Search results for: particles’ forces

Authors: William Creighton, Jan Smitheram

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Queer discourse has been tied to a middle-class, urban-centric, white approach to the discussion of queerness. In doing so, the multilayeredness of queer existence has been washed away in favour of palatable queer occupation. This paper uses design to explore a queer anti-urbanist approach to facilitate a more egalitarian architectural occupancy. Scott Herring’s work on queer anti-urbanism is key to this approach. Herring redeploys anti-urbanism from its historical understanding of open hostility, rejection and desire to destroy the city towards a mode of queer critique that counters normative ideals of homonormative metronormative gay lifestyles. He questions how queer identity has been closed down into a more diminutive frame where those who do not fit within this frame are subjected to persecution or silenced through their absence. We extend these ideas through design to ask how a queer anti-urbanist approach facilitates a more egalitarian architectural occupancy. Following a “design as research” methodology, the design outputs allow a vehicle to ask how we might live, otherwise, in architectural space. A design as research methodologically is a process of questioning, designing and reflecting – in a non-linear, iterative approach – establishes itself through three projects, each increasing in scale and complexity. Each of the three scales tackled a different body relationship. The project began exploring the relations between body to body, body to known others, and body to unknown others. Moving through increasing scales was not to privilege the objective, the public and the large scale; instead, ‘intra-scaling’ acts as a tool to re-think how scale reproduces normative ideas of the identity of space. There was a queering of scale. Through this approach, the results were an installation that brings two people together to co-author space where the installation distorts the sensory experience and forces a more intimate and interconnected experience challenging our socialized proxemics: knees might touch. To queer the home, the installation was used as a drawing device, a tool to study and challenge spatial perception, drawing convention, and as a way to process practical information about the site and existing house – the device became a tool to embrace the spontaneous. The final design proposal operates as a multi-scalar boundary-crossing through “private” and “public” to support kinship through communal labour, queer relationality and mooring. The resulting design works to set adrift bodies in a sea of sensations through a mix of pleasure programmes. To conclude, through three design proposals, this design research creates a relationship between queer anti-urbanism and design. It asserts that queering the design process and outcome allows a more inclusive way to consider place, space and belonging. The projects lend to a queer relationality and interdependence by making spaces that support the unsettled, out-of-place, but is it queer enough?

Keywords: queer, queer anti-urbanism, design as research, design

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Authors: R. Abdulrahman, A. Eardley, A. Soliman

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The proliferation in the development of mobile learning (m-learning) has played a vital role in the rapidly growing electronic learning market. This relatively new technology can help to encourage the development of in learning and to aid knowledge transfer a number of areas, by familiarizing students with innovative information and communications technologies (ICT). M-learning plays a substantial role in the deployment of learning methods for nursing students by using the Internet and portable devices to access learning resources ‘anytime and anywhere’. However, acceptance of m-learning by students is critical to the successful use of m-learning systems. Thus, there is a need to study the factors that influence student’s intention to use m-learning. This paper addresses this issue. It outlines the outcomes of a study that evaluates the unified theory of acceptance and use of technology (UTAUT) model as applied to the subject of user acceptance in relation to m-learning activity in nurse education. The model integrates the significant components across eight prominent user acceptance models. Therefore, a standard measure is introduced with core determinants of user behavioural intention. The research model extends the UTAUT in the context of m-learning acceptance by modifying and adding individual innovativeness (II) and quality of service (QoS) to the original structure of UTAUT. The paper goes on to add the factors of previous experience (of using mobile devices in similar applications) and the nursing students’ readiness (to use the technology) to influence their behavioural intentions to use m-learning. This study uses a technique called ‘convenience sampling’ which involves student volunteers as participants in order to collect numerical data. A quantitative method of data collection was selected and involves an online survey using a questionnaire form. This form contains 33 questions to measure the six constructs, using a 5-point Likert scale. A total of 42 respondents participated, all from the Nursing Institute at the Armed Forces Hospital in Saudi Arabia. The gathered data were then tested using a research model that employs the structural equation modelling (SEM), including confirmatory factor analysis (CFA). The results of the CFA show that the UTAUT model has the ability to predict student behavioural intention and to adapt m-learning activity to the specific learning activities. It also demonstrates satisfactory, dependable and valid scales of the model constructs. This suggests further analysis to confirm the model as a valuable instrument in order to evaluate the user acceptance of m-learning activity.

Keywords: mobile learning, nursing institute students’ acceptance of m-learning activity in Saudi Arabia, unified theory of acceptance and use of technology model (UTAUT), structural equation modelling (SEM)

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Authors: Xu Heng

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Since the financial crisis of 2008 and the resulting Great Recession, the number of China’s unemployed college graduate reached over 500 thousand in 2011. Following the severe situation of college graduate employment, there has been growing public concern about college graduates, especially those with the less-privileged background, and their working and living condition in metropolises. Previous studies indicate that well-educated urban migrants with less-privileged background tend to obtain temporary occupation with less financial income and lower social status. Those vulnerable young migrants are described as ‘Ant Tribe’ by some scholars. However, since the implementation of a new urbanization project, together with the relaxed Hukou system and the acceleration of socio-economic development in middle/small cities, some researchers described well-educated urban migrant’s situation and the prospect of upward social mobility in urban areas in an overly optimistic light. In order to shed more lights on the underlying tensions encountered by China’s well-educated urban migrants in their upward social mobility pursuit, this research mainly focuses on 10 well-educated urban migrants’ life trajectories between their university-to-work transition and their current situation. All selected well-educated urban migrants are young adults with rural background who have already received higher education qualification from first-tier universities of Wuhan City (capital of Hubei Province). Drawing on the in-depth interviews with 10 participants and Inspired by Lahire’s Theory of Plural Actor, this study yields the following preliminary findings; 1) For those migrants who move to super-mega cities (i.e., Beijing, Shenzhen, Guangzhou) or stay in Wuhan after college graduation, their inadequacies of economic and social capital are the structural factors which negatively influence their living condition and further shape their plan for career development. The incompatibility between the sub-fields of urban life and the disposition, which generated from their early socialization, is the main cause for marginalized position in the metropolises. 2) For those migrants who move back to middle/small cities located in their hometown regions, the inconsistency between the disposition, which generated from college life, and the organizational habitus of the workplace is the main cause for their sense of ‘fish out of water’, even though they have obtained the stable occupation of local government or state-owned enterprise. On the whole, this research illuminates how the underlying the structural forces shape well-educated urban migrants’ life trajectories and hinder their upward social mobility under the context of new urbanization project.

Keywords: life trajectory, social mobility, urbanization, well-educated urban migrant

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Authors: Vladimir Messerle, Alexandr Ustimenko, Oleg Lavrichshev

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To enhance the efficiency of solid fuels’ use, to decrease the fuel oil rate in the thermal power plants fuel balance and to minimize harmful emissions, a plasma technology of coal ignition, gasification and incineration is successfully applied. This technology is plasma thermochemical preparation of fuel for burning (PTCPF). In the framework of this concept, some portion of pulverized solid fuel (PF) is separated from the main PF flow and undergone the activation by arc plasma in a specific chamber with plasma torch – PFS. The air plasma flame is a source of heat and additional oxidation, it provides a high-temperature medium enriched with radicals, where the fuel mixture is heated, volatile components of coal are extracted, and carbon is partially gasified. This active blended fuel can ignite the main PF flow supplied into the furnace. This technology provides the boiler start-up and stabilization of PF flame and eliminates the necessity for addition of highly reactive fuel. In the report, a model of PTCPF, implemented as a program PlasmaKinTherm for the PFS calculation is described. The model combines thermodynamic and kinetic methods for describing the process of PTCPF in PFS. The numerical investigation of operational parameters of PFS depending on the electric power of the plasma generator and steam coal ash content revealed the temperature and velocity of gas and coal particles, and concentrations of PTCPF products dependences on the PFS length. Main mechanisms of PTCPF were disclosed. It was found that in the range of electric power of plasma generator from 40 to 100 kW high ash bituminous coal, having consumption 1667 kg/h is ignited stably. High level of temperature (1740 K) and concentration of combustible components (44%) at the PFS exit is a confirmation of it. Augmentation in power of plasma generator results displacement maxima temperatures and speeds of PTCPF products upstream (in the direction of the plasma source). The maximum temperature and velocity vary in a narrow range of values and practically do not depend on the power of the plasma torch. The numerical study of indicators of the process of PTCPF depending on the ash content in the range of its values 20-70% demonstrated that at the exit of PFS concentration of combustible components decreases with an increase in coal ash, the temperature of the gaseous products is increasing, and coal carbon conversion rate is increased to a maximum value when the ash content of 60%, dramatically decreasing with further increase in the ash content.

Keywords: coal, efficiency, ignition, numerical modeling, plasma generator, plasma-fuel system

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Authors: K. Graniczkowska, N. Beloglazova, S. De Saeger

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The threat of synthetic drugs is one of the most significant current drug problems worldwide. The use of drugs of abuse has increased dramatically during the past three decades. Among others, Amphetamine-Type Stimulants (ATS) are globally the second most widely used drugs after cannabis, exceeding the use of cocaine and heroin. ATS are potent central nervous system (CNS) stimulants, capable of inducing euphoric static similar to cocaine. Recreational use of ATS is widespread, even though warnings of irreversible damage of the CNS were reported. ATS pose a big problem and their production contributes to the pollution of the environment by discharging big volumes of liquid waste to sewage system. Therefore, there is a demand to develop robust and sensitive sensors that can detect ATS and their intermediates in environmental water samples. A rapid and simple test is required. Analysis of environmental water samples (which sometimes can be a harsh environment) using antibody-based tests cannot be applied. Therefore, molecular imprinted polymers (MIPs), which are known as synthetic antibodies, have been chosen for that approach. MIPs are characterized with a high mechanical and thermal stability, show chemical resistance in a broad pH range and various organic or aqueous solvents. These properties make them the preferred type of receptors for application in the harsh conditions imposed by environmental samples. To the best of our knowledge, there are no existing MIPs-based sensors toward amphetamine and its intermediates. Also not many commercial MIPs for this application are available. Therefore, the aim of this study was to compare different techniques to obtain MIPs with high specificity towards ATS and characterize them for following use in a sensing unit. MIPs against amphetamine and its intermediates were synthesized using a few different techniques, such as electro-, thermo- and UV-initiated polymerization. Different monomers, cross linkers and initiators, in various ratios, were tested to obtain the best sensitivity and polymers properties. Subsequently, specificity and selectivity were compared with commercially available MIPs against amphetamine. Different linkers, such as lipoic acid, 3-mercaptopioponic acid and tyramine were examined, in combination with several immobilization techniques, to select the best procedure for attaching particles on sensor surface. Performed experiments allowed choosing an optimal method for the intended sensor application. Stability of MIPs in extreme conditions, such as highly acidic or basic was determined. Obtained results led to the conclusion about MIPs based sensor applicability in sewage system testing.

Keywords: amphetamine type stimulants, environment, molecular imprinted polymers, MIPs, sensor

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Authors: Sayed M. Ahmed, Sawsan S. Darwish, Nagib A. Elmarzugi, Mohammad A. Al-Dosari, Mahmoud A. Adam, Nadia A. Al-Mouallimi

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Historical stone surfaces and architectural heritage may undergo unwanted changes due to the exposure to many physical and chemical deterioration factors, the innovative properties of the nano - materials can have advantageous application in the restoration and conservation of the cultural heritage with relation to the tailoring of new products for protection and consolidation of stone. The current work evaluates the effectiveness of inorganic compatible treatments; based on nanosized particles of silica (SiO2) dispersed in silicon based product, commonly used as a water-repellent/ consolidation for the construction materials affected by different kinds of decay. The nanocomposites obtained by dispersing the silica nanoparticles in polymeric matrices SILRES® BS OH 100 (solventless mixtures of ethyl silicates), in order to obtain a new nanocomposite, with hydrophobic and consolidation properties, to improve the physical and mechanical properties of the stone material. The nanocomposites obtained and pure SILRES® BS OH 100 were applied by brush Experimental stone blocks. The efficacy of the treatments has been evaluated after consolidation and artificial Thermal aging, through capillary water absorption measurements, Ultraviolet-light exposure to evaluate photo-induced and the hydrophobic effects of the treated surface, Scanning electron microscopy (SEM) examination is performed to evaluate penetration depth, re-aggregating effects of the deposited phase and the surface morphology before and after artificialaging. Sterio microscopy investigation is performed to evaluate the resistant to the effects of the erosion, acids and salts. Improving of stone mechanical properties were evaluated by compressive strength tests, colorimetric measurements were used to evaluate the optical appearance. All the results get together with the apparent effect that, silica/polymer nanocomposite is efficient material for the consolidation of artistic and architectural sandstone monuments, completely compatible, enhanced the durability of sandstone toward thermal and UV aging. In addition, the obtained nanocomposite improved the stone mechanical properties and the resistant to the effects of the erosion, acids and salts compared to the samples treated with pure SILRES® BS OH 100 without silica nanoparticles.

Keywords: colorimetric measurements, compressive strength, nanocomposites, porous stone consolidation, silica nanoparticles, sandstone

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Authors: Miguel Contreras, David Long, Will Bachman

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Background: Microscopy plays a central role in cell and developmental biology. In particular, fluorescence microscopy can be used to visualize specific cellular components and subsequently quantify their morphology through development of virtual-cell models for study of effects of mechanical forces on cells. However, there are challenges with these imaging experiments, which can make it difficult to quantify cell morphology: inconsistent results, time-consuming and potentially costly protocols, and limitation on number of labels due to spectral overlap. To address these challenges, the objective of this project is to develop an automatic computational machine learning pipeline to predict cellular components morphology for virtual-cell generation based on fluorescence cell membrane confocal z-stacks. Methods: Registered confocal z-stacks of nuclei and cell membrane of endothelial cells, consisting of 20 images each, were obtained from fluorescence confocal microscopy and normalized through software pipeline for each image to have a mean pixel intensity value of 0.5. An open source machine learning algorithm, originally developed to predict fluorescence labels on unlabeled transmitted light microscopy cell images, was trained using this set of normalized z-stacks on a single CPU machine. Through transfer learning, the algorithm used knowledge acquired from its previous training sessions to learn the new task. Once trained, the algorithm was used to predict morphology of nuclei using normalized cell membrane fluorescence images as input. Predictions were compared to the ground truth fluorescence nuclei images. Results: After one week of training, using one cell membrane z-stack (20 images) and corresponding nuclei label, results showed qualitatively good predictions on training set. The algorithm was able to accurately predict nuclei locations as well as shape when fed only fluorescence membrane images. Similar training sessions with improved membrane image quality, including clear lining and shape of the membrane, clearly showing the boundaries of each cell, proportionally improved nuclei predictions, reducing errors relative to ground truth. Discussion: These results show the potential of pre-trained machine learning algorithms to predict cell morphology using relatively small amounts of data and training time, eliminating the need of using multiple labels in immunofluorescence experiments. With further training, the algorithm is expected to predict different labels (e.g., focal-adhesion sites, cytoskeleton), which can be added to the automatic machine learning pipeline for direct input into Principal Component Analysis (PCA) for generation of virtual-cell mechanical models.

Keywords: cell morphology prediction, computational machine learning, fluorescence microscopy, virtual-cell models

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Authors: Anu Shrestha, Krassi Rumchev, Ben Mullins, Yun Zhao, Linda Selvey

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Cycling is often promoted as a means of reducing vehicular congestion, noise and greenhouse gas and air pollutant emissions in urban areas. It is also indorsed as a healthy means of transportation in terms of reducing the risk of developing a range of physical and psychological conditions. However, people who cycle regularly may not be aware that they can become exposed to high levels of Vehicular Air Pollutants (VAP) emitted by nearby traffics and therefore experience adverse health effects as a result. The study will highlight the present scenario of ambient air pollution level in different cycling routes in Perth and also highlight significant contribution to the understanding of health risks that cyclist may face from exposure to particulate air pollution. Methodology: This research was conducted in Perth, Western Austral and consisted of two groups of cyclists cycling near high (2 routes) and low (two routes) vehicular traffic roads, at high and low levels of exertion, during the cold and warm seasons. A sample size of 123 regular cyclists who cycled at least 80 km/week, aged 20-55, and non-smoker were selected for this study. There were altogether 100 male and 23 female who were asked to choose one or more routes among four different routes, and each participant cycled the route for warm or cold or both seasons. Cyclist who reported cardiovascular and other chronic health conditions (excluding asthma) were not invited into the study. Exposures to selected air pollutants were assessed by undertaking background and personal measurements alone with the measurement of heart and breathe rate of each participant. Finding: According to the preliminary study findings, the cyclists who used cycling route close to high traffic route were exposed to higher levels of measured air pollutants Nitrogen Oxide (NO₂) =0.12 ppm, sulfur dioxide (SO₂)=0.06 ppm and carbon monoxide (CO)=0.25 PPM compared to those who cycled away from busy roads. However, we measured high concentrations of particulate air pollution near one of the low traffic route which we associate with the close proximity to ferry station. Concluding Statement: As a conclusion, we recommend that cycling routes should be selected away from high traffic routes. If possible, we should also consider that if the cycling route is surrounded by the dense populated infrastructures, it can trap the pollutants and always facilitate in increasing inhalation of particle count among the cyclists.

Keywords: air pollution, carbon monoxide, cyclists' health, nitrogen dioxide, nitrogen oxide, respirable particulate matters

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Authors: Sankha Chakrabortty, Biswajit Ruj, Parimal Pal

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Methanol is one of the most important chemical products and intermediates. It can be used as a solvent, intermediate or raw material for a number of higher valued products, fuels or additives. From the last one decay, the total global demand of methanol has increased drastically which forces the scientists to produce a large amount of methanol from a renewable source to meet the global demand with a sustainable way. Different types of non-renewable based raw materials have been used for the synthesis of methanol on a large scale which makes the process unsustainable. In this circumstances, photocatalytic conversion of CO₂ into methanol under solar/UV excitation becomes a viable approach to give a sustainable production approach which not only meets the environmental crisis by recycling CO₂ to fuels but also reduces CO₂ amount from the atmosphere. Development of such sustainable production approach for CO₂ conversion into methanol still remains a major challenge in the current research comparing with conventional energy expensive processes. In this backdrop, the development of environmentally friendly materials, like photocatalyst has taken a great perspective for methanol synthesis. Scientists in this field are always concerned about finding an improved photocatalyst to enhance the photocatalytic performance. Graphene-based hybrid and composite materials with improved properties could be a better nanomaterial for the selective conversion of CO₂ to methanol under visible light (solar energy) or UV light. The present invention relates to synthesis an improved heterogeneous graphene-based photocatalyst with improved catalytic activity and surface area. Graphene with enhanced surface area is used as coupled material of copper-loaded titanium oxide to improve the electron capture and transport properties which substantially increase the photoinduced charge transfer and extend the lifetime of photogenerated charge carriers. A fast reduction method through H₂ purging has been adopted to synthesis improved graphene whereas ultrasonication based sol-gel method has been applied for the preparation of graphene coupled copper loaded titanium oxide with some enhanced properties. Prepared photocatalysts were exhaustively characterized using different characterization techniques. Effects of catalyst dose, CO₂ flow rate, reaction temperature and stirring time on the efficacy of the system in terms of methanol yield and productivity have been studied in the present study. The study shown that the newly synthesized photocatalyst with an enhanced surface resulting in a sustained productivity and yield of methanol 0.14 g/Lh, and 0.04 g/gcat respectively, after 3 h of illumination under UV (250W) at an optimum catalyst dosage of 10 g/L having 1:2:3 (Graphene: TiO₂: Cu) weight ratio.

Keywords: renewable energy, CO₂ capture, photocatalytic conversion, methanol

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Authors: Ingrid Snustad, Asmund Ervik, Anders Austegard, Amy Brunsvold, Jianying He, Zhiliang Zhang

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CO₂ capture, transport and storage (CCS) is essential to mitigate global anthropogenic CO₂ emissions. To make CCS a widely implemented technology in, e.g. the power sector, the reduction of costs is crucial. For a large cost reduction, every part of the CCS chain must contribute. By increasing the heat transfer efficiency during liquefaction of CO₂, which is a necessary step, e.g. ship transportation, the costs associated with the process are reduced. Heat transfer rates during dropwise condensation are up to one order of magnitude higher than during filmwise condensation. Dropwise condensation usually occurs on a non-wetting surface (Superlyophobic surface). The vapour condenses in discrete droplets, and the non-wetting nature of the surface reduces the adhesion forces and results in shedding of condensed droplets. This, again, results in fresh nucleation sites for further droplet condensation, effectively increasing the liquefaction efficiency. In addition, the droplets in themselves have a smaller heat transfer resistance than a liquid film, resulting in increased heat transfer rates from vapour to solid. Surface tension is a crucial parameter for dropwise condensation, due to its impact on the solid-liquid contact angle. A low surface tension usually results in a low contact angle, and again to spreading of the condensed liquid on the surface. CO₂ has very low surface tension compared to water. However, at relevant temperatures and pressures for CO₂ condensation, the surface tension is comparable to organic compounds such as pentane, a dropwise condensation of CO₂ is a completely new field of research. Therefore, knowledge of several important parameters such as contact angle and drop size distribution must be gained in order to understand the nature of the condensation. A new setup has been built to measure these relevant parameters. The main parts of the experimental setup is a pressure chamber in which the condensation occurs, and a high- speed camera. The process of CO₂ condensation is visually monitored, and one can determine the contact angle, contact angle hysteresis and hence, the surface adhesion of the liquid. CO₂ condensation on different surfaces can be analysed, e.g. copper, aluminium and stainless steel. The experimental setup is built for accurate measurements of the temperature difference between the surface and the condensing vapour and accurate pressure measurements in the vapour. The temperature will be measured directly underneath the condensing surface. The next step of the project will be to fabricate nanostructured surfaces for inducing superlyophobicity. Roughness is a key feature to achieve contact angles above 150° (limit for superlyophobicity) and controlled, and periodical roughness on the nanoscale is beneficial. Surfaces that are non- wetting towards organic non-polar liquids are candidates surface structures for dropwise condensation of CO₂.

Keywords: CCS, dropwise condensation, low surface tension liquid, superlyophobic surfaces

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Authors: Maxim Kravchenko

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The paper looks into the structure and contents of the concept of empire in the social consciousness of modern Americans. To construct the model of this socially and politically relevant concept we have conducted an experiment with respondents born and living in the USA. Empire is seen as a historic notion describing such entities as the British empire, the Russian empire, the Ottoman empire and others. It seems that the democratic regime adopted by most countries worldwide is incompatible with imperial status of a country. Yet there are countries which tend to dominate in the contemporary world and though they are not routinely referred to as empires, in many respects they are reminiscent of historical empires. Thus, the central hypothesis of the study is that the concept of empire is cultivated in some states through the intermediary of the mass media though it undergoes a certain transformation to meet the expectations of a democratic society. The transformation implies that certain components which were historically embedded in its structure are drawn to the margins of the hierarchical structure of the concept whereas other components tend to become central to the concept. This process can be referred to as restructuration of the concept of empire. To verify this hypothesis we have conducted a study which falls into two stages. First we looked into the definition of empire featured in dictionaries, the dominant conceptual components of empire are: importance, territory/lands, recognition, independence, authority/power, supreme/absolute. However, the analysis of 100 articles from American newspapers chosen at random revealed that authors rarely use the word «empire» in its basic meaning (7%). More often «empire» is used when speaking about countries, which no longer exist or when speaking about some corporations (like Apple or Google). At the second stage of the study we conducted an associative experiment with the citizens of the USA aged 19 to 45. The purpose of the experiment was to find out the dominant components of the concept of empire and to construct the model of the transformed concept. The experiment stipulated that respondents should give the first association, which crosses their mind, on reading such stimulus phrases as “strong military”, “strong economy” and others. The list of stimuli features various words and phrases associated with empire including the words representing the dominant components of the concept of empire. Then the associations provided by the respondents were classified into thematic clusters. For instance, the associations to the stimulus “strong military” were compartmentalized into three groups: 1) a country with strong military forces (North Korea, the USA, Russia, China); 2) negative impression of strong military (war, anarchy, conflict); 3) positive impression of strong military (peace, safety, responsibility). The experiment findings suggest that the concept of empire is currently undergoing a transformation which brings about a number of changes. Among them predominance of positively assessed components of the concept; emergence of two poles in the structure of the concept, that is “hero” vs. “enemy”; marginalization of any negatively assessed components.

Keywords: associative experiment, conceptual components, empire, restructurasation of the concept

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Authors: Arup Pramanik

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Most of the cities in the developing countries like Siliguri Municipal Corporation Area (SMCA) and Raiganj Municipality (RM) in West Bengal, India are changing typically in terms of demographic, economic and social relationship due to rapid pace of urbanization. The mushrooming growth of slums in SMCA and RM is the direct consequence of urbanization and migration due to regional imbalance, unbalanced growth process which is posing a serious threat to sustainable development of the country. Almost all the slums happen to be a breeding ground for poverty, negligence, and disease. Unpredictable growth of slums and poverty alleviation has now become a serious challenge to the global and national policy makers for the development of the slum dwellers. The ethical dimension of the poor in the cities like SMCA and RM stands on equal opportunities, inclusive and harmonious living without discrimination of any kind. But, the migrant slum dwellers in SMCA and RM do not possess high skill or education to enable them to find well paid employment in the formal sector and the surplus urban labour force is compelled to generate its own means of employment and survival in the informal sector. The survey data of the households has been analysedin terms of percentage, descriptive statistics which includes mean, Standard Deviation (SD), ANOVA (Mean Difference) etc., to analyse the socio economic variables of the households. The study shows that the migrant labour forces living in the slums are derived from the social security measures in both the municipal areas of SMCA and RM. The urban poor in the cities of SMCA and RM rely heavily on social capital amongst all the capital assets to help them ‘get by’ and ‘get ahead’. Despite, the slum dwellers in the study areas are vulnerable with respect to other determinants of capital assets. It is noteworthy that Indian plans of anti-poverty programmes was in a proper place even after the neo-liberal regime, where the basic idea behind the massive shift of various welfare and service oriented strategy to poverty reduction strategy for the benefit of the urban poor with the trickle down effects. But, the overall impact of the trickledown effect was unsatisfactory. The objective of the Paper is to assess the magnitude of migration and absorption in the urban labour market. Issues relating to capital formation, social security measures and the support of the Welfare State in order to meet 'Sustainable Development Goals'. This study also highlights the quality of life of urban poor migrants in terms of capital formation and livelihoods.

Keywords: migration, slums, labour market, capital formation, social security

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Authors: Fatima Zahra Mahjoubi, Abderrahim Khalidi, Mohamed Abdennouri, Omar Cherkaoui, Noureddine Barka

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Industrial effluents are one of the major causes of environmental pollution, especially effluents discharged from various dyestuff manufactures, plastic, and paper making industries. These effluents can give rise to certain hazards and environmental problems for their highly colored suspended organic solid. Dye effluents are not only aesthetic pollutants, but coloration of water by the dyes may affect photochemical activities in aquatic systems by reducing light penetration. It has been also reported that several commonly used dyes are carcinogenic and mutagenic for aquatic organisms. Therefore, removing dyes from effluents is of significant importance. Many adsorbent materials have been prepared in the removal of dyes from wastewater, including anionic clay or layered double hydroxyde. The zinc/aluminium (Zn-AlNO₃), magnesium/aluminium (Mg-AlNO₃) and nickel/aluminium (Ni-AlNO₃) layered double hydroxides (LDHs) were successfully synthesized via coprecipitation method. Samples were characterized by XRD, FTIR, TGA/DTA, TEM and pHPZC analysis. XRD patterns showed a basal spacing increase in the order of Zn-AlNO₃ (8.85Å)> Mg-AlNO₃ (7.95Å)> Ni-AlNO₃ (7.82Å). FTIR spectrum confirmed the presence of nitrate anions in the LDHs interlayer. The TEM images indicated that the Zn-AlNO3 presents circular to shaped particles with an average particle size of approximately 30 to 40 nm. Small plates assigned to sheets with hexagonal form were observed in the case of Mg-AlNO₃. Ni-AlNO₃ display nanostructured sphere in diameter between 5 and 10 nm. The LDHs were used as adsorbents for the removal of methyl orange (MO), as a model dye and for the treatment of an effluent generated by a textile factory. Adsorption experiments for MO were carried out as function of solution pH, contact time and initial dye concentration. Maximum adsorption was occurred at acidic solution pH. Kinetic data were tested using pseudo-first-order and pseudo-second-order kinetic models. The best fit was obtained with the pseudo-second-order kinetic model. Equilibrium data were correlated to Langmuir and Freundlich isotherm models. The best conditions for color and COD removal from textile effluent sample were obtained at lower values of pH. Total color removal was obtained with Mg-AlNO₃ and Ni-AlNO₃ LDHs. Reduction of COD to limits authorized by Moroccan standards was obtained with 0.5g/l LDHs dose.

Keywords: chemical oxygen demand, color removal, layered double hydroxides, textile wastewater treatment

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Authors: Satendra Pal Singh, Dalip Kr. Kakru, Jyoti Mishra, Rajesh Thakur, Tarana Sarwat

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COVID-19 is still an intrigue as far as morbidity or mortality is concerned. The rate of recovery varies from person to person, & it depends upon the accessibility of the healthcare system and the roles played by the physicians and caregivers. It is envisaged that with the passage of time, people would become immune to this virus, and those who are vulnerable would sustain themselves with the help of vaccines. The proposed study deals with the severeness of COVID-19 is associated with some specific biomarkers linked to correlate age and gender. We will be assessing the overall homeostasis of the persons who were affected by the coronavirus infection and also of those who recovered from it. Some people show more severe effects, while others show very mild symptoms, however, they show low CT values. Thus far, it is unclear why the new strain of Covid has different effects on different people in terms of age, gender, and ABO blood typing. According to data, the fatality rate with heart disease was 10.5 percent, 7.3 percent were diabetic, and 6 percent who are already infected from other comorbidities. However, some COVID-19 cases are worse than others & it is not fully explainable as of date. Overall data show that the ABO blood group is effective or prone to the risk of SARS-COV2 infection, while another study also shows the phenotypic effects of the blood group related to covid. It is an accepted fact that females have more strong immune systems than males, which may be related to the fact that females have two ‘X’ chromosomes, which might contain a more effective immunity booster gene on the X chromosome, and are capable to protect the female. Also specific sex hormones also induce a better immune response in a specific gender. This calls for in-depth analysis to be able to gain insight into this dilemma. COVID-19 is still not fully characterized, and thus we are not very familiar with its biology, mode of infection, susceptibility, and overall viral load in the human body. How many virus particles are needed to infect a person? How, then, comorbidity contribute to coronavirus infection? Since the emergence of this virus in 2020, a large number of papers have been published, and seemingly, vaccines have been prepared. But still, a large number of questions remain unanswered. The proneness of humans for infection by covid-19 needs to be established to be able to develop a better strategy to fight this virus. Our study will be on the Impact of demography on the Severity of covid-19 infection & at the same time, will look into gender-specific sensitivity of Covid-19 and the Operational variation of different biochemical markers in Covid-19 positive patients. Besides, we will be studying the co-relation, if any, of COVID severity & ABO Blood group type and the occurrence of the most common blood group type amongst positive patience.

Keywords: coronavirus, ABO blood group, age, gender

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Authors: Faraj M. Elkhatri, Hana Ali Alafi

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The spatial and temporal distribution of diagenetic alterations related impact on the reservoir quality of the Sarir Formation. (present-day burial depth of about 9000 feet) Depositional facies and diagenetic alterations are the main controls on reservoir quality of Sarir Formation Sirt Basin Libya; these based on lithology and grain size as well as authigenic clay mineral types and their distributions. However, petrology investigation obtained on study area with five sandstone wells concentrated on main rock components and the parameters that may have impacts on reservoirs. the main authigenic clay minerals are kaolinite and dickite, these investigations have confirmed by X.R.D analysis and clay fraction. mainly Kaolinite and Dickite were extensively presented on all of wells with high amounts. As well as trace of detrital smectite and less amounts of illitized mud-matrix are possibly found by SEM image. Thin layers of clay presented as clay-grain coatings in local depth interpreted as remains of dissolved clay matrix is partly transformed into kaolinite adjacent and towards pore throat. This also may have impacts on most of the pore throats of this sandstone which are open and relatively clean with some of fine martial have been formed on occluded pores. This material is identified by EDS analysis to be collections of not only kaolinite booklets but also small disaggregated kaolinite platelets derived from the disaggregation of larger kaolinite booklets. These patches of kaolinite not only fill this pore, but also coat some of the surrounding framework grains. Quartz grains often enlarged by authigenic quartz overgrowths partially occlude and reduce porosity. Scanning Electron Microscopy with Energy Dispersive Spectroscopy (SEM) was conducted on the post-test samples to examine any mud filtrate particles that may be in the pore throats. Semi-qualitative elemental data on selected minerals observed during the SEM study were obtained through the use of an Energy Dispersive Spectroscopy (EDS) unit. The samples showed mostly clean open pore throats, with limited occlusion by kaolinite. very fine-grained elemental combinations (Si/Al/Na/Cl, Si/Al Ca/Cl/Ti, and Qtz/Ti) have been identified and conformed by EDS analysis. However, the identification of the fine grained disaggregated material as mainly kaolinite though study area.

Keywords: fine migration, formation damage, kaolinite, soled bulging.

Procedia PDF Downloads 48

Authors: Farid Khosravikia, Patricia Clayton

Abstract:

The main objective of this work is to evaluate the advantages and disadvantages of various machine learning techniques in two key steps of seismic hazard and risk assessment of different types of structures. The first step is the development of ground-motion models, which are used for forecasting ground-motion intensity measures (IM) given source characteristics, source-to-site distance, and local site condition for future events. IMs such as peak ground acceleration and velocity (PGA and PGV, respectively) as well as 5% damped elastic pseudospectral accelerations at different periods (PSA), are indicators of the strength of shaking at the ground surface. Typically, linear regression-based models, with pre-defined equations and coefficients, are used in ground motion prediction. However, due to the restrictions of the linear regression methods, such models may not capture more complex nonlinear behaviors that exist in the data. Thus, this study comparatively investigates potential benefits from employing other machine learning techniques as statistical method in ground motion prediction such as Artificial Neural Network, Random Forest, and Support Vector Machine. The results indicate the algorithms satisfy some physically sound characteristics such as magnitude scaling distance dependency without requiring pre-defined equations or coefficients. Moreover, it is shown that, when sufficient data is available, all the alternative algorithms tend to provide more accurate estimates compared to the conventional linear regression-based method, and particularly, Random Forest outperforms the other algorithms. However, the conventional method is a better tool when limited data is available. Second, it is investigated how machine learning techniques could be beneficial for developing probabilistic seismic demand models (PSDMs), which provide the relationship between the structural demand responses (e.g., component deformations, accelerations, internal forces, etc.) and the ground motion IMs. In the risk framework, such models are used to develop fragility curves estimating exceeding probability of damage for pre-defined limit states, and therefore, control the reliability of the predictions in the risk assessment. In this study, machine learning algorithms like artificial neural network, random forest, and support vector machine are adopted and trained on the demand parameters to derive PSDMs for them. It is observed that such models can provide more accurate estimates of prediction in relatively shorter about of time compared to conventional methods. Moreover, they can be used for sensitivity analysis of fragility curves with respect to many modeling parameters without necessarily requiring more intense numerical response-history analysis.

Keywords: artificial neural network, machine learning, random forest, seismic risk analysis, seismic hazard analysis, support vector machine

Procedia PDF Downloads 83

Authors: Viviane P. Romani, Bradley D. Olsen, Vilásia G. Martins

Abstract:

Biodegradable films for food packaging have gained growing attention due to environmental pollution caused by synthetic films and the interest in the better use of resources from nature. Important research advances were made in the development of materials from proteins, polysaccharides, and lipids. However, the commercial use of these new generation of sustainable materials for food packaging is still limited due to their low mechanical and barrier properties that could compromise the food quality and safety. Thus, strategies to improve the performance of these materials have been tested, such as chemical modifications, incorporation of reinforcing structures and others. Cold plasma is a versatile, fast and environmentally friendly technology. It consists of a partially ionized gas containing free electrons, ions, and radicals and neutral particles able to react with polymers and start different reactions, leading to the polymer degradation, functionalization, etching and/or cross-linking. In the present study, biodegradable films from fish protein prepared through the casting technique were plasma treated using an AC glow discharge equipment. The reactor was preliminary evacuated to ~7 Pa and the films were exposed to air plasma for 2, 5 and 8 min. The films were evaluated by their mechanical and water vapor permeability (WVP) properties and changes in the protein structure were observed using Scanning Electron Microscopy (SEM) and X-ray diffraction (XRD). Potential cross-links and elimination of surface defects by etching might be the reason for the increase in tensile strength and decrease in the elongation at break observed. Among the times of plasma application tested, no differences were observed when higher times of exposure were used. The X-ray pattern showed a broad peak at 2θ = 19.51º that corresponds to the distance of 4.6Å by applying the Bragg’s law. This distance corresponds to the average backbone distance within the α-helix. Thus, the changes observed in the films might indicate that the helical configuration of fish protein was disturbed by plasma treatment. SEM images showed surface damage in the films with 5 and 8 min of plasma treatment, indicating that 2 min was the most adequate time of treatment. It was verified that plasma removes water from the films once weight loss of 4.45% was registered for films treated during 2 min. However, after 24 h in 50% of relative humidity, the water lost was recovered. WVP increased from 0.53 to 0.65 g.mm/h.m².kPa after plasma treatment during 2 min, that is desired for some foods applications which require water passage through the packaging. In general, the plasma technology affects the properties and structure of fish protein films. Since this technology changes the surface of polymers, these films might be used to develop multilayer materials, as well as to incorporate active substances in the surface to obtain active packaging.

Keywords: fish protein films, food packaging, improvement of properties, plasma treatment

Procedia PDF Downloads 142

Authors: Yunjia Yang, Peng Li, Gordon Xu, Timothy Mahony, Bing Zhang, Neena Mitter, Karishma Mody

Abstract:

Sheep flystrike is one of the most economically important diseases affecting the Australian sheep and wool industry (>356M/annually). Currently, control of Lucillia cuprina relies almost exclusively on chemicals controls, and the parasite has developed resistance to nearly all control chemicals used in the past. It is, therefore, critical to develop an alternative solution for the sustainable control and management of flystrike. RNA interference (RNAi) technologies have been successfully explored in multiple animal industries for developing parasites controls. This research project aims to develop a RNAi based biological control for sheep blowfly. Double-stranded RNA (dsRNA) has already proven successful against viruses, fungi, and insects. However, the environmental instability of dsRNA is a major bottleneck for successful RNAi. Bentonite polymer (BenPol) technology can overcome this problem, as it can be tuned for the controlled release of dsRNA in the gut challenging pH environment of the blowfly larvae, prolonging its exposure time to and uptake by target cells. To investigate the potential of BenPol technology for dsRNA delivery, four different BenPol carriers were tested for their dsRNA loading capabilities, and three of them were found to be capable of affording dsRNA stability under multiple temperatures (4°C, 22°C, 40°C, 55°C) in sheep serum. Based on stability results, dsRNA from potential targeted genes was loaded onto BenPol carriers and tested in larvae feeding assays, three genes resulting in knockdowns. Meanwhile, a primary blowfly embryo cell line (BFEC) derived from L. cuprina embryos was successfully established, aim for an effective insect cell model for testing RNAi efficacy for preliminary assessments and screening. The results of this study establish that the dsRNA is stable when loaded on BenPol particles, unlike naked dsRNA rapidly degraded in sheep serum. The stable nanoparticle delivery system offered by BenPol technology can protect and increase the inherent stability of dsRNA molecules at higher temperatures in a complex biological fluid like serum, providing promise for its future use in enhancing animal protection.

Keywords: lucilia cuprina, primary cell line establishment, RNA interference, insect cell transfection

Procedia PDF Downloads 52

Authors: Faraj M. Elkhatri

Abstract:

The spatial and temporal distribution of diagenetic alterations related impact on the reservoir quality of the Sarir Formation. ( present day burial depth of about 9000 feet) Depositional facies and diagenetic alterations are the main controls on reservoir quality of Sarir Formation Sirt Basin Libya; these based on lithology and grain size as well as authigenic clay mineral types and their distributions. However, petrology investigation obtained on study area with five sandstone wells concentrated on main rock components and the parameters that may have impacts on reservoirs. the main authigenic clay minerals are kaolinite and dickite, these investigations have confirmed by X.R.D analysis and clay fraction. mainly Kaolinite and Dickite were extensively presented on all of wells with high amounts. As well as trace of detrital smectite and less amounts of illitized mud-matrix are possibly find by SEM image. Thin layers of clay presented as clay-grain coatings in local depth interpreted as remains of dissolved clay matrix is partly transformed into kaolinite adjacent and towards pore throat. This also may have impacts on most of the pore throats of this sandstone which are open and relatively clean with some fine martial have been formed on occluded pores. This material is identified by EDS analysis to be collections of not only kaolinite booklets but also small disaggregated kaolinite platelets derived from the disaggregation of larger kaolinite booklets. These patches of kaolinite not only fill this pore but also coat some of the surrounding framework grains. Quartz grains often enlarged by authigenic quartz overgrowths partially occlude and reduce porosity. Scanning Electron Microscopy with Energy Dispersive Spectroscopy (SEM) was conducted on the post-test samples to examine any mud filtrate particles that may be in the pore throats. Semi-qualitative elemental data on selected minerals observed during the SEM study were obtained through the use of an Energy Dispersive Spectroscopy (EDS) unit. The samples showed mostly clean open pore throats with limited occlusion by kaolinite. very fine-grained elemental combinations (Si/Al/Na/Cl, Si/Al Ca/Cl/Ti, and Qtz/Ti) have been identified and conformed by EDS analysis. However, the identification of the fine grained disaggregated material as mainly kaolinite though study area.

Keywords: pore throat, fine migration, formation damage, solids plugging, porosity loss

Procedia PDF Downloads 127

Authors: A.D. Fredline, Beverly Stiles

Abstract:

This is a qualitative investigation that examines the social media site, Tumblr, for the goal of analyzing the controversy regarding the inclusion of asexuality in the LGBTQ+ community. As platforms such as Tumblr permit the development of communities for marginalized groups, social media serves as a core component to exclusionary practices and boundary negotiations for community membership. This research is important because there is a paucity of research on the topic and a significant gap in the literature with regards to intracommunity gatekeeping. However, discourse on the topic is blatantly apparent on social media platforms. The objectives are to begin to bridge the gap in the literature by examining attitudes towards the inclusion of asexuality within the LGBTQ+ community. In order to analyze the attitudes developed towards the inclusion of asexuality in the LGBTQ+ community, eight publicly available blogs on Tumblr.com were selected from both the “inclusionist” and “exclusionist” perspectives. Blogs selected were found through a basic search for “inclusionist” and “exclusionist” on the Tumblr website. Out of the first twenty blogs listed for each set of results, those centrally focused on asexuality discourse were selected. For each blog, the fifty most recent postings were collected. Analysis of the collected postings exposed three central themes from the exclusionist perspective as well as for the inclusionist perspective. Findings indicate that from the inclusionist perspective, asexuality belongs to the LGBTQ+ community. One primary argument from this perspective is that asexual individuals face opposition for their identity just as do other identities included in the community. This opposition is said to take a variety of forms, such as verbal shaming, assumption of illness and corrective rape. Another argument is that the LGBTQ+ community and asexuals face a common opponent in cisheterosexism as asexuals struggle with the assumed and expected sexualization. A final central theme is that denying asexual inclusion leads to the assumption of heteronormativity. Findings also indicate that from the exclusionist perspective, asexuality does not belong to the LGBTQ+ community. One central theme from this perspective is the equivalization of cisgender heteroromantic asexuals with cisgender heterosexuals. As straight individuals are not allowed in the community, exclusionists argue that asexuals engaged in opposite gender partnerships should not be included. Another debate is that including asexuality in the community sexualizes all other identities by assuming sexual orientation is inherently sexual rather than romantic. Finally, exclusionists also argue that asexuality encourages childhood labeling and forces sexual identities on children, something not promoted by the LGBTQ+ community. Conclusions drawn from analyzing both perspectives is that integration may be a possibility, but complexities add another layer of discourse. For example, both inclusionists and exclusionists agree that privileged identities do not belong to the LGBTQ+ community. The focus of discourse is whether or not asexuals are privileged. Clearly, both sides of the debate have the same vision of what binds the community together. The question that remains is who belongs to that community.

Keywords: asexuality, exclusionists, inclusionists, Tumblr

Procedia PDF Downloads 165

Authors: Stephen Osakue Amiandamhen, Schwaller Andreas, Martina Meincken, Luvuyo Tyhoda

Abstract:

Invasive alien tree species are currently being cleared in South Africa as a result of the forest and water imbalances. These species grow wildly constituting about 40% of total forest area. They compete with the ecosystem for natural resources and are considered as ecosystem engineers by rapidly changing disturbance regimes. As such, they are harvested for commercial uses but much of it is wasted because of their form and structure. The waste is being sold to local communities as fuel wood. These species can be considered as potential feedstock for the production of phosphate bonded composites. The presence of bark in wood-based composites leads to undesirable properties, and debarking as an option can be cost implicative. This study investigates the potentials of these invasive species processed without debarking on some fundamental properties of wood-based panels. Some invasive alien tree species were collected from EC Biomass, Port Elizabeth, South Africa. They include Acacia mearnsii (Black wattle), A. longifolia (Long-leaved wattle), A. cyclops (Red-eyed wattle), A. saligna (Golden-wreath wattle) and Eucalyptus globulus (Blue gum). The logs were chipped as received. The chips were hammer-milled and screened through a 1 mm sieve. The wood particles were conditioned and the quantity of bark in the wood was determined. The binding matrix was prepared using a reactive magnesia, phosphoric acid and class S fly ash. The materials were mixed and poured into a metallic mould. The composite within the mould was compressed at room temperature at a pressure of 200 KPa. After initial setting which took about 5 minutes, the composite board was demoulded and air-cured for 72 h. The cured product was thereafter conditioned at 20°C and 70% relative humidity for 48 h. Test of physical and strength properties were conducted on the composite boards. The effect of binder formulation and fly ash content on the properties of the boards was studied using fitted response surface technology, according to a central composite experimental design (CCD) at a fixed wood loading of 75% (w/w) of total inorganic contents. The results showed that phosphate/magnesia ratio of 3:1 and fly ash content of 10% was required to obtain a product of good properties and sufficient strength for intended applications. The proposed products can be used for ceilings, partitioning and insulating wall panels.

Keywords: invasive alien tree species, phosphate bonded composites, physical properties, strength

Procedia PDF Downloads 265

Authors: Dimitrios Bakavos, Dimitrios Tsivoulas, Chaowalit Limmaneevichitr

Abstract:

Aluminium cast alloys, of the Al-Si system, are widely used for shape castings. Their microstructures can be further improved on one hand, by alloying modification and on the other, by optimised artificial ageing. In this project four hypoeutectic Al-alloys, the A356, A356+ Ag, A356+Sc, and A356+Ag+Sc have been studied. The interactions of Ag and Sc during solidification and artificial ageing at 170°C to a T6 temper have been investigated in details. The evolution of the eutectic microstructure is studied by thermal analysis and interrupted solidification. The ageing kinetics of the alloys has been identified by hardness measurements. The precipitate phases, number density, and chemical composition has been analysed by means of transmission electron microscopy (TEM) and EDS analysis. Furthermore, the SHT effect onto the Si eutectic particles for the four alloys has been investigated by means of optical microscopy, image analysis, and the UTS strength has been compared with the UTS of the alloys after casting. The results suggest that the Ag additions, significantly enhance the ageing kinetics of the A356 alloy. The formation of β” precipitates were kinetically accelerated and an increase of 8% and 5% in peak hardness strength has been observed compared to the base A356 and A356-Sc alloy. The EDS analysis demonstrates that Ag is present on the β” precipitate composition. After prolonged ageing 100 hours at 170°C, the A356-Ag exhibits 17% higher hardness strength compared to the other three alloys. During solidification, Sc additions change the macroscopic eutectic growth mode to the propagation of a defined eutectic front from the mold walls opposite to the heat flux direction. In contrast, Ag has no significance effect on the solidification mode revealing a macroscopic eutectic growth similar to A356 base alloy. However, the mechanical strength of the as cast A356-Ag, A356-Sc, and A356+Ag+Sc additions has increased by 5, 30, and 35 MPa, respectively. The outcome is a tribute to the refining of the eutectic Si that takes place which it is strong in the A356-Sc alloy and more profound when silver and scandium has been combined. Moreover after SHT the Al alloy with the highest mechanical strength, is the one with Ag additions, in contrast to the as-cast condition where the Sc and Sc+Ag alloy was the strongest. The increase of strength is mainly attributed to the dissolution of grain boundary precipitates the increase of the solute content into the matrix, the spherodisation, and coarsening of the eutectic Si. Therefore, we could safely conclude for an A356 hypoeutectic alloy additions of: Ag exhibits a refining effect on the Si eutectic which is improved when is combined with Sc. In addition Ag enhance, the ageing kinetics increases the hardness and retains its strength at prolonged artificial ageing in a Al-7Si 0.3Mg hypoeutectic alloy. Finally the addition of Sc is beneficial due to the refinement of the α-Al grain and modification-refinement of the eutectic Si increasing the strength of the as-cast product.

Keywords: ageing, casting, mechanical strength, precipitates

Procedia PDF Downloads 477

Authors: Gabriela Kalcikova, Gregor Marolt, Anita Jemec Kokalj, Andreja Zgajnar Gotvajn

Abstract:

Since the 90’s, nanotechnology is one of the fastest growing fields of science. Nanomaterials are increasingly becoming part of many products and technologies. Metal oxide nanoparticles are among the most used nanomaterials. Zinc oxide nanoparticles (nZnO) is widely used due to its versatile properties; it has been used in products including plastics, paints, food, batteries, solar cells and cosmetic products. It is also a very effective photocatalyst used for water treatment. Such expanding application of nZnO increases their possible occurrence in the environment. In the aquatic ecosystem nZnO interact with natural environmental factors such as UV radiation, and thus it is essential to evaluate possible interaction between them. In this context, the aim of our study was to evaluate combined ecotoxicity of nZnO and Zn²⁺ on duckweed Lemna minor in presence or absence UV. Inhibition of vegetative growth of duckweed Lemna minor was monitored over a period of 7 days in multi-well plates. After the experiment, specific growth rate was determined. ZnO nanoparticles used were of primary size 13.6 ± 1.7 nm. The test was conducted with nominal nZnO and Zn²⁺ (in form of ZnCl₂) concentrations of 1, 10, 100 mg/L. Experiment was repeated with presence of natural intensity of UV (8h UV, 10 W/m² UVA, 0.5 W/m² UVB). Concentration of Zn during the test was determined by ICP-MS. In the regular experiment (absence of UV) the specific growth rate was slightly increased by low concentrations of nZnO and Zn²⁺ in comparison to control. However, 10 and 100 mg/L of Zn²⁺ resulted in 45% and 68% inhibition of the specific growth rate, respectively. In case of nZnO both concentrations (10 and 100 mg/L) resulted in similar ~ 30% inhibition and the response was not dose-dependent. The lack of the dose-response relationship is often observed in case of nanoparticles. The possible explanation is that the physical impact prevails instead of chemical ones. In the presence of UV the toxicity of Zn²⁺ was increased and 100 mg/L of Zn²⁺ caused total inhibition of the specific growth rate (100%). On the other hand, 100 mg/L of nZnO resulted in low inhibition (19%) in comparison to the experiment without UV (30%). It is thus expected, that tested nZnO is low photoactive, but could have a good UV absorption and/or reflective properties and thus protect duckweed against UV impacts. Measured concentration of Zn in the test suspension decreased only about 4% after 168h in the case of ZnCl₂. On the other hand concentration of Zn in nZnO test decreased by 80%. It is expected that nZnO were partially dissolved in the medium and at the same time agglomeration and sedimentation of particles took place and thus the concentration of Zn at the water level decreased. Results of our study indicated, that nZnO combined with UV of natural intensity does not increase toxicity of nZnO, but slightly protect the plant against UV negative effects. When Zn²⁺ and ZnO results are compared it seems that dissolved Zn plays a central role in the nZnO toxicity.

Keywords: duckweed, environmental factors, nanoparticles, toxicity

Procedia PDF Downloads 305

Authors: Joanna Cydejko, Paulina Mika

Abstract:

Hypersensitivity reactions are side effects of medications that resemble an allergic reaction. Anaphylaxis is a generalized, severe allergic reaction of the body caused by exposure to a specific agent at a dose tolerated by a healthy body. The most common causes of anaphylaxis are food (about 70%), Hymenoptera venoms (22%), and medications (7%), despite detailed diagnostics in 1% of people, the cause of the anaphylactic reaction was not indicated. Contrast media are anaphylactic agents of unknown mechanism. Hypersensitivity reactions can occur with both immunological and non-immunological mechanisms. Symptoms of anaphylaxis occur within a few seconds to several minutes after exposure to the allergen. Contrast agents are chemical compounds that make it possible to visualize or improve the visibility of anatomical structures. In the diagnosis of computed tomography, the preparations currently used are derivatives of the triiodide benzene ring. Pharmacokinetic and pharmacodynamic properties, i.e., their osmolality, viscosity, low chemotoxicity and high hydrophilicity, have an impact on better tolerance of the substance by the patient's body. In MRI diagnostics, macrocyclic gadolinium contrast agents are administered during examinations. The aim of this study is to present the results of the number and severity of anaphylactic reactions that occurred in patients in all age groups undergoing diagnostic imaging with intravenous administration of contrast agents. In non-ionic iodine CT and in macrocyclic gadolinium MRI. A retrospective assessment of the number of adverse reactions after contrast administration was carried out on the basis of data from the Department of Radiology of the University Clinical Center in Gdańsk, and it was assessed whether their different physicochemical properties had an impact on the incidence of acute complications. Adverse reactions are divided according to the severity of the patient's condition and the diagnostic method used in a given patient. Complications following the administration of a contrast medium in the form of acute anaphylaxis accounted for less than 0.5% of all diagnostic procedures performed with the use of a contrast agent. In the analysis period from January to December 2022, 34,053 CT scans and 15,279 MRI examinations with the use of contrast medium were performed. The total number of acute complications was 21, of which 17 were complications of iodine-based contrast agents and 5 of gadolinium preparations. The introduction of state-of-the-art contrast formulations was an important step toward improving the safety and tolerability of contrast agents used in imaging. Currently, contrast agents administered to patients are considered to be one of the best-tolerated preparations used in medicine. However, like any drug, they can be responsible for the occurrence of adverse reactions resulting from their toxic effects. The increase in the number of imaging tests performed with the use of contrast agents has a direct impact on the number of adverse events associated with their administration. However, despite the low risk of anaphylaxis, this risk should not be marginalized. The growing threat associated with the mass performance of radiological procedures with the use of contrast agents forces the knowledge of the rules of conduct in the event of symptoms of hypersensitivity to these preparations.

Keywords: anaphylactic, contrast medium, diagnostic, medical imagine

Procedia PDF Downloads 38

Authors: Min Koo Choi

Abstract:

The paper will examine Im Sun-dŭk’s two short stories, 'Iryoil' (Sunday, 1937) and 'Nazuoya' (A Godmother, 1942), which illuminate the subjects of Korean intellectuals going through the later period of a harsh and oppressive Japanese colonial rule. When Japan went to war against China in 1937, Korea, a colony of Japan since 1910, became an outpost for Japanese expansionism into China, and the Korean people were mobilized into the war effort. Nationalist movements and radical ideas that posed a threat and opposition to Japanese colonial rule in Korea and its colonial expansionism were ruthlessly suppressed, and Koreans were forcibly assimilated into becoming Japanese citizens without political rights. Racial discrimination between Koreans and Japanese was prevalent. Im Sun-dŭk, who participated in the Socialist movement in the 1930s, had his debut as a literary writer and a critic in the late 1930s, when Korean literary society was reincorporated in order to collaborate with the Japanese war effort through writing and public speech. Sun-duk's writing illuminates the unique internal landscape of a female subject who strives to live on while preserving her commitment and dignity under the circumstances that force Korean intellectuals either to collaborate with or acquiesce to Japanese colonial rule. 'Iryoil' (Sunday, 1937) foregrounds an educated intellectual, Hyeyŏng, who supplies her fiancé in prison for political involvement in resistance against Japan. On Sundays, she turns down her friends’ suggestion for enjoying holidays outside, due to her indebtedness to her fiancé. Her fiancé's imprisonment indicates the social conscience that still remains, and she seeks to share the commitment and suffering with her fiancé. The short story 'Nazuoya' (A Godmother, 1942), written in Japanese due to the suppression of Korean language publications at the time, also problematizes Japanese policy that forces Koreans to change their names into Japanese. Through the narrator I, who struggles to find a meaningful name for her cousin brother’s baby, she highlights how meaningful one’s name is for one’s life and identity. What makes her two stories unique is that her writing draws other people’s confessions into its own narrative through fragmentary forms, such as part of letter or reflection. The voices of others are intersected with the main character in 'Iryoil' (Sunday, 1937) and a narrator in 'Nazuoya' (A Godmother, 1942). In many ways, the narrator and main character provide the confessional voices who display the characters' gloomy interiorities. Even though these confessional voices do not share the commitment and values, both the main character and I in the stories reveal a more open set of viewpoints to them. In this way, they seek to form bonds and encouragement and acquire a more resilient sensibility that embraces those who strive to survive and endure in the gloomy days of the later period of Japanese colonial rule.

Keywords: Im Sun-dŭk, Japanese colonial rule, Korean literature, socialist movement

Procedia PDF Downloads 247

Authors: Louay Safi

Abstract:

The notion of secular society that evolved over the last two centuries was initially intended to free the public sphere from religious imposition, before it assumed the form a comprehensive ideology whose aim is to prevent any overt religious expression from the public space. The negative view of religious expression, and the desire by political elites to purge the public space from all forms of religious expressions were first experienced in the Middle East in the last decades of the twentieth century in relation to Islam, before it manifests itself in the twentieth century Europe. Arab regimes were encouraged by European democracies to marginalize all forms of religious expressions in the public as part of the secularization process that was deemed necessary for modernization and progress. The prohibition of Islamic symbols and outlawing the headscarf was first undertaken to Middle Eastern republics, such as Turkey in 1930s and Syria in 1970s, before it is implemented recently in France. Secularization has been perceived by European powers as the central aspect of social and political liberalization, and was given priority over democratization and human rights, so much so that European elites were willing to entrust the task of nurturing liberal democracy to Arab autocrats and dictators. Not only did the strategy of empowering autocratic regimes to effect liberal democratic culture failed, but it contributed to the rise of Islamist extremism and produced failed states in Syria and Iraq that undermine both national and global peace and stability. The paper adopts the distinction made by John Rawls between political and comprehensive liberalism to argue that the modernization via secularization in Muslim societies is counterproductive and has subverted early successful efforts at democratization and reform in the Middle East. Using case studies that illustrate the role of the secularization strategy in Syria, Iran, and Egypt in undermining democratic and reformist movements in those countries, the paper calls for adopting a different approach rooted in liberal and democratic values rather than cultural practices and lifestyle. The paper shows that Islamic values as articulated by reform movements support a democratic and pluralist political order, and emphasizes the need to legitimize and support social forces that advocate democracy and human rights. Such an alternative strategy allows for internal competition among social groups for popular support, and therefore enhances the chances that those with inclusive and forward-looking political principles and policies would create a democratic and pluralist political order more conducive to meaningful national and global cooperation, and respectful of human dignity.

Keywords: democracy, Islamic values, political liberalism, secularization

Procedia PDF Downloads 147

Authors: Belen Montero, Carmen Ramirez, Maite Rico, Rebeca Bouza, Irene Derungs

Abstract:

Starch is a promising polymer for producing biocomposite materials because it is renewable, completely biodegradable and easily available at a low cost. Thermoplastic starches (TPS) can be obtained after the disruption and plasticization of native starch with a plasticizer. In this work, the solvent casting method was used to obtain TPS films from wheat starch plasticized with glycerol and reinforced with nanocellulose (CNC). X-ray diffraction analysis was used to follow the evolution of the crystallinity. The native wheat starch granules have shown a profile corresponding to A-type crystal structures typical for cereal starches. When TPS films are analyzed a high amorphous halo centered on 19º is obtained, indicating the plasticization process is completed. SEM imaging was made in order to analyse the morphology. The image from the raw wheat starch granules shows a bimodal granule size distribution with some granules in large round disk-shape forms (A-type) and the others as smaller spherical particles (B-type). The image from the neat TPS surface shows a continuous surface. No starch aggregates or swollen granules can be seen so, the plasticization process is complete. In the surfaces of reinforced TPS films aggregates are seen as the CNC concentration in the matrix increases. The CNC influence on the mechanical properties of TPS films has been studied by dynamic mechanical analysis. A direct relation exists between the storage modulus values, E’, and the CNC content in reinforced TPS films: higher is the content of nanocellulose in the composite, higher is the value of E’. This reinforcement effect can be explained by the appearance of a strong and crystalline nanoparticle-TPS interphase. Thermal stability of films was analysed by TGA. It has not observed any influence on the behaviour related to the thermal degradation of films with the incorporation of the CNC. Finally, the resistance to the water absorption films was analysed following the standard UNE-EN ISO 1998:483. The percentage of water absorbed by the samples at each time was calculated. The addition of 5 wt % of CNC to the TPS matrix leads to a significant improvement in the moisture resistance of the starch based material decreasing their diffusivity. It has been associated to the formation of a nanocrystal network that prevents swelling of the starch and therefore water absorption and to the high crystallinity of cellulose compared to starch. As a conclusion, the wheat film reinforced with 5 wt % of cellulose nanocrystals seems to be a good alternative for short-life applications into the packaging industry, because of its greatest rigidity, thermal stability and moisture sorption resistance.

Keywords: biocomposites, nanocellulose, starch, wheat

Procedia PDF Downloads 188

Authors: Laura Canagueral-Pellice, Antonio Munar-Frau, Adaia Valls-Ontanon, Joao Carames, Federico Hernandez-Alfaro, Jordi Caballe-Serrano

Abstract:

Objective: Guided bone regeneration (GBR) aims to replace the missing bone with a new structure to achieve long-term stability of rehabilitations. The aim of the present systematic review and meta-analysis is to determine the effect of barrier membranes on histological outcomes after GBR procedures. Moreover, the effect of the grafting material and tissue gain were analyzed. Materials & methods: Two independent reviewers performed an electronic search in Pubmed and Scopus, identifying all eligible publications up to March 2020. Only randomized controlled trials (RCTs) assessing a histological analysis of augmented areas were included. Results: A total of 6 publications were included for the present systematic review. A total of 110 biopsied sites were analysed; 10 corresponded to vertical bone augmentation procedures, whereas 100 analysed horizontal regeneration procedures. A mean tissue gain of 3 ± 1.48mm was obtained for horizontal defects. Histological assessment of new bone formation, residual particle and sub-epithelial connective tissue (SCT) was reported. The four main barrier membranes used were natural collagen membranes, e-PTFE, polylactic resorbable membranes and acellular dermal matrix membranes (AMDG). The analysis demonstrated that resorbable membranes result in higher values of new bone formation and lower values of residual particles and SCT. Xenograft resulted in lower new bone formation compared to allograft; however, no statistically significant differences were observed regarding residual particle and SCT. Overall, regeneration procedures adding autogenous bone, plasma derivate or growth factors achieved in general greater new bone formation and tissue gain. Conclusions: There is limited evidence favoring the effect of a certain type of barrier membrane in GBR. Data needs to be evaluated carefully; however, resorbable membranes are correlated with greater new bone formation values, especially when combined with allograft materials and/or the addition of autogenous bone, platelet reach plasma (PRP) or growth factors in the regeneration area. More studies assessing the histological outcomes of different GBR protocols and procedures testing different biomaterials are needed to maximize the clinical and histological outcomes in bone regeneration science.

Keywords: barrier membrane, graft material, guided bone regeneration, implant surgery, histology

Procedia PDF Downloads 127

Authors: Peter Baji

Abstract:

In recent years, a growing body of literature emphasizes the increasingly negative impacts of urban road congestion in the everyday life of citizens. Although there are different responses from the public sector to decrease traffic congestion in urban regions, the most effective public intervention is using congestion charges. Because travel is an economic asset, its consumption can be controlled by extra taxes or prices effectively, but this demand-side intervention is often unpopular. Measuring traffic flows with the help of different methods has a long history in transport sciences, but until recently, there was not enough sufficient data for evaluating road traffic flow patterns on the scale of an entire road system of a larger urban area. European cities (e.g., London, Stockholm, Milan), in which congestion charges have already been introduced, designated a particular zone in their downtown for paying, but it protects only the users and inhabitants of the CBD (Central Business District) area. Through the use of Google Maps data as a resource for revealing urban road traffic flow patterns, this paper aims to provide a solution for a fairer and smarter congestion pricing method in cities. The case study area of the research contains three bordering districts of Budapest which are linked by one main road. The first district (5th) is the original downtown that is affected by the congestion charge plans of the city. The second district (13th) lies in the transition zone, and it has recently been transformed into a new CBD containing the biggest office zone in Budapest. The third district (4th) is a mainly residential type of area on the outskirts of the city. The raw data of the research was collected with the help of Google’s Distance Matrix API (Application Programming Interface) which provides future estimated traffic data via travel times between freely fixed coordinate pairs. From the difference of free flow and congested travel time data, the daily congestion patterns and hot spots are detectable in all measured roads within the area. The results suggest that the distribution of congestion peak times and hot spots are uneven in the examined area; however, there are frequently congested areas which lie outside the downtown and their inhabitants also need some protection. The conclusion of this case study is that cities can develop a real-time and place-based congestion charge system that forces car users to avoid frequently congested roads by changing their routes or travel modes. This would be a fairer solution for decreasing the negative environmental effects of the urban road transportation instead of protecting a very limited downtown area.

Keywords: Budapest, congestion charge, distance matrix API, application programming interface, pilot study

Procedia PDF Downloads 173

Authors: Sevdenur Onger, Ali Asram Sagiroglu

Abstract:

Hyperpigmentation is a cosmetically unappealing skin problem caused by an overabundance of melanin in the skin. Its pathophysiology is caused by melanocytes being exposed to paracrine melanogenic stimuli, which can upregulate melanogenesis-related enzymes (such as tyrosinase) and cause melanosome formation. Tyrosinase is linked to the development of melanosomes biochemically, and it is the main target of hyperpigmentation treatment. therefore, decreasing tyrosinase activity to reduce melanosomes has become the main target of hyperpigmentation treatment. Niacinamide (NA) is a natural chemical found in a variety of plants that is used as a skin-whitening ingredient in cosmetic formulations. NA decreases melanogenesis in the skin by inhibiting melanosome transfer from melanocytes to covering keratinocytes. Furthermore, NA protects the skin from reactive oxygen species and acts as a main barrier with the skin, reducing moisture loss by increasing ceramide and fatty acid synthesis. However, it is very difficult for hydrophilic compounds such as NA to penetrate deep into the skin. Furthermore, because of the nicotinic acid in NA, it is an irritant. As a result, we've concentrated on strategies to increase NA skin permeability while avoiding its irritating impacts. Since nanotechnology can affect drug penetration behavior by controlling the release and increasing the period of permanence on the skin, it can be a useful technique in the development of whitening formulations. Liposomes have become increasingly popular in the cosmetics industry in recent years due to benefits such as their lack of toxicity, high penetration ability in living skin layers, ability to increase skin moisture by forming a thin layer on the skin surface, and suitability for large-scale production. Therefore, liposomes containing NA were developed for this study. Different formulations were prepared by varying the amount of phospholipid and cholesterol and examined in terms of particle sizes, polydispersity index (PDI) and pH values. The pH values of the produced formulations were determined to be suitable with the pH value of the skin. Particle sizes were determined to be smaller than 250 nm and the particles were found to be of homogeneous size in the formulation (pdi<0.30). Despite the important advantages of liposomal systems, they have low viscosity and stability for topical use. For these reasons, in this study, liposomal cream formulations have been prepared for easy topical application of liposomal systems. As a result, liposomal cream formulations containing NA have been successfully prepared and characterized. Following the in-vitro release and ex-vivo diffusion studies to be conducted in the continuation of the study, it is planned to test the formulation that gives the most appropriate result on the volunteers after obtaining the approval of the ethics committee.

Keywords: delivery systems, hyperpigmentation, liposome, niacinamide

Procedia PDF Downloads 95