Search results for: enhanced swelling and mechanical strength
1337 Combined Effect of Vesicular System and Iontophoresis on Skin Permeation Enhancement of an Analgesic Drug
Authors: Jigar N. Shah, Hiral J. Shah, Praful D. Bharadia
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The major challenge faced by formulation scientists in transdermal drug delivery system is to overcome the inherent barriers related to skin permeation. The stratum corneum layer of the skin is working as the rate limiting step in transdermal transport and reduce drug permeation through skin. Many approaches have been used to enhance the penetration of drugs through this layer of the skin. The purpose of this study is to investigate the development and evaluation of a combined approach of drug carriers and iontophoresis as a vehicle to improve skin permeation of an analgesic drug. Iontophoresis is a non-invasive technique for transporting charged molecules into and through tissues by a mild electric field. It has been shown to effectively deliver a variety of drugs across the skin to the underlying tissue. In addition to the enhanced continuous transport, iontophoresis allows dose titration by adjusting the electric field, which makes personalized dosing feasible. Drug carrier could modify the physicochemical properties of the encapsulated molecule and offer a means to facilitate the percutaneous delivery of difficult-to-uptake substances. Recently, there are some reports about using liposomes, microemulsions and polymeric nanoparticles as vehicles for iontophoretic drug delivery. Niosomes, the nonionic surfactant-based vesicles that are essentially similar in properties to liposomes have been proposed as an alternative to liposomes. Niosomes are more stable and free from other shortcoming of liposomes. Recently, the transdermal delivery of certain drugs using niosomes has been envisaged and niosomes have proved to be superior transdermal nanocarriers. Proniosomes overcome some of the physical stability related problems of niosomes. The proniosomal structure was liquid crystalline-compact niosomes hybrid which could be converted into niosomes upon hydration. The combined use of drug carriers and iontophoresis could offer many additional benefits. The system was evaluated for Encapsulation Efficiency, vesicle size, zeta potential, Transmission Electron Microscopy (TEM), DSC, in-vitro release, ex-vivo permeation across skin and rate of hydration. The use of proniosomal gel as a vehicle for the transdermal iontophoretic delivery was evaluated in-vitro. The characteristics of the applied electric current, such as density, type, frequency, and on/off interval ratio were observed. The study confirms the synergistic effect of proniosomes and iontophoresis in improving the transdermal permeation profile of selected analgesic drug. It is concluded that proniosomal gel can be used as a vehicle for transdermal iontophoretic drug delivery under suitable electric conditions.Keywords: iontophoresis, niosomes, permeation enhancement, transdermal delivery
Procedia PDF Downloads 3791336 Carbon Sequestration in Spatio-Temporal Vegetation Dynamics
Authors: Nothando Gwazani, K. R. Marembo
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An increase in the atmospheric concentration of carbon dioxide (CO₂) from fossil fuel and land use change necessitates identification of strategies for mitigating threats associated with global warming. Oceans are insufficient to offset the accelerating rate of carbon emission. However, the challenges of oceans as a source of reducing carbon footprint can be effectively overcome by the storage of carbon in terrestrial carbon sinks. The gases with special optical properties that are responsible for climate warming include carbon dioxide (CO₂), water vapors, methane (CH₄), nitrous oxide (N₂O), nitrogen oxides (NOₓ), stratospheric ozone (O₃), carbon monoxide (CO) and chlorofluorocarbons (CFC’s). Amongst these, CO₂ plays a crucial role as it contributes to 50% of the total greenhouse effect and has been linked to climate change. Because plants act as carbon sinks, interest in terrestrial carbon sequestration has increased in an effort to explore opportunities for climate change mitigation. Removal of carbon from the atmosphere is a topical issue that addresses one important aspect of an overall strategy for carbon management namely to help mitigate the increasing emissions of CO₂. Thus, terrestrial ecosystems have gained importance for their potential to sequester carbon and reduce carbon sink in oceans, which have a substantial impact on the ocean species. Field data and electromagnetic spectrum bands were analyzed using ArcGIS 10.2, QGIS 2.8 and ERDAS IMAGINE 2015 to examine the vegetation distribution. Satellite remote sensing data coupled with Normalized Difference Vegetation Index (NDVI) was employed to assess future potential changes in vegetation distributions in Eastern Cape Province of South Africa. The observed 5-year interval analysis examines the amount of carbon absorbed using vegetation distribution. In 2015, the numerical results showed low vegetation distribution, therefore increased the acidity of the oceans and gravely affected fish species and corals. The outcomes suggest that the study area could be effectively utilized for carbon sequestration so as to mitigate ocean acidification. The vegetation changes measured through this investigation suggest an environmental shift and reduced vegetation carbon sink, and that threatens biodiversity and ecosystem. In order to sustain the amount of carbon in the terrestrial ecosystems, the identified ecological factors should be enhanced through the application of good land and forest management practices. This will increase the carbon stock of terrestrial ecosystems thereby reducing direct loss to the atmosphere.Keywords: remote sensing, vegetation dynamics, carbon sequestration, terrestrial carbon sink
Procedia PDF Downloads 1511335 Well-Defined Polypeptides: Synthesis and Selective Attachment of Poly(ethylene glycol) Functionalities
Authors: Cristina Lavilla, Andreas Heise
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The synthesis of sequence-controlled polymers has received increasing attention in the last years. Well-defined polyacrylates, polyacrylamides and styrene-maleimide copolymers have been synthesized by sequential or kinetic addition of comonomers. However this approach has not yet been introduced to the synthesis of polypeptides, which are in fact polymers developed by nature in a sequence-controlled way. Polypeptides are natural materials that possess the ability to self-assemble into complex and highly ordered structures. Their folding and properties arise from precisely controlled sequences and compositions in their constituent amino acid monomers. So far, solid-phase peptide synthesis is the only technique that allows preparing short peptide sequences with excellent sequence control, but also requires extensive protection/deprotection steps and it is a difficult technique to scale-up. A new strategy towards sequence control in the synthesis of polypeptides is introduced, based on the sequential addition of α-amino acid-N-carboxyanhydrides (NCAs). The living ring-opening process is conducted to full conversion and no purification or deprotection is needed before addition of a new amino acid. The length of every block is predefined by the NCA:initiator ratio in every step. This method yields polypeptides with a specific sequence and controlled molecular weights. A series of polypeptides with varying block sequences have been synthesized with the aim to identify structure-property relationships. All of them are able to adopt secondary structures similar to natural polypeptides, and display properties in the solid state and in solution that are characteristic of the primary structure. By design the prepared polypeptides allow selective modification of individual block sequences, which has been exploited to introduce functionalities in defined positions along the polypeptide chain. Poly(ethylene glycol)(PEG) was the functionality chosen, as it is known to favor hydrophilicity and also yield thermoresponsive materials. After PEGylation, hydrophilicity of the polypeptides is enhanced, and their thermal response in H2O has been studied. Noteworthy differences in the behavior of the polypeptides having different sequences have been found. Circular dichroism measurements confirmed that the α-helical conformation is stable over the examined temperature range (5-90 °C). It is concluded that PEG units are the main responsible of the changes in H-bonding interactions with H2O upon variation of temperature, and the position of these functional units along the backbone is a factor of utmost importance in the resulting properties of the α-helical polypeptides.Keywords: α-amino acid N-carboxyanhydrides, multiblock copolymers, poly(ethylene glycol), polypeptides, ring-opening polymerization, sequence control
Procedia PDF Downloads 2001334 Metabolic Syndrome and Its Effects on Cartilage Degeneration vs Regeneration: A Pilot Study Using Osteoarthritis Biomarkers
Authors: Neena Kanojia, R. K. Kanojia
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Background: Osteoarthritis OA of the knee is one of the leading causes of disability characterized by degeneration of hyaline cartilage combined with reparative processes. Its strong association with metabolic syndrome is postulated to be due to both mechanical and biochemical factors. Our study aims to study differential effect of metabolic risk factors on cartilage degeneration and regeneration at biomarker level. Design: After screening 281 patients presenting with knee pain, 41 patients who met the selection criteria were included and were divided into metabolic MetS OA and non-metabolic Non-MetS OA phenotypes using National Cholesterol Education Programme-Adult Treatment Panel-III NCEP ATP III criteria for metabolic syndrome. Serum Cartilage Oligomeric Matrix Protein COMP and Procollagen type IIA N terminal Propeptide PIIANP levels were used as tools to assess cartilage degeneration and regeneration, respectively. Results: 22 among 41 patients 53.66% had metabolic syndrome. Covariates like age, gender, Kellgren Lawrence KL grades were comparable in both groups. MetS OA group showed significant increase in serum COMP levels (p 0.03 with no significant effect on serum PIIANP levels (p 0.46. Hypertriglyceridemia showed independent association with both cartilage anabolism (p 0.03 and catabolism (p 0.03. Conclusion: Metabolic syndrome, though has no effect on cartilage regeneration tends to shift cartilage homeostasis towards degeneration with hypertriglyceridemia showing significant independent effect on cartilage metabolism.Keywords: metabolic, syndrome, cartilage, degernation
Procedia PDF Downloads 651333 Geometric, Energetic and Topological Analysis of (Ethanol)₉-Water Heterodecamers
Authors: Jennifer Cuellar, Angie L. Parada, Kevin N. S. Chacon, Sol M. Mejia
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The purification of bio-ethanol through distillation methods is an unresolved issue at the biofuel industry because of the ethanol-water azeotrope formation, which increases the steps of the purification process and subsequently increases the production costs. Therefore, understanding the mixture nature at the molecular level could provide new insights for improving the current methods and/or designing new and more efficient purification methods. For that reason, the present study focuses on the evaluation and analysis of (ethanol)₉-water heterodecamers, as the systems with the minimum molecular proportion that represents the azeotropic concentration (96 %m/m in ethanol). The computational modelling was carried out with B3LYP-D3/6-311++G(d,p) in Gaussian 09. Initial explorations of the potential energy surface were done through two methods: annealing simulated runs and molecular dynamics trajectories besides intuitive structures obtained from smaller (ethanol)n-water heteroclusters, n = 7, 8 and 9. The energetic order of the seven stable heterodecamers determines the most stable heterodecamer (Hdec-1) as a structure forming a bicyclic geometry with the O-H---O hydrogen bonds (HBs) where the water is a double proton donor molecule. Hdec-1 combines 1 water molecule and the same quantity of every ethanol conformer; this is, 3 trans, 3 gauche 1 and 3 gauche 2; its abundance is 89%, its decamerization energy is -80.4 kcal/mol, i.e. 13 kcal/mol most stable than the less stable heterodecamer. Besides, a way to understand why methanol does not form an azeotropic mixture with water, analogous systems ((ethanol)10, (methanol)10, and (methanol)9-water)) were optimized. Topologic analysis of the electron density reveals that Hec-1 forms 33 weak interactions in total: 11 O-H---O, 8 C-H---O, 2 C-H---C hydrogen bonds and 12 H---H interactions. The strength and abundance of the most unconventional interactions (H---H, C-H---O and C-H---O) seem to explain the preference of the ethanol for forming heteroclusters instead of clusters. Besides, O-H---O HBs present a significant covalent character according to topologic parameters as the Laplacian of electron density and the relationship between potential and kinetic energy densities evaluated at the bond critical points; obtaining negatives values and values between 1 and 2, for those two topological parameters, respectively.Keywords: ADMP, DFT, ethanol-water azeotrope, Grimme dispersion correction, simulated annealing, weak interactions
Procedia PDF Downloads 1031332 The Correlation between Head of Bed Angle and IntraAbdominal Pressure of Intubated Patients; a Pre-Post Clinical Trial
Authors: Sedigheh Samimian, Sadra Ashrafi, Tahereh Khaleghdoost Mohammadi, Mohammad Reza Yeganeh, Ali Ashraf, Hamideh Hakimi, Maryam Dehghani
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Introduction: The recommended position for measuring Intra-Abdominal Pressure (IAP) is the supine position. However, patients put in this position are prone to Ventilator-associated pneumonia. This study was done to evaluate the relationship between bed head angle and IAP measurements of intubated patients in the intensive care unit. Methods: In this clinical trial, seventy-six critically ill patients under mechanical ventilation were enrolled. IAP measurement was performed every 8 hours for 24 hours using the KORN method in three different degrees of the head of bed (HOB) elevation (0°, 15°, and 30°). Bland-Altman analysis was performed to identify the bias and limits of agreement among the three HOBs. According to World Society of the Abdominal Compartment Syndrome (WSACS), we can consider two IAP techniques equivalent if a bias of <1 mmHg and limits of agreement of - 4 to +4 were found between them. Data were analyzed using SPSS statistical software (v. 19), and the significance level was considered as 0.05. Results: The prevalence of intra-abdominal hypertension was 18.42%. Mean ± standard deviation (SD) of IAP were 8.44 ± 4.02 mmHg for HOB angle 0°, 9.58 ± 4.52 for HOB angle 15°, and 11.10 ± 4.73 for HOB angle 30o (p = 0.0001). The IAP measurement bias between HOB angle 0◦ and HOB angle 15° was 1.13 mmHg. This bias was 2.66 mmHg between HOB angle 0° and HOB angle 30°. Conclusion: Elevation of HOB angle from 0 to 30 degree significantly increases IAP. It seems that the measurement of IAP at HOB angle 15° was more reliable than 30°.Keywords: pressure, intra-abdominal hypertension, head of bed, critical care, compartment syndrome, supine position
Procedia PDF Downloads 701331 Design and Analysis of a Planetary Gearbox Used in Stirred Vessel
Authors: Payal T. Patel, Ramakant Panchal, Ketankumar G. Patel
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Gear in stirred vessel is one of the most critical components in machinery which has power transmission system and it is rotating machinery cost and redesign being the major constraints, there is always a great scope for a mechanical engineer to apply skills to improve the design. Gear will be most effective means of transmitting power in future machinery due to their high degree of compactness. The Galliard moved in the industry from heavy industries such as textile machinery and shipbuilding to industries such as automobile manufacture tools will necessitate the affable application of gear technology. The two-stage planetary reduction gear unit is designed to meet the output specifications. In industries, where the bevel gears are used in turret vessel to transmit the power, that unit is replaced by this planetary gearbox. Use of this type of gearbox is to get better efficiency and also the manufacturing of the bevel gear is more complex than the spur gears. Design a gearbox with the epicyclic gear train. In industries, the power transmission from gearbox to vessel is done through the bevel gears, which transmit the power at a right angle. In this work, the power is to be transmitted vertically from gearbox to vessel, which will increase the efficiency and life of gears. The arrangement of the gears is quite difficult as well as it needs high manufacturing cost and maintenance cost. The design is replaced by the planetary gearbox to reduce the difficulties, and same output is achieved but with a different arrangement of the planetary gearbox.Keywords: planetary gearbox, epicyclic gear, optimization, dynamic balancing
Procedia PDF Downloads 3591330 D-Lysine Assisted 1-Ethyl-3-(3-Dimethylaminopropyl)Carbodiimide / N-Hydroxy Succinimide Initiated Crosslinked Collagen Scaffold with Controlled Structural and Surface Properties
Authors: G. Krishnamoorthy, S. Anandhakumar
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The effect of D-Lysine (D-Lys) on collagen with 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide(EDC)/N-hydroxysuccinimide(NHS) initiated cross linking using experimental and modelling tools are evaluated. The results of the Coll-D-Lys-EDC/NHS scaffold also indicate an increase in the tensile strength (TS), percentage of elongation (% E), denaturation temperature (Td), and decrease the decomposition rate compared to L-Lys-EDC/NHS. Scanning electron microscopic (SEM) and atomic force microscopic (AFM) analyses revealed a well ordered with properly oriented and well-aligned structure of scaffold. The D-Lys stabilizes the scaffold against degradation by collagenase than L-Lys. The cell assay showed more than 98% fibroblast viability (NIH3T3) and improved cell adhesions, protein adsorption after 72h of culture when compared with native scaffold. Cell attachment after 74h was robust, with cytoskeletal analysis showing that the attached cells were aligned along the fibers assuming a spindle-shape appearance, despite, gene expression analyses revealed no apparent alterations in mRNA levels, although cell proliferation was not adversely affected. D-Lysine (D-Lys) plays a pivotal role in the self-assembly and conformation of collagen fibrils. The D-Lys assisted EDC/NHS initiated cross-linking induces the formation of an carboxamide by the activation of the side chain -COOH group, followed by aminolysis of the O-iso acylurea intermediates by the -NH2 groups are directly joined via an isopeptides bond. This leads to the formation of intra- and inter-helical cross links. Modeling studies indicated that D-Lys bind with collagen-like peptide (CLP) through multiple H-bonding and hydrophobic interactions. Orientational changes in collagenase on CLP-D-Lys are observed which may decrease its accessibility to degradation and stabilize CLP against the action of the former. D-Lys has lowest binding energy and improved fibrillar-assembly and staggered alignment without the undesired structural stiffness and aggregations. The proteolytic machinery is not well equipped to deal with Coll-D-Lys than Coll-L-Lys scaffold. The information derived from the present study could help in designing collagenolytically stable heterochiral collagen based scaffold for biomedical applications.Keywords: collagen, collagenase, collagen like peptide, D-lysine, heterochiral collagen scaffold
Procedia PDF Downloads 3911329 A Concept to Assess the Economic Importance of the On-Site Activities of ETICS
Authors: V. Sulakatko, F. U. Vogdt, I. Lill
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Construction technology and on-site construction activities have a direct influence on the life cycle costs of energy efficiently renovated apartment buildings. The systematic inadequacies of the External Thermal Insulation Composite System (ETICS) which occur during the construction phase increase the risk for all stakeholders, reduce mechanical durability and increase the life cycle costs of the building. The economic effect of these shortcomings can be minimised if the risk of the most significant on-site activities is recognised. The objective of the presented ETICS economic assessment concept is to evaluate the economic influence of on-site shortcomings and reveal their significance to the foreseeable future repair costs. The model assembles repair techniques, discusses their direct cost calculation methods, argues over the proper usage of net present value over the life cycle of the building, and proposes a simulation tool to evaluate the risk of on-site activities. As the technique is dependent on the selected real interest rate, a sensitivity analysis is anticipated to determine the validity of the recommendations. After the verification of the model on the sample buildings by the industry, it is expected to increase economic rationality of resource allocation and reduce high-risk systematic shortcomings during the construction process of ETICS.Keywords: activity-based cost estimating, cost estimation, ETICS, life cycle costing
Procedia PDF Downloads 2961328 A Finite Element Based Predictive Stone Lofting Simulation Methodology for Automotive Vehicles
Authors: Gaurav Bisht, Rahul Rathnakumar, Ravikumar Duggirala
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Predictive simulations are one of the key focus areas in safety-critical industries such as aerospace and high-performance automotive engineering. The stone-chipping study is one such effort taken up by the industry to predict and evaluate the damage caused due to gravel impact on vehicles. This paper describes a finite elements based method that can simulate the ejection of gravel chips from a vehicle tire. The FE simulations were used to obtain the initial ejection velocity of the stones for various driving conditions using a computational contact mechanics approach. To verify the accuracy of the tire model, several parametric studies were conducted. The FE simulations resulted in stone loft velocities ranging from 0–8 m/s, regardless of tire speed. The stress on the tire at the instant of initial contact with the stone increased linearly with vehicle speed. Mesh convergence studies indicated that a highly resolved tire mesh tends to result in better momentum transfer between the tire and the stone. A fine tire mesh also showed a linearly increasing relationship between the tire forward speed and stone lofting speed, which was not observed in coarser meshes. However, it also highlighted a potential challenge, in that the ejection velocity vector of the stone seemed to be sensitive to the mesh, owing to the FE-based contact mechanical formulation of the problem.Keywords: abaqus, contact mechanics, foreign object debris, stone chipping
Procedia PDF Downloads 2631327 Power Ultrasound Application on Convective Drying of Banana (Musa paradisiaca), Mango (Mangifera indica L.) and Guava (Psidium guajava L.)
Authors: Erika K. Méndez, Carlos E. Orrego, Diana L. Manrique, Juan D. Gonzalez, Doménica Vallejo
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High moisture content in fruits generates post-harvest problems such as mechanical, biochemical, microbial and physical losses. Dehydration, which is based on the reduction of water activity of the fruit, is a common option for overcoming such losses. However, regular hot air drying could affect negatively the quality properties of the fruit due to the long residence time at high temperature. Power ultrasound (US) application during the convective drying has been used as a novel method able to enhance drying rate and, consequently, to decrease drying time. In the present study, a new approach was tested to evaluate the effect of US on the drying time, the final antioxidant activity (AA) and the total polyphenol content (TPC) of banana slices (BS), mango slices (MS) and guava slices (GS). There were also studied the drying kinetics with nine different models from which water effective diffusivities (Deff) (with or without shrinkage corrections) were calculated. Compared with the corresponding control tests, US assisted drying for fruit slices showed reductions in drying time between 16.23 and 30.19%, 11.34 and 32.73%, and 19.25 and 47.51% for the MS, BS and GS respectively. Considering shrinkage effects, Deff calculated values ranged from 1.67*10-10 to 3.18*10-10 m2/s, 3.96*10-10 and 5.57*10-10 m2/s and 4.61*10-10 to 8.16*10-10 m2/s for the BS, MS and GS samples respectively. Reductions of TPC and AA (as DPPH) were observed compared with the original content in fresh fruit data in all kinds of drying assays.Keywords: banana, drying, effective diffusivity, guava, mango, ultrasound
Procedia PDF Downloads 5351326 Nuclear Materials and Nuclear Security in India: A Brief Overview
Authors: Debalina Ghoshal
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Nuclear security is the ‘prevention and detection of, and response to unauthorised removal, sabotage, unauthorised access, illegal transfer or other malicious acts involving nuclear or radiological material or their associated facilities.’ Ever since the end of Cold War, nuclear materials security has remained a concern for global security. However, with the increase in terrorist attacks not just in India especially, security of nuclear materials remains a priority. Therefore, India has made continued efforts to tighten its security on nuclear materials to prevent nuclear theft and radiological terrorism. Nuclear security is different from nuclear safety. Physical security is also a serious concern and India had been careful of the physical security of its nuclear materials. This is more so important since India is expanding its nuclear power capability to generate electricity for economic development. As India targets 60,000 MW of electricity production by 2030, it has a range of reactors to help it achieve its goal. These include indigenous Pressurised Heavy Water Reactors, now standardized at 700 MW per reactor Light Water Reactors, and the indigenous Fast Breeder Reactors that can generate more fuel for the future and enable the country to utilise its abundant thorium resource. Nuclear materials security can be enhanced through two important ways. One is through proliferation resistant technologies and diplomatic efforts to take non proliferation initiatives. The other is by developing technical means to prevent any leakage in nuclear materials in the hands of asymmetric organisations. New Delhi has already implemented IAEA Safeguards on their civilian nuclear installations. Moreover, the IAEA Additional Protocol has also been ratified by India in order to enhance its transparency of nuclear material and strengthen nuclear security. India is a party to the IAEA Conventions on Nuclear Safety and Security, and in particular the 1980 Convention on the Physical Protection of Nuclear Material and its amendment in 2005, Code of Conduct in Safety and Security of Radioactive Sources, 2006 which enables the country to provide for the highest international standards on nuclear and radiological safety and security. India's nuclear security approach is driven by five key components: Governance, Nuclear Security Practice and Culture, Institutions, Technology and International Cooperation. However, there is still scope for further improvements to strengthen nuclear materials and nuclear security. The NTI Report, ‘India’s improvement reflects its first contribution to the IAEA Nuclear Security Fund etc. in the future, India’s nuclear materials security conditions could be further improved by strengthening its laws and regulations for security and control of materials, particularly for control and accounting of materials, mitigating the insider threat, and for the physical security of materials during transport. India’s nuclear materials security conditions also remain adversely affected due to its continued increase in its quantities of nuclear material, and high levels of corruption among public officials.’ This paper would study briefly the progress made by India in nuclear and nuclear material security and the step ahead for India to further strengthen this.Keywords: India, nuclear security, nuclear materials, non proliferation
Procedia PDF Downloads 3521325 Wind Turbines Optimization: Shield Structure for a High Wind Speed Conditions
Authors: Daniyar Seitenov, Nazim Mir-Nasiri
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Optimization of horizontal axis semi-exposed wind turbine has been performed using a shield protection that automatically protects the generator shaft at extreme wind speeds from over speeding, mechanical damage and continues generating electricity during the high wind speed conditions. A semi-exposed to wind generator has been designed and its structure has been described in this paper. The simplified point-force dynamic load model on the blades has been derived for normal and extreme wind conditions with and without shield involvement. Numerical simulation has been conducted at different values of wind speed to study the efficiency of shield application. The obtained results show that the maximum power generated by the wind turbine with shield does not exceed approximately the rated value of the generator, where shield serves as an automatic break for extreme wind speed values of 15 m/sec and above. Meantime the wind turbine without shield produced a power that is much larger than the rated value. The optimized horizontal axis semi-exposed wind turbine with shield protection is suitable for low and medium power generation when installed on the roofs of high rise buildings for harvesting wind energy. Wind shield works automatically with no power consumption. The structure of the generator with the protection, math simulation of kinematics and dynamics of power generation has been described in details in this paper.Keywords: renewable energy, wind turbine, wind turbine optimization, high wind speed
Procedia PDF Downloads 1791324 The Liminal Performances of Female-Led (Sufi) Rituals: An Anthropological in Pakistan
Authors: Sana Iqbal
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The female voice in Sufi poetry has been studied as a symbol of humility and devotion. Throughout the centuries, the Sufi shrines have also sheltered women and have served as a source of emotional strength in times of difficulty. Although women have been central to Sufi Islam, female-led rituals and performances (of veneration) are rarely studied as acts of empowerment and symbols of healing. This is especially true for rituals performed in informal spaces, which require going beyond the shrine practices. The rituals and meanings associated with Khizr Khwaja (or Sindhi Hindu god Jhelelal) among women in Punjab can serve as a useful case study to unpack some of these meanings. The paper aims to shed light on female-led rituals among women from Punjab associated with the folkloric traditions associated with Khizar Khwaja, Zinda Pir, Jhulelal or river god in the South Asian region to protect mariners from possible risks (since trade was primarily dependent on water channels) or for inducing timely rain date back to the 10th century in Sindh. However, these meanings and associations have evolved and the paper thus aims to establish a relationship between this figure and the women in Punjab by analysing the findings from an ethnographic study. It traces the historical meanings and significance attached to the divine figure and the wells (informal spaces) associated with him since the rituals performed by women is now infused solely with seeking fertility or to be blessed with a successful pregnancy, as opposed to him being celebrated for other reasons in older times. These associations beg the question of what women gain out of these rituals and making offerings to the mysterious figure of Khizr. Anecdotal evidence in the form of interviews conducted in Bhakar and Talwandi (Punjab) during the summer of 2015 helped to explore the stories related to this legend while also allowing us to witness some of the female-led ritual practices. It can be said that the symbols adopted in the ritual practices invoke liminality for women, which is a blend of opposites. The paper argues that this liminality/journey has been used as a vehicle to transcend all worldly structures of power and it symbolically emphasises the richness of feminine love/devotion and grants healing to female devotees.Keywords: transgression, gender, liminality, ritual
Procedia PDF Downloads 1251323 In Vivo Evaluation of Exposure to Electromagnetic Fields at 27 GHz (5G) of Danio Rerio: A Preliminary Study
Authors: Elena Maria Scalisi, Roberta Pecoraro, Martina Contino, Sara Ignoto, Carmelo Iaria, Santi Concetto Pavone, Gino Sorbello, Loreto Di Donato, Maria Violetta Brundo
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5G Technology is evolving to satisfy a variety of service requirements that may allow high data-rate connections (1Gbps) and lower latency times than current (<1ms). In order to support a high data transmission speed and a high traffic service for eMBB (enhanced mobile broadband) use cases, 5G systems have the characteristic of using different frequency bands of the radio wave spectrum (700 MHz, 3.6-3.8 GHz and 26.5-27.5 GHz), thus taking advantage of higher frequencies than previous mobile radio generations (1G-4G). However, waves at higher frequencies have a lower capacity to propagate in free space and therefore, in order to guarantee the capillary coverage of the territory for high reliability applications, it will be necessary to install a large number of repeaters. Following the introduction of this new technology, there has been growing concern over the past few months about possible harmful effects on human health. The aim of this preliminary study is to evaluate possible short term effects induced by 5G-millimeter waves on embryonic development and early life stages of Danio rerio by Z-FET. We exposed developing zebrafish at frequency of 27 GHz, with a standard pyramidal horn antenna placed at 15 cm far from the samples holder ensuring an incident power density of 10 mW/cm2. During the exposure cycle, from 6 h post fertilization (hpf) to 96 hpf, we measured a different morphological endpoints every 24 hours. Zebrafish embryo toxicity test (Z-FET) is a short term test, carried out on fertilized eggs of zebrafish and it represents an effective alternative to acute test with adult fish (OECD, 2013). We have observed that 5G did not reveal significant impacts on mortality nor on morphology because exposed larvae showed a normal detachment of the tail, presence of heartbeat, well-organized somites, therefore hatching rate was lower than untreated larvae even at 48 h of exposure. Moreover, the immunohistochemical analysis performed on larvae showed a negativity to the HSP-70 expression used as a biomarkers. This is a preliminary study on evaluation of potential toxicity induced by 5G and it seems appropriate to underline the importance that further studies would take, aimed at clarifying the probable real risk of exposure to electromagnetic fields.Keywords: Biomarker of exposure, embryonic development, 5G waves, zebrafish embryo toxicity test
Procedia PDF Downloads 1291322 Fabrication and Characterization of Al2O3 Based Electrical Insulation Coatings Around SiC Fibers
Authors: S. Palaniyappan, P. K. Chennam, M. Trautmann, H. Ahmad, T. Mehner, T. Lampke, G. Wagner
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In structural-health monitoring of fiber reinforced plastics (FRPs), every single inorganic fiber sensor that are integrated into the bulk material requires an electrical insulation around itself, when the surrounding reinforcing fibers are electrically conductive. This results in a more accurate data acquisition only from the sensor fiber without any electrical interventions. For this purpose, thin nano-films of aluminium oxide (Al2O3)-based electrical-insulation coatings have been fabricated around the Silicon Carbide (SiC) single fiber sensors through reactive DC magnetron sputtering technique. The sputtered coatings were amorphous in nature and the thickness of the coatings increased with an increase in the sputter time. Microstructural characterization of the coated fibers performed using scanning electron microscopy (SEM) confirmed a homogeneous circumferential coating with no detectable defects or cracks on the surface. X-ray diffraction (XRD) analyses of the as-sputtered and 2 hours annealed coatings (825 & 1125 ˚C) revealed the amorphous and crystalline phases of Al2O3 respectively. Raman spectroscopic analyses produced no characteristic bands of Al2O3, as the thickness of the films was in the nanometer (nm) range, which is too small to overcome the actual penetration depth of the laser used. In addition, the influence of the insulation coatings on the mechanical properties of the SiC sensor fibers has been analyzed.Keywords: Al₂O₃ thin film, electrical insulation coating, PVD process, SiC fibre, single fibre tensile test
Procedia PDF Downloads 1231321 Development and Performance Evaluation of a Gladiolus Planter in Field for Planting Corms
Authors: T. P. Singh, Vijay Gautam
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Gladiolus is an important cash crop and is grown mainly for its elegant spikes. Traditionally the gladiolus corms are planted manually which is very tedious, time consuming and labor intensive operation. So far, there is no planter available for planting of gladiolus corms. With a view to mechanize the planting operation of this horticultural crop, a prototype of 4-row gladiolus planter was developed and its performance was evaluated in-situ condition. Cup-chain type metering device was used to singulate the gladiolus corms while planting. Three levels of corm spacing viz 15, 20 and 25 cm and four levels of forward speed viz 1.0, 1.5, 2.0 and 2.5 km/h was taken as evaluation parameter for the planter. The performance indicators namely corm spacing in each row, coefficient of uniformity, missing index, multiple index, quality of feed index, number of corms per meter length, mechanical damage to the corms etc. were determined during the field test. The data was statistically analyzed using Completely Randomized Design (CRD) for testing the significance of the parameters. The result indicated that planter was able to drop the corms at required nominal spacing with minor variations. The highest deviation from the mean corm spacing was observed as 3.53 cm with maximum coefficient of variation as 13.88%. The highest missing and quality of feed indexes were observed as 6.33% and 97.45% respectively with no multiples. The performance of the planter was observed better at lower forward speed and wider corm spacing. The field capacity of the planter was found as 0.103 ha/h with an observed field efficiency of 76.57%.Keywords: coefficient of uniformity, corm spacing, gladiolus planter, mechanization
Procedia PDF Downloads 2391320 Cross-Comparison between Land Surface Temperature from Polar and Geostationary Satellite over Heterogenous Landscape: A Case Study in Hong Kong
Authors: Ibrahim A. Adeniran, Rui F. Zhu, Man S. Wong
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Owing to the insufficiency in the spatial representativeness and continuity of in situ temperature measurements from weather stations (WS), the use of temperature measurement from WS for large-range diurnal analysis in heterogenous landscapes has been limited. This has made the accurate estimation of land surface temperature (LST) from remotely sensed data more crucial. Moreover, the study of dynamic interaction between the atmosphere and the physical surface of the Earth could be enhanced at both annual and diurnal scales by using optimal LST data derived from satellite sensors. The tradeoff between the spatial and temporal resolution of LSTs from satellite’s thermal infrared sensors (TIRS) has, however, been a major challenge, especially when high spatiotemporal LST data are recommended. It is well-known from existing literature that polar satellites have the advantage of high spatial resolution, while geostationary satellites have a high temporal resolution. Hence, this study is aimed at designing a framework for the cross-comparison of LST data from polar and geostationary satellites in a heterogeneous landscape. This could help to understand the relationship between the LST estimates from the two satellites and, consequently, their integration in diurnal LST analysis. Landsat-8 satellite data will be used as the representative of the polar satellite due to the availability of its long-term series, while the Himawari-8 satellite will be used as the data source for the geostationary satellite because of its improved TIRS. For the study area, Hong Kong Special Administrative Region (HK SAR) will be selected; this is due to the heterogeneity in the landscape of the region. LST data will be retrieved from both satellites using the Split window algorithm (SWA), and the resulting data will be validated by comparing satellite-derived LST data with temperature data from automatic WS in HK SAR. The LST data from the satellite data will then be separated based on the land use classification in HK SAR using the Global Land Cover by National Mapping Organization version3 (GLCNMO 2013) data. The relationship between LST data from Landsat-8 and Himawari-8 will then be investigated based on the land-use class and over different seasons of the year in order to account for seasonal variation in their relationship. The resulting relationship will be spatially and statistically analyzed and graphically visualized for detailed interpretation. Findings from this study will reveal the relationship between the two satellite data based on the land use classification within the study area and the seasons of the year. While the information provided by this study will help in the optimal combination of LST data from Polar (Landsat-8) and geostationary (Himawari-8) satellites, it will also serve as a roadmap in the annual and diurnal urban heat (UHI) analysis in Hong Kong SAR.Keywords: automatic weather station, Himawari-8, Landsat-8, land surface temperature, land use classification, split window algorithm, urban heat island
Procedia PDF Downloads 731319 Medicinal Plants: An Antiviral Depository with Complex Mode of Action
Authors: Daniel Todorov, Anton Hinkov, Petya Angelova, Kalina Shishkova, Venelin Tsvetkov, Stoyan Shishkov
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Human herpes viruses (HHV) are ubiquitous pathogens with a pandemic spread across the globe. HHV type 1 is the main causative agent of cold sores and fever blisters around the mouth and on the face, whereas HHV type 2 is generally responsible for genital herpes outbreaks. The treatment of both viruses is more or less successful with antivirals from the nucleoside analogues group. Their wide application increasingly leads to the emergence of resistant mutants In the past, medicinal plants have been used to treat a number of infectious and non-infectious diseases. Their diversity and ability to produce the vast variety of secondary metabolites according to the characteristics of the environment give them the potential to help us in our warfare with viral infections. The variable chemical characteristics and complex composition is an advantage in the treatment of herpes since the emergence of resistant mutants is significantly complicated. The screening process is difficult due to the lack of standardization. That is why it is especially important to follow the mechanism of antiviral action of plants. On the one hand, it may be expected to interact with its compounds, resulting in enhanced antiviral effects, and the most appropriate environmental conditions can be chosen to maximize the amount of active secondary metabolites. During our study, we followed the activity of various plant extracts on the viral replication cycle as well as their effect on the extracellular virion. We obtained our results following the logical sequence of the experimental settings - determining the cytotoxicity of the extracts, evaluating the overall effect on viral replication and extracellular virion.During our research, we have screened a variety of plant extracts for their antiviral activity against both virus replication and the virion itself. We investigated the effect of the extracts on the individual stages of the viral replication cycle - viral adsorption, penetration and the effect on replication depending on the time of addition. If there are positive results in the later experiments, we had studied the activity over viral adsorption, penetration and the effect of replication according to the time of addition. Our results indicate that some of the extracts from the Lamium album have several targets. The first stages of the viral life cycle are most affected. Several of our active antiviral agents have shown an effect on extracellular virion and adsorption and penetration processes. Our research over the last decade has shown several curative antiviral plants - some of which are from the Lamiacea family. The rich set of active ingredients of the plants in this family makes them a good source of antiviral preparation.Keywords: human herpes virus, antiviral activity, Lamium album, Nepeta nuda
Procedia PDF Downloads 1541318 Assessment of Physical Activity and Sun Exposure of Saudi Patients with Type 2 Diabetes Mellitus in Ramadan and Non-Ramadan Periods
Authors: Abdullah S. Alghamdi, Khaled Alghamdi, Richard O. Jenkins, Parvez I. Haris
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Background: Physical activity is an important factor in the treatment and prevention of type 2 diabetes mellitus (T2DM). Reduction in HbA1c level, an important diabetes biomarker, was reported in patients who increased their daily physical activity. Although the ambient temperature was reported to be positively correlated to a negative impact on health and increase the incidences of diabetes, the exposure to bright sunlight was recently found to be associated with enhanced insulin sensitivity and improved beta-cell function. How Ramadan alters physical activity, and especially sunlight exposure, has not been adequately investigated. Aim: This study aimed to assess the physical activity and sun exposure of Saudis with T2DM over different periods (before, during, and after Ramadan) and related this to HbA1c levels. Methods: This study recruited 82 Saudis with T2DM, who chose to fast during Ramadan, from the Endocrine and Diabetic Centre of Al Iman General Hospital, Riyadh, Saudi Arabia. Ethical approvals for this study were obtained from De Montfort University and Saudi Ministry of Health. Physical activity and sun exposure were assessed by a self-administered questionnaire. Physical activity was estimated using the International Physical Activity Questionnaire (IPAQ), while the sun exposure was assessed by asking the patients about their hours per week of direct exposure to the sun, and daily hours spent outdoors. Blood samples were collected in each period for measuring HbA1c. Results: Low physical activity was observed in more than 60% of the patients, with no significant changes between periods. There were no significant variances between periods in the daily hours spent outdoors and the total number of weekly hours of direct exposure to the sun. The majority of patients reported only few hours of exposure to the sun (1h or less per week) and time spent outdoors (1h or less per day). The mean HbA1c significantly changed between periods (P = 0.001), with lowest level during Ramadan. There were significant differences in the mean HbA1c between the groups for the level of physical activity (P < 0.001), with significant lower mean HbA1c in the higher-level group. There were no significant variances in the mean of HbA1c between the groups for the daily hours spent outdoors. The mean HbA1c of the patients, who reported never in their total weekly hours of exposure to the sun, was significantly lower than the mean HbA1c of those who reported 1 hour or less (P = 0.001). Conclusion: Physical inactivity was prevalent among the study population with very little exposure to the sun or time spent outdoors. Higher level of physical activity was associated with lower mean HbA1c levels. Encouraging T2DM patients to achieve the recommended levels of physical activity may help them to obtain greater benefits of Ramadan fasting, such as reducing their HbA1c levels. The impact of low direct exposure to the sun and the time spent outdoors needs to be further investigated in both healthy and diabetic patients.Keywords: diabetes, fasting, physical activity, sunlight, Ramadan
Procedia PDF Downloads 1601317 Carbon Capture and Storage Using Porous-Based Aerogel Materials
Authors: Rima Alfaraj, Abeer Alarawi, Murtadha AlTammar
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The global energy landscape heavily relies on the oil and gas industry, which faces the critical challenge of reducing its carbon footprint. To address this issue, the integration of advanced materials like aerogels has emerged as a promising solution to enhance sustainability and environmental performance within the industry. This study thoroughly examines the application of aerogel-based technologies in the oil and gas sector, focusing particularly on their role in carbon capture and storage (CCS) initiatives. Aerogels, known for their exceptional properties, such as high surface area, low density, and customizable pore structure, have garnered attention for their potential in various CCS strategies. The review delves into various fabrication techniques utilized in producing aerogel materials, including sol-gel, supercritical drying, and freeze-drying methods, to assess their suitability for specific industry applications. Beyond fabrication, the practicality of aerogel materials in critical areas such as flow assurance, enhanced oil recovery, and thermal insulation is explored. The analysis spans a wide range of applications, from potential use in pipelines and equipment to subsea installations, offering valuable insights into the real-world implementation of aerogels in the oil and gas sector. The paper also investigates the adsorption and storage capabilities of aerogel-based sorbents, showcasing their effectiveness in capturing and storing carbon dioxide (CO₂) molecules. Optimization of pore size distribution and surface chemistry is examined to enhance the affinity and selectivity of aerogels towards CO₂, thereby improving the efficiency and capacity of CCS systems. Additionally, the study explores the potential of aerogel-based membranes for separating and purifying CO₂ from oil and gas streams, emphasizing their role in the carbon capture and utilization (CCU) value chain in the industry. Emerging trends and future perspectives in integrating aerogel-based technologies within the oil and gas sector are also discussed, including the development of hybrid aerogel composites and advanced functional components to further enhance material performance and versatility. By synthesizing the latest advancements and future directions in aerogel used for CCS applications in the oil and gas industry, this review offers a comprehensive understanding of how these innovative materials can aid in transitioning towards a more sustainable and environmentally conscious energy landscape. The insights provided can assist in strategic decision-making, drive technology development, and foster collaborations among academia, industry, and policymakers to promote the widespread adoption of aerogel-based solutions in the oil and gas sector.Keywords: CCS, porous, carbon capture, oil and gas, sustainability
Procedia PDF Downloads 411316 Damage to Strawberries Caused by Simulated Transport
Authors: G. La Scalia, M. Enea, R. Micale, O. Corona, L. Settanni
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The quality and condition of perishable products delivered to the market and their subsequent selling prices are directly affected by the care taken during harvesting and handling. Mechanical injury, in fact, occurs at all stages, from pre-harvest operations through post-harvest handling, packing and transport to the market. The main implications of this damage are the reduction of the product’s quality and economical losses related to the shelf life diminution. For most perishable products, the shelf life is relatively short and it is typically dictated by microbial growth related to the application of dynamic and static loads during transportation. This paper presents the correlation between vibration levels and microbiological growth on strawberries and woodland strawberries and detects the presence of volatile organic compounds (VOC) in order to develop an intelligent logistic unit capable of monitoring VOCs using a specific sensor system. Fresh fruits were exposed to vibrations by means of a vibrating table in a temperature-controlled environment. Microbiological analyses were conducted on samples, taken at different positions along the column of the crates. The values obtained were compared with control samples not exposed to vibrations and the results show that different positions along the column influence the development of bacteria, yeasts and filamentous fungi.Keywords: microbiological analysis, shelf life, transport damage, volatile organic compounds
Procedia PDF Downloads 4211315 The Potential of Tempo-Oxidized Cellulose Nanofibers to Replace EthylenE-propylene-Diene Monomer Rubber
Authors: Sibel Dikmen Kucuk, Yusuf Guner
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In recent years, petroleum-based polymers began to be limited due to the effects on the human and environmental point of view in many countries. Thus, organic-based biodegradable materials have attracted much interest in the composite industry because of environmental concerns. As a result of this, it has been asked that inorganic and petroleum-based materials should be reduced and altered with biodegradable materials. In this point, in this study, it is aimed to investigate the potential of the use of TEMPO (2,2,6,6- tetramethylpiperidine 1-oxyl)-mediated oxidation nano-fibrillated cellulose instead of EPDM (ethylene-propylene-diene monomer) rubber, which is a petroleum-based material. Thus, the exchange of petroleum-based EPDM rubber with organic-based cellulose nanofibers, which are environmentally friendly (green) and biodegradable, will be realized. The effect of tempo-oxidized cellulose nanofibers (TCNF) instead of EPDM rubber was analyzed by rheological, mechanical, chemical, thermal, and aging analyses. The aged surfaces were visually scrutinized, and surface morphological changes were examined via scanning electron microscopy (SEM). The results obtained showed that TEMPO oxidation nano-fibrillated cellulose could be used at an amount of 1.0 and 2.2 phr resulting the values stay within tolerance according to customer standard and without any chemical degradation, crack, color change or staining.Keywords: EPDM, lignin, green materials, biodegradable fillers
Procedia PDF Downloads 1251314 Construction and Demolition Waste Management in Indian Cities
Authors: Vaibhav Rathi, Soumen Maity, Achu R. Sekhar, Abhijit Banerjee
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Construction sector in India is extremely resource and carbon intensive. It contributes to significantly to national greenhouse emissions. At the resource end the industry consumes significant portions of the output from mining. Resources such as sand and soil are most exploited and their rampant extraction is becoming constant source of impact on environment and society. Cement is another resource that is used in abundance in building and construction and has a direct impact on limestone resources. Though India is rich in cement grade limestone resource, efforts have to be made for sustainable consumption of this resource to ensure future availability. Use of these resources in high volumes in India is a result of rapid urbanization. More cities have grown to a population of million plus in the last decade and million plus cities are growing further. To cater to needs of growing urban population of construction activities are inevitable in the coming future thereby increasing material consumption. Increased construction will also lead to substantial increase in end of life waste generation from Construction and Demolition (C&D). Therefore proper management of C&D waste has the potential to reduce environmental pollution as well as contribute to the resource efficiency in the construction sector. The present study deals with estimation, characterisation and documenting current management practices of C&D waste in 10 Indian cities of different geographies and classes. Based on primary data the study draws conclusions on the potential of C&D waste to be used as an alternative to primary raw materials. The estimation results show that India generates 716 million tons of C&D waste annually, placing the country as second largest C&D waste generator in the world after China. The study also aimed at utilization of C&D waste in to building materials. The waste samples collected from various cities have been used to replace 100% stone aggregates in paver blocks without any decrease in strength. However, management practices of C&D waste in cities still remains poor instead of notification of rules and regulations notified for C&D waste management. Only a few cities have managed to install processing plant and set up management systems for C&D waste. Therefore there is immense opportunity for management and reuse of C&D waste in Indian cities.Keywords: building materials, construction and demolition waste, cities, environmental pollution, resource efficiency
Procedia PDF Downloads 3041313 Validation of Two Field Base Dynamic Balance Tests in the Activation of Selected Hip and Knee Stabilizer Muscles
Authors: Mariam A. Abu-Alim
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The purpose of this study was to validate muscle activation amplitudes of two field base dynamic balance tests that are used as strengthen and motor control exercises too in the activation of selected hip and knee stabilizer muscles. Methods: Eighteen college-age females students (21±2 years; 65.6± 8.7 kg; 169.7±8.1 cm) who participated at least for 30 minutes in physical activity most days of the week volunteered. The wireless BIOPAC (MP150, BIOPAC System. Inc, California, USA) surface electromyography system was used to validate the activation of the Gluteus Medius and the Adductor Magnus of hip stabilizer muscles; and the Hamstrings, Quadriceps, and the Gastrocnemius of the knee stabilizer muscles. Surface electrodes (EL 503, BIOPAC, System. Inc) connected to dual wireless EMG BioNormadix Transmitters were place on selected muscles of participants dominate side. Manual muscle testing was performed to obtain the maximal voluntary isometric contraction (MVIC) in which all collected muscle activity data during the three reaching direction: anterior, posteromedial, posterolateral of the Star Excursion Balance Test (SEBT) and the Y-balance Test (YBT) data could be normalized. All participants performed three trials for each reaching direction of the SEBT and the YBT. The domanial leg trial for each participant was selected for analysis which was also the standing leg. Results: the selected hip stabilizer muscles (Gluteus Medius, Adductor Magnus) were both greater than 100%MVIC during the performance of the SEBT and in all three directions. Whereas, selected knee stabilizer muscles had greater activation 0f 100% MVIC and were significantly more activated during the performance of the YBT test in all three reaching directions. The results showed that the posterolateral and the postmedial reaching directions for both dynamic balance tests had greater activation levels and greater than 200%MVIC for all tested muscles expect of the hamstrings. Conclusion: the results of this study showed that the SEBT and the YBT had validated high levels of muscular activity for the hip and the knee stabilizer muscles; which can be used to represent the improvement, strength, control and the decreasing in the injury levels. Since these selected hip and knee stabilizer muscles, represent 35% of all athletic injuries depending on the type of sport.Keywords: dynamic balance tests, electromyography, hip stabilizer muscles, nee stabilizer muscles
Procedia PDF Downloads 1511312 Pickering Dry Emulsion System for Dissolution Enhancement of Poorly Water Soluble Drug (Fenofibrate)
Authors: Nitin Jadhav, Pradeep R. Vavia
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Poor water soluble drugs are difficult to promote for oral drug delivery as they demonstrate poor and variable bioavailability because of its poor solubility and dissolution in GIT fluid. Nowadays lipid based formulations especially self microemulsifying drug delivery system (SMEDDS) is found as the most effective technique. With all the impressive advantages, the need of high amount of surfactant (50% - 80%) is the major drawback of SMEDDS. High concentration of synthetic surfactant is known for irritation in GIT and also interference with the function of intestinal transporters causes changes in drug absorption. Surfactant may also reduce drug activity and subsequently bioavailability due to the enhanced entrapment of drug in micelles. In chronic treatment these issues are very conspicuous due to the long exposure. In addition the liquid self microemulsifying system also suffers from stability issues. Recently one novel approach of solid stabilized micro and nano emulsion (Pickering emulsion) has very admirable properties such as high stability, absence or very less concentration of surfactant and easily converts into the dry form. So here we are exploring pickering dry emulsion system for dissolution enhancement of anti-lipemic, extremely poorly water soluble drug (Fenofibrate). Oil moiety for emulsion preparation was selected mainly on the basis of higher solubility of drug. Captex 300 was showed higher solubility for fenofibrate, hence selected as oil for emulsion. With Silica (solid stabilizer); Span 20 was selected to improve the wetting property of it. Emulsion formed by Silica and Span20 as stabilizer at the ratio 2.5:1 (silica: span 20) was found very stable at the particle size 410 nm. The prepared emulsion was further preceded for spray drying and formed microcapsule evaluated for in-vitro dissolution study, in-vivo pharmacodynamic study and characterized for DSC, XRD, FTIR, SEM, optical microscopy etc. The in vitro study exhibits significant dissolution enhancement of formulation (85 % in 45 minutes) as compared to plain drug (14 % in 45 minutes). In-vivo study (Triton based hyperlipidaemia model) exhibits significant reduction in triglyceride and cholesterol with formulation as compared to plain drug indicating increasing in fenofibrate bioavailability. DSC and XRD study exhibit loss of crystallinity of drug in microcapsule form. FTIR study exhibit chemical stability of fenofibrate. SEM and optical microscopy study exhibit spherical structure of globule coated with solid particles.Keywords: captex 300, fenofibrate, pickering dry emulsion, silica, span20, stability, surfactant
Procedia PDF Downloads 4981311 A Comparison and Discussion of Modern Anaesthetic Techniques in Elective Lower Limb Arthroplasties
Authors: P. T. Collett, M. Kershaw
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Introduction: The discussion regarding which method of anesthesia provides better results for lower limb arthroplasty is a continuing debate. Multiple meta-analysis has been performed with no clear consensus. The current recommendation is to use neuraxial anesthesia for lower limb arthroplasty; however, the evidence to support this decision is weak. The Enhanced Recovery After Surgery (ERAS) society has recommended, either technique can be used as part of a multimodal anesthetic regimen. A local study was performed to see if the current anesthetic practice correlates with the current recommendations and to evaluate the efficacy of the different techniques utilized. Method: 90 patients who underwent total hip or total knee replacements at Nevill Hall Hospital between February 2019 to July 2019 were reviewed. Data collected included the anesthetic technique, day one opiate use, pain score, and length of stay. The data was collected from anesthetic charts, and the pain team follows up forms. Analysis: The average of patients undergoing lower limb arthroplasty was 70. Of those 83% (n=75) received a spinal anaesthetic and 17% (n=15) received a general anaesthetic. For patients undergoing knee replacement under general anesthetic the average day, one pain score was 2.29 and 1.94 if a spinal anesthetic was performed. For hip replacements, the scores were 1.87 and 1.8, respectively. There was no statistical significance between these scores. Day 1 opiate usage was significantly higher in knee replacement patients who were given a general anesthetic (45.7mg IV morphine equivalent) vs. those who were operated on under spinal anesthetic (19.7mg). This difference was not noticeable in hip replacement patients. There was no significant difference in length of stay between the two anesthetic techniques. Discussion: There was no significant difference in the day one pain score between the patients who received a general or spinal anesthetic for either knee or hip replacements. The higher pain scores in the knee replacement group overall are consistent with this being a more painful procedure. This is a small patient population, which means any difference between the two groups is unlikely to be representative of a larger population. The pain scale has 4 points, which means it is difficult to identify a significant difference between pain scores. Conclusion: There is currently little standardization between the different anesthetic approaches utilized in Nevill Hall Hospital. This is likely due to the lack of adherence to a standardized anesthetic regimen. In accordance with ERAS recommends a standard anesthetic protocol is a core component. The results of this study and the guidance from the ERAS society will support the implementation of a new health board wide ERAS protocol.Keywords: anaesthesia, orthopaedics, intensive care, patient centered decision making, treatment escalation
Procedia PDF Downloads 1271310 Differentiated Instruction for All Learners: Strategies for Full Inclusion
Authors: Susan Dodd
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This presentation details the methodology for teachers to identify and support a population of students who have historically been overlooked in regards to their educational needs. The twice exceptional (2e) student is a learner who is considered gifted and also has a learning disability, as defined by the Individuals with Disabilities Education Act (IDEA). Many of these students remain underserved throughout their educational careers because their exceptionalities may mask each other, resulting in a special population of students who are not achieving to their fullest potential. There are three common scenarios that may make the identification of a 2e student challenging. First, the student may have been identified as gifted, and her disability may go unnoticed. She could also be considered an under-achiever, or she may be able to compensate for her disability under the school works becomes more challenging. In the second scenario, the student may be identified as having a learning disability and is only receiving remedial services where his giftedness will not be highlighted. His overall IQ scores may be misleading because they were impacted by his learning disability. In the third scenario, the student is able to compensate for her ability well enough to maintain average scores, and she goes undetected as both gifted and learning disabled. Research in the area identifies the complexity involved in identifying 2e students, and how multiple forms of assessment are required. It is important for teachers to be aware of the common characteristics exhibited by many 2e students, so these learners can be identified and appropriately served. Once 2e students have been identified, teachers are then challenged to meet the varying needs of these exceptional learners. Strength-based teaching entails simultaneously providing gifted instruction as well as individualized accommodations for those students. Research in this field has yielded strategies that have proven helpful for teaching 2e students, as well as other students who may be struggling academically. Differentiated instruction, while necessary in all classrooms, is especially important for 2e students, as is encouragement for academic success. Teachers who take the time to really know their students will have a better understanding of each student’s strengths and areas for growth, and therefore tailor instruction to extend the intellectual capacities for optimal achievement. Teachers should also understand that some learning activities can prove very frustrating to students, and these activities can be modified based on individual student needs. Because 2e students can often become discouraged by their learning challenges, it is especially important for teachers to assist students in recognizing their own strengths and maintaining motivation for learning. Although research on the needs of 2e students has spanned across two decades, this population remains underserved in many educational institutions. Teacher awareness of the identification of and the support strategies for 2e students is critical for their success.Keywords: gifted, learning disability, special needs, twice exceptional
Procedia PDF Downloads 1791309 Mimosa Tannin – Starch - Sugar Based Wood Adhesive
Authors: Salise Oktay, Nilgün Kizilcan, Başak Bengü
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At present, formaldehyde based adhesives such as urea formaldehyde (UF), melamine formaldehyde (MF), melamine – urea formaldehyde (MUF), etc. are mostly used in wood based panel industry because of their high reactivity, chemical versatility, and economic competitiveness. However, formaldehyde based wood adhesives are produced from non- renewable resources. Hence, there has been a growing interest in the development of environment friendly, economically competitive, bio-based wood adhesives in order to meet wood based panel industry requirements. In this study, as formaldehyde free adhesive, Mimosa tannin, starch, sugar based wood adhesivewas synthesized. Citric acid and tartaric acid were used as hardener for the resin system. Solid content, viscosity, and gel time analyzes of the prepared adhesive were performed in order to evaluate the adhesive processability. FTIR characterization technique was used to elucidate the chemical structures of the cured adhesivesamples. In order to evaluate the performance of the prepared bio-based resin formulation, particleboards were produced in a laboratory scale, and mechanical, physical properties of the boards were investigated. Besides, the formaldehyde contents of the boards were determined by using the perforator method. The obtained results revealed that the developed bio-based wood adhesive formulation can be a good potential candidate to use wood based panel industry with some developments.Keywords: bio-based wood adhesives, mimosa tannin, corn starch, sugar, polycarboxyclic acid
Procedia PDF Downloads 2331308 Durability Study of Pultruded CFRP Plates under Sustained Bending in Distilled Water and Seawater Immersions: Effects on the Visco-Elastic Properties
Authors: Innocent Kafodya, Guijun Xian
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This paper presents effects of distilled water, seawater and sustained bending strains of 30% and 50% ultimate strain at room temperature, on the durability of unidirectional pultruded carbon fiber reinforced polymer (CFRP) plates. In this study, dynamic mechanical analyzer (DMA) was used to investigate the synergic effects of the immersions and bending strains on the visco-elastic properties of (CFRP) such as storage modulus, tan delta and glass transition temperature. The study reveals that the storage modulus and glass transition temperature increase while tan delta peak decreases in the initial stage of both immersions due to the progression of curing. The storage modulus and Tg subsequently decrease and tan delta increases due to the matrix plasticization. The blister induced damages in the unstrained seawater samples enhance water uptake and cause more serious degradation of Tg and storage modulus than in water immersion. Increasing sustained bending decreases Tg and storage modulus in a long run for both immersions due to resin matrix cracking and debonding. The combined effects of immersions and strains are not clearly reflected due to the statistical effects of DMA sample sizes and competing processes of molecular reorientation and postcuring.Keywords: pultruded CFRP plate, bending strain, glass transition temperature, storage modulus, tan delta
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