Search results for: active optical cable(AOC)
1320 Bilingual Siblings and Dynamic Family Language Policies in Italian/English Families
Authors: Daniela Panico
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Framed by language socialization and family language policy theories, the present study explores the ways the language choice patterns of bilingual siblings contribute to the shaping of the language environment and the language practices of Italian/English families residing in Sydney. The main source of data is video recordings of naturally occurring parent-children and child-to-child interactions during everyday routines (i.e., family mealtimes and siblings playtime) in the home environment. Recurrent interactional practices are analyzed in detail through a conversational analytical approach. This presentation focuses on the interactional trajectories developing during the negotiation of language choices between all family members and between siblings in face-to-face interactions. Fine-grained analysis is performed on language negotiation sequences of multiparty bilingual conversations in order to uncover the sequential patterns through which a) the children respond to the parental strategies aiming to minority language maintenance, and b) the siblings influence each other’s language use and choice (e.g., older siblings positioning themselves as language teachers and language brokers, younger siblings accepting the role of apprentices). The findings show that, along with the parents, children are active socializing agents in the family and, with their linguistic behavior, they contribute to the establishment of a bilingual or a monolingual context in the home. Moreover, by orienting themselves towards the use of one or the other language in family talk, bilingual siblings are a major internal micro force in the language ecology of a bilingual family and can strongly support language maintenance or language shift processes in such domain. Overall, the study provides insights into the dynamic ways in which family language policy is interactionally negotiated and instantiated in bilingual homes as well as the challenges of intergenerational language transmission.Keywords: bilingual siblings, family interactions, family language policy, language maintenance
Procedia PDF Downloads 1911319 Inhibitory Activity of Podospermum canum and Its Active Components on Collagenase, Elastase and Hyaluronidase Enzymes
Authors: Ozlem Bahadir Acikara, Mert Ilhan, Ekin Kurtul, Karel Smejkal, Esra Kupeli Akkol
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Present study is aimed to investigate in vitro inhibitory effects of the extracts prepared from the aerial parts of Podospermum canum (Asteraceae) on hyaluronidase, collagenase, and elastase enzymes using a bioassay-guided fractionation. Inhibitory effects of the extract, sub-extracts, fractions obtained by column chromatography, and isolated compounds on collagenase, elastase, and hyaluronidase were performed by using in vitro enzyme inhibitory assays based on spectrophotometric evaluation. The ethyl acetate and remaining water extracts prepared from the plant displayed significant inhibitory activities on collagenase and elastase, while petroleum ether and chloroform extracts did not show any inhibitory activity. Eleven known compounds: arbutin, 6'-O-caffeoylarbutin, cichoriin, 3,5-dicaffeoylquinic acid methyl ester, apigenin-7-O-β-glucoside, luteolin-7-O-β-glucoside, apigenin-7-O-β-rutinoside, isoorientin, orientin, vitexin, procatechuic acid, and compound 4-hydroxy-benzoic acid 4-(6-O-α-rhamnopyranosyl-β-glucopyranosyl) benzyl ester have been obtained from ethyl acetate sub-extract of the plant through bioassay-guided fractionation and isolation. Results of the present study have revealed that among the isolated compounds, apigenin-7-O-β-glucoside, luteolin-7-O-β-glucoside, apigenin-7-O-β-rutinoside and isoorientin showed potent enzyme inhibitory activities. However, methanolic extract of P. canum displayed a greater inhibitory activity than fractions and isolated compounds both on collagenase and elastase.Keywords: Asteraceae, collagenase, elastase, hyaluronidase, Podospermum canum
Procedia PDF Downloads 1311318 Analysis of Metamaterial Permeability on the Performance of Loosely Coupled Coils
Authors: Icaro V. Soares, Guilherme L. F. Brandao, Ursula D. C. Resende, Glaucio L. Siqueira
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Electrical energy can be wirelessly transmitted through resonant coupled coils that operate in the near-field region. Once in this region, the field has evanescent character, the efficiency of Resonant Wireless Power Transfer (RWPT) systems decreases proportionally with the inverse cube of distance between the transmitter and receiver coils. The commercially available RWPT systems are restricted to short and mid-range applications in which the distance between coils is lesser or equal to the coil size. An alternative to overcome this limitation is applying metamaterial structures to enhance the coupling between coils, thus reducing the field decay along the distance between them. Metamaterials can be conceived as composite materials with periodic or non-periodic structure whose unconventional electromagnetic behaviour is due to its unit cell disposition and chemical composition. This new kind of material has been used in frequency selective surfaces, invisibility cloaks, leaky-wave antennas, among other applications. However, for RWPT it is mainly applied as superlenses which are lenses that can overcome the optical limitation and are made of left-handed media, that is, a medium with negative magnetic permeability and electric permittivity. As RWPT systems usually operate at wavelengths of hundreds of meters, the metamaterial unit cell size is much smaller than the wavelength. In this case, electric and magnetic field are decoupled, therefore the double negative condition for superlenses are not required and the negative magnetic permeability is enough to produce an artificial magnetic medium. In this work, the influence of the magnetic permeability of a metamaterial slab inserted between two loosely coupled coils is studied in order to find the condition that leads to the maximum transmission efficiency. The metamaterial used is formed by a subwavelength unit cell that consist of a capacitor-loaded split ring with an inner spiral that is designed and optimized using the software Computer Simulation Technology. The unit cell permeability is experimentally characterized by the ratio of the transmission parameters between coils measured with and without the presence of the metamaterial slab. Early measurements results show that the transmission coefficient at the resonant frequency after the inclusion of the metamaterial is about three times higher than with just the two coils, which confirms the enhancement that this structure brings to RWPT systems.Keywords: electromagnetic lens, loosely coupled coils, magnetic permeability, metamaterials, resonant wireless power transfer, subwavelength unit cells
Procedia PDF Downloads 1461317 Application of Non-Smoking Areas in Hospitals
Authors: Nur Inayah Ismaniar, Sukri Palutturi, Ansariadi, Atjo Wahyu
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Background: In various countries in the world, the problem of smoking is now considered something serious because of the effects of smoking which can not only lead to addiction but also have the potential to harm health. Public health authorities have concluded that one solution that can be done to protect the public from active smokers is to issue a policy that requires public facilities to be completely smoke-free. The hospital is one of the public facilities that has been designated as a smoke-free area. However, the implementation and maintenance of a successful program based on a smoke-free hospital are still considered an ongoing challenge worldwide due to the very low level of adherence. The low level of compliance with this smoke-free policy is also seen in other public facilities. The purpose of the literature review is to review the level of compliance with the application of the Non-Smoking Area policy, how this policy has succeeded in reducing smoking activity in hospitals, and what factors lead to such compliance in each country in the world. Methods: A literature review of articles was carried out on all types of research methods, both qualitative and quantitative. The sample is all subjects who are in the research location, which includes patients, staff and hospital visitors. Results: Various variations in the level of compliance were found in various kinds of literature. The literature with the highest level of compliance is 88.4%. Furthermore, several determinants that are known to affect the compliance of the Non-Smoking Area policies in hospitals include communication, information, knowledge, perceptions, interventions, attitudes and support. Obstacles to its enforcement are the absence of sanctions against violators of the Non-Smoking Area policy, the ineffectiveness of the function of policymakers in hospitals, and negative perceptions of smoking related to mental health. Conclusion: Violations of the Non-Smoking Area policy are often committed by the hospital staff themselves, which makes it difficult for this policy to be fully enforced at various points in the hospital.Keywords: health policy, non-smoking area, hospital, implementation
Procedia PDF Downloads 891316 Physical and Microbiological Evaluation of Chitosan Films: Effect of Essential Oils and Storage
Authors: N. Valderrama, W. Albarracín, N. Algecira
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It was studied the effect of the inclusion of thyme and rosemary essential oils into chitosan films, as well as the microbiological and physical properties when storing chitosan film with and without the mentioned inclusion. The film forming solution was prepared by dissolving chitosan (2%, w/v), polysorbate 80 (4% w/w CH) and glycerol (16% w/w CH) in aqueous lactic acid solutions (control). The thyme (TEO) and rosemary (REO) essential oils (EOs) were included 1:1 w/w (EOs:CH) on their combination 50/50 (TEO:REO). The films were stored at temperatures of 5, 20, 33°C and a relative humidity of 75% during four weeks. The films with essential oil inclusion did not show an antimicrobial activity against strains. This behavior could be explained because the chitosan only inhibits the growth of microorganisms in direct contact with the active sites. However, the inhibition capacity of TEO was higher than the REO and a synergic effect between TEO:REO was found for S. enteritidis strains in the chitosan solution. Some physical properties were modified by the inclusion of essential oils. The addition of essential oils does not affect the mechanical properties (tensile strength, elongation at break, puncture deformation), the water solubility, the swelling index nor the DSC behavior. However, the essential oil inclusion can significantly decrease the thickness, the moisture content, and the L* value of films whereas the b* value increased due to molecular interactions between the polymeric matrix, the loosing of the structure, and the chemical modifications. On the other hand, the temperature and time of storage changed some physical properties on the chitosan films. This could have occurred because of chemical changes, such as swelling in the presence of high humidity air and the reacetylation of amino groups. In the majority of cases, properties such as moisture content, tensile strength, elongation at break, puncture deformation, a*, b*, chrome, ΔE increased whereas water resistance, swelling index, L*, and hue angle decreased.Keywords: chitosan, food additives, modified films, polymers
Procedia PDF Downloads 3661315 The Methanotrophic Activity in a Landfill Bio-Cover through a Subzero Winter
Authors: Parvin Berenjkar, Qiuyan Yuan, Richard Sparling, Stan Lozecznik
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Landfills highly contribute to anthropological global warming through CH₄ emissions. Landfills are usually capped by a conventional soil cover to control the migration of gases. Methane is consumed by CH₄-oxidizing microorganisms known as methanotrophs that naturally exist in the landfill soil cover. The growth of methanotrophs can be optimized in a bio-cover that typically consists of a gas distribution layer (GDL) to homogenize landfill gas fluxes and an overlying oxidation layer composed of suitable materials that support methanotrophic populations. Materials such as mature yard waste composts can provide an inexpensive and favourable porous support for the growth and activity of methanotrophs. In areas with seasonal cold climates, it is valuable to know if methanotrophs in a bio-cover can survive in winter until the next spring, and how deep they are active in the bio-cover to mitigate CH₄. In this study, a pilot bio-cover was constructed in a closed landfill cell in Winnipeg that has a very cold climate in Canada. The bio-cover has a surface area of 2.5 m x 3.5 m and 1.5 m of depth, filled with 50 cm of gravel as a GDL and 70 cm of biosolids compost amended with yard and leaf waste compost. The observed in situ potential of methanotrophs for CH₄ oxidation was investigated at a specific period of time from December 2016 to April 2017 as well as November 2017 to April 2018, when the transition to surface frost and thawing happens in the bio-cover. Compost samples taken from different depths of the bio-cover were incubated in the laboratory under standardized conditions; an optimal air: methane atmosphere, at 22ºC, but at in situ moisture content. Results showed that the methanotrophs were alive oxidizing methane without a lag, indicating that there was the potential for methanotrophic activity at some depths of the bio-cover.Keywords: bio-cover, global warming, landfill, methanotrophic activity
Procedia PDF Downloads 1211314 Perceptions of Research Staff on the Implementation of Each-B Study: A Randomised Controlled Trial
Authors: Laila Khawaja
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In recent years, an increasing emphasis has been placed on measuring program implementation, in part because of the great variability in how complex interventions are delivered in real-life settings. There is an increased awareness that while conducting process evaluations, one should aim to identify and understand the complexities of intervention if they are to be used for future intervention development or the strategies needed to implement the same intervention in a different setting. Complex interventions are public health interventions that are not drugs or surgical procedures but have many potential active aspects of intervention. In this paper, process evaluations are aligned with MRC guidelines to identify contextual factors related to outcomes to assess the quality of implementation. This paper briefly discusses the perceptions of research team on the implementation of the intervention of ‘Engaging Adolescents in Changing Behaviour’ (EACH-B), a school-based complex intervention study aiming to improve diet and physical activity among adolescents aged 12-13 years. Through qualitative interviews and focus groups with 10 staff members, we aimed to understand their experiences and reflections on implementing the EACH-B trial delivered in 49 Schools around Hampshire, England. Data were uploaded into NVivo, and analysis was conducted using thematic analysis. The investigation revealed two overarching themes: (a) how the communication patterns with teachers were impacted during the delivery of implementation and (b) what were the team’s strategies to keep logistics aligned with the research process that impacted the overall implementation of the trial. The paper informs adaptation strategies used by the research team to establish and maintain effective communication with the teachers as well as the thoughtfulness of the team’s logistic strategy for the successful delivery of the trial.Keywords: complex interventions, process evaluation, adaptation strategies, randomised controlled trial
Procedia PDF Downloads 661313 Women as Victims of Land Grabbing: Implications for Household Food Security and Livelihoods in Cameroon
Authors: Valentine Ndi
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This multi-sited research will make use of primary and secondary data to understand the multiple implications of land grabbing for local food production and rural livelihoods in Cameroon. Amidst restricted access to land and forest resources, this study will demonstrate how land previously accessed by communities to grow crops and to harvest forest resources is being acquired and transformed into commercial oil palm plantations by Herakles Farms, a US-based company, with Sithe Global Sustainable Oils Cameroon as its local subsidiary. Focusing on selected land grabbing communities in Cameroon, the study uses a feminist political ecology lens to examine the gendered nature in resources access and its impacts for women’s food production in particular, and rural livelihoods in general. The paper will argue that the change in land use particularly erodes women’s rights to access land and forest resources, and in turn negatively affects local food production and rural livelihood in the region. It will show how women in the region play instrumental and dominant roles in ensuring local food production through subsistence and semi-subsistence agriculture but are unfortunately the main losers of territory that the state considers as ‘empty’ or underutilized - and is subjected to appropriation. The paper will conclude that, rural women’s active participation in the decision-making processes concerning the use of and/or allotment of land to foreign investors is indispensable to guarantee local, national and global food security, but also to ensure that alternative livelihood options are provided, particularly to those rural women facing dispossession or at risk of being dispossessed.Keywords: land grabbing, feminst political ecology, gender, access to resources, rural livelihoods, Cameroon
Procedia PDF Downloads 2661312 Resilience and Mindfulness as Individual Resources Building Communication Skills for Physicians
Authors: Malgorzata Sekulowicz, Krystyna Boron-Krupinska, Paulina Morga, Blazej Cieslik
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Burnout is highly prevalent in health care employees, especially in physicians. It significantly reduces the efficiency of these employees, which can have negative consequences for both physicians and patients. Resilience and mindfulness enhancing positive emotions, leading to sustainable development and personal commitment, can have a significant impact on burnout. Therefore, the aim of this study was to determine the relationship between burnout symptoms and mindfulness and resilience among physicians. The authors conducted a cross-sectional survey study among seventy-four polish physicians. Participants filled out the following psychometric tools: the Maslach Burnout Inventory - Human Services Survey (MBI-HSS), Five Facet Mindfulness Questionnaire (FFMQ), Areas of Work-Life Survey (AWS), International Personality Item Pool (IPIP), the Resilience Assessment Scale (SPP-25) and the Mini-COPE Inventory. The relationship between burnout and resilience and mindfulness was assessed with path analysis. Analyzing the relationship between MBI-HSS components and mindfulness, a significant negative correlation of the FFMQ score with emotional exhaustion (-0.50, p < 0.05) and depersonalization (-0.43, p < 0.05) and a positive correlation with personal accomplishment (0.50, p < 0.05) was demonstrated. Analyzing resilience, a statistically significant relationship of SPP-25 with all tested components of MBI-HSS was demonstrated: emotional exhaustion (-0.54, p < 0.05), depersonalization (-0.31, p < 0.05) and personal accomplishment (0.35, p < 0.05). In the group of medical doctors, the higher the level of mindfulness and resilience, the lower the risk of burnout. Furthermore, the more frequently used active coping strategies (planning, acceptance), the lower the risk of burnout, while the use of passive, evasive strategies increases the risk of burnout. It may be worth considering implementing mindfulness intervention to effectively manage burnout symptoms in this group.Keywords: burnout, medical doctors, mindfulness, physicians, resilience
Procedia PDF Downloads 1051311 Design and Validation of an Aerodynamic Model of the Cessna Citation X Horizontal Stabilizer Using both OpenVSP and Digital Datcom
Authors: Marine Segui, Matthieu Mantilla, Ruxandra Mihaela Botez
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This research is the part of a major project at the Research Laboratory in Active Controls, Avionics and Aeroservoelasticity (LARCASE) aiming to improve a Cessna Citation X aircraft cruise performance with an application of the morphing wing technology on its horizontal tail. However, the horizontal stabilizer of the Cessna Citation X turns around its span axis with an angle between -8 and 2 degrees. Within this range, the horizontal stabilizer generates certainly some unwanted drag. To cancel this drag, the LARCASE proposes to trim the aircraft with a horizontal stabilizer equipped by a morphing wing technology. This technology aims to optimize aerodynamic performances by changing the conventional horizontal tail shape during the flight. As a consequence, this technology will be able to generate enough lift on the horizontal tail to balance the aircraft without an unwanted drag generation. To conduct this project, an accurate aerodynamic model of the horizontal tail is firstly required. This aerodynamic model will finally allow precise comparison between a conventional horizontal tail and a morphed horizontal tail results. This paper presents how this aerodynamic model was designed. In this way, it shows how the 2D geometry of the horizontal tail was collected and how the unknown airfoil’s shape of the horizontal tail has been recovered. Finally, the complete horizontal tail airfoil shape was found and a comparison between aerodynamic polar of the real horizontal tail and the horizontal tail found in this paper shows a maximum difference of 0.04 on the lift or the drag coefficient which is very good. Aerodynamic polar data of the aircraft horizontal tail are obtained from the CAE Inc. level D research aircraft flight simulator of the Cessna Citation X.Keywords: aerodynamic, Cessna, citation, coefficient, Datcom, drag, lift, longitudinal, model, OpenVSP
Procedia PDF Downloads 3731310 Investigate the Rural Mobility and Accessibility Challenges of Seniors
Authors: Tom Ryan
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This paper investigates the rural mobility and accessibility challenges of a specific target group - Seniors. The target group is those over 66 years of age who are entitled to use the Public Transport (PT) Free Travel Scheme in rural Ireland. The paper explores at a high level some of the projected rural PT challenges and requirements over the next 10-15 years, noting that statistical predictions show that there will be a significant population demographic shift within the Senior's age profile. Using the PESTEL framework, the literature review explored existing research concerning mobility, accessibility challenges, and the opportunities Seniors face. Twenty-seven qualitative in-depth interviews with stakeholders within the ecosystem were undertaken. The stakeholders included: rural PT customers, Local-Link managers, NTA senior management, a Minister of State, and a European parliament policymaker. Tier 1 interviewee feedback spotlights that the PT network system does not exist for rural patients to access hospital facilities. There was no evidence from the Tier 2 research findings to show that health policymakers and transport planners are working to deliver a national solution to support patients getting access to hospital appointments. Several research interviewees discussed the theme of isolation and the perceived stigma of senior males utilising PT. The findings indicated that MaaS is potentially revolutionary in the PT arena. Finally, this paper suggests several short-, medium- and long-term recommendations based on the research findings. These recommendations are a potential springboard to ensure that rural PT is suitable for future Irish generations.Keywords: accessibility, active ageing, car dependence, isolation, seniors health issues, behavioural changes, environmental challenges, internet of things, demand responsive, mobility as a service
Procedia PDF Downloads 1091309 Competing Discourses of Masculinity and Seeking Mental Health Assistance among Male Police Officers in Canada
Authors: Maria T. Cruz, Scott N. Thompson
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In recent years, Canadian federal and provincial law enforcement organizations have implemented numerous mental health strategies in an attempt to address officers’ mental health and wellness needs. Despite these reforms, however, mental illness continues to persist in these populations. Whereas workplace stressors continue to be factored into the development of mental health initiatives, it is proposed that aspects of masculine culture have been overlooked as contributing to the prevalence of mental illness among Canadian officers. By drawing on Michel Foucault’s theory of discourse, this study was conducted to determine if elements of masculine discourse exist as a socio-cultural barrier for officers seeking mental health assistance. This research supported the above hypothesis, and furthermore, identified how masculine discourse works in competition with mental health-related help-seeking discourses. To answer the research question, semi-structured phone interviews with active and retired male officers from Western provincial and municipal policing organizations, and the Royal Canadian Mounted Police were employed. Through thematic analysis of the transcripts, the data revealed three themes: i) masculinity in law enforcement is a determinant of workplace competency; ii) the dominance of masculine culture in law enforcement is problematic for mental health, and iii) improved help-seeking policies complicate how masculinity is expressed in law enforcement organizations. These findings suggest that within the reviewed Canadian law enforcement organizations, aspects of masculinity act as a socio-cultural barrier to officers seeking mental health services, and that the two conflicting discourses of masculinity and mental health-related help-seeking appear to be in competition with each other.Keywords: competing discourses, dominant discourses, Foucault’s theory of discourse, law enforcement, masculinity, mental health, police officers
Procedia PDF Downloads 1791308 Fused Deposition Modelling as the Manufacturing Method of Fully Bio-Based Water Purification Filters
Authors: Natalia Fijol, Aji P. Mathew
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We present the processing and characterisation of three-dimensional (3D) monolith filters based on polylactic acid (PLA) reinforced with various nature-derived nanospecies such as hydroxyapatite, modified cellulose fibers and chitin fibers. The nanospecies of choice were dispersed in PLA through Thermally Induced Phase Separation (TIPS) method. The biocomposites were developed via solvent-assisted blending and the obtained pellets were further single-screw extruded into 3D-printing filaments and processed into various geometries using Fused Deposition Modelling (FDM) technique. The printed prototypes included cubic, cylindrical and hour-glass shapes with diverse patterns of printing infill as well as varying pore structure including uniform and multiple level gradual pore structure. The pores and channel structure as well as overall shape of the prototypes were designed in attempt to optimize the flux and maximize the adsorption-active time. FDM is a cost and energy-efficient method, which does not require expensive tools and elaborated post-processing maintenance. Therefore, FDM offers the possibility to produce customized, highly functional water purification filters with tuned porous structures suitable for removal of wide range of common water pollutants. Moreover, as 3D printing becomes more and more available worldwide, it allows producing portable filters at the place and time where they are most needed. The study demonstrates preparation route for the PLA-based, fully biobased composite and their processing via FDM technique into water purification filters, addressing water treatment challenges on an industrial scale.Keywords: fused deposition modelling, water treatment, biomaterials, 3D printing, nanocellulose, nanochitin, polylactic acid
Procedia PDF Downloads 1151307 Emotion Detection in Twitter Messages Using Combination of Long Short-Term Memory and Convolutional Deep Neural Networks
Authors: Bahareh Golchin, Nooshin Riahi
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One of the most significant issues as attended a lot in recent years is that of recognizing the sentiments and emotions in social media texts. The analysis of sentiments and emotions is intended to recognize the conceptual information such as the opinions, feelings, attitudes and emotions of people towards the products, services, organizations, people, topics, events and features in the written text. These indicate the greatness of the problem space. In the real world, businesses and organizations are always looking for tools to gather ideas, emotions, and directions of people about their products, services, or events related to their own. This article uses the Twitter social network, one of the most popular social networks with about 420 million active users, to extract data. Using this social network, users can share their information and opinions about personal issues, policies, products, events, etc. It can be used with appropriate classification of emotional states due to the availability of its data. In this study, supervised learning and deep neural network algorithms are used to classify the emotional states of Twitter users. The use of deep learning methods to increase the learning capacity of the model is an advantage due to the large amount of available data. Tweets collected on various topics are classified into four classes using a combination of two Bidirectional Long Short Term Memory network and a Convolutional network. The results obtained from this study with an average accuracy of 93%, show good results extracted from the proposed framework and improved accuracy compared to previous work.Keywords: emotion classification, sentiment analysis, social networks, deep neural networks
Procedia PDF Downloads 1371306 Antibacterial Activity and Kinetic Parameters of the Essential Oils of Drypetes Gossweileri S.Moore, Ocimun Gratissimum L. and Cymbopogon Citratus DC Stapf on 5 Multidrug-Resistant Strains of Shigella
Authors: Elsa Makue Nguuffo, Esther Del Florence Moni Ndedi, Jacky Njiki Bikoï, Jean Paul Assam Assam, Maximilienne Ascension Nyegue
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Aims: The present study aims to evaluate the kinetic parameters of essential oils (EOs) and combinations fromDrypetes gossweileri Stem Bark, Ocimum gratissimum leaves, Cymbopogon citratusleaves after evaluation of their antibacterial activityonmultidrug-resistant strains ofShigella. Material and Methods:fiveclinical strains of Shigellaisolated from patients with diarrhoeaincluding Shigella flexneri, and 4 otherstrains of Shigella sppwere selected. Their antibiotic profile was established using agar test diffusion with seven antibiotics belonging to seven classes.EOs were extracted from each plant using hydrodistillation process. The activity of Ciprofloxacin®, OEs, and their combination formulatedinthe followingratios(w/w/w): C1: 1/1/1; C2: 2/1/1; C3: 1/2/1, C4:1/1/2 was evaluated microdilution assay. The various interactions of OEs in the different combinations were determined then the OE and the most active combination were retained to determine their kinetic parameters on S. flexneri. Results: Antibiotic susceptibility tests revealed that most Shigella isolates (n = 4) were resistant to six antibiotics tested. Ciprofloxacin (40%), Nalidixic acid (60%), Tetracycline (80%), Amoxicillin (100%), Cefotaxime (80%), Erythromycin (100%), and Cotrimoxazole (80%) were the profiles found in the different strains of Shigella. About the antibacterial activity of OEs, Drypetes gossweileriOE and C2 combination had shown a higher Shigellicide property with a Minimal Inhibitory Concentration(MIC) respectivelyranging from 0.078 mg/mL to 0.312 mg/mL and 0.012 to 1.562 mg/mL. Combinations of OEs showed various interactions whose synergistic effects were mostly encountered. The best deactivation was obtained by the combination C2 at 16 MIC withb= 1.962. Conclusion: the susceptibility of Shigella to OEs and their combinations justifies their use in traditional medicine in the treatment of shigellosis.Keywords: shigella, multidrug-resistant, EOs, kinetic
Procedia PDF Downloads 981305 Power Energy Management For A Grid-Connected PV System Using Rule-Base Fuzzy Logic
Authors: Nousheen Hashmi, Shoab Ahmad Khan
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Active collaboration among the green energy sources and the load demand leads to serious issues related to power quality and stability. The growing number of green energy resources and Distributed-Generators need newer strategies to be incorporated for their operations to keep the power energy stability among green energy resources and micro-grid/Utility Grid. This paper presents a novel technique for energy power management in Grid-Connected Photovoltaic with energy storage system under set of constraints including weather conditions, Load Shedding Hours, Peak pricing Hours by using rule-based fuzzy smart grid controller to schedule power coming from multiple Power sources (photovoltaic, grid, battery) under the above set of constraints. The technique fuzzifies all the inputs and establishes fuzzify rule set from fuzzy outputs before defuzzification. Simulations are run for 24 hours period and rule base power scheduler is developed. The proposed fuzzy controller control strategy is able to sense the continuous fluctuations in Photovoltaic power generation, Load Demands, Grid (load Shedding patterns) and Battery State of Charge in order to make correct and quick decisions.The suggested Fuzzy Rule-based scheduler can operate well with vague inputs thus doesn’t not require any exact numerical model and can handle nonlinearity. This technique provides a framework for the extension to handle multiple special cases for optimized working of the system.Keywords: photovoltaic, power, fuzzy logic, distributed generators, state of charge, load shedding, membership functions
Procedia PDF Downloads 4801304 Anticancer Lantadene Derivatives: Synthesis, Cytotoxic and Docking Studies
Authors: A. Monika, Manu Sharma, Hong Boo Lee, Richa Dhingra, Neelima Dhingra
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Nuclear factor-κappa B serve as a molecular lynchpin that links persistent infections and chronic inflammation to increased cancer risk. Inflammation has been recognized as a hallmark and cause of cancer. Natural products present a privileged source of inspiration for chemical probe and drug design. Herbal remedies were the first medicines used by humans due to the many pharmacologically active secondary metabolites produced by plants. Some of the metabolites like Lantadene (pentacyclic triterpenoids) from the weed Lantana camara has been known to inhibit cell division and showed anti-antitumor potential. The C-3 aromatic esters of lantadenes were synthesized, characterized and evaluated for cytotoxicity and inhibitory potential against Tumor necrosis factor alpha-induced activation of Nuclear factor-κappa B in lung cancer cell line A549. The 3-methoxybenzoyloxy substituted lead analogue inhibited kinase activity of the inhibitor of nuclear factor-kappa B kinase in a single-digit micromolar concentration. At the same time, the lead compound showed promising cytotoxicity against A549 lung cancer cells with IC50 ( half maximal inhibitory concentration) of 0.98l µM. Further, molecular docking of 3-methoxybenzoyloxy substituted analogue against Inhibitor of nuclear factor-kappa B kinase (Protein data bank ID: 3QA8) showed hydrogen bonding interaction involving oxygen atom of 3-methoxybenzoyloxy with the Arginine-31 and Glutamine-110. Encouraging results indicate the Lantadene’s potential to be developed as anticancer agents.Keywords: anticancer, lantadenes, pentacyclic triterpenoids, weed
Procedia PDF Downloads 1561303 Improving Electrical Safety through Enhanced Work Permits
Authors: Nuwan Karunarathna, Hemali Seneviratne
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Distribution Utilities inherently present electrical hazards for their workers in addition to the general public especially due to bare overhead lines spreading out over a large geographical area. Therefore, certain procedures such as; de-energization, verification of de-energization, isolation, lock-out tag-out and earthing are carried out to ensure safe working conditions when conducting maintenance work on de-energized overhead lines. However, measures must be taken to coordinate the above procedures and to ensure successful and accurate execution of those procedures. Issuing of 'Work Permits' is such a measure that is used by the Distribution Utility considered in this paper. Unfortunately, the Work Permit method adopted by the Distribution Utility concerned here has not been successful in creating the safe working conditions as expected which was evidenced by four (4) number of fatalities of workers due to electrocution occurred in the Distribution Utility from 2016 to 2018. Therefore, this paper attempts to identify deficiencies in the Work Permit method and related contributing factors through careful analysis of the four (4) fatalities and work place practices to rectify the short comings to prevent future incidents. The analysis shows that the present level of coordination between the 'Authorized Person' who issues the work permit and the 'Competent Person' who performs the actual work is grossly inadequate to achieve the intended safe working conditions. The paper identifies the need of active participation of a 'Control Person' who oversees the whole operation from a bird’s eye perspective and recommends further measures that are derived through the analysis of the fatalities to address the identified lapses in the current work permit system.Keywords: authorized person, competent person, control person, de-energization, distribution utility, isolation, lock-out tag-out, overhead lines, work permit
Procedia PDF Downloads 1311302 Nondestructive Inspection of Reagents under High Attenuated Cardboard Box Using Injection-Seeded THz-Wave Parametric Generator
Authors: Shin Yoneda, Mikiya Kato, Kosuke Murate, Kodo Kawase
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In recent years, there have been numerous attempts to smuggle narcotic drugs and chemicals by concealing them in international mail. Combatting this requires a non-destructive technique that can identify such illicit substances in mail. Terahertz (THz) waves can pass through a wide variety of materials, and many chemicals show specific frequency-dependent absorption, known as a spectral fingerprint, in the THz range. Therefore, it is reasonable to investigate non-destructive mail inspection techniques that use THz waves. For this reason, in this work, we tried to identify reagents under high attenuation shielding materials using injection-seeded THz-wave parametric generator (is-TPG). Our THz spectroscopic imaging system using is-TPG consisted of two non-linear crystals for emission and detection of THz waves. A micro-chip Nd:YAG laser and a continuous wave tunable external cavity diode laser were used as the pump and seed source, respectively. The pump beam and seed beam were injected to the LiNbO₃ crystal satisfying the noncollinear phase matching condition in order to generate high power THz-wave. The emitted THz wave was irradiated to the sample which was raster scanned by the x-z stage while changing the frequencies, and we obtained multispectral images. Then the transmitted THz wave was focused onto another crystal for detection and up-converted to the near infrared detection beam based on nonlinear optical parametric effects, wherein the detection beam intensity was measured using an infrared pyroelectric detector. It was difficult to identify reagents in a cardboard box because of high noise levels. In this work, we introduce improvements for noise reduction and image clarification, and the intensity of the near infrared detection beam was converted correctly to the intensity of the THz wave. A Gaussian spatial filter is also introduced for a clearer THz image. Through these improvements, we succeeded in identification of reagents hidden in a 42-mm thick cardboard box filled with several obstacles, which attenuate 56 dB at 1.3 THz, by improving analysis methods. Using this system, THz spectroscopic imaging was possible for saccharides and may also be applied to cases where illicit drugs are hidden in the box, and multiple reagents are mixed together. Moreover, THz spectroscopic imaging can be achieved through even thicker obstacles by introducing an NIR detector with higher sensitivity.Keywords: nondestructive inspection, principal component analysis, terahertz parametric source, THz spectroscopic imaging
Procedia PDF Downloads 1771301 Cas9-Assisted Direct Cloning and Refactoring of a Silent Biosynthetic Gene Cluster
Authors: Peng Hou
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Natural products produced from marine bacteria serve as an immense reservoir for anti-infective drugs and therapeutic agents. Nowadays, heterologous expression of gene clusters of interests has been widely adopted as an effective strategy for natural product discovery. Briefly, the heterologous expression flowchart would be: biosynthetic gene cluster identification, pathway construction and expression, and product detection. However, gene cluster capture using traditional Transformation-associated recombination (TAR) protocol is low-efficient (0.5% positive colony rate). To make things worse, most of these putative new natural products are only predicted by bioinformatics analysis such as antiSMASH, and their corresponding natural products biosynthetic pathways are either not expressed or expressed at very low levels under laboratory conditions. Those setbacks have inspired us to focus on seeking new technologies to efficiently edit and refractor of biosynthetic gene clusters. Recently, two cutting-edge techniques have attracted our attention - the CRISPR-Cas9 and Gibson Assembly. By now, we have tried to pretreat Brevibacillus laterosporus strain genomic DNA with CRISPR-Cas9 nucleases that specifically generated breaks near the gene cluster of interest. This trial resulted in an increase in the efficiency of gene cluster capture (9%). Moreover, using Gibson Assembly by adding/deleting certain operon and tailoring enzymes regardless of end compatibility, the silent construct (~80kb) has been successfully refactored into an active one, yielded a series of analogs expected. With the appearances of the novel molecular tools, we are confident to believe that development of a high throughput mature pipeline for DNA assembly, transformation, product isolation and identification would no longer be a daydream for marine natural product discovery.Keywords: biosynthesis, CRISPR-Cas9, DNA assembly, refactor, TAR cloning
Procedia PDF Downloads 2821300 Study of a Cross-Flow Membrane to a Kidney Encapsulation Engineering Structures for Immunosuppression Filter
Authors: Sihyun Chae, Ryoto Arai, Waldo Concepcion, Paula Popescu
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The kidneys perform an important role in the human hormones that regulate the blood pressure, produce an active form of vitamin D and control the production of red blood cells. Kidney disease can cause health problems, such as heart disease. Also, increase the chance of having a stroke or heart attack. There are mainly to types of treatments for kidney disease, dialysis, and kidney transplant. For a better quality of life, the kidney transplant is desirable. However, kidney transplant can cause antibody reaction and patients’ body would be attacked by immune system of their own. For solving that issue, patients with transplanted kidney always take immunosuppressive drugs which can hurt kidney as side effects. Patients willing to do a kidney transplant have a waiting time of 3.6 years in average searching to find an appropriate kidney, considering there are almost 96,380 patients waiting for kidney transplant. There is a promising method to solve these issues: bioartificial kidney. Our membrane is specially designed with unique perforations capable to filter the blood cells separating the white blood cells from red blood cells. White blood cells will not pass through the encapsulated kidney preventing the immune system to attack the new organ and eliminating the need of a matching donor. It is possible to construct life-time long encapsulation without needing pumps or a power supply on the cell’s separation method preventing futures surgeries due the Cross-Channel Flow inside the device. This technology allows the possibility to use an animal kidney, prevent cancer cells to spread through the body, arm and leg transplants in the future. This project aims to improve the quality of life of patients with kidney disease.Keywords: kidney encapsulation, immunosuppression filter, leukocyte filter, leukocyte
Procedia PDF Downloads 2011299 Affect of Reservoir Fluctuations on an Active Landslide in the Xiangjiaba Reservoir Area, Southwest China
Authors: Javed Iqbal
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Filling of Xiangjiaba Reservoir Lake in Southwest China triggered and re-activated numerous landslides due to water fluctuation. In order to understand the relationship between reservoirs and slope instability, a typical reservoir landslide (Dasha landslide) at right bank of Jinsha River was selected as a case study for in-depth investigations. The detailed field investigations were carried out in order to identify the landslide with respect to its surroundings and to find out the slip-surface. Boreholes were drilled in order to find out the subsurface lithology and the depth of failure of Dasha landslide. The in-situ geotechnical tests were performed, and the soil samples from exposed slip surface were retrieved for geotechnical laboratory analysis. Finally, stability analysis was done using 3D strength reduction method under different conditions of reservoir water level fluctuations and rainfall conditions. The in-depth investigations show that the Dasha landslide is a bedding rockslide which was once activated in 1986. The topography of Dasha landslide is relatively flat, while the back scarp and local terrain are relatively steep. The landslide area is about 29 × 104 m², and the maximum thickness of the landslide deposits revealed by drilling is about 40 m with the average thickness being about 20 m, and the volume is thus estimated being about 580 × 10⁴ m³. Bedrock in the landslide area is composed of Suining Formation of Jurassic age. The main rock type is silty mudstone with sandstone, and bedding orientation is 300~310° ∠ 7~22°. The factor of safety (FOS) of Dasha landslide obtained by 3D strength reduction cannot meet the minimum safety requirement under the working condition of reservoir level fluctuation as designed, with effect of rainfall and rapid drawdown.Keywords: Dasha landslide, Xiangjiaba reservoir, strength reduction method, bedding rockslide
Procedia PDF Downloads 1621298 Modeling of in 738 LC Alloy Mechanical Properties Based on Microstructural Evolution Simulations for Different Heat Treatment Conditions
Authors: M. Tarik Boyraz, M. Bilge Imer
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Conventionally cast nickel-based super alloys, such as commercial alloy IN 738 LC, are widely used in manufacturing of industrial gas turbine blades. With carefully designed microstructure and the existence of alloying elements, the blades show improved mechanical properties at high operating temperatures and corrosive environment. The aim of this work is to model and estimate these mechanical properties of IN 738 LC alloy solely based on simulations for projected heat treatment conditions or service conditions. The microstructure (size, fraction and frequency of gamma prime- γ′ and carbide phases in gamma- γ matrix, and grain size) of IN 738 LC needs to be optimized to improve the high temperature mechanical properties by heat treatment process. This process can be performed at different soaking temperature, time and cooling rates. In this work, micro-structural evolution studies were performed experimentally at various heat treatment process conditions, and these findings were used as input for further simulation studies. The operation time, soaking temperature and cooling rate provided by experimental heat treatment procedures were used as micro-structural simulation input. The results of this simulation were compared with the size, fraction and frequency of γ′ and carbide phases, and grain size provided by SEM (EDS module and mapping), EPMA (WDS module) and optical microscope for before and after heat treatment. After iterative comparison of experimental findings and simulations, an offset was determined to fit the real time and theoretical findings. Thereby, it was possible to estimate the final micro-structure without any necessity to carry out the heat treatment experiment. The output of this microstructure simulation based on heat treatment was used as input to estimate yield stress and creep properties. Yield stress was calculated mainly as a function of precipitation, solid solution and grain boundary strengthening contributors in microstructure. Creep rate was calculated as a function of stress, temperature and microstructural factors such as dislocation density, precipitate size, inter-particle spacing of precipitates. The estimated yield stress values were compared with the corresponding experimental hardness and tensile test values. The ability to determine best heat treatment conditions that achieve the desired microstructural and mechanical properties were developed for IN 738 LC based completely on simulations.Keywords: heat treatment, IN738LC, simulations, super-alloys
Procedia PDF Downloads 2481297 Direct Electrical Communication of Redox Enzyme Based on 3-Dimensional Cross-Linked Redox Enzyme/Nanomaterials
Authors: A. K. M. Kafi, S. N. Nina, Mashitah M. Yusoff
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In this work, we have described a new 3-dimensional (3D) network of cross-linked Horseradish Peroxidase/Carbon Nanotube (HRP/CNT) on a thiol-modified Au surface in order to build up the effective electrical wiring of the enzyme units with the electrode. This was achieved by the electropolymerization of aniline-functionalized carbon nanotubes (CNTs) and 4-aminothiophenol -modified-HRP on a 4-aminothiophenol monolayer-modified Au electrode. The synthesized 3D HRP/CNT networks were characterized with cyclic voltammetry and amperometry, resulting the establishment direct electron transfer between the redox active unit of HRP and the Au surface. Electrochemical measurements reveal that the immobilized HRP exhibits high biological activity and stability and a quasi-reversible redox peak of the redox center of HRP was observed at about −0.355 and −0.275 V vs. Ag/AgCl. The electron transfer rate constant, KS and electron transfer co-efficient were found to be 0.57 s-1 and 0.42, respectively. Based on the electrocatalytic process by direct electrochemistry of HRP, a biosensor for detecting H2O2 was developed. The developed biosensor exhibits excellent electrocatalytic activity for the reduction of H2O2. The proposed biosensor modified with HRP/CNT 3D network displays a broader linear range and a lower detection limit for H2O2 determination. The linear range is from 1.0×10−7 to 1.2×10−4M with a detection limit of 2.2.0×10−8M at 3σ. Moreover, this biosensor exhibits very high sensitivity, good reproducibility and long-time stability. In summary, ease of fabrication, a low cost, fast response and high sensitivity are the main advantages of the new biosensor proposed in this study. These obvious advantages would really help for the real analytical applicability of the proposed biosensor.Keywords: redox enzyme, nanomaterials, biosensors, electrical communication
Procedia PDF Downloads 4541296 A Detailed Computational Investigation into Copper Catalyzed Sonogashira Coupling Reaction
Authors: C. Rajalakshmi, Vibin Ipe Thomas
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Sonogashira coupling reactions are widely employed in the synthesis of molecules of biological and pharmaceutical importance. Copper catalyzed Sonogashira coupling reactions are gaining importance owing to the low cost and less toxicity of copper as compared to the palladium catalyst. In the present work, a detailed computational study has been carried out on the Sonogashira coupling reaction between aryl halides and terminal alkynes catalyzed by Copper (I) species with trans-1, 2 Diaminocyclohexane as ligand. All calculations are performed at Density Functional Theory (DFT) level, using the hybrid Becke3LYP functional. Cu and I atoms are described using an effective core potential (LANL2DZ) for the inner electrons and its associated double-ζ basis set for the outer electrons. For all other atoms, 6-311G+* basis set is used. We have identified that the active catalyst species is a neutral 3-coordinate trans-1,2 diaminocyclohexane ligated Cu (I) alkyne complex and found that the oxidative addition and reductive elimination occurs in a single step proceeding through one transition state. This is owing to the ease of reductive elimination involving coupling of Csp2-Csp carbon atoms and the less stable Cu (III) intermediate. This shows the mechanism of copper catalyzed Sonogashira coupling reactions are quite different from those catalyzed by palladium. To gain further insights into the mechanism, substrates containing various functional groups are considered in our study to traverse their effect on the feasibility of the reaction. We have also explored the effect of ligand on the catalytic cycle of the coupling reaction. The theoretical results obtained are in good agreement with the experimental observation. This shows the relevance of a combined theoretical and experimental approach for rationally improving the cross-coupling reaction mechanisms.Keywords: copper catalysed, density functional theory, reaction mechanism, Sonogashira coupling
Procedia PDF Downloads 1161295 Nation Branding as Reframing: From the Perspective of Translation Studies
Authors: Ye Tian
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Soft power has replaced hard power and become one of the most attractive ways nations pursue to expand their international influence. One of the ways to improve a nation’s soft power is to commercialise the country and brand or rebrand it to the international audience, and thus attract interests or foreign investments. In this process, translation has often been regarded as merely a tool, and researches in it are either in translating literature as culture export or in how (in)accuracy of translation influences the branding campaign. This paper proposes to analyse nation branding campaign with framing theory, and thus gives an entry for translation studies to come to a central stage in today’s soft power research. To frame information or elements of a text, an event, or, as in this paper, a nation is to put them in a mental structure. This structure can be built by outsiders or by those who create the text, the event, or by citizens of the nation. To frame information like this can be regarded as a process of translation, as what translation does in its traditional meaning of ‘translating a text’ is to put a framework on the text to, deliberately or not, highlight some of the elements while hiding the others. In the discourse of nations, then, people unavoidably simplify a national image and put the nation into their imaginary framework. In this way, problems like stereotype and prejudice come into being. Meanwhile, if nations seek ways to frame or reframe themselves, they make efforts to have in control what and who they are in the eyes of international audiences, and thus make profits, economically or politically, from it. The paper takes African nations, which are usually perceived as a whole, and the United Kingdom as examples to justify passive and active framing process, and assesses both positive and negative influence framing has on nations. In conclusion, translation as framing causes problems like prejudice, and the image of a nation is not always in the hands of nation branders, but reframing the nation in a positive way has the potential to turn the tide.Keywords: framing, nation branding, stereotype, translation
Procedia PDF Downloads 1551294 Antiproliferative Effect of Polyphenols from Crocus sativus L. Leaves on Human Colon Adenocarcinoma Cells (Caco-2)
Authors: Gonzalo Ortiz de Elguea-Culebras, Raúl Sánchez-Vioquea, Adela Mena-Morales, Manuel Alaiz, Enrique Melero-Bravo, Esteban García-Romero, Javier Vioque, Lourdes Marchante-Cuevas, Julio Girón-Calle
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Saffron (Crocus sativus L.) is a highly valued crop for the manufacture of spice that consists of the dried stigma of the flowers. This is in contrast to other underutilized parts of the saffron plant as leaves, which represent abundant biomass whose use might help to enhance the sustainability of the saffron crop. Saffron leaves contain significant amounts of phenolic compounds, 7.8 equivalent grams of gallic acid per 100g of extract, and are very promising compounds in terms of exploring novel uses of saffron leaves. Given that phenolic compounds have numerous effects on cancer-related biological pathways, we have investigated the in vitro antiproliferative effect of saffron leaf polyphenols against human colon adenocarcinoma cells (Caco-2). Polyphenols were extracted from leaves with 70% ethanol, defatted with hexane, and purified by solid phase extraction using C18 silica gel and then silica gel 60. Analysis of polyphenols was performed by HPLC-ESI-MS. Di-, tri-, and tetrahexosides of quercetin, kaempferol, and isorhamnetin, as well as C-hexosides like isoorientin and vitexin, were tentatively identified. Polyphenols strongly inhibited the proliferation of Caco-2 cells, which is consistent with model studies in which several of the polyphenols identified in saffron leaves have demonstrated their potential as chemopreventive agents in cancer. Due to the low profitability that saffron leaf currently represents, we consider these results very encouraging and that this by-product deserves further investigation as a potential source of active molecules against colorectal cancer.Keywords: saffron leaves, agricultural by-products, polyphenols, antiproliferative effect, human colon adenocarcinoma cells
Procedia PDF Downloads 941293 A Study on Selfie Culture, Social Media Engagement, Self-Image, and Young Adult Mental Well-being
Authors: Sumaiyya Ali, Humaira Jamshed
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Selfie culture has become increasingly prevalent in recent years, with young adults being one of the most active demographics when it comes to taking and sharing selfies. While some argue that selfies can be a harmless way to express oneself, connect with others, and boost self-esteem, others have raised concerns about the potential negative effects of selfie culture on mental health. This study investigated the complex relationship between selfie culture, social media use, self-image, and mental well-being among young adults. A cross-sectional survey was conducted with over 75 participants aged 18–30. The results of the study showed that there is a positive relationship between selfie culture and social media use and that both of these factors are associated with lower self-esteem, higher self-consciousness, and increased appearance anxiety among young adults. Additionally, the study found that selfie culture was associated with increased narcissistic traits among young adults. The findings of this study suggest that selfie culture may have some negative effects on the mental health of young adults. However, it is important to note that the study was cross-sectional, which means that it cannot establish causality. Future research is needed to further investigate the relationship between selfie culture and mental health. In addition to the findings of the study, it is also important to consider the motivation behind selfie-taking. The study identified four main motivations for taking selfies: to communicate with others, to promote oneself, to express oneself, and to seek attention. It is likely that the negative effects of selfie culture are more pronounced for individuals who take selfies for narcissistic or attention-seeking reasons. Overall, the findings of this study suggest that selfie culture is a complex phenomenon with both positive and negative potential effects on the mental health of young adults. It is important to be aware of the potential risks associated with selfie culture, and to use it in a healthy and balanced way.Keywords: selfie, social media, psychology, mental health
Procedia PDF Downloads 161292 Synthesis and Analytical Characterisation of Polymer-Silica Nanoparticles Composite for the Protection and Preservation of Stone Monuments
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
Procedia PDF Downloads 2501291 Dynamic Analysis of Functionally Graded Nano Composite Pipe with PZT Layers Subjected to Moving Load
Authors: Morteza Raminnia
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In this study, dynamic analysis of functionally graded nano-composite pipe reinforced by single-walled carbon nano-tubes (SWCNTs) with simply supported boundary condition subjected to moving mechanical loads is investigated. The material properties of functionally graded carbon nano tube-reinforced composites (FG-CNTRCs) are assumed to be graded in the thickness direction and are estimated through a micro-mechanical model. In this paper polymeric matrix considered as isotropic material and for the CNTRC, uniform distribution (UD) and three types of FG distribution patterns of SWCNT reinforcements are considered. The system equation of motion is derived by using Hamilton's principle under the assumptions of first order shear deformation theory (FSDT).The thin piezoelectric layers embedded on inner and outer surfaces of FG-CNTRC layer are acted as distributed sensor and actuator to control dynamic characteristics of the FG-CNTRC laminated pipe. The modal analysis technique and Newmark's integration method are used to calculate the displacement and dynamic stress of the pipe subjected to moving loads. The effects of various material distribution and velocity of moving loads on dynamic behavior of the pipe is presented. This present approach is validated by comparing the numerical results with the published numerical results in literature. The results show that the above-mentioned effects play very important role on dynamic behavior of the pipe .This present work shows that some meaningful results that which are interest to scientific and engineering community in the field of FGM nano-structures.Keywords: nano-composite, functionally garded material, moving load, active control, PZT layers
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