Search results for: barrier coatings
423 Expand Rabies Post-Exposure Prophylaxis to Where It Is Needed the Most
Authors: Henry Wilde, Thiravat Hemachudha
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Human rabies deaths are underreported worldwide at 55,000 annual cases; more than of dengue and Japanese encephalitis. Almost half are children. A recent study from the Philippines of nearly 2,000 rabies deaths revealed that none of had received incomplete or no post exposure prophylaxis. Coming from a canine rabies endemic country, this is not unique. There are two major barriers to reducing human rabies deaths: 1) the large number of unvaccinated dogs and 2) post-exposure prophylaxis (PEP) that is not available, incomplete, not affordable, or not within reach for bite victims travel means. Only the first barrier, inadequate vaccination of dogs, is now being seriously addressed. It is also often not done effectively or sustainably. Rabies PEP has evolved as a complex, prolonged process, usually delegated to centers in larger cities. It is virtually unavailable in villages or small communities where most dog bites occur, victims are poor and usually unable to travel a long distance multiple times to receive PEP. Reseacrh that led to better understanding of the pathophysiology of rabies and immune responses to potent vaccines and immunoglobulin have allowed shortening and making PEP more evidence based. This knowledge needs to be adopted and applied so that PEP can be rendered safely and affordably where needed the most: by village health care workers who have long performed more complex services after appropriate training. Recent research makes this an important and long neglected goal that is now within our means to implement.Keywords: rabies, post-exposure prophylaxis, availability, immunoglobulin
Procedia PDF Downloads 264422 The Postcolonial Everyday: the Construction of Daily Barriers in the Experience of Asylum Seekers and Refugees in the UK
Authors: Sarah Elmammeri
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This paper will represent the postcolonial every day in the journey of asylum seekers through the asylum process in the UK. It represents everyday borders, which are defined as everyday barriers, and obstacles facing asylum seekers and refugees in the host country. These everyday barriers can be legal, financial, social and educational under the umbrella of the racialized administrative border creating a package. The arguments build on a set of 21 semi-structured interviews in English and Arabic. The interviews were conducted in the UK, online via zoom lasting between 25 minutes and 2 hours with asylum seekers, refugees, Non-governmental organisations workers and volunteers. The interviews focus on the meaning of borders both physical and metaphorical and ways to challenge the ongoing postcolonial everyday border practices. The findings conclude that these barriers are there deliberately and intentionally to target asylum seekers and limit their legal right to claim asylum in a form of policy and regulations. People in the asylum process, NGO workers, and refugees relate to this aspect of the everyday borders. Second, these barriers come intertwined together creating a structure that interferes with the daily life of an asylum seeker and later affects people with refugee status creating racialised barriers starting with the structural and official form of it: the asylum process. These structural barriers will be linked forming a multi-level barrier enhancing the racialisation of people who are categorised and selected.Keywords: everyday borders, asylum policies, inclusion and exclusion, refugees and asylum seekers
Procedia PDF Downloads 121421 SPPO-Based Cation Exchange Membranes with a Positively Charged Layer for Cation Fractionation
Authors: Noor Ul Afsar, Wengen Ji, Bin Wu, Muhammad A. Shehzad, Liang Ge, Tongwen Xu
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The synthesis of monovalent cation perm-selective membranes (MCPMs) to efficiently discriminate amongst cations from seawater is of great importance for several industrial applications. However, a technical approach is highly desired to construct MCPMs to obtain a high ionic flux and sustain perm-selectivity simultaneously. In the present work, the thickness of the quaternized poly (2, 6-dimethyl-1, 4-phenylene oxide) (QPPO) layer on the surface of the SPPO-PVA (SPVA) composite membrane was adjusted using a facile procedure to achieve high permselectivity without scarifying the ionic flux. The thickness of the selective layer was precisely controlled using various concentrations of the QPPO solution. By the introduction of the cationic layer on the SPVA membrane, the monovalent cation can be separated from the divalent cation by their difference in charge density. The influence of the selective barrier (thickness) endows MCPMs with high perm-selectivity up to 12.7 for 0.1 mol L⁻¹ Li⁺/Mg²⁺ system, which is very satisfactory for polymeric membranes. The fabricated membranes have low electrical resistance and high limiting current density (iₗᵢₘ). Keeping in view the ED results, the prepared membranes with selective surface layers could be a viable candidate for Li⁺ selective separation from divalent cation Mg²⁺.Keywords: monovalent cation perm-selective membranes, cation fractionation, perm-selectivity, ionic flux, electrodialysis
Procedia PDF Downloads 72420 The Study of Dissolving Microneedle Patch for Androgenetic Alopecia
Authors: Li-Yu Lee, Yu-Shuan Chen, Jun Sheng Wang, I-Ming Chu
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Microneedle patch is a painless transdermal drug delivery method, It could solve some problems in traditional drug delivery such as digestive system causing drug metabolism and subcutaneous injection causing some side effects. Coating drug on or loading drug in microneedle can carry active ingredient through stratum corneum, also can control dose well when microneedle patch apply on localized topical area. We used hyaluronic acid to fabricate dissolvable microneedle patch and encapsulated minoxidil into microneedles. Minoxdil is a drug for exterior use that can be used to treat Androgenetic alopecia, but related commercial products have some shortcomings, for example, propylene glycol which is used to soften stratum corneum cause skin allergic reaction, comparing chemical promotion, microneedle patch provide physical way to make drugs through nature barrier of skin. In this research, we designed a two-step process to fabricate microneedle patch, that can effectively reduce drug waste, and gentle production process could maintain drug activity well. We also do in vitro test on cadaver to make sure patch has enough mechanical strength to penetrate stratum corneum. In the release test and animal test, we found microneedle patch has higher delivery efficiency than tradition way. In this study, we may determine that germinal MNs patch is a potential commodity.Keywords: dissolving microneedles, androgenetic alopecia, minoxidil, transdermal drug delivery
Procedia PDF Downloads 280419 Insect Inducible Methanol Production in Plants for Insect Resistance
Authors: Gourav Jain, Sameer Dixit, Surjeet Kumar Arya, Praveen C. Verma
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Plant cell wall plays a major role in defence mechanism against biotic and abiotic stress as it constitutes the physical barrier between the microenvironment and internal component of the cell. It is a complex structure composed of mostly carbohydrates among which cellulose and hemicelluloses are most abundant that is embedded in a matrix of pectins and proteins. Multiple enzymes have been reported which plays a vital role in cell wall modification, Pectin Methylesterase (PME) is one of them which catalyses the demethylesterification of homogalacturonans component of pectin which releases acidic pectin and methanol. As emitted methanol is toxic to the insect pest, we use PME gene for the better methanol production. In the current study we showed overexpression of PME gene isolated from Withania somnifera under the insect inducible promoter causes enhancement of methanol production at the time of insect feeds to plants, and that provides better insect resistance property. We found that the 85-90% mortality causes by transgenic tobacco in both chewing (Spodoptera litura larvae and Helicoverpa armigera) and sap-sucking (Aphid, mealybug, and whitefly) pest. The methanol content and emission level were also enhanced by 10-15 folds at different inducible time point interval (15min, 30min, 45min, 60min) which would be analysed by Purpald/Alcohol Oxidase method.Keywords: methanol, Pectin methylesterase, inducible promoters, Purpald/Alcohol oxidase
Procedia PDF Downloads 244418 Identification of Hedgerows in the Agricultural Landscapes of Mugada within Bartın Province, Turkey
Authors: Yeliz Sarı Nayim, B. Niyami Nayim
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Biotopes such as forest areas rich in biodiversity, wetlands, hedgerows and woodlands play important ecological roles in agricultural landscapes. Of these semi-natural areas and features, hedgerows are the most common landscape elements. Their most significant features are that they serve as a barrier between the agricultural lands, serve as shelter, add aesthetical value to the landscape and contribute significantly to the wildlife and biodiversity. Hedgerows surrounding agricultural landscapes also provide an important habitat for pollinators which are important for agricultural production. This study looks into the identification of hedgerows in agricultural lands in the Mugada rural area within Bartın province, Turkey. From field data and-and satellite images, it is clear that in this area, especially around rural settlements, large forest areas have been cleared for settlement and agriculture. A network of hedgerows is also apparent, which might potentially play an important role in the otherwise open agricultural landscape. We found that these hedgerows serve as an ecological and biological corridor, linking forest ecosystems. Forest patches of different sizes and creating a habitat network across the landscape. Some examples of this will be presented. The overall conclusion from the study is that ecologically, biologically and aesthetically important hedge biotopes should be maintained in the long term in agricultural landscapes such as this. Some suggestions are given for how they could be managed sustainably into the future.Keywords: agricultural biotopes, Hedgerows, landscape ecology, Turkey
Procedia PDF Downloads 307417 Application of the EU Commission Waste Management Methodology Level(s) to a Construction and a Demolition in North-West Romania.
Authors: Valean Maria
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Construction and demolition waste management is a timely topic, due to the urgency of its transition to sustainability. This sector is responsible for over a third of the waste generated in the E.U., while the legislation requires a proportion of at least 70% preparation for reuse and recycle, excluding backfilling. To this end, the E.U. Commission has provided the Level(s) methodology, allowing for the standardized planning and reporting of waste quantities across all levels of the construction process, from the architecture, to the demolition, from the estimation stage, to the actual measurements at the end of the operations. We applied Level(s) for the first time to the Romanian context, a developing E.U. country in which illegal dumping of contruction waste in nature and landfills, are still common practice. We performed the desk study of the buildings’ documents, followed by field studies of the sites, and finally the insertion and calculation of statistical data of the construction and demolition waste. We learned that Romania is far from the E.U. average in terms of the initial estimations of waste, with some numbers being higher, others lower, and that the price of evacuation to landfills is significantly lower in the developing country, a possible barrier to adopting the new regulations. Finally, we found that concrete is the predominant type waste, in terms of quantity as well as cost of disposal. Further directions of research are provided, such as mapping out all of the alternative facilities in the region and the calculation of the financial costs and of the CO2 footprint, for preparing and delivering waste sustainably, for a more sound and locally adapted model of waste management.Keywords: construction, waste, management, levels, EU
Procedia PDF Downloads 77416 Formulation and in Vitro Characterization of Bioactives Loaded Polymeric Nanoparticle Incorporated into Multiphase Hydrogel System for the Treatment of Infected Burn Wound
Authors: Rajni Kant Panik, Deependra Singh, Manju Singh
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Despite significant advances in the treatment of severe burn injury, infection and sepsis persist as frequent causes of morbidity and mortality for burn victims due to extensive compromise of the skin and contiguous tissue that serve as a protective barrier against microbial invasion. In the setting of a burn wound infection, Staphylococcus aureus is the most commonly isolated pathogens from bloodstream infections in burn care hospitals. We aimed to develop a biocompatible system of Poly vinyl alcohol (PVA)-sodium alginate hydrogel carrying multiple drugs- catalase and mupirocin in controlled manner for effective and complete burn wound healing. PLGA nanoparticles of Catalase and mupirocin were prepared by homogenization method and optimized system was incorporated in PVA-sodium alginate slurry. PVA-sodium alginate hydrogels were prepared by freeze thaw method. The prepared dispersion was casted into films to prepare multiphase hydrogel system and characterized by in vitro and in vivo studies. The study clearly showed the beneficial effect of antioxidant enzyme and antibiotic in the treatment of infected burn wound, as evidenced by the reduced incidence of wound infection and the shortening of healing time.Keywords: burn wound, catalase, mupirocin, wound healing
Procedia PDF Downloads 503415 Factors Affecting Customer Loyalty in the Independent Surveyor Service Industry in Indonesia
Authors: Sufrin Hannan, Budi Suharjo, Rita Nurmalina, Kirbrandoko
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The challenge for independent surveyor service companies now is growing with increasing uncertainty in business. Protection from the government for domestic independent surveyor industry from competitor attack, such as entering the global surveyors to Indonesia also no longer exists. Therefore, building customer loyalty becomes very important to create a long-term relationship between an independent surveyor with its customers. This study aims to develop a model that can be used to build customer loyalty by looking at various factors that determine customer loyalty, especially on independent surveyors for coal inspection in Indonesia. The development of this model uses the relationship marketing approach. Testing of the hypothesis is done by testing the variables that determine customer loyalty, either directly or indirectly, which amounted to 10 variables. The data were collected from 200 questionnaires filled by independent surveyor company decision makers from 51 exporting companies and coal trading companies in Indonesia and analyzed using Structural Equation Model (SEM). The results show that customer loyalty of independent surveyors is influenced by customer satisfaction, trust, switching-barrier, and relationship-bond. Research on customer satisfaction shows that customer satisfaction is influenced by the perceived quality and perceived value, while perceived quality is influenced by reliability, assurance, responsiveness, and empathy.Keywords: relationship marketing, customer loyalty, customer satisfaction, switching barriers, relationship bonds
Procedia PDF Downloads 169414 Muscle Relaxant Dantrolene Repurposed to Treat Alzheimer's Disease
Authors: Huafeng Wei
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Failures of developing new drugs primarily based on the amyloid pathology hypothesis after decades of efforts internationally lead to changes of focus targeting alternative pathways of pathology in Alzheimer’s disease (AD). Disruption of intracellular Ca2+ homeostasis, especially the pathological and excessive Ca2+ release from the endoplasmic reticulum (ER) via ryanodine receptor (RyRs) Ca2+ channels, has been considered an upstream pathology resulting in major AD pathologies, such as amyloid and Tau pathology, mitochondria damage and inflammation, etc. Therefore, dantrolene, an inhibitor of RyRs that reduces the pathological Ca2+ release from ER and a clinically available drug for the treatment of malignant hyperthermia and muscle spasm, is expected to ameliorate AD multiple pathologies synapse and cognitive dysfunction. Our own studies indicated that dantrolene ameliorated impairment of neurogenesis and synaptogenesis in neurons developed from induced pluripotent stem cells (iPSCs) originated from skin fibroblasts of either familiar (FAD) or sporadic (SAD) AD by restoring intracellular Ca2+ homeostasis. Intranasal administration of dantrolene significantly increased its passage across the blood-brain barrier (BBB) and, therefore its brain concentrations and durations. This can render dantrolene a more effective therapeutic drug with fewer side effects for chronic AD treatment. This review summarizes the potential therapeutic and side effects of dantrolene and repurposes intranasal dantrolene as a disease-modifying drug for future AD treatment.Keywords: Alzheimer's disease, calcium, drug development, dementia, neurodegeneration, neurogenesis
Procedia PDF Downloads 209413 A Comparative Study on Electrical Characteristics of Au/n-SiC structure, with and Without Zn-Doped PVA Interfacial Layer at Room Temperature
Authors: M. H. Aldahrob, A. Kokce, S. Altindal, H. E. Lapa
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In order to obtain the detailed information about the effect of (Zn-doped PVA) interfacial layer, surface states (Nss) and series resistance (Rs) on electrical characteristics, both Au/n- type 4H-SiC (MS) with and without (Zn doped PVA) interfacial layer were fabricated to compare. The main electrical parameters of them were investigated using forward and reverse bias current-voltage (I-V), capacitance-voltage (C-V) and conductance –voltage (G/W –V) measurements were performed at room temperature. Experimental results show that the value of ideality factor (n), zero –bias barrier height (ΦBo), Rs, rectifier rate (RR=IF/IR) and the density of Nss are strong functions interfacial layer and applied bias voltage. The energy distribution profile of Nss was obtained from forward bias I-V data by taking into account voltage dependent effective BH (ΦBo) and ideality factor (n(V)). Voltage dependent profile of Rs was also obtained both by using Ohm’s law and Nicollian and Brew methods. The other main diode parameters such as the concentration of doping donor atom (ND), Fermi energy level (EF).BH (ΦBo), depletion layer with (WD) were obtained by using the intercept and slope of the reverse bias C-2 vs V plots. It was found that (Zn-doped PVA) interfacial layer lead to a quite decrease in the values Nss, Rs and leakage current and increase in shunt resistance (Rsh) and RR. Therefore, we can say that the use of thin (Zn-doped PVA) interfacial layer can quite improved the performance of MS structure.Keywords: interfacial polymer layer, thickness dependence, electric and dielectric properties, series resistance, interface state
Procedia PDF Downloads 249412 The Importance of a Coating and Architecture of the Surface Metal on the Survival of Uncemented Total Knee Arthroplasty
Authors: Raymond Puijk, Rachid Rassir, Inger N. Sierevelt, Anneke Spekenbrink-Sporen, Bart G. C. W. Pijls, Rob G. H. H. Nelissen, Peter A. Nolte
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Background: Among uncemented total knee arthroplasty (TKA), a wide variety of metal surface structures (MSS) and coatings exist to enhance implants' biological properties (i.e., bone ingrowth). This study explores the variety of MSS-coating combinations and compares their mid-long-term survivorships with cemented TKAs, by using data from the Dutch Arthroplasty Register. Methods: A total of 235,500 cemented and 11,132 uncemented primary TKAs with a median follow-up of 5.1 years were included. MSS-coating combinations were (1) Porous-uncoated (n=8986), (2) Beaded-hydroxyapatite (HA)(n=1093), (3) Matte-uncoated (n=846), (4) Matte-Titanium-nitride (TiN) (n=207). Five- and 10-year revision-free survival for all-cause revisions, and aseptic loosening of the tibial component, were calculated and compared by using Kaplan-Meier, Log-rank tests, and multivariable Cox proportional hazard regression analyses. Results: Ten-year survival rates with all-cause revisions as an endpoint, were 94.2% for cement, and 94.7%, 96.3%, 92.1%, and 79.0% for porous-uncoated, beaded-HA, matte-uncoated, and Matte-TiN, respectively (p<0.01). Rates for aseptic loosening were 98.8% for cemented, and 98.7%, 99.8%, 97.2%, and 94.9% for the uncemented, respectively (p<0.01).The beaded-HA implants were half the risk for an all-cause revision compared to cemented implants (p<0.01). Matte-uncoated and matte-TiN implants were at more risk of an all-cause revision than cemented implants (p=0.01, p<0.01). Proportions of revisions for aseptic loosening were comparable among most groups. Conclusion: Based on Dutch registry data, four main MSS-coating combinations among uncemented TKAs were found. survivorships for all-cause revisions and aseptic release differed widely between groups. Beaded-HA and porous-uncoated implants had the best survival rates among the uncemented TKAs and were non-inferior to the cemented TKAs.Keywords: total knee arthroplasty, cement, uncemented, cementless;, metal surface structure, coating
Procedia PDF Downloads 152411 Electrical Properties of Polarization-Induced Aluminum Nitride/Gallium Nitride Heterostructures Homoepitaxially Grown on Aluminum Nitride Sapphire Template by Molecular Beam Epitaxy
Authors: Guanlin Wu, Jiajia Yao, Fang Liu, Junshuai Xue, Jincheng Zhang, Yue Hao
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Owing to the excellent thermal conductivity and ultra-wide bandgap, Aluminum nitride (AlN)/Gallium nitride (GaN) is a highly promising material to achieve high breakdown voltage and output power devices among III-nitrides. In this study, we explore the growth and characterization of polarization-induced AlN/GaN heterostructures using plasma-assisted molecular beam epitaxy (PA-MBE) on AlN-on-sapphire templates. To improve the crystal quality and demonstrate the effectiveness of the PA-MBE approach, a thick AlN buffer of 180 nm was first grown on the AlN-on sapphire template. This buffer acts as a back-barrier to enhance the breakdown characteristic and isolate leakage paths that exist in the interface between the AlN epilayer and the AlN template. A root-mean-square roughness of 0.2 nm over a scanned area of 2×2 µm2 was measured by atomic force microscopy (AFM), and the full-width at half-maximum of (002) and (102) planes on the X-ray rocking curve was 101 and 206 arcsec, respectively, using by high-resolution X-ray diffraction (HR-XRD). The electron mobility of 443 cm2/Vs with a carrier concentration of 2.50×1013 cm-2 at room temperature was achieved in the AlN/GaN heterostructures by using a polarization-induced GaN channel. The low depletion capacitance of 15 pF is resolved by the capacitance-voltage. These results indicate that the polarization-induced AlN/GaN heterostructures have great potential for next-generation high-temperature, high-frequency, and high-power electronics.Keywords: AlN, GaN, MBE, heterostructures
Procedia PDF Downloads 85410 A Critical Examination of the Relationship between the Media and the Political Agenda in the Social Deviance Portrayal of Disabled People
Authors: Cara Williams
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This paper considers the media’s role in formulating a dominant social deviance paradigm and medicalised portrayal of disabled people and examines how those representations of impairment reinforce the personal tragedy view that underpins the social value given to the category of disability. According to a materialist perspective, the personal tragedy medical model approach condemns disabled people to live an inferior 'life apart', socially excluded and prevented from living as fully participating citizens on an equal basis to non-disabled people. Commonly, disabled people are portrayed as a person who needs to be cured in order to achieve a better 'quality of life'; otherwise stories center on deviance, criminality or scrounger. Media representations have consistently used negative language and images that reinforce the personal tragedy 'deficient' view of disability. The systematic misrepresentation within film, literature, TV and other art forms have validated a process about what it means to be 'normal' and how 'difference' and 'identity' are interpreted. The impact of these stereotyped disabling images for disabled people is a barrier not experienced by many other oppressed minority groups. Applying a materialist analysis, this paper contends that the impact on audience’s perceptions of impaired bodies and minds, and the harmful effects on disabled people can be linked with agenda setting theory - the relationship between the media and the political agenda.Keywords: media, disabled people, political agenda, personal tragedy
Procedia PDF Downloads 147409 Extended Shelf Life of Chicken Meat Using Carboxymethyl Cellulose Coated Polypropylene Films Containing Zataria multiflora Essential Oil
Authors: Z. Honarvar, M. Farhoodi, M. R. Khani, S. Shojaee-Aliabadi
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The purpose of the present study was to evaluate carboxymethyl cellulose (CMC) coated polypropylene (PP) films containing Zataria multiflora (ZEO) essential oils (4%) as an antimicrobial packaging for chicken breast stored at 4 °C. To increase PP film hydrophilicity, it was treated by atmospheric cold plasma prior to coating by CMC. Then, different films including PP, PP/CMC, PP/CMC containing 4% of ZEO were used for the chicken meat packaging in vapor phase. Total viable count and pseudomonads population and oxidative (TBA) changes of the chicken breast were analyzed during shelf life. Results showed that the shelf life of chicken meat kept in films containing ZEO improved from three to nine days compared to the control sample without any direct contact with the film. Study of oxygen barrier properties of bilayer film without essential oils (0.096 cm3 μm/m2 d kPa) in comparison with PP film (416 cm3 μm/m2 d kPa) shows that coating of PP with CMC significantly reduces oxygen permeation of the obtained packaging (P<0.05), which reduced aerobic bacteria growth. Chemical composition of ZEO was also evaluated by gas chromatography–mass spectrometry (GC–MS), and this shows that thymol was the main antimicrobial and antioxidant component of the essential oil. The results revealed that PP/CMC containing ZEO has good potential for application as active food packaging in indirect contact which would also improve sensory properties of product.Keywords: shelf life, chicken breast, polypropylene, carboxymethyl cellulose, essential oil
Procedia PDF Downloads 237408 An Electrode Material for Ultracapacitors: Hydrothermal Synthesis of Neodymium Oxide/Manganese Oxide/Nitrogen Doped Reduced Graphene Oxide Ternary Nanocomposites
Authors: K. Saravanan, K. A.Rameshkumar, P. Maadeswaran
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The depletion of fossil resources and the rise in global temperatures are two of the most important concerns we confront today. There are numerous renewable energy sources like solar power, tidal power, wind energy, radiant energy, hydroelectricity, geothermal energy, and biomass available to generate the needed energy demand. Engineers and scientists around the world are facing a massive barrier in the development of storage technologies for the energy developed from renewable energy sources. The development of electrochemical capacitors as a future energy storage technology is at the forefront of current research and development. This is due to the fact that the electrochemical capacitors have a significantly higher energy density, a faster charging-discharging rate, and a longer life span than capacitors, and they also have a higher power density than batteries, making them superior to both. In this research, electrochemical capacitors using the Nd2O3/Mn3O4/ N-rGO electrode material is chosen since the of hexagonal and tetragonal crystal structures of Nd2O3 and Mn3O4 and also has cycling stability of 68% over a long time at 50mVs-1 and a high coulombic efficiency of 99.64% at 5 Ag-1. This approach may also be used to create novel electrode materials with improved electrochemical and cyclic stability for high-performance supercapacitors.Keywords: Nd2O3/Mn3O4/N-rGO, nanocomposites, hydrothermal method, electrode material, specific capacitance, use of supercapacitors
Procedia PDF Downloads 96407 A Low Cost Gain-Coupled Distributed Feedback Laser Based on Periodic Surface p-Contacts
Authors: Yongyi Chen, Li Qin, Peng Jia, Yongqiang Ning, Yun Liu, Lijun Wang
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The distributed feedback (DFB) lasers are indispensable in optical phase array (OPA) used for light detection and ranging (LIDAR) techniques, laser communication systems and integrated optics, thanks to their stable single longitudinal mode and narrow linewidth properties. Traditional index-coupled (IC) DFB lasers with uniform gratings have an inherent problem of lasing two degenerated modes. Phase shifts are usually required to eliminate the mode degeneration, making the grating structure complex and expensive. High-quality antireflection (AR) coatings on both lasing facets are also essential owing to the random facet phases introduced by the chip cleavage process, which means half of the lasing energy is wasted. Gain-coupled DFB (GC-DFB) lasers based on the periodic gain (or loss) are announced to have single longitudinal mode as well as capable of the unsymmetrical coating to increase lasing power and efficiency thanks to facet immunity. However, expensive and time-consuming technologies such as epitaxial regrowth and nanoscale grating processing are still required just as IC-DFB lasers, preventing them from practical applications and commercial markets. In this research, we propose a low-cost, single-mode regrowth-free GC-DFB laser based on periodic surface p-contacts. The gain coupling effect is achieved simply by periodic current distribution in the quantum well caused by periodic surface p-contacts, introducing very little index-coupling effect that can be omitted. It is prepared by i-line lithography, without nanoscale grating fabrication or secondary epitaxy. Due to easy fabrication techniques, it provides a method to fabricate practical low cost GC-DFB lasers for widespread practical applications.Keywords: DFB laser, gain-coupled, low cost, periodic p-contacts
Procedia PDF Downloads 128406 The Great Mimicker: A Case of Disseminated Tuberculosis
Authors: W. Ling, Mohamed Saufi Bin Awang
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Introduction: Mycobacterium tuberculosis post a major health problem worldwide. Central nervous system (CNS) infection by mycobacterium tuberculosis is one of the most devastating complications of tuberculosis. Although with advancement in medical fields, we are yet to understand the pathophysiology of how mycobacterium tuberculosis was able to cross the blood-brain barrier (BBB) and infect the CNS. CNS TB may present with nonspecific clinical symptoms which can mimic other diseases/conditions; this is what makes the diagnosis relatively difficult and challenging. Public health has to be informed and educated about the spread of TB, and early identification of TB is important as it is a curable disease. Case Report: A young 21-year-old Malay gentleman was initially presented to us with symptoms of ear discharge, tinnitus, and right-sided headache for the past one year. Further history reveals that the symptoms have been mismanaged and neglected over the period of 1 year. Initial investigation reveals features of inflammation of the ear. Further imaging showed the feature of chronic inflammation of the otitis media and atypical right cerebral abscess, which has the same characteristic features and consistency. He further underwent a biopsy, and results reveal positive Mycobacterium tuberculosis of the otitis media. With the results and the available imaging, we were certain that this is likely a case of disseminated tuberculosis causing CNS TB. Conclusion: We aim to highlight the challenge and difficult face in our health care system and public health in early identification and treatment.Keywords: central nervous system tuberculosis, intracranial tuberculosis, tuberculous encephalopathy, tuberculous meningitis
Procedia PDF Downloads 190405 Teachers Handbook: A Key to Imparting Teaching in Multilingual Classrooms at Kalinga Institute of Social Sciences (KISS)
Authors: Sushree Sangita Mohanty
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The pedagogic system, which is used to work with indigenous groups, who have equally different socio-economic, socio-cultural & multi-lingual conditions with differing cognitive capabilities, makes the education situation complex. As a result, educating the indigenous people became just the dissemination of facts and information, but advancement in knowledge and possibilities somewhere hides. This gap arises complexities due to the language barrier and the teachers from a conventional background of teaching practices are unable to understand or connect with the students in the schools. This paper presents the research work of the Mother Tongue Based Multilingual Education (MTB-MLE) project that has developed a creative pedagogic endeavor for the students of Kalinga Institute of Social Sciences (KISS) for facilitating Multilingual Education (MLE) teaching. KISS is a home for 25,000 indigenous children. The students enrolled here are from 62 different indigenous communities who speak around 24 different languages with geographical articulation. The book contents include concept, understanding languages, similitudes among languages, the need of mother tongue in teaching and learning, skill development (Listening-Speaking-Reading-Writing), teachers activities for teaching in multilingual schools, the process of teaching, training format of multilingual teaching and procedures for basic data collection regarding multilingual schools and classroom handle.Keywords: indigenous, multi-lingual, pedagogic, teachers, teaching practices
Procedia PDF Downloads 291404 Contribution of Remote Sensing and GIS to the Study of the Impact of the Salinity of Sebkhas on the Quality of Groundwater: Case of Sebkhet Halk El Menjel (Sousse)
Authors: Gannouni Sonia, Hammami Asma, Saidi Salwa, Rebai Noamen
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Water resources in Tunisia have experienced quantitative and qualitative degradation, especially when talking about wetlands and Sbekhas. Indeed, the objective of this work is to study the spatio-temporal evolution of salinity for 29 years (from 1987 to 2016). A study of the connection between surface water and groundwater is necessary to know the degree of influence of the Sebkha brines on the water table. The evolution of surface salinity is determined by remote sensing based on Landsat TM and OLI/TIRS satellite images of the years 1987, 2007, 2010, and 2016. The processing of these images allowed us to determine the NDVI(Normalized Difference Vegetation Index), the salinity index, and the surface temperature around Sebkha. In addition, through a geographic information system(GIS), we could establish a map of the distribution of salinity in the subsurface of the water table of Chott Mariem and Hergla/SidiBouAli/Kondar. The results of image processing and the calculation of the index and surface temperature show an increase in salinity downstream of in addition to the sebkha and the development of vegetation cover upstream and the western part of the sebkha. This richness may be due both to contamination by seawater infiltration from the barrier beach of Hergla as well as the passage of groundwater to the sebkha.Keywords: spatio-temporal monitoring, salinity, satellite images, NDVI, sebkha
Procedia PDF Downloads 133403 Optimal Dynamic Regime for CO Oxidation Reaction Discovered by Policy-Gradient Reinforcement Learning Algorithm
Authors: Lifar M. S., Tereshchenko A. A., Bulgakov A. N., Guda S. A., Guda A. A., Soldatov A. V.
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Metal nanoparticles are widely used as heterogeneous catalysts to activate adsorbed molecules and reduce the energy barrier of the reaction. Reaction product yield depends on the interplay between elementary processes - adsorption, activation, reaction, and desorption. These processes, in turn, depend on the inlet feed concentrations, temperature, and pressure. At stationary conditions, the active surface sites may be poisoned by reaction byproducts or blocked by thermodynamically adsorbed gaseous reagents. Thus, the yield of reaction products can significantly drop. On the contrary, the dynamic control accounts for the changes in the surface properties and adjusts reaction parameters accordingly. Therefore dynamic control may be more efficient than stationary control. In this work, a reinforcement learning algorithm has been applied to control the simulation of CO oxidation on a catalyst. The policy gradient algorithm is learned to maximize the CO₂ production rate based on the CO and O₂ flows at a given time step. Nonstationary solutions were found for the regime with surface deactivation. The maximal product yield was achieved for periodic variations of the gas flows, ensuring a balance between available adsorption sites and the concentration of activated intermediates. This methodology opens a perspective for the optimization of catalytic reactions under nonstationary conditions.Keywords: artificial intelligence, catalyst, co oxidation, reinforcement learning, dynamic control
Procedia PDF Downloads 131402 Suspended Nickel Oxide Nano-Beam and Its Heterostructure Device for Gas Sensing
Authors: Kusuma Urs M. B., Navakant Bhat, Vinayak B. Kamble
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Metal oxide semiconductors (MOS) are known to be excellent candidates for solid-state gas sensor devices. However, in spite of high sensitivities, their high operating temperatures and lack of selectivity is a big concern limiting their practical applications. A lot of research has been devoted so far to enhance their sensitivity and selectivity, often empirically. Some of the promising routes to achieve the same are reducing dimensionality and formation of heterostructures. These heterostructures offer improved sensitivity, selectivity even at relatively low operating temperatures compared to bare metal oxides. Thus, a combination of n-type and p-type metal oxides leads to the formation of p-n junction at the interface resulting in the diffusion of the carriers across the barrier along with the surface adsorption. In order to achieve this and to study their sensing mechanism, we have designed and lithographically fabricated a suspended nanobeam of NiO, which is a p-type semiconductor. The response of the same has been studied for various gases and is found to exhibit selective response towards hydrogen gas at room temperature. Further, the same has been radially coated with TiO₂ shell of varying thicknesses, in order to study the effect of radial p-n junction thus formed. Subsequently, efforts have been made to study the effect of shell thickness on the space charge region and to shed some light on the basic mechanism involved in gas sensing of MOS sensors.Keywords: gas sensing, heterostructure, metal oxide semiconductor, space charge region
Procedia PDF Downloads 132401 Insights and Inferences Associated with Subscription of Health Insurance in the Informal Sector of India
Authors: Harinder Singh
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The paper sheds light on the perceptions of the uninsured workers employed in the urban informal sector of India, towards the health insurance. In addition to this, it also explores the association of the identified perceptions with household decisions to enroll for health insurance schemes in India. Firstly the data taken from the primary survey of the uninsured workers employed in the urban informal sector was analyzed using exploratory factor analysis to evaluate the perceptions. Thereafter, logistic regression was employed to determine the association of the identified perceptions regarding the enrollment. Our study identifies twelve perceptions related to the health insurance enrollment of the uninsured workers employed in the urban informal sector of India. The study demonstrates that perceptions have the strongest association with the voluntary enrollment. These specifically relate to the lack of awareness about the need to buy health insurance; comprehensive coverage; income constraint; future contingencies and social obligations; lack of information; availability of subsidized government health care; linkage with government hospitals and preference for government schemes. Conclusions: Along with the food security, health security has become a crying need of the workers employed in the informal sector and the time has come to scale up the health insurance schemes for them in the country. Policy makers or marketers of health insurance policies should recognize the household perceptions as a potential barrier and try to develop a health insurance package as per the actual needs of the informal sector (low income) in India.Keywords: association, enrollment, health insurance, informal sector, perceptions, uninsured
Procedia PDF Downloads 270400 Recycling Motivations and Barriers in Kota Kinabalu, Malaysia
Authors: Jasmine Adela Mutang, Rosnah Ismail, Chua Bee Seok, Ferlis Bahari, Lailawati Madlan, Walton Wider, Rickless Das
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Waste projection is increasing and most landfills in Malaysia are running out of space. Due to that, waste management is now becoming a major challenge. The most sustainable solution is by practicing sustainable practices such as recycling. Since 1993 the government has launched several recycling campaigns and implemented the National Recycling Policy. However, public participation is still very low. Only 10.5% of solid waste was recycled up to now which is far below than of in developed countries. Nevertheless the government is optimistic that the target of 22% recycling by 2020 will be achieved if there is a positive flow pattern in sustainable practices in particular recycling behavior among Malaysian. Understanding public motivations towards recycling domestic waste are important to improve current recycling rate. Thus this study attempts to identify what are the possible motivations and hindrances for the public to recycle. Open-ended questions format were administered to 484 people in Kota Kinabalu, Sabah, Malaysia. Two specific questions we asked to explore their general determinants and barriers in practicing recycling: “What motivates you to recycle?” and “What are the barriers you encountered in doing recycling activities?” Thematic analysis was conducted on the open-ended questions in which themes were created with the raw comments. It was found that the underlying recycling motivations are awareness’ towards the environment, benefits to the society and individual, and social influence. Non participations are influence by attitudes, commitment, facilities, knowledge, inconvenience, and enforcement.Keywords: recycling motivation, recycling barrier, sustainable, household waste
Procedia PDF Downloads 554399 Podcasting: A Tool for an Enhanced Learning Experience of Introductory Courses to Science and Engineering Students
Authors: Yaser E. Greish, Emad F. Hindawy, Maryam S. Al Nehayan
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Introductory courses such as General Chemistry I, General Physics I and General Biology need special attention as students taking these courses are usually at their first year of the university. In addition to the language barrier for most of them, they also face other difficulties if these elementary courses are taught in the traditional way. Changing the routine method of teaching of these courses is therefore mandated. In this regard, podcasting of chemistry lectures was used as an add-on to the traditional and non-traditional methods of teaching chemistry to science and non-science students. Podcasts refer to video files that are distributed in a digital format through the Internet using personal computers or mobile devices. Pedagogical strategy is another way of identifying podcasts. Three distinct teaching approaches are evident in the current literature and include receptive viewing, problem-solving, and created video podcasts. The digital format and dispensing of video podcasts have stabilized over the past eight years, the type of podcasts vary considerably according to their purpose, degree of segmentation, pedagogical strategy, and academic focus. In this regard, the whole syllabus of 'General Chemistry I' course was developed as podcasts and were delivered to students throughout the semester. Students used the podcasted files extensively during their studies, especially as part of their preparations for exams. Feedback of students strongly supported the idea of using podcasting as it reflected its effect on the overall understanding of the subject, and a consequent improvement of their grades.Keywords: podcasting, introductory course, interactivity, flipped classroom
Procedia PDF Downloads 265398 Design of Aesthetic Acoustic Metamaterials Window Panel Based on Sierpiński Fractal Triangle for Sound-silencing with Free Airflow
Authors: Sanjeet Kumar Singh, Shanatanu Bhattacharaya
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Design of high- efficiency low, frequency (<1000Hz) soundproof window or wall absorber which is transparent to airflow is presented. Due to the massive rise in human population and modernization, environmental noise has significantly risen globally. Prolonged noise exposure can cause severe physiological and psychological symptoms like nausea, headaches, fatigue, and insomnia. There has been continuous growth in building construction and infrastructure like offices, bus stops, and airports due to urban population. Generally, a ventilated window is used for getting fresh air into the room, but at the same time, unwanted noise comes along. Researchers used traditional approaches like noise barrier mats in front of the window or designed the entire window using sound-absorbing materials. However, this solution is not aesthetically pleasing, and at the same time, it's heavy and not adequate for low-frequency noise shielding. To address this challenge, we design a transparent hexagonal panel based on Sierpiński fractal triangle, which is aesthetically pleasing, demonstrates normal incident sound absorption coefficient more than 0.96 around 700 Hz and transmission loss around 23 dB while maintaining e air circulation through triangular cutout. Next, we present a concept of fabrication of large acoustic panel for large-scale applications, which lead to suppressing the urban noise pollution.Keywords: acoustic metamaterials, noise, functional materials, ventilated
Procedia PDF Downloads 83397 Obstacles to Accessible Tourism for People with Mental, Physical and Mobility Disability: A Case Study of North Cyprus
Authors: Marjan Kamyabi
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Attending tourism in the current century is one of the key factors in the success of the tourism industry and, consequently, the prosperity of the economies of the countries. In this regard, accessible tourism can play a major role in the development of tourism, taking into account the attractions, facilities and capabilities of the development of tourism in Northern Cyprus, and given that the satisfaction of tourists from the product and destination of tourism has an undeniable role in attracting tourists. The purpose of this study is to investigate the environmental barriers and accessibility of the tourism industry in Northern Cyprus. Another goal of this study is to introduce this consumer group to the tourism community. In order to achieve the objectives of this paper, a questionnaire was designed and provided to three tourism professionals to assess the reliability, and then, among the 200 people with physical and mental disabilities who travelled to Cyprus, The data analysis was used as a confirmatory factor analysis method. The environmental barrier for tourists with disabilities is classified in three sections of transport, attractions and accommodation, each section being separately identified separately. In general, observance of the principles and standards of proper fitting in the main sectors of the tourism industry of Northern Cyprus in the situation The facilities and transportation were identified as the first problem and obstacle for the development of tourism for people with physical and mental disabilities and, finally, suggestions and solutions for the development of tourism for people with physical and physical disabilities were presented.Keywords: accessible tourism, environmental barriers, tourism, people with disability, accessibility
Procedia PDF Downloads 191396 Crops Cold Stress Alleviation by Silicon: Application on Turfgrass
Authors: Taoufik Bettaieb, Sihem Soufi
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As a bioactive metalloid, silicon (Si) is an essential element for plant growth and development. It also plays a crucial role in enhancing plants’ resilience to different abiotic and biotic stresses. The morpho-physiological, biochemical, and molecular background of Si-mediated stress tolerance in plants were unraveled. Cold stress is a severe abiotic stress response to the decrease of plant growth and yield by affecting various physiological activities in plants. Several approaches have been used to alleviate the adverse effects generated from cold stress exposure, but the cost-effective, environmentally friendly, and defensible approach is the supply of silicon. Silicon has the ability to neutralize the harmful impacts of cold stress. Therefore, based on these hypotheses, this study was designed in order to investigate the morphological and physiological background of silicon effects applied at different concentrations on cold stress mitigation during early growth of a turfgrass, namely Paspalum vaginatum Sw. Results show that silicon applied at different concentrations improved the morphological development of Paspalum subjected to cold stress. It is also effective on the photosynthetic apparatus by maintaining stability the photochemical efficiency. As the primary component of cellular membranes, lipids play a critical function in maintaining the structural integrity of plant cells. Silicon application decreased membrane lipid peroxidation and kept on membrane frontline barrier relatively stable under cold stress.Keywords: crops, cold stress, silicon, abiotic stress
Procedia PDF Downloads 123395 Enhancing Cellulose Acetate Films: Impact of Glycerol and Ionic Liquid Plasticizers
Authors: Rezzouq Asiya, Bouftou Abderrahim, Belfadil Doha, Taoufyk Azzeddine, El Bouchti Mehdi, Zyade Souad, Cherkaoui Omar, Majid Sanaa
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Plastic packaging is widely used, but its pollution is a major environmental problem. Solutions require new sustainable technologies, environmental management, and the use of bio-based polymers as sustainable packaging. Cellulose acetate (CA) is a biobased polymer used in a variety of applications such as the manufacture of plastic films, textiles, and filters. However, it has limitations in terms of thermal stability and rigidity, which necessitates the addition of plasticizers to optimize its use in packaging. Plasticizers are molecules that increase the flexibility of polymers, but their influence on the chemical and physical properties of films (CA) has not been studied in detail. Some studies have focused on mechanical and thermal properties. However, an in-depth analysis is needed to understand the interactions between the additives and the polymer matrix. In this study, the aim is to examine the effect of two types of plasticizers, glycerol (a conventional plasticizer) and an ionic liquid, on the transparency, mechanical, thermal and barrier properties of cellulose acetate (CA) films prepared by the solution-casting method . Various analytical techniques were used to characterize these films, including infrared spectroscopy (FT-IR), X-ray diffraction (XRD), thermogravimetric analysis (TGA), water vapor permeability (WVP), oxygen permeability, scanning electron microscopy (SEM), opacity, transmission analysis and mechanical tests.Keywords: cellulose acetate, plasticizers, biopolymers, ionic liquid, glycerol.
Procedia PDF Downloads 40394 Double Negative Differential Resistance Features in Series AIN/GaN Double-Barrier Resonant Tunneling Diodes Vertically Integrated by Plasma-Assisted Molecular Beam Epitaxy
Authors: Jiajia Yao, Guanlin Wu, Fang Liu, Junshuai Xue, Yue Hao
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This study reports on the epitaxial growth of a GaN-based resonant tunneling diode (RTD) structure with stable and repeatable double negative differential resistance (NDR) characteristics at room temperature on a c-plane GaN-on-sapphire template using plasma-assisted molecular beam epitaxy (PA-MBE) technology. In this structure, two independent AlN/GaN RTDs are epitaxially connected in series in the vertical growth direction through a silicon-doped GaN layer. As the collector electrode bias voltage increases, the two RTDs respectively align the ground state energy level in the quantum well with the 2DEG energy level in the emitter accumulation well to achieve quantum resonant tunneling and then reach the negative differential resistance (NDR) region. The two NDR regions exhibit similar peak current densities and peak-to-valley current ratios, which are 230 kA/cm² and 249 kA/cm², 1.33 and 1.38, respectively, for a device with a collector electrode mesa diameter of 1 µm. The consistency of the NDR is much higher than the results of on-chip discrete RTD device interconnection, resulting from the smaller chip area, fewer interconnect parasitic parameters, and less process complexity. The methods and results presented in this paper show the brilliant prospects of GaN RTDs in the development of multi-value logic digital circuits.Keywords: MBE, AlN/GaN, RTDs, double NDR
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