore, disease control measures, such as social distancing, quarantines, curfews, or lockdowns, have to be adopted in a very considerate manner. Infectious disease modeling can support policy and decision-makers with adequate information regarding the dynamics of the pandemic and therefore assist in planning and enforcing appropriate measures that will prevent the healthcare system from collapsing. In this work, an agent-based simulation package named “survival” for simulating infectious diseases is presented. A special focus is put on SARS-Cov-2. The presented simulation package was used in Austria to model the SARS-Cov-2 outbreak from the beginning of 2020. Agent-based modeling is a relatively recent modeling approach. Since our world is getting more and more complex, the complexity of the underlying systems is also increasing. The development of tools and frameworks and increasing computational power advance the application of agent-based models. For parametrizing the presented model, different data sources, such as known infections, wastewater virus load, blood donor antibodies, circulating virus variants and the used capacity for hospitalization, as well as the availability of medical materials like ventilators, were integrated with a database system and used. The simulation result of the model was used for predicting the dynamics and the possible outcomes and was used by the health authorities to decide on the measures to be taken in order to control the pandemic situation. The survival package was implemented in the programming language Java and the analytics were performed with R Studio. During the first run in March 2020, the simulation showed that without measures other than individual personal behavior and appropriate medication, the death toll would have been about 27 million people worldwide within the first year. The model predicted the hospitalization rates (standard and intensive care) for Tyrol and South Tyrol with an accuracy of about 1.5% average error. They were calculated to provide 10-days forecasts. The state government and the hospitals were provided with the 10-days models to support their decision-making. This ensured that standard care was maintained for as long as possible without restrictions. Furthermore, various measures were estimated and thereafter enforced. Among other things, communities were quarantined based on the calculations while, in accordance with the calculations, the curfews for the entire population were reduced. With this framework, which is used in the national crisis team of the Austrian province of Tyrol, a very accurate model could be created on the federal state level as well as on the district and municipal level, which was able to provide decision-makers with a solid information basis. This framework can be transferred to various infectious diseases and thus can be used as a basis for future monitoring.

Keywords: modelling, simulation, agent-based, SARS-Cov-2, COVID-19

Procedia PDF Downloads 174
187 Computer Aided Design Solution Based on Genetic Algorithms for FMEA and Control Plan in Automotive Industry

Authors: Nadia Belu, Laurenţiu Mihai Ionescu, Agnieszka Misztal

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The automotive industry is one of the most important industries in the world that concerns not only the economy, but also the world culture. In the present financial and economic context, this field faces new challenges posed by the current crisis, companies must maintain product quality, deliver on time and at a competitive price in order to achieve customer satisfaction. Two of the most recommended techniques of quality management by specific standards of the automotive industry, in the product development, are Failure Mode and Effects Analysis (FMEA) and Control Plan. FMEA is a methodology for risk management and quality improvement aimed at identifying potential causes of failure of products and processes, their quantification by risk assessment, ranking of the problems identified according to their importance, to the determination and implementation of corrective actions related. The companies use Control Plans realized using the results from FMEA to evaluate a process or product for strengths and weaknesses and to prevent problems before they occur. The Control Plans represent written descriptions of the systems used to control and minimize product and process variation. In addition Control Plans specify the process monitoring and control methods (for example Special Controls) used to control Special Characteristics. In this paper we propose a computer-aided solution with Genetic Algorithms in order to reduce the drafting of reports: FMEA analysis and Control Plan required in the manufacture of the product launch and improved knowledge development teams for future projects. The solution allows to the design team to introduce data entry required to FMEA. The actual analysis is performed using Genetic Algorithms to find optimum between RPN risk factor and cost of production. A feature of Genetic Algorithms is that they are used as a means of finding solutions for multi criteria optimization problems. In our case, along with three specific FMEA risk factors is considered and reduce production cost. Analysis tool will generate final reports for all FMEA processes. The data obtained in FMEA reports are automatically integrated with other entered parameters in Control Plan. Implementation of the solution is in the form of an application running in an intranet on two servers: one containing analysis and plan generation engine and the other containing the database where the initial parameters and results are stored. The results can then be used as starting solutions in the synthesis of other projects. The solution was applied to welding processes, laser cutting and bending to manufacture chassis for buses. Advantages of the solution are efficient elaboration of documents in the current project by automatically generating reports FMEA and Control Plan using multiple criteria optimization of production and build a solid knowledge base for future projects. The solution which we propose is a cheap alternative to other solutions on the market using Open Source tools in implementation.

Keywords: automotive industry, FMEA, control plan, automotive technology

Procedia PDF Downloads 406
186 The Misuse of Free Cash and Earnings Management: An Analysis of the Extent to Which Board Tenure Mitigates Earnings Management

Authors: Michael McCann

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Managerial theories propose that, in joint stock companies, executives may be tempted to waste excess free cash on unprofitable projects to keep control of resources. In order to conceal their projects' poor performance, they may seek to engage in earnings management. On the one hand, managers may manipulate earnings upwards in order to post ‘good’ performances and safeguard their position. On the other, since managers pursuit of unrewarding investments are likely to lead to low long-term profitability, managers will use negative accruals to reduce current year’s earnings, smoothing earnings over time in order to conceal the negative effects. Agency models argue that boards of directors are delegated by shareholders to ensure that companies are governed properly. Part of that responsibility is ensuring the reliability of financial information. Analyses of the impact of board characteristics, particularly board independence on the misuse of free cash flow and earnings management finds conflicting evidence. However, existing characterizations of board independence do not account for such directors gaining firm-specific knowledge over time, influencing their monitoring ability. Further, there is little analysis of the influence of the relative experience of independent directors and executives on decisions surrounding the use of free cash. This paper contributes to this literature regarding the heterogeneous characteristics of boards by investigating the influence of independent director tenure on earnings management and the relative tenures of independent directors and Chief Executives. A balanced panel dataset comprising 51 companies across 11 annual periods from 2005 to 2015 is used for the analysis. In each annual period, firms were classified as conducting earnings management if they had discretionary accruals in the bottom quartile (downwards) and top quartile (upwards) of the distributed values for the sample. Logistical regressions were conducted to determine the marginal impact of independent board tenure and a number of control variables on the probability of conducting earnings management. The findings indicate that both absolute and relative measures of board independence and experience do not have a significant impact on the likelihood of earnings management. It is the level of free cash flow which is the major influence on the probability of earnings management. Higher free cash flow increases the probability of earnings management significantly. The research also investigates whether board monitoring of earnings management is contingent on the level of free cash flow. However, the results suggest that board monitoring is not amplified when free cash flow is higher. This suggests that the extent of earnings management in companies is determined by a range of company, industry and situation-specific factors.

Keywords: corporate governance, boards of directors, agency theory, earnings management

Procedia PDF Downloads 233
185 Valorization of Underutilized Fish Species Through a Multidisciplinary Approach

Authors: Tiziana Pepe, Gerardo Manfreda, Adriana Ianieri, Aniello Anastasio

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The sustainable exploitation of marine biological resources is among the most important objectives of the EU's Common Fisheries Policy (CFP). Currently, Europe imports about 65% of its fish products, indicating that domestic production does not meet consumer demand. Despite the availability of numerous commercially significant fish species, European consumption is concentrated on a limited number of products (e.g., sea bass, sea bream, shrimp). Many native species, present in large quantities in the Mediterranean Sea, are little known to consumers and are therefore considered ‘fishing by-products’. All the data presented so far indicate a significant waste of local resources and the overexploitation of a few fish stocks. It is therefore necessary to develop strategies that guide the market towards sustainable conversion. The objective of this work was to valorize underutilized fish species of the Mediterranean Sea through a multidisciplinary approach. To this end, three fish species were sampled: Atlantic Horse Mackerel (Trachurus trachurus), Bogue (Boops boops), and Common Dolphinfish (Coryphaena hippurus). Nutritional properties (water %, fats, proteins, ashes, salts), physical/chemical properties (TVB-N, histamine, pH), and rheological properties (color, texture, viscosity) were analyzed. The analyses were conducted on both fillets and processing by-products. Additionally, mitochondrial DNA (mtDNA) was extracted from the muscle of each species. The mtDNA was then sequenced using the Illumina NGS technique. The analysis of nutritional properties classified the fillets of the sampled species as lean or semi-fat, as they had a fat content of less than 3%, while the by-products showed a higher lipid content (2.7-5%). The protein percentage for all fillets was 22-23%, while for processing by-products, the protein concentration was 18-19% for all species. Rheological analyses showed an increase in viscosity in saline solution in all species, indicating their potential suitability for industrial processing. High-quality and quantity complete mtDNA was extracted from all analyzed species. The complete mitochondrial genome sequences were successfully obtained and annotated. The results of this study suggest that all analyzed species are suitable for both human consumption and feed production. The sequencing of the complete mtDNA and its availability in international databases will be useful for accurate phylogenetic analysis and proper species identification, even in prepared and processed products. Underutilized fish species represent an important economic resource. Encouraging their consumption could limit the phenomenon of overfishing, protecting marine biodiversity. Furthermore, the valorization of these species will increase national fish production, supporting the local economy, cultural, and gastronomic tradition, and optimizing the exploitation of Mediterranean resources in accordance with the CFP.

Keywords: mtDNA, nutritional analysis, sustainable fisheries, underutilized fish species

Procedia PDF Downloads 30
184 Investigation of Resilient Circles in Local Community and Industry: Waju-Traditional Culture in Japan and Modern Technology Application

Authors: R. Ueda

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Today global society is seeking resilient partnership in local organizations and individuals, which realizes multi-stakeholders relationship. Although it is proposed by modern global framework of sustainable development, it is conceivable that such affiliation can be found out in the traditional local community in Japan, and that traditional spirit is tacitly sustaining in modern context of disaster mitigation in society and economy. Then this research is aiming to clarify and analyze implication for the global world by actual case studies. Regional and urban resilience is the ability of multi-stakeholders to cooperate flexibly and to adapt in response to changes in the circumstances caused by disasters, but there are various conflicts affecting coordination of disaster relief measures. These conflicts arise not only from a lack of communication and an insufficient network, but also from the difficulty to jointly draw common context from fragmented information. This is because of the weakness of our modern engineering which focuses on maintenance and restoration of individual systems. Here local ‘circles’ holistically includes local community and interacts periodically. Focusing on examples of resilient organizations and wisdom created in communities, what can be seen throughout history is a virtuous cycle where the information and the knowledge are structured, the context to be adapted becomes clear, and an adaptation at a higher level is made possible, by which the collaboration between organizations is deepened and expanded. And the wisdom of a solid and autonomous disaster prevention formed by the historical community called’ Waju’ – an area surrounded by circle embankment to protect the settlement from flood – lives on in government efforts of the coastal industrial island of today. Industrial company there collaborates to create a circle including common evacuation space, road access improvement and infrastructure recovery. These days, people here adopts new interface technology. Large-scale AR- Augmented Reality for more than hundred people is expressing detailed hazard by tsunami and liquefaction. Common experiences of the major disaster space and circle of mutual discussion are enforcing resilience. Collaboration spirit lies in the center of circle. A consistent key point is a virtuous cycle where the information and the knowledge are structured, the context to be adapted becomes clear, and an adaptation at a higher level is made possible, by which the collaboration between organizations is deepened and expanded. This writer believes that both self-governing human organizations and the societal implementation of technical systems are necessary. Infrastructure should be autonomously instituted by associations of companies and other entities in industrial areas for working closely with local governments. To develop advanced disaster prevention and multi-stakeholder collaboration, partnerships among industry, government, academia and citizens are important.

Keywords: industrial recovery, multi-sakeholders, traditional culture, user experience, Waju

Procedia PDF Downloads 113
183 Growth Mechanism and Sensing Behaviour of Sn Doped ZnO Nanoprisms Prepared by Thermal Evaporation Technique

Authors: Sudip Kumar Sinha, Saptarshi Ghosh

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While there’s a perpetual buzz around zinc oxide (ZnO) superstructures for their unique optical features, the versatile material has been constantly utilized to manifest tailored electronic properties through rendition of distinct morphologies. And yet, the unorthodox approach of implementing the novel 1D nanostructures of ZnO (pristine or doped) for volatile sensing applications has ample scope to accommodate new unconventional morphologies. In the last two decades, solid-state sensors have attracted much curiosity for their relevance in identifying pollutant, toxic and other industrial gases. In particular gas sensors based on metal oxide semiconducting (wide Eg) nanomaterials have recently attracted intensive attention owing to their high sensitivity and fast response and recovery time. These materials when exposed to air, the atmospheric O2 dissociates and get absorb on the surface of the sensors by trapping the outermost shell electrons. Finally a depleted zone on the surface of the sensors is formed, that enhances the potential barrier height at grain boundary . Once a target gas is exposed to the sensor, the chemical interaction between the chemisorbed oxygen and the specific gas liberates the trapped electrons. Therefore altering the amount of adsorbate is a considerable approach to improve the sensitivity of any target gas/vapour molecule. Likewise, this study presents a spontaneous but self catalytic creation of Sn-doped ZnO hexagonal nanoprisms on Si (100) substrates through thermal evaporation-condensation method, and their subsequent deployment for volatile sensing. In particular, the sensors were utilized to detect molecules of ethanol, acetone and ammonia below their permissible exposure limits which returned sensitivities of around 85%, 80% and 50% respectively. The influence of Sn concentration on the growth, microstructural and optical properties of the nanoprisms along with its role in augmenting the sensing parameters has been detailed. The single-crystalline nanostructures have a typical diameter ranging from 300 to 500 nm and a length that extends up to few micrometers. HRTEM images confirmed the hexagonal crystallography for the nanoprisms, while SAED pattern asserted the single crystalline nature. The growth habit is along the low index <0001>directions. It has been seen that the growth mechanism of the as-deposited nanostructures are directly influenced by varying supersaturation ratio, fairly high substrate temperatures, and specified surface defects in certain crystallographic planes, all acting cooperatively decide the final product morphology. Room temperature photoluminescence (PL) spectra of this rod like structures exhibits a weak ultraviolet (UV) emission peak at around 380 nm and a broad green emission peak in the 505 nm regime. An estimate of the sensing parameters against dispensed target molecules highlighted the potential for the nanoprisms as an effective volatile sensing material. The Sn-doped ZnO nanostructures with unique prismatic morphology may find important applications in various chemical sensors as well as other potential nanodevices.

Keywords: gas sensor, HRTEM, photoluminescence, ultraviolet, zinc oxide

Procedia PDF Downloads 240
182 Dissocial Personality in Adolescents

Authors: Tsirekidze M., Aprasidze T.

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Introduction: The problem of dissocial behavior is at the heart of the social sciences and psychiatry; however, it should be noted that its psychiatric aspect is little studied, and some issues of the problem are still controversial. This is complicated by the diversity of terminological concepts in defining “dissocial behavior”, “behavioral disorder”, “abnormal behavior”, “deviant behavior”, “delinquent behavior”, etc. In literature, there is no comprehensive definition of the essence of dissociative behavior. Numerous attempts to systematize dissociative disorders should also be considered unsatisfactory, which is primarily related to the lack of solid criteria for defining this group of disorders. According to the clinical classification, dissocial behavior is divided into psychotic and non-psychotic forms. Such differentiation is conditional in nature since it is not always possible to draw precise, clear distinctions between these forms, and in addition, there is a transition of a behavior disorder or so-called intermediate forms. One group of authors distinguishes two main forms of deviant behavior in terms of both theoretical and practical significance - non-pathological and pathological. In recent years, especially, the non-pathological form of behavior disorder has become topical. It refers to a large group of forms of deviant behavior, the emergence of which is associated with psychologically full-fledged reactions of children and adolescents to stressful situations and extreme conditions. According to the authors, its concept is understandable-it is difficult to draw a line between psychologically understandable reactions and psychogenically induced reactive states. In addition, the concept of "normal" child and adolescent is, to some extent, a vague concept, as in medicine, any definition of the norm. From a practical (more precisely, pragmatic) point of view, the term "abnormal behavioral disorder" undoubtedly makes sense, especially for the purpose of forensic psychiatric examination. Non-pathological deviation mainly includes transient situational reactions, microsocial-pedagogical backwardness, and character accentuation.Deviant behavior was predominantly manifested in a non-pathological form, which, in our opinion, is due to the difficult socio-economic situation of the country, moral-ethical deprivation, and expressed frustration. By itself, society is an indicator of deviation. Add to this situation complicated factors such as micro-social-pedagogical leave, unfavorable family environment, and parenting defects. Consideration is also given to the connection of acceptable deviation with the personal structural features of the adolescent. Aim: The topic of our discussion is the dissocial behavior of the non-psychotic register. Methods: We surveyed 120 adolescents with deviant behaviors. 61% of them were diagnosed with various neuropsychiatric disorders. Results: Abnormal forms of deviant behavior were observed in 13%, and non-pathological forms in -69%. A combination of non-pathological and pathological forms was present in 10% of cases. In the case of non-pathological deviation, microsocial-pedagogical acceptance was revealed in 62%, character accentuation in 22%; during the pathological forms, pathological reactions were observed in 21%, and abnormal formation of the person -21%. Conclusion: It should be emphasized that in case of any of the above defects, if the so-called family psychosis, and medical and pedagogical habilitation measures for the adolescent, it is quite possible to prevent the abnormal development of the child's personality, correct his character, regulate behavior and develop positive labor-social relations.

Keywords: dissocial personality, deviant behavior, dissocial, delinquent behavior

Procedia PDF Downloads 220
181 Cultural Heritage, Urban Planning and the Smart City in Indian Context

Authors: Paritosh Goel

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The conservation of historic buildings and historic Centre’s over recent years has become fully encompassed in the planning of built-up areas and their management following climate changes. The approach of the world of restoration, in the Indian context on integrated urban regeneration and its strategic potential for a smarter, more sustainable and socially inclusive urban development introduces, for urban transformations in general (historical centers and otherwise), the theme of sustainability. From this viewpoint, it envisages, as a primary objective, a real “green, ecological or environmental” requalification of the city through interventions within the main categories of sustainability: mobility, energy efficiency, use of sources of renewable energy, urban metabolism (waste, water, territory, etc.) and natural environment. With this the concept of a “resilient city” is also introduced, which can adapt through progressive transformations to situations of change which may not be predictable, behavior that the historical city has always been able to express. Urban planning on the other hand, has increasingly focused on analyses oriented towards the taxonomic description of social/economic and perceptive parameters. It is connected with human behavior, mobility and the characterization of the consumption of resources, in terms of quantity even before quality to inform the city design process, which for ancient fabrics, and mainly affects the public space also in its social dimension. An exact definition of the term “smart city” is still essentially elusive, since we can attribute three dimensions to the term: a) That of a virtual city, evolved based on digital networks and web networks b) That of a physical construction determined by urban planning based on infrastructural innovation, which in the case of historic Centre’s implies regeneration that stimulates and sometimes changes the existing fabric; c) That of a political and social/economic project guided by a dynamic process that provides new behavior and requirements of the city communities that orients the future planning of cities also through participation in their management. This paper is a preliminary research into the connections between these three dimensions applied to the specific case of the fabric of ancient cities with the aim of obtaining a scientific theory and methodology to apply to the regeneration of Indian historical Centre’s. The Smart city scheme if contextualize with heritage of the city it can be an initiative which intends to provide a transdisciplinary approach between various research networks (natural sciences, socio-economics sciences and humanities, technological disciplines, digital infrastructures) which are united in order to improve the design, livability and understanding of urban environment and high historical/cultural performance levels.

Keywords: historical cities regeneration, sustainable restoration, urban planning, smart cities, cultural heritage development strategies

Procedia PDF Downloads 281
180 Solar Liquid Desiccant Regenerator for Two Stage KCOOH Based Fresh Air Dehumidifier

Authors: M. V. Rane, Tareke Tekia

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Liquid desiccant based fresh air dehumidifiers can be gainfully deployed for air-conditioning, agro-produce drying and in many industrial processes. Regeneration of liquid desiccant can be done using direct firing, high temperature waste heat or solar energy. Solar energy is clean and available in abundance; however, it is costly to collect. A two stage liquid desiccant fresh air dehumidification system can offer Coefficient of Performance (COP), in the range of 1.6 to 2 for comfort air conditioning applications. High COP helps reduce the size and cost of collectors required. Performance tests on high temperature regenerator of a two stage liquid desiccant fresh air dehumidifier coupled with seasonally tracked flat plate like solar collector will be presented in this paper. The two stage fresh air dehumidifier has four major components: High Temperature Regenerator (HTR), Low Temperature Regenerator (LTR), High and Low Temperature Solution Heat Exchangers and Fresh Air Dehumidifier (FAD). This open system can operate at near atmospheric pressure in all the components. These systems can be simple, maintenance-free and scalable. Environmentally benign, non-corrosive, moderately priced Potassium Formate, KCOOH, is used as a liquid desiccant. Typical KCOOH concentration in the system is expected to vary between 65 and 75%. Dilute liquid desiccant at 65% concentration exiting the fresh air dehumidifier will be pumped and preheated in solution heat exchangers before entering the high temperature solar regenerator. In the solar collector, solution will be regenerated to intermediate concentration of 70%. Steam and saturated solution exiting the solar collector array will be separated. Steam at near atmospheric pressure will then be used to regenerate the intermediate concentration solution up to a concentration of 75% in a low temperature regenerator where moisture vaporized be released in to atmosphere. Condensed steam can be used as potable water after adding a pinch of salt and some nutrient. Warm concentrated liquid desiccant will be routed to solution heat exchanger to recycle its heat to preheat the weak liquid desiccant solution. Evacuated glass tube based seasonally tracked solar collector is used for regeneration of liquid desiccant at high temperature. Temperature of regeneration for KCOOH is 133°C at 70% concentration. The medium temperature collector was designed for temperature range of 100 to 150°C. Double wall polycarbonate top cover helps reduce top losses. Absorber integrated heat storage helps stabilize the temperature of liquid desiccant exiting the collectors during intermittent cloudy conditions, and extends the operation of the system by couple of hours beyond the sunshine hours. This solar collector is light in weight, 12 kg/m2 without absorber integrated heat storage material, and 27 kg/m2 with heat storage material. Cost of the collector is estimated to be 10,000 INR/m2. Theoretical modeling of the collector has shown that the optical efficiency is 62%. Performance test of regeneration of KCOOH will be reported.

Keywords: solar, liquid desiccant, dehumidification, air conditioning, regeneration

Procedia PDF Downloads 348
179 Low- and High-Temperature Methods of CNTs Synthesis for Medicine

Authors: Grzegorz Raniszewski, Zbigniew Kolacinski, Lukasz Szymanski, Slawomir Wiak, Lukasz Pietrzak, Dariusz Koza

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One of the most promising area for carbon nanotubes (CNTs) application is medicine. One of the most devastating diseases is cancer. Carbon nanotubes may be used as carriers of a slowly released drug. It is possible to use of electromagnetic waves to destroy cancer cells by the carbon nanotubes (CNTs). In our research we focused on thermal ablation by ferromagnetic carbon nanotubes (Fe-CNTs). In the cancer cell hyperthermia functionalized carbon nanotubes are exposed to radio frequency electromagnetic field. Properly functionalized Fe-CNTs join the cancer cells. Heat generated in nanoparticles connected to nanotubes warm up nanotubes and then the target tissue. When the temperature in tumor tissue exceeds 316 K the necrosis of cancer cells may be observed. Several techniques can be used for Fe-CNTs synthesis. In our work, we use high-temperature methods where arc-discharge is applied. Low-temperature systems are microwave plasma with assisted chemical vapor deposition (MPCVD) and hybrid physical-chemical vapor deposition (HPCVD). In the arc discharge system, the plasma reactor works with a pressure of He up to 0,5 atm. The electric arc burns between two graphite rods. Vapors of carbon move from the anode, through a short arc column and forms CNTs which can be collected either from the reactor walls or cathode deposit. This method is suitable for the production of multi-wall and single-wall CNTs. A disadvantage of high-temperature methods is a low purification, short length, random size and multi-directional distribution. In MPCVD system plasma is generated in waveguide connected to the microwave generator. Then containing carbon and ferromagnetic elements plasma flux go to the quartz tube. The additional resistance heating can be applied to increase the reaction effectiveness and efficiency. CNTs nucleation occurs on the quartz tube walls. It is also possible to use substrates to improve carbon nanotubes growth. HPCVD system involves both chemical decomposition of carbon containing gases and vaporization of a solid or liquid source of catalyst. In this system, a tube furnace is applied. A mixture of working and carbon-containing gases go through the quartz tube placed inside the furnace. As a catalyst ferrocene vapors can be used. Fe-CNTs may be collected then either from the quartz tube walls or on the substrates. Low-temperature methods are characterized by higher purity product. Moreover, carbon nanotubes from tested CVD systems were partially filled with the iron. Regardless of the method of Fe-CNTs synthesis the final product always needs to be purified for applications in medicine. The simplest method of purification is an oxidation of the amorphous carbon. Carbon nanotubes dedicated for cancer cell thermal ablation need to be additionally treated by acids for defects amplification on the CNTs surface what facilitates biofunctionalization. Application of ferromagnetic nanotubes for cancer treatment is a promising method of fighting with cancer for the next decade. Acknowledgment: The research work has been financed from the budget of science as a research project No. PBS2/A5/31/2013

Keywords: arc discharge, cancer, carbon nanotubes, CVD, thermal ablation

Procedia PDF Downloads 449
178 Biodsorption as an Efficient Technology for the Removal of Phosphate, Nitrate and Sulphate Anions in Industrial Wastewater

Authors: Angel Villabona-Ortíz, Candelaria Tejada-Tovar, Andrea Viera-Devoz

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Wastewater treatment is an issue of vital importance in these times where the impacts of human activities are most evident, which have become essential tasks for the normal functioning of society. However, they put entire ecosystems at risk by time destroying the possibility of sustainable development. Various conventional technologies are used to remove pollutants from water. Agroindustrial waste is the product with the potential to be used as a renewable raw material for the production of energy and chemical products, and their use is beneficial since products with added value are generated from materials that were not used before. Considering the benefits that the use of residual biomass brings, this project proposes the use of agro-industrial residues from corn crops for the production of natural adsorbents whose purpose is aimed at the remediation of contaminated water bodies with large loads of nutrients. The adsorption capacity of two biomaterials obtained from the processing of corn stalks was evaluated by batch system tests. Biochar impregnated with sulfuric acid and thermally activated was synthesized. On the other hand, the cellulose was extracted from the corn stalks and chemically modified with cetyltrimethylammonium chloride in order to quaternize the surface of the adsorbent. The adsorbents obtained were characterized by thermogravimetric analysis (TGA), scanning electron microscopy (SEM), infrared spectrometry with Fourier Transform (FTIR), analysis by Brunauer, Emmett and Teller method (BET) and X-ray Diffraction analysis ( XRD), which showed favorable characteristics for the cellulose extraction process. Higher adsorption capacities of the nutrients were obtained with the use of biochar, with phosphate being the anion with the best removal percentages. The effect of the initial adsorbate concentration was evaluated, with which it was shown that the Freundlich isotherm better describes the adsorption process in most systems. The adsorbent-phosphate / nitrate systems fit better to the Pseudo Primer Order kinetic model, while the adsorbent-sulfate systems showed a better fit to the Pseudo second-order model, which indicates that there are both physical and chemical interactions in the process. Multicomponent adsorption tests revealed that phosphate anions have a higher affinity for both adsorbents. On the other hand, the thermodynamic parameters standard enthalpy (ΔH °) and standard entropy (ΔS °) with negative results indicate the exothermic nature of the process, whereas the ascending values of standard Gibbs free energy (ΔG °). The adsorption process of anions with biocarbon and modified cellulose is spontaneous and exothermic. The use of the evaluated biomateriles is recommended for the treatment of industrial effluents contaminated with sulfate, nitrate and phosphate anions.

Keywords: adsorption, biochar, modified cellulose, corn stalks

Procedia PDF Downloads 182
177 Interactions between Sodium Aerosols and Fission Products: A Theoretical Chemistry and Experimental Approach

Authors: Ankita Jadon, Sidi Souvi, Nathalie Girault, Denis Petitprez

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Safety requirements for Generation IV nuclear reactor designs, especially the new generation sodium-cooled fast reactors (SFR) require a risk-informed approach to model severe accidents (SA) and their consequences in case of outside release. In SFRs, aerosols are produced during a core disruptive accident when primary system sodium is ejected into the containment and burn in contact with the air; producing sodium aerosols. One of the key aspects of safety evaluation is the in-containment sodium aerosol behavior and their interaction with fission products. The study of the effects of sodium fires is essential for safety evaluation as the fire can both thermally damage the containment vessel and cause an overpressurization risk. Besides, during the fire, airborne fission product first dissolved in the primary sodium can be aerosolized or, as it can be the case for fission products, released under the gaseous form. The objective of this work is to study the interactions between sodium aerosols and fission products (Iodine, toxic and volatile, being the primary concern). Sodium fires resulting from an SA would produce aerosols consisting of sodium peroxides, hydroxides, carbonates, and bicarbonates. In addition to being toxic (in oxide form), this aerosol will then become radioactive. If such aerosols are leaked into the environment, they can pose a danger to the ecosystem. Depending on the chemical affinity of these chemical forms with fission products, the radiological consequences of an SA leading to containment leak tightness loss will also be affected. This work is split into two phases. Firstly, a method to theoretically understand the kinetics and thermodynamics of the heterogeneous reaction between sodium aerosols and fission products: I2 and HI are proposed. Ab-initio, density functional theory (DFT) calculations using Vienna ab-initio simulation package are carried out to develop an understanding of the surfaces of sodium carbonate (Na2CO3) aerosols and hence provide insight on its affinity towards iodine species. A comprehensive study of I2 and HI adsorption, as well as bicarbonate formation on the calculated lowest energy surface of Na2CO3, was performed which provided adsorption energies and description of the optimized configuration of adsorbate on the stable surface. Secondly, the heterogeneous reaction between (I2)g and Na2CO3 aerosols were investigated experimentally. To study this, (I2)g was generated by heating a permeation tube containing solid I2, and, passing it through a reaction chamber containing Na2CO3 aerosol deposit. The concentration of iodine was then measured at the exit of the reaction chamber. Preliminary observations indicate that there is an effective uptake of (I2)g on Na2CO3 surface, as suggested by our theoretical chemistry calculations. This work is the first step in addressing the gaps in knowledge of in-containment and atmospheric source term which are essential aspects of safety evaluation of SFR SA. In particular, this study is aimed to determine and characterize the radiological and chemical source term. These results will then provide useful insights for the developments of new models to be implemented in integrated computer simulation tool to analyze and evaluate SFR safety designs.

Keywords: iodine adsorption, sodium aerosols, sodium cooled reactor, DFT calculations, sodium carbonate

Procedia PDF Downloads 215
176 Cloning and Expression a Gene of β-Glucosidase from Penicillium echinulatum in Pichia pastoris

Authors: Amanda Gregorim Fernandes, Lorena Cardoso Cintra, Rosalia Santos Amorim Jesuino, Fabricia Paula De Faria, Marcio José Poças Fonseca

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Bioethanol is one of the most promising biofuels and able to replace fossil fuels and reduce its different environmental impacts and can be generated from various agroindustrial waste. The Brazil is in first place in bioethanol production to be the largest producer of sugarcane. The bagasse sugarcane (SCB) has lignocellulose which is composed of three major components: cellulose, hemicellulose and lignin. Cellulose is a homopolymer of glucose units connected by glycosidic linkages. Among all species of Penicillium, Penicillium echinulatum has been the focus of attention because they produce high quantities of cellulase and the mutant strain 9A02S1 produces higher enzyme levels compared to the wild. Among the cellulases, the cellobiohydrolases enzymes are the main components of the cellulolytic system of fungi, and are also responsible for most of the potential hydrolytic in enzyme cocktails for the industrial processing of plant biomass and several cellobiohydrolases Penicillium had higher specific activity against cellulose compared to CBH I from Trichoderma reesei. This fact makes it an interesting pattern for higher yields in the enzymatic hydrolysis, and also they are important enzymes in the hydrolysis of crystalline regions of cellulose. Therefore, finding new and more active enzymes become necessary. Meanwhile, β-glycosidases act on soluble substrates and are highly dependent on cellobiohydrolases and endoglucanases action to provide the substrate in the hydrolysis of the biomass, but the cellobiohydrolases and endoglucanases are highly dependent β-glucosidases to maintain efficient hydrolysis. Thus, there is a need to understand the structure-function relationships that govern the catalytic activity of cellulolytic enzymes to elucidate its mechanism of action and optimize its potential as industrial biocatalysts. To evaluate the enzyme β-glucosidase of Penicillium echinulatum (PeBGL1) the gene was synthesized from the assembly sequence from a library in induction conditions and then the PeBGL1 gene was cloned in the vector pPICZαA and transformed into P. pastoris GS115. After processing, the producers of PeBGL1 were analyzed for enzyme activity and protein profile where a band of approximately 100 kDa was viewed. It was also carried out the zymogram. In partial characterization it was determined optimum temperature of 50°C and optimum pH of 6,5. In addition, to increase the secreted recombinant PeBGL1 production by Pichia pastoris, three parameters of P. pastoris culture medium were analysed: methanol, nitrogen source concentrations and the inoculum size. A 23 factorial design was effective in achieving the optimum condition. Altogether, these results point to the potential application of this P. echinulatum β-glucosidase in hydrolysis of cellulose for the production of bioethanol.

Keywords: bioethanol, biotechnology, beta-glucosidase, penicillium echinulatum

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175 The Perceptions of Parents Regarding the Appropriateness of the Early Childhood Financial Literacy Program for Children 3 to 6 Years of Age Presented at an Early Childhood Facility in South Africa: A Case Study

Authors: M. Naude, R. Joubert, A. du Plessis, S. Pelser, M. Trollip

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Context: The study focuses on the perceptions of South African parents and teachers regarding a play-based financial literacy program for children aged 3 to 6 years at an early childhood facility. It emphasizes the importance of early interventions in financial education to reduce poverty and inequality. Research Aim: To explore how parental involvement in teaching money management concepts to young children can support financial literacy education both at school and at home. Methodology: A qualitative deductive case study was conducted at a South African early childhood facility involving 90 children, their teachers and their families. Thematic content analysis of online survey responses and focus group discussions with teachers were used to identify patterns and themes related to participants’ perceptions of the financial literacy program. Validity: The study's validity and reproducibility are ensured by the depth and honesty of the data, participant involvement, and the inquirer's objectivity. Reliability aligns with the interpretive paradigm of this study, while transparency in data gathering and analysis enhances its trustworthiness. Credibility is further supported by using two triangulation methods: focus group interviews with teachers and open-ended questionnaires from parents. Findings: Parents reported overall satisfaction with the program and highlighted the development of essential money management skills in their children. They emphasized the collaborative role of home and school environments in fostering financial literacy in early childhood. Teachers reported that communication and interaction with the parents increased and grew. Healthy and positive relationships were established between the teachers and the parents which contributed to the success of the classroom financial literacy program. Theoretical Importance: The study underscores the significance of play-based financial literacy education in early childhood and the critical role of parental involvement in reinforcing money management concepts. It contributes to laying a solid foundation for children's future financial well-being. Data Collection: Data was collected through an online survey administered to parents of children participating in the financial literacy program over a period of 10 weeks. Focus group discussions were utilized with the teachers of each class after the conclusion of the program. Analysis Procedures: Thematic content analysis was applied to the survey responses to identify patterns, themes, and insights related to the participants’ perceptions of the program's effectiveness in teaching money management concepts to young children. Question Addressed: How does parental involvement in teaching money management concepts to young children support financial literacy education in early childhood? Conclusion: The study highlights the positive impact of a play-based financial literacy program for children aged 3 to 6 years and underscores the importance of collaboration between home and school environments in fostering financial literacy skills.

Keywords: early childhood, financial literacy, money management, parent involvement, play-based learning, South Africa

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174 Rheolaser: Light Scattering Characterization of Viscoelastic Properties of Hair Cosmetics That Are Related to Performance and Stability of the Respective Colloidal Soft Materials

Authors: Heitor Oliveira, Gabriele De-Waal, Juergen Schmenger, Lynsey Godfrey, Tibor Kovacs

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Rheolaser MASTER™ makes use of multiple scattering of light, caused by scattering objects in a continuous medium (such as droplets and particles in colloids), to characterize the viscoelasticity of soft materials. It offers an alternative to conventional rheometers to characterize viscoelasticity of products such as hair cosmetics. Up to six simultaneous measurements at controlled temperature can be carried out simultaneously (10-15 min), and the method requires only minor sample preparation work. Conversely to conventional rheometer based methods, no mechanical stress is applied to the material during the measurements. Therefore, the properties of the exact same sample can be monitored over time, like in aging and stability studies. We determined the elastic index (EI) of water/emulsion mixtures (1 ≤ fat alcohols (FA) ≤ 5 wt%) and emulsion/gel-network mixtures (8 ≤ FA ≤ 17 wt%) and compared with the elastic/sorage mudulus (G’) for the respective samples using a TA conventional rheometer with flat plates geometry. As expected, it was found that log(EI) vs log(G’) presents a linear behavior. Moreover, log(EI) increased in a linear fashion with solids level in the entire range of compositions (1 ≤ FA ≤ 17 wt%), while rheometer measurements were limited to samples down to 4 wt% solids level. Alternatively, a concentric cilinder geometry would be required for more diluted samples (FA > 4 wt%) and rheometer results from different sample holder geometries are not comparable. The plot of the rheolaser output parameters solid-liquid balance (SLB) vs EI were suitable to monitor product aging processes. These data could quantitatively describe some observations such as formation of lumps over aging time. Moreover, this method allowed to identify that the different specifications of a key raw material (RM < 0.4 wt%) in the respective gel-network (GN) product has minor impact on product viscoelastic properties and it is not consumer perceivable after a short aging time. Broadening of a RM spec range typically has a positive impact on cost savings. Last but not least, the photon path length (λ*)—proportional to droplet size and inversely proportional to volume fraction of scattering objects, accordingly to the Mie theory—and the EI were suitable to characterize product destabilization processes (e.g., coalescence and creaming) and to predict product stability about eight times faster than our standard methods. Using these parameters we could successfully identify formulation and process parameters that resulted in unstable products. In conclusion, Rheolaser allows quick and reliable characterization of viscoelastic properties of hair cosmetics that are related to their performance and stability. It operates in a broad range of product compositions and has applications spanning from the formulation of our hair cosmetics to fast release criteria in our production sites. Last but not least, this powerful tool has positive impact on R&D development time—faster delivery of new products to the market—and consequently on cost savings.

Keywords: colloids, hair cosmetics, light scattering, performance and stability, soft materials, viscoelastic properties

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173 Establishing Feedback Partnerships in Higher Education: A Discussion of Conceptual Framework and Implementation Strategies

Authors: Jessica To

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Feedback is one of the powerful levers for enhancing students’ performance. However, some students are under-engaged with feedback because they lack responsibility for feedback uptake. To resolve this conundrum, recent literature proposes feedback partnerships in which students and teachers share the power and responsibilities to co-construct feedback. During feedback co-construction, students express feedback needs to teachers, and teachers respond to individuals’ needs in return. Though this approach can increase students’ feedback ownership, its application is lagging as the field lacks conceptual clarity and implementation guide. This presentation aims to discuss the conceptual framework of feedback partnerships and feedback co-construction strategies. It identifies the components of feedback partnerships and strategies which could facilitate feedback co-construction. A systematic literature review was conducted to answer the questions. The literature search was performed using ERIC, PsycINFO, and Google Scholar with the keywords “assessment partnership”, “student as partner,” and “feedback engagement”. No time limit was set for the search. The inclusion criteria encompassed (i) student-teacher partnerships in feedback, (ii) feedback engagement in higher education, (iii) peer-reviewed publications, and (iv) English as the language of publication. Those without addressing conceptual understanding and implementation strategies were excluded. Finally, 65 publications were identified and analysed using thematic analysis. For the procedure, the texts relating to the questions were first extracted. Then, codes were assigned to summarise the ideas of the texts. Upon subsuming similar codes into themes, four themes emerged: students’ responsibilities, teachers’ responsibilities, conditions for partnerships development, and strategies. Their interrelationships were examined iteratively for framework development. Establishing feedback partnerships required different responsibilities of students and teachers during feedback co-construction. Students needed to self-evaluate performance against task criteria, identify inadequacies and communicate their needs to teachers. During feedback exchanges, they interpreted teachers’ comments, generated self-feedback through reflection, and co-developed improvement plans with teachers. Teachers had to increase students’ understanding of criteria and evaluation skills and create opportunities for students’ expression of feedback needs. In feedback dialogue, teachers responded to students’ needs and advised on the improvement plans. Feedback partnerships would be best grounded in an environment with trust and psychological safety. Four strategies could facilitate feedback co-construction. First, students’ understanding of task criteria could be increased by rubrics explanation and exemplar analysis. Second, students could sharpen evaluation skills if they participated in peer review and received teacher feedback on the quality of peer feedback. Third, provision of self-evaluation checklists and prompts and teacher modeling of self-assessment process could aid students in articulating feedback needs. Fourth, the trust could be fostered when teachers explained the benefits of feedback co-construction, showed empathy, and provided personalised comments in dialogue. Some strategies were applied in interactive cover sheets in which students performed self-evaluation and made feedback requests on a cover sheet during assignment submission, followed by teachers’ response to individuals’ requests. The significance of this presentation lies in unpacking the conceptual framework of feedback partnerships and outlining feedback co-construction strategies. With a solid foundation in theory and practice, researchers and teachers could better enhance students’ engagement with feedback.

Keywords: conceptual framework, feedback co-construction, feedback partnerships, implementation strategies

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172 Reduced General Dispersion Model in Cylindrical Coordinates and Isotope Transient Kinetic Analysis in Laminar Flow

Authors: Masood Otarod, Ronald M. Supkowski

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This abstract discusses a method that reduces the general dispersion model in cylindrical coordinates to a second order linear ordinary differential equation with constant coefficients so that it can be utilized to conduct kinetic studies in packed bed tubular catalytic reactors at a broad range of Reynolds numbers. The model was tested by 13CO isotope transient tracing of the CO adsorption of Boudouard reaction in a differential reactor at an average Reynolds number of 0.2 over Pd-Al2O3 catalyst. Detailed experimental results have provided evidence for the validity of the theoretical framing of the model and the estimated parameters are consistent with the literature. The solution of the general dispersion model requires the knowledge of the radial distribution of axial velocity. This is not always known. Hence, up until now, the implementation of the dispersion model has been largely restricted to the plug-flow regime. But, ideal plug-flow is impossible to achieve and flow regimes approximating plug-flow leave much room for debate as to the validity of the results. The reduction of the general dispersion model transpires as a result of the application of a factorization theorem. Factorization theorem is derived from the observation that a cross section of a catalytic bed consists of a solid phase across which the reaction takes place and a void or porous phase across which no significant measure of reaction occurs. The disparity in flow and the heterogeneity of the catalytic bed cause the concentration of reacting compounds to fluctuate radially. These variabilities signify the existence of radial positions at which the radial gradient of concentration is zero. Succinctly, factorization theorem states that a concentration function of axial and radial coordinates in a catalytic bed is factorable as the product of the mean radial cup-mixing function and a contingent dimensionless function. The concentration of adsorbed compounds are also factorable since they are piecewise continuous functions and suffer the same variability but in the reverse order of the concentration of mobile phase compounds. Factorability is a property of packed beds which transforms the general dispersion model to an equation in terms of the measurable mean radial cup-mixing concentration of the mobile phase compounds and mean cross-sectional concentration of adsorbed species. The reduced model does not require the knowledge of the radial distribution of the axial velocity. Instead, it is characterized by new transport parameters so denoted by Ωc, Ωa, Ωc, and which are respectively denominated convection coefficient cofactor, axial dispersion coefficient cofactor, and radial dispersion coefficient cofactor. These cofactors adjust the dispersion equation as compensation for the unavailability of the radial distribution of the axial velocity. Together with the rest of the kinetic parameters they can be determined from experimental data via an optimization procedure. Our data showed that the estimated parameters Ωc, Ωa Ωr, are monotonically correlated with the Reynolds number. This is expected to be the case based on the theoretical construct of the model. Computer generated simulations of methanation reaction on nickel provide additional support for the utility of the newly conceptualized dispersion model.

Keywords: factorization, general dispersion model, isotope transient kinetic, partial differential equations

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171 Planning Fore Stress II: Study on Resiliency of New Architectural Patterns in Urban Scale

Authors: Amir Shouri, Fereshteh Tabe

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Master planning and urban infrastructure’s thoughtful and sequential design strategies will play the major role in reducing the damages of natural disasters, war and or social/population related conflicts for cities. Defensive strategies have been revised during the history of mankind after having damages from natural depressions, war experiences and terrorist attacks on cities. Lessons learnt from Earthquakes, from 2 world war casualties in 20th century and terrorist activities of all times. Particularly, after Hurricane Sandy of New York in 2012 and September 11th attack on New York’s World Trade Centre (WTC) in 21st century, there have been series of serious collaborations between law making authorities, urban planners and architects and defence related organizations to firstly, getting prepared and/or prevent such activities and secondly, reduce the human loss and economic damages to minimum. This study will work on developing a model of planning for New York City, where its citizens will get minimum impacts in threat-full time with minimum economic damages to the city after the stress is passed. The main discussion in this proposal will focus on pre-hazard, hazard-time and post-hazard transformative policies and strategies that will reduce the “Life casualties” and will ease “Economic Recovery” in post-hazard conditions. This proposal is going to scrutinize that one of the key solutions in this path might be focusing on all overlaying possibilities on architectural platforms of three fundamental infrastructures, the transportation, the power related sources and defensive abilities on a dynamic-transformative framework that will provide maximum safety, high level of flexibility and fastest action-reaction opportunities in stressful periods of time. “Planning Fore Stress” is going to be done in an analytical, qualitative and quantitative work frame, where it will study cases from all over the world. Technology, Organic Design, Materiality, Urban forms, city politics and sustainability will be discussed in deferent cases in international scale. From the modern strategies of Copenhagen for living friendly with nature to traditional approaches of Indonesian old urban planning patterns, the “Iron Dome” of Israel to “Tunnels” in Gaza, from “Ultra-high-performance quartz-infused concrete” of Iran to peaceful and nature-friendly strategies of Switzerland, from “Urban Geopolitics” in cities, war and terrorism to “Design of Sustainable Cities” in the world, will all be studied with references and detailed look to analysis of each case in order to propose the most resourceful, practical and realistic solutions to questions on “New City Divisions”, “New City Planning and social activities” and “New Strategic Architecture for Safe Cities”. This study is a developed version of a proposal that was announced as winner at MoMA in 2013 in call for ideas for Rockaway after Sandy Hurricane took place.

Keywords: urban scale, city safety, natural disaster, war and terrorism, city divisions, architecture for safe cities

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170 A Case Report: The Role of Gut Directed Hypnotherapy in Resolution of Irritable Bowel Syndrome in a Medication Refractory Pediatric Male Patient

Authors: Alok Bapatla, Pamela Lutting, Mariastella Serrano

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Background: Irritable Bowel Syndrome (IBS) is a functional gastrointestinal disorder characterized by abdominal pain associated with altered bowel habits in the absence of an underlying organic cause. Although the exact etiology of IBS is not fully understood, one of the leading theories postulates a pathology within the Brain-Gut Axis that leads to an overall increase in gastrointestinal sensitivity and pejorative changes in gastrointestinal motility. Research and clinical practice have shown that Gut Directed Hypnotherapy (GDH) has a beneficial clinical role in improving Mind-Gut control and thereby comorbid conditions such as anxiety, abdominal pain, constipation, and diarrhea. Aims: This study presents a 17-year old male with underlying anxiety and a one-year history of IBS-Constipation Predominant Subtype (IBS-C), who has demonstrated impressive improvement of symptoms following GDH treatment following refractory trials with medications including bisacodyl, senna, docusate, magnesium citrate, lubiprostone, linaclotide. Method: The patient was referred to a licensed clinical psychologist specializing in clinical hypnosis and cognitive-behavioral therapy (CBT), who implemented “The Standardized Hypnosis Protocol for IBS” developed by Dr. Olafur S. Palsson, Psy.D at the University of North Carolina at Chapel Hill. The hypnotherapy protocol consisted of a total of seven weekly 45-minute sessions supplemented with a 20-minute audio recording to be listened to once daily. Outcome variables included the GAD-7, PHQ-9 and DCI-2, as well as self-ratings (ranging 0-10) for pain (intensity and frequency), emotional distress about IBS symptoms, and overall emotional distress. All variables were measured at intake prior to administration of the hypnosis protocol and at the conclusion of the hypnosis treatment. A retrospective IBS Questionnaire (IBS Severity Scoring System) was also completed at the conclusion of the GDH treatment for pre-and post-test ratings of clinical symptoms. Results: The patient showed improvement in all outcome variables and self-ratings, including abdominal pain intensity, frequency of abdominal pain episodes, emotional distress relating to gut issues, depression, and anxiety. The IBS Questionnaire showed a significant improvement from a severity score of 400 (defined as severe) prior to GDH intervention compared to 55 (defined as complete resolution) at four months after the last session. IBS Questionnaire subset questions that showed a significant score improvement included abdominal pain intensity, days of pain experienced per 10 days, satisfaction with bowel habits, and overall interference of life affected by IBS symptoms. Conclusion: This case supports the existing research literature that GDH has a significantly beneficial role in improving symptoms in patients with IBS. Emphasis is placed on the numerical results of the IBS Questionnaire scoring, which reflects a patient who initially suffered from severe IBS with failed response to multiple medications, who subsequently showed full and sustained resolution

Keywords: pediatrics, constipation, irritable bowel syndrome, hypnotherapy, gut-directed hypnosis

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