Search results for: employee theft behavior
942 Effect of Sulphur Concentration on Microbial Population and Performance of a Methane Biofilter
Authors: Sonya Barzgar, J. Patrick, A. Hettiaratchi
Abstract:
Methane (CH4) is reputed as the second largest contributor to greenhouse effect with a global warming potential (GWP) of 34 related to carbon dioxide (CO2) over the 100-year horizon, so there is a growing interest in reducing the emissions of this gas. Methane biofiltration (MBF) is a cost effective technology for reducing low volume point source emissions of methane. In this technique, microbial oxidation of methane is carried out by methane-oxidizing bacteria (methanotrophs) which use methane as carbon and energy source. MBF uses a granular medium, such as soil or compost, to support the growth of methanotrophic bacteria responsible for converting methane to carbon dioxide (CO₂) and water (H₂O). Even though the biofiltration technique has been shown to be an efficient, practical and viable technology, the design and operational parameters, as well as the relevant microbial processes have not been investigated in depth. In particular, limited research has been done on the effects of sulphur on methane bio-oxidation. Since bacteria require a variety of nutrients for growth, to improve the performance of methane biofiltration, it is important to establish the input quantities of nutrients to be provided to the biofilter to ensure that nutrients are available to sustain the process. The study described in this paper was conducted with the aim of determining the influence of sulphur on methane elimination in a biofilter. In this study, a set of experimental measurements has been carried out to explore how the conversion of elemental sulphur could affect methane oxidation in terms of methanotrophs growth and system pH. Batch experiments with different concentrations of sulphur were performed while keeping the other parameters i.e. moisture content, methane concentration, oxygen level and also compost at their optimum level. The study revealed the tolerable limit of sulphur without any interference to the methane oxidation as well as the particular sulphur concentration leading to the greatest methane elimination capacity. Due to the sulphur oxidation, pH varies in a transient way which affects the microbial growth behavior. All methanotrophs are incapable of growth at pH values below 5.0 and thus apparently are unable to oxidize methane. Herein, the certain pH for the optimal growth of methanotrophic bacteria is obtained. Finally, monitoring methane concentration over time in the presence of sulphur is also presented for laboratory scale biofilters.Keywords: global warming, methane biofiltration (MBF), methane oxidation, methanotrophs, pH, sulphur
Procedia PDF Downloads 226941 A Study on Reinforced Concrete Beams Enlarged with Polymer Mortar and UHPFRC
Authors: Ga Ye Kim, Hee Sun Kim, Yeong Soo Shin
Abstract:
Many studies have been done on the repair and strengthening method of concrete structure, so far. The traditional retrofit method was to attach fiber sheet such as CFRP (Carbon Fiber Reinforced Polymer), GFRP (Glass Fiber Reinforced Polymer) and AFRP (Aramid Fiber Reinforced Polymer) on the concrete structure. However, this method had many downsides in that there are a risk of debonding and an increase in displacement by a shortage of structure section. Therefore, it is effective way to enlarge the structural member with polymer mortar or Ultra-High Performance Fiber Reinforced Concrete (UHPFRC) as a means of strengthening concrete structure. This paper intends to investigate structural performance of reinforced concrete (RC) beams enlarged with polymer mortar and compare the experimental results with analytical results. Nonlinear finite element analyses were conducted to compare the experimental results and predict structural behavior of retrofitted RC beams accurately without cost consuming experimental process. In addition, this study aims at comparing differences of retrofit material between commonly used material (polymer mortar) and recently used material (UHPFRC) by conducting nonlinear finite element analyses. In the first part of this paper, the RC beams having different cover type were fabricated for the experiment and the size of RC beams was 250 millimeters in depth, 150 millimeters in width and 2800 millimeters in length. To verify the experiment, nonlinear finite element models were generated using commercial software ABAQUS 6.10-3. From this study, both experimental and analytical results demonstrated good strengthening effect on RC beam and showed similar tendency. For the future, the proposed analytical method can be used to predict the effect of strengthened RC beam. In the second part of the study, the main parameters were type of retrofit materials. The same nonlinear finite element models were generated to compare the polymer mortar with UHPFRCC. Two types of retrofit material were evaluated and retrofit effect was verified by analytical results.Keywords: retrofit material, polymer mortar, UHPFRC, nonlinear finite element analysis
Procedia PDF Downloads 408940 A Systematic Review of Pedometer-or Accelerometer-Based Interventions for Increasing Physical Activity in Low Socioeconomic Groups
Authors: Shaun G. Abbott, Rebecca C. Reynolds, James B. Etter, John B. F. de Wit
Abstract:
The benefits of physical activity (PA) on health are well documented. Low socioeconomic status (SES) is associated with poor health, with PA a suggested mediator. Pedometers and accelerometers offer an effective behavior change tool to increase PA levels. While the role of pedometer and accelerometer use in increasing PA is recognized in many populations, little is known in low-SES groups. We are aiming to assess the effectiveness of pedometer- and accelerometer-based interventions for increasing PA step count and improving subsequent health outcomes among low-SES groups of high-income countries. Medline, Embase, PsycINFO, CENTRAL and SportDiscus databases were searched to identify articles published before 10th July, 2015; using search terms developed from previous systematic reviews. Inclusion criteria are: low-SES participants classified by income, geography, education, occupation or ethnicity; study duration minimum 4 weeks; an intervention and control group; wearing of an unsealed pedometer or accelerometer to objectively measure PA as step counts per day for the duration of the study. We retrieved 2,142 articles from our database searches, after removal of duplicates. Two investigators independently reviewed titles and abstracts of these articles (50% each) and a combined 20% sample were reviewed to account for inter-assessor variation. We are currently verifying the full texts of 430 articles. Included studies will be critically appraised for risk of bias using guidelines suggested by the Cochrane Public Health Group. Two investigators will extract data concerning the intervention; study design; comparators; steps per day; participants; context and presence or absence of obesity and/or chronic disease. Heterogeneity amongst studies is anticipated, thus a narrative synthesis of data will be conducted with the simplification of selected results into percentage increases from baseline to allow for between-study comparison. Results will be presented at the conference in December if selected.Keywords: accelerometer, pedometer, physical activity, socioeconomic, step count
Procedia PDF Downloads 320939 Sexual Dimorphism in the Sensorial Structures of the Antenna of Thygater aethiops (Hymenoptera: Apidae) and Its Relation with Some Corporal Parameters
Authors: Wendy Carolina Gomez Ramirez, Rodulfo Ospina Torres
Abstract:
Thygater aethiops is a species of solitary bee with a neotropical distribution that has been adapted to live in urban environments. This species of bee presents a marked sexual dimorphism since the males have antenna almost as long as their body different from the females that present antenna with smaller size. In this work, placoid sensilla were studied, which are structures that appear in the antenna and are involved in the detection of substances both, for reproduction and for the search of food. The aim of this study was to evaluate the differences between these sensory structures in the different sexes, for which males and females were captured. Later some body measures were taken such as fresh weight with abdomen and without it, since the weight could be modified by the stomach content; other measures were taken as the total antenna length and length of the flagellum and flagelomere. After negative imprints of the antenna were made using nail polish, the imprint was cut with a microblade and mounted onto a microscope slide. The placoid sensilla were visible on the imprint, so they were counted manually on the 100x objective lens of the optical microscope. Initially, the males presented a specific distribution pattern in two types of sensilla: trichoid and placoid, the trichoid were found aligned in the dorsal face of the antenna and the placoid were distributed along the entire antenna; that was different to the females since they did not present a distribution pattern the sensilla were randomly organized. It was obtained that the males, because they have a longer antenna, have a greater number of sensilla in relation to the females. Additionally, it was found that there was no relationship between the weight and the number of sensilla, but there was a positive relationship between the length of the antenna, the length of the flagellum and the number of sensilla. The relationship between the number of sensilla per unit area in each of the sexes was also calculated, which showed that, on average, males have 4.2 ± 0.38 sensilla per unit area and females present 2.2 ± 0.20 and likewise a significant difference between sexes. This dimorphism found may be related to the sexual behavior of the species, since it has been demonstrated that males are more adapted to the perception of substances related to reproduction than to the search of food.Keywords: antenna, olfactory organ, sensilla, sexual dimorphism, solitary bees
Procedia PDF Downloads 158938 Effect of Climate Change and Water Sources: Sustainability of Rural Water Sanitation and Hygiene of Tanahun District
Authors: Bharat Sapkota
Abstract:
Nepal is the one of the victim country of climate change. Decreasing snow line, sometimes higher and sometime non-rain fall are common phenomena in hill area. Natural flood disaster and drought is also common every year in certain place of the country. So this paper analyze the effect of climate and natural water sources for sustainability of water sanitation and hygiene of Tanahun district. It is one of the Rural Water Supply and Sanitation Project Western Nepal Phase-II (RWSSP-WN Phase-II) project district out of 14 project districts of western and mid-western Nepal. RWSSP-WN II is a bilateral development cooperation of governments of Nepal and Finland. Big investment is still going on in water sanitation and hygiene sector but sustainability is still a challenge throughout the country. So RWSSP-WN has started the strengthen of the capacity of local Governments to deliver services in water supply, sanitation and hygiene and its sustainability through the implementation of cross cutting approach of climate change and disaster risk reduction. The study shows that the average yield in 685 natural point sources were around 0.045 l/s in 2014 but it was twice as high in 2004 i.e. 0.09 l/s. The maximum measured yield in 2014 was 1.87 l/s, whereas, the maximum yield was 3 l/s in 2004. Likewise, spring source mean and maximum yield measured in 2014 were 0.16 l/s and 3.33 l/s respectively, whereas, mean and maximum yields in 2004 were 0.204 l/s and 3 l/s respectively. Small streams average yield measured in 2014 was 0.32 l/s with the maximum of around 4.99 l/s. In 2004, mean and maximum yields of streams were 0.485 l/s and 5 l/s respectively. The overall climate between years 2002 to 2013 and measured yield data between 2004 and 2014 shows climate as one of the causes of water source decline. The temperature is rising with pace of 0.041°C per year and rainfall is decreased by 16.8 mm/year. The Khosla’s empirical formula shows decrease of 1.7 cm/year in runoff. At present sustainability of water, sanitation and hygiene is more challenge due to sources decreasing in the district. Sanitation and hygiene total behavior change and watershed conservation as well as design and implementation of recharge pound construction are the way forward of sustainability of water, sanitation and hygiene.Keywords: water sanitation, hygiene, sustainability, climate change
Procedia PDF Downloads 329937 The Communicational Behaviors of the Nurses Towards 'Crying Patient'
Authors: Hacer Kobya Bulut, Kıymet Yeşilçiçek Çalık, Birsel Canan Demirbağ, Hacer Erdöl, Songül Aktaş
Abstract:
Introduction: As an expression of an emotion which always exists in life, crying is regarded as one of the problematic behaviors of patients by nurses. Towards such patients, nurses may exhibit emotional and behavioral reactions such as feeling helpless, anger, indifferent, defense, and opposition. However crying either meets a need, reduces the tension to cope with problems or helps patient to gain strength. Therefore, nurses must accept that crying is a normal mechanism that reduces emotional tension and should approach a crying patient accordingly. Objective: This study was carried out to evaluate the communicational behaviors of the nurses towards ‘crying patient’. Methods: This descriptive study was conducted with the nurses working at a university hospital in a city in the Eastern Black Sea in June-September 2015. The entire universe was tried to be reached without sampling. 90% of the population was reached and the study was completed with 309 nurses who volunteered to participate in the study. Data were collected through a questionnaire which was prepared reviewing the literature by researchers. Data were evaluated in SPSS analysis program using percentages, numbers and chi-square test with the 95% confidence interval and p <0.05significance level. Findings: The findings showed that the average age of nurses was 31.52 ± 7.96, work experience was 10:09 ± 7.69 and only 22.7% had training about ‘approach to crying patient’ during their education. 97.1% of the nurses often faced with crying patients in their professional lives, 62.8% stated that they faced crying women patients. When they see crying patients, 84.8% of the nurses ‘do not want the patient to cry’, 80.9% wonder ‘why they are crying’, % 79.6 ‘feel uneasiness’,% 79.3 ‘feel sorry’ and 41.4% ‘ feel helpless’. The question ‘Why do you think the patient is crying?’ was answered by 93.5% nurses as ‘they are suffering’, by 86.1% ‘they are helpless’, 80.9% ‘they are sad’, 79.6% ‘they need help’, 54.4% ‘because they feel inadequate,’ and 44.7% ‘they fail to control their crying behavior. ‘How do you approach to your patient when she/he is crying?’ question was answered by 82.5% of nurses as ‘I would console’, 77.3% as ‘I would ask the reason’, 63.1% as ‘I would try to stop her from crying’ all of which are actually inappropriate nursing approaches. However, 92.2% of the nurses stated that ‘I do not judge the crying patient’, ‘87.1% said ‘I allocate time to crying patients’ and 85.8% said ‘ I ask patient whether they want to cry alone’. The study showed that educational background and work experience of the nurses affected the appropriate approach to crying patients (P <0.05). Conclusion: As a result of the study, it was found out that nurses do not want patients to cry, so they exhibit inappropriate approach such as consoling the patients and they have difficulty in approaching crying patients.Keywords: approach to patient, communication, crying patient, nurse, Turkey
Procedia PDF Downloads 195936 Critical Appraisal, Smart City Initiative: China vs. India
Authors: Suneet Jagdev, Siddharth Singhal, Dhrubajyoti Bordoloi, Peesari Vamshidhar Reddy
Abstract:
There is no universally accepted definition of what constitutes a Smart City. It means different things to different people. The definition varies from place to place depending on the level of development and the willingness of people to change and reform. It tries to improve the quality of resource management and service provisions for the people living in the cities. Smart city is an urban development vision to integrate multiple information and communication technology (ICT) solutions in a secure fashion to manage the assets of a city. But most of these projects are misinterpreted as being technology projects only. Due to urbanization, a lot of informal as well government funded settlements have come up during the last few decades, thus increasing the consumption of the limited resources available. The people of each city have their own definition of Smart City. In the imagination of any city dweller in India is the picture of a Smart City which contains a wish list of infrastructure and services that describe his or her level of aspiration. The research involved a comparative study of the Smart City models in India and in China. Behavioral changes experienced by the people living in the pilot/first ever smart cities have been identified and compared. This paper discussed what is the target of the quality of life for the people in India and in China and how well could that be realized with the facilities being included in these Smart City projects. Logical and comparative analyses of important data have been done, collected from government sources, government papers and research papers by various experts on the topic. Existing cities with historically grown infrastructure and administration systems will require a more moderate step-by-step approach to modernization. The models were compared using many different motivators and the data is collected from past journals, interacting with the people involved, videos and past submissions. In conclusion, we have identified how these projects could be combined with the ongoing small scale initiatives by the local people/ small group of individuals and what might be the outcome if these existing practices were implemented on a bigger scale.Keywords: behavior change, mission monitoring, pilot smart cities, social capital
Procedia PDF Downloads 285935 Experimental Investigation of the Out-of-Plane Dynamic Behavior of Adhesively Bonded Composite Joints at High Strain Rates
Authors: Sonia Sassi, Mostapha Tarfaoui, Hamza Ben Yahia
Abstract:
In this investigation, an experimental technique in which the dynamic response, damage kinetic and heat dissipation are measured simultaneously during high strain rates on adhesively bonded joints materials. The material used in this study is widely used in the design of structures for military applications. It was composed of a 45° Bi-axial fiber-glass mat of 0.286 mm thickness in a Polyester resin matrix. In adhesive bonding, a NORPOL Polyvinylester of 1 mm thickness was used to assemble the composite substrate. The experimental setup consists of a compression Split Hopkinson Pressure Bar (SHPB), a high-speed infrared camera and a high-speed Fastcam rapid camera. For the dynamic compression tests, 13 mm x 13 mm x 9 mm samples for out-of-plane tests were considered from 372 to 1030 s-1. Specimen surface is controlled and monitored in situ and in real time using the high-speed camera which acquires the damage progressive in specimens and with the infrared camera which provides thermal images in time sequence. Preliminary compressive stress-strain vs. strain rates data obtained show that the dynamic material strength increases with increasing strain rates. Damage investigations have revealed that the failure mainly occurred in the adhesive/adherent interface because of the brittle nature of the polymeric adhesive. Results have shown the dependency of the dynamic parameters on strain rates. Significant temperature rise was observed in dynamic compression tests. Experimental results show that the temperature change depending on the strain rate and the damage mode and their maximum exceed 100 °C. The dependence of these results on strain rate indicates that there exists a strong correlation between damage rate sensitivity and heat dissipation, which might be useful when developing damage models under dynamic loading tacking into account the effect of the energy balance of adhesively bonded joints.Keywords: adhesive bonded joints, Hopkinson bars, out-of-plane tests, dynamic compression properties, damage mechanisms, heat dissipation
Procedia PDF Downloads 206934 Anticorrosive Performances of “Methyl Ester Sulfonates” Biodegradable Anionic Synthetized Surfactants on Carbon Steel X 70 in Oilfields
Authors: Asselah Amel, Affif Chaouche M'yassa, Toudji Amira, Tazerouti Amel
Abstract:
This study covers two aspects ; the biodegradability and the performances in corrosion inhibition of a series of synthetized surfactants namely Φ- sodium methyl ester sulfonates (Φ-MES: C₁₂-MES, C₁₄-MES and C₁₆-MES. The biodegradability of these organic compounds was studied using the respirometric method, ‘the standard ISO 9408’. Degradation was followed by analysis of dissolved oxygen using the dissolved oxygen meter over 28 days and the results were compared with that of sodium dodecyl sulphate (SDS). The inoculum used consists of activated sludge taken from the aeration basin of the biological wastewater treatment plant in the city of Boumerdes-Algeria. In addition, the anticorrosive performances of Φ-MES surfactants on a carbon steel "X70" were evaluated in an injection water from a well of Hassi R'mel region- Algeria, known as Baremian water, and are compared to sodium dodecyl sulphate. Two technics, the weight loss and the linear polarization resistance corrosion rate (LPR) are used allowing to investigate the relationships between the concentrations of these synthetized surfactants and their surface properties, surface coverage and inhibition efficiency. Various adsorption isotherm models were used to characterize the nature of adsorption and explain their mechanism. The results show that the MES anionic surfactants was readily biodegradable, degrading faster than SDS, about 88% for C₁₂-MES compared to 66% for the SDS. The length of their carbon chain affects their biodegradability; the longer the chain, the lower the biodegradability. The inhibition efficiency of these surfactants is around 78.4% for C₁₂-MES, 76.60% for C₁₄-MES and 98.19% for C₁₆-MES and increases with their concentration and reaches a maximum value around their critical micelle concentrations ( CMCs). Scanning electron microscopy coupled to energy dispersive X-ray spectroscopy allowed to the visualization of a good adhesion of the protective film formed by the surfactants to the surface of the steel. The studied surfactants show the Langmuirian behavior from which the thermodynamic parameters as adsorption constant (Kads), standard free energy of adsorption (〖∆G〗_ads^0 ) are determined. Interaction of the surfactants with steel surface have involved physisorptions.Keywords: corrosion, surfactants, adsorption, adsorption isotherems
Procedia PDF Downloads 88933 Structure and Mechanics Patterns in the Assembly of Type V Intermediate-Filament Protein-Based Fibers
Authors: Mark Bezner, Shani Deri, Tom Trigano, Kfir Ben-Harush
Abstract:
Intermediate filament (IF) proteins-based fibers are among the toughest fibers in nature, as was shown by native hagfish slime threads and by synthetic fibers that are based on type V IF-proteins, the nuclear lamins. It is assumed that their mechanical performance stems from two major factors: (1) the transition from elastic -helices to stiff-sheets during tensile load; and (2) the specific organization of the coiled-coil proteins into a hierarchical network of nano-filaments. Here, we investigated the interrelationship between these two factors by using wet-spun fibers based on C. elegans (Ce) lamin. We found that Ce-lamin fibers, whether assembled in aqueous or alcoholic solutions, had the same nonlinear mechanical behavior, with the elastic region ending at ~5%. The pattern of the transition was, however, different: the ratio between -helices and -sheets/random coils was relatively constant until a 20% strain for fibers assembled in an aqueous solution, whereas for fibers assembled in 70% ethanol, the transition ended at a 6% strain. This structural phenomenon in alcoholic solution probably occurred through the transition between compacted and extended conformation of the random coil, and not between -helix and -sheets, as cycle analyses had suggested. The different transition pattern can also be explained by the different higher order organization of Ce-lamins in aqueous or alcoholic solutions, as demonstrated by introducing a point mutation in conserved residue in Ce-lamin gene that alter the structure of the Ce-lamins’ nano-fibrils. In addition, biomimicking the layered structure of silk and hair fibers by coating the Ce-lamin fiber with a hydrophobic layer enhanced fiber toughness and lead to a reversible transition between -helix and the extended conformation. This work suggests that different hierarchical structures, which are formed by specific assembly conditions, lead to diverse secondary structure transitions patterns, which in turn affect the fibers’ mechanical properties.Keywords: protein-based fibers, intermediate filaments (IF) assembly, toughness, structure-property relationships
Procedia PDF Downloads 103932 Seismic Evaluation of Multi-Plastic Hinge Design Approach on RC Shear Wall-Moment Frame Systems against Near-Field Earthquakes
Authors: Mohsen Tehranizadeh, Mahboobe Forghani
Abstract:
The impact of higher modes on the seismic response of dual structural system consist of concrete moment-resisting frame and with RC shear walls is investigated against near-field earthquakes in this paper. a 20 stories reinforced concrete shear wall-special moment frame structure is designed in accordance with ASCE7 requirements and The nonlinear model of the structure was performed on OpenSees platform. Nonlinear time history dynamic analysis with 3 near-field records are performed on them. In order to further understand the structural collapse behavior in the near field, the response of the structure at the moment of collapse especially the formation of plastic hinges is explored. The results revealed that the amplification of moment at top of the wall due to higher modes, the plastic hinge can form in the upper part of wall, even when designed and detailed for plastic hinging at the base only (according to ACI code).on the other hand, shear forces in excess of capacity design values can develop due to the contribution of the higher modes of vibration to dynamic response due to the near field can cause brittle shear or sliding failure modes. The past investigation on shear walls clearly shows the dual-hinge design concept is effective at reducing the effects of the second mode of response. An advantage of the concept is that, when combined with capacity design, it can result in relaxation of special reinforcing detailing in large portions of the wall. In this study, to investigate the implications of multi-design approach, 4 models with varies arrangement of hinge plastics at the base and height of the shear wall are considered. results base on time history analysis showed that the dual or multi plastic hinges approach can be useful in order to control the high moment and shear demand of higher mode effect.Keywords: higher mode effect, Near-field earthquake, nonlinear time history analysis, multi plastic hinge design
Procedia PDF Downloads 420931 Environmental Conditions Simulation Device for Evaluating Fungal Growth on Wooden Surfaces
Authors: Riccardo Cacciotti, Jiri Frankl, Benjamin Wolf, Michael Machacek
Abstract:
Moisture fluctuations govern the occurrence of fungi-related problems in buildings, which may impose significant health risks for users and even lead to structural failures. Several numerical engineering models attempt to capture the complexity of mold growth on building materials. From real life observations, in cases with suppressed daily variations of boundary conditions, e.g. in crawlspaces, mold growth model predictions well correspond with the observed mold growth. On the other hand, in cases with substantial diurnal variations of boundary conditions, e.g. in the ventilated cavity of a cold flat roof, mold growth predicted by the models is significantly overestimated. This study, founded by the Grant Agency of the Czech Republic (GAČR 20-12941S), aims at gaining a better understanding of mold growth behavior on solid wood, under varying boundary conditions. In particular, the experimental investigation focuses on the response of mold to changing conditions in the boundary layer and its influence on heat and moisture transfer across the surface. The main results include the design and construction at the facilities of ITAM (Prague, Czech Republic) of an innovative device allowing for the simulation of changing environmental conditions in buildings. It consists of a square section closed circuit with rough dimensions 200 × 180 cm and cross section roughly 30 × 30 cm. The circuit is thermally insulated and equipped with an electric fan to control air flow inside the tunnel, a heat and humidity exchange unit to control the internal RH and variations in temperature. Several measuring points, including an anemometer, temperature and humidity sensor, a loading cell in the test section for recording mass changes, are provided to monitor the variations of parameters during the experiments. The research is ongoing and it is expected to provide the final results of the experimental investigation at the end of 2022.Keywords: moisture, mold growth, testing, wood
Procedia PDF Downloads 120930 The Use of Orthodontic Pacifiers to Prevent Pacifier Induced Malocclusion - A Literature Review
Authors: Maliha Ahmed Suleman, Sidra Ahmed Suleman
Abstract:
Introduction: The use of pacifiers is common amongst infants and young children as a comforting behavior. These non-nutritive sucking habits can be detrimental to the developing occlusion should they persist while the permanent dentition is established. Orthodontic pacifiers have been recommended as an alternative to conventional pacifiers as they are considered to have less interference with orofacial development. However, there is a lack of consensus on whether this is true. Aim and objectives: To review the prevalence of malocclusion associated with the use of orthodontic pacifiers. Methodology: Literature was identified through a rigorous search of the Embase, Pubmed, CINAHL, and Cochrane Library databases. Articles published from 2000 onwards were included. In total, 5 suitable papers were identified. Results: One study showed that the use of orthodontic pacifiers increased the risk of malocclusion, as seen through a greater prevalence of accentuated overjet, posterior crossbites, and anterior open bites in comparison to individuals who did not use pacifiers. However, this study found that there was a clinically significant reduction in the prevalence of anterior open bites amongst orthodontic pacifier users in comparison to conventional pacifier users. Another study found that both types of pacifiers lead to malocclusion; however, they found no difference in the mean overjet and prevalence of anterior open bites amongst conventional and orthodontic pacifier users. In contrast, one study suggested that orthodontic pacifiers do not seem to be related to the development of malocclusions in the primary dentitions, and using them between the ages of 0-3 months was actually beneficial as it prevents thumb-sucking habits. One of the systemic reviews concluded that orthodontic pacifiers do not seem to reduce the occurrence of posterior crossbites; however, they could reduce the development of open bites by virtue of their thin neck design. Whereas another systematic review concluded that there were no differences as to the effects on the stomatognathic system when comparing conventional and orthodontic pacifiers. Conclusion: There is limited and conflicting evidence to support the notion that orthodontic pacifiers can reduce the prevalence of malocclusion when compared to conventional pacifiers. Well-designed randomized controlled trials are required in the future in order to thoroughly assess the effects of orthodontic pacifiers on the developing occlusion and orofacial structures.Keywords: orthodontics, pacifier, malocclusion, review
Procedia PDF Downloads 75929 Mitigation of Lithium-ion Battery Thermal Runaway Propagation Through the Use of Phase Change Materials Containing Expanded Graphite
Authors: Jayson Cheyne, David Butler, Iain Bomphray
Abstract:
In recent years, lithium-ion batteries have been used increasingly for electric vehicles and large energy storage systems due to their high-power density and long lifespan. Despite this, thermal runaway remains a significant safety problem because of its uncontrollable and irreversible nature - which can lead to fires and explosions. In large-scale lithium-ion packs and modules, thermal runaway propagation between cells can escalate fire hazards and cause significant damage. Thus, safety measures are required to mitigate thermal runaway propagation. The current research explores composite phase change materials (PCM) containing expanded graphite (EG) for thermal runaway mitigation. PCMs are an area of significant interest for battery thermal management due to their ability to absorb substantial quantities of heat during phase change. Moreover, the introduction of EG can support heat transfer from the cells to the PCM (owing to its high thermal conductivity) and provide shape stability to the PCM during phase change. During the research, a thermal model was established for an array of 16 cylindrical cells to simulate heat dissipation with and without the composite PCM. Two conditions were modeled, including the behavior during charge/discharge cycles (i.e., throughout regular operation) and thermal runaway. Furthermore, parameters including cell spacing, composite PCM thickness, and EG weight percentage (WT%) were varied to establish the optimal material parameters for enabling thermal runaway mitigation and effective thermal management. Although numerical modeling is still ongoing, initial findings suggest that a 3mm PCM containing 15WT% EG can effectively suppress thermal runaway propagation while maintaining shape stability. The next step in the research is to validate the model through controlled experimental tests. Additionally, with the perceived fire safety concerns relating to PCM materials, fire safety tests, including UL-94 and Limiting Oxygen Index (LOI), shall be conducted to explore the flammability risk.Keywords: battery safety, electric vehicles, phase change materials, thermal management, thermal runaway
Procedia PDF Downloads 125928 Study of Porous Metallic Support for Intermediate-Temperature Solid Oxide Fuel Cells
Authors: S. Belakry, D. Fasquelle, A. Rolle, E. Capoen, R. N. Vannier, J. C. Carru
Abstract:
Solid oxide fuel cells (SOFCs) are promising devices for energy conversion due to their high electrical efficiency and eco-friendly behavior. Their performance is not only influenced by the microstructural and electrical properties of the electrodes and electrolyte but also depends on the interactions at the interfaces. Nowadays, commercial SOFCs are electrically efficient at high operating temperatures, typically between 800 and 1000 °C, which restricts their real-life applications. The present work deals with the objectives to reduce the operating temperature and to develop cost-effective intermediate-temperature solid oxide fuel cells (IT-SOFCs). This work focuses on the development of metal-supported solid oxide fuel cells (MS-IT-SOFCs) that would provide cheaper SOFC cells with increased lifetime and reduced operating temperature. In the framework, the local company TIBTECH brings its skills for the manufacturing of porous metal supports. This part of the work focuses on the physical, chemical, and electrical characterizations of porous metallic supports (stainless steel 316 L and FeCrAl alloy) under different exposure conditions of temperature and atmosphere by studying oxidation, mechanical resistance, and electrical conductivity of the materials. Within the target operating temperature (i.e., 500 to 700 ° C), the stainless steel 316 L and FeCrAl alloy slightly oxidize in the air and H2, but don’t deform; whereas under Ar atmosphere, they oxidize more than with previously mentioned atmospheres. Above 700 °C under air and Ar, the two metallic supports undergo high oxidation. From 500 to 700 °C, the resistivity of FeCrAl increases by 55%. But nevertheless, the FeCrAl resistivity increases more slowly than the stainless steel 316L resistivity. This study allows us to verify the compatibility of electrodes and electrolyte materials with metallic support at the operating requirements of the IT-SOFC cell. The characterizations made in this context will also allow us to choose the most suitable fabrication process for all functional layers in order to limit the oxidation of the metallic supports.Keywords: stainless steel 316L, FeCrAl alloy, solid oxide fuel cells, porous metallic support
Procedia PDF Downloads 85927 An In-Depth Comparison Study of Canadian and Danish's Entrepreneurship and Education System
Authors: Amna Khaliq
Abstract:
In this research paper, a comparison study has been undertaken between Canada and Denmark to analyze the education system between the countries in entrepreneurship. Denmark, a land of high wages and high taxes, and Canada, a land of immigrants and opportunities, have seen a positive relationship in entrepreneurs' growth. They are both considered one of the top ten countries to start a business and to have government support globally. However, education is entirely free to Danish students, including university degrees, compared to Canadians, which can further hurdle for Canadian millennials to grow in the business world—the business experience more growth with educated entrepreneurs with international backgrounds in new immigrants. Denmark has seen a gradual increase in female entrepreneurs over the decade but is still lower than OECD countries. Compassionate management and work-life balance are prioritized in Denmark, unlike in Canada. Danish are early adopters of technology and have excellent infrastructure to support the technology industry, whereas Canada is still a service-oriented and manufacturer-based country. 2018 has been the highest number of opening businesses for Canada and Denmark. Some companies offer high wages, hiring bonuses, flexible working hours, wellness, and mental health benefits during Pandemic to keep the companies running and keep their workers' morale high. Pandemic has taught consumers new patterns to shop online. It is essential now to use technology and automation to increase productivity in businesses. Only those companies will survive that are applying this strategy. The Pandemic has ultimately changed entrepreneurs' and employees' behavior in the business world. Along with Ph.D. professors, entrepreneurs should be allowed to teach at learning intuitions. Millennials turn out to be the most entrepreneurial generation in both countries. Entrepreneurship education will only be beneficial when students create businesses and learn from real-life experiences. Managing physical, mental, emotional, and psychological health while dealing with high pressure in entrepreneurship are soft skills learned through practical work.Keywords: entrepreneurship education, millennials, pandemic, Denmark, Canada
Procedia PDF Downloads 95926 Predicting Expectations of Non-Monogamy in Long-Term Romantic Relationships
Authors: Michelle R. Sullivan
Abstract:
Positive romantic relationships and marriages offer a buffer against a host of physical and emotional difficulties. Conversely, poor relationship quality and marital discord can have deleterious consequences for individuals and families. Research has described non-monogamy, infidelity, and consensual non-monogamy, as both consequential and causal of relationship difficulty, or as a unique way a couple strives to make a relationship work. Much research on consensual non-monogamy has built on feminist theory and critique. To the author’s best knowledge, to date, no studies have examined the predictive relationship between individual and relationship characteristics and expectations of non-monogamy. The current longitudinal study: 1) estimated the prevalence of expectations of partner non-monogamy and 2) evaluated whether gender, sexual identity, age, education, how a couple met, and relationship quality were predictive expectations of partner non-monogamy. This study utilized the publically available longitudinal dataset, How Couples Meet and Stay Together. Adults aged 18- to 98-years old (n=4002) were surveyed by phone over 5 waves from 2009-2014. Demographics and how a couple met were gathered through self-report in Wave 1, and relationship quality and expectations of partner non-monogamy were gathered through self-report in Waves 4 and 5 (n=1047). The prevalence of expectations of partner non-monogamy (encompassing both infidelity and consensual non-monogamy) was 4.8%. Logistic regression models indicated that sexual identity, gender, education, and relationship quality were significantly predictive of expectations of partner non-monogamy. Specifically, male gender, lower education, identifying as lesbian, gay, or bisexual, and a lower relationship quality scores were predictive of expectations of partner non-monogamy. Male gender was not predictive of expectations of partner non-monogamy in the follow up logistic regression model. Age and whether a couple met online were not associated with expectations of partner non-monogamy. Clinical implications include awareness of the increased likelihood of lesbian, gay, and bisexual individuals to have an expectation of non-monogamy and the sequelae of relationship dissatisfaction that may be related. Future research directions could differentiate between non-monogamy subtypes and the person and relationship variables that lead to the likelihood of consensual non-monogamy and infidelity as separate constructs, as well as explore the relationship between predicting partner behavior and actual partner behavioral outcomes.Keywords: open relationship, polyamory, infidelity, relationship satisfaction
Procedia PDF Downloads 152925 Application of Transportation Models for Analysing Future Intercity and Intracity Travel Patterns in Kuwait
Authors: Srikanth Pandurangi, Basheer Mohammed, Nezar Al Sayegh
Abstract:
In order to meet the increasing demand for housing care for Kuwaiti citizens, the government authorities in Kuwait are undertaking a series of projects in the form of new large cities, outside the current urban area. Al Mutlaa City located to the north-west of the Kuwait Metropolitan Area is one such project out of the 15 planned new cities. The city accommodates a wide variety of residential developments, employment opportunities, commercial, recreational, health care and institutional uses. This paper examines the application of comprehensive transportation demand modeling works undertaken in VISUM platform to understand the future intracity and intercity travel distribution patterns in Kuwait. The scope of models developed varied in levels of detail: strategic model update, sub-area models representing future demand of Al Mutlaa City, sub-area models built to estimate the demand in the residential neighborhoods of the city. This paper aims at offering model update framework that facilitates easy integration between sub-area models and strategic national models for unified traffic forecasts. This paper presents the transportation demand modeling results utilized in informing the planning of multi-modal transportation system for Al Mutlaa City. This paper also presents the household survey data collection efforts undertaken using GPS devices (first time in Kuwait) and notebook computer based digital survey forms for interviewing representative sample of citizens and residents. The survey results formed the basis of estimating trip generation rates and trip distribution coefficients used in the strategic base year model calibration and validation process.Keywords: innovative methods in transportation data collection, integrated public transportation system, traffic forecasts, transportation modeling, travel behavior
Procedia PDF Downloads 214924 An Association Model to Correlate the Experimentally Determined Mixture Solubilities of Methyl 10-Undecenoate with Methyl Ricinoleate in Supercritical Carbon Dioxide
Authors: V. Mani Rathnam, Giridhar Madras
Abstract:
Fossil fuels are depleting rapidly as the demand for energy, and its allied chemicals are continuously increasing in the modern world. Therefore, sustainable renewable energy sources based on non-edible oils are being explored as a viable option as they do not compete with the food commodities. Oils such as castor oil are rich in fatty acids and thus can be used for the synthesis of biodiesel, bio-lubricants, and many other fine industrial chemicals. There are several processes available for the synthesis of different chemicals obtained from the castor oil. One such process is the transesterification of castor oil, which results in a mixture of fatty acid methyl esters. The main products in the above reaction are methyl ricinoleate and methyl 10-undecenoate. To separate these compounds, supercritical carbon dioxide (SCCO₂) was used as a green solvent. SCCO₂ was chosen as a solvent due to its easy availability, non-toxic, non-flammable, and low cost. In order to design any separation process, the preliminary requirement is the solubility or phase equilibrium data. Therefore, the solubility of a mixture of methyl ricinoleate with methyl 10-undecenoate in SCCO₂ was determined in the present study. The temperature and pressure range selected for the investigation were T = 313 K to 333 K and P = 10 MPa to 18 MPa. It was observed that the solubility (mol·mol⁻¹) of methyl 10-undecenoate varied from 2.44 x 10⁻³ to 8.42 x 10⁻³ whereas it varied from 0.203 x 10⁻³ to 6.28 x 10⁻³ for methyl ricinoleate within the chosen operating conditions. These solubilities followed a retrograde behavior (characterized by the decrease in the solubility values with the increase in temperature) throughout the range of investigated operating conditions. An association theory model, coupled with regular solution theory for activity coefficients, was developed in the present study. The deviation from the experimental data using this model can be quantified using the average absolute relative deviation (AARD). The AARD% for the present compounds is 4.69 and 8.08 for methyl 10-undecenoate and methyl ricinoleate, respectively in a mixture of methyl ricinoleate and methyl 10-undecenoate. The maximum solubility enhancement of 32% was observed for the methyl ricinoleate in a mixture of methyl ricinoleate and methyl 10-undecenoate. The highest selectivity of SCCO₂ was observed to be 12 for methyl 10-undecenoate in a mixture of methyl ricinoleate and methyl 10-undecenoate.Keywords: association theory, liquid mixtures, solubilities, supercritical carbon dioxide
Procedia PDF Downloads 126923 Exercise and Social Activities for Elderly with an Impairment Who Are Living Alone in the Community: Effects and Influencing Factors of a Dutch Program
Authors: Renate Verkaik, Mieke Rijken, Hennie Boeije
Abstract:
Elderly who are living alone and who are having one or more impairments are vulnerable for a loss of wellbeing and institutionalization. Physical exercise and social activities together with peers have the potential to make them more resilient. The Dutch program ‘More Resilience, Longer at Home’ initiated by FNO funded 126 local projects to stimulate vulnerable older citizens to participate in exercise and social activities, and as such to improve wellbeing and independent living. The program evaluation addressed the following questions: (1) what are the effects of the program on older (65+) participants exercise behavior, social activities and what is the relationship with wellbeing?, (2) which factors contribute to successful implementation of the projects and their outcomes? A mixed method approach was used. Effects on participants were assessed with a short survey, containing questions on exercise, social engagement, daily functioning, loneliness and life satisfaction. Results of the participants were compared with those of a reference group from the Dutch national population. Perceived influencing factors were investigated with a questionnaire for project leaders. This questionnaire was based on site visits and interviews with project leaders, volunteers and participating elderly. Preliminary results show that social engagement of the participating elderly rises significantly (p ≤ .05) as do their exercise levels and daily functioning. They experience less social loneliness, but not less emotional loneliness. Additionally, there is a positive association between daily functioning and life satisfaction and between exercise and life satisfaction. Perceived influencing factors that contribute to successful implementation of the projects can be categorized in 4 types: (1) characteristics of the activities; (2) profiles of the involved staff (professionals and volunteers), (3) characteristics of the organization, (4) the social political environment. Conclusions are that local projects have been successful in stimulating older citizens to participate in exercise and social activities. Multiple factors need to be addressed to ensure sustainability and scaling-up of the good practices.Keywords: elderly living alone in the community, exercise and social activities, resilience, quality of life
Procedia PDF Downloads 124922 TP53 Mutations in Molecular Subtypes of Breast Cancer in Young Pakistani Patients
Authors: Nadia Naseem, Farwa Batool, Nasir Mehmood, AbdulHannan Nagi
Abstract:
Background: The incidence and mortality of breast cancer vary significantly in geographically distinct populations. In Pakistan, breast cancer has shown an increase in incidence in young females and is characterized by more aggressive behavior. The tumor suppressor TP53 gene is a crucial genetic factor that plays a significant role in breast carcinogenesis. This study investigated the TP53 mutations in molecular subtypes of both nodes negative and positive breast cancer in young Pakistani patients. Material and Methods: p53, Estrogen Receptor (ER), Progesterone Receptor (PR), Her-2 neu and Ki 67 expressions were analyzed immunohistochemically in a series of 75 node negative (A) and 75 node positive (B) young (aged: 19-40 years) breast cancer patients diagnosed between 2014 to 2017 at two leading hospitals of Punjab, Pakistan. Tumor tissue specimens and peripheral blood samples were examined for TP53 mutations by direct sequencing of the gene (exons 4-9). The relation of TP53 mutations to these markers and clinicopathological data was investigated. Results: Mean age of the patients was 32.4 + 9.1 SD. Invasive breast carcinoma was the most frequent histological variant (A=92%, B=94.6%). Grade 3 carcinoma was the commonest grade (A=72%, B=81.3%). Triple negative cases (ER-, PR-, Her-2) formed most of the molecular subtypes (A=44%, B=50.6%). A total of 17.2% (A: 6.6%, B: 10.6%) patients showed TP53 mutations. Mutations were significantly more frequent in triple negative cases (A: 74.8%, B: 62.2%) compared to HER2-positive patients (P < 0.0001). In the multivariate analysis of the whole patient group, the independent prognosticator were triple negative cases (P=0.021), TP53 overexpression by IHC (P=0.001) and advanced-stage disease (P=0.007). No statistically significant correlation between TP53 mutations and clinicopathological parameters was found (P < 0.05). Conclusions: It is concluded that TP53 mutations are infrequently present in breast carcinoma of young Pakistani population and there was no significant correlation between p53 mutation and early onset disease. Immunohistochemically detected TP53 expression in our resource-constrained to set up can be beneficial in predicting mutations at the younger age in our population.Keywords: immunohistochemistry (IHC), invasive breast carcinoma (IBC), Pakistan, TP53
Procedia PDF Downloads 141921 Sexual Health Experiences of Older Men: Health Care Professionals' Perspectives
Authors: Andriana E. Tran, Anna Chur-Hansen
Abstract:
Sexual health is an important aspect of overall wellbeing. This study aimed to explore the sexual health experiences of men aged 50 years and over from the perspective of health care professional participants who were specializing in sexual health care and who consulted with older men. A total of ten interviews were conducted. Eleven themes were identified regarding men’s experiences with sexual health care as reported by participants. 1) Biologically focused: older male clients focus largely on the biological aspect of their sexual health without consideration of other factors which might affect their functioning. 2) Psychological concerns: there is an interaction between mental and sexual health but older male clients do not necessarily see this. 3) Medicalization of sexual functioning: advances in medicine that aid with erectile difficulties which consequently mean that older men tend to favor a medical solution to their sexual concerns. 4) Masculine identity: sexual health concerns are linked to older male clients’ sense of masculinity. 5) Penile functionality: most concerns that older male clients have center on their penile functionality. 6) Relationships: many male clients seek sexual help as they believe it improves relationships. Conversely, having supportive partners may mean older male clients focus less on the physicality of sex. 7) Grief and loss: men experience grief and loss – the loss of their sexual functioning, grief from loss of a long-term partner, and loss of intimacy and privacy when moving from independent living to residential care. 8) Social stigma: older male clients experience stigma around aging sexuality and sex in general. 9) Help-seeking behavior: older male clients will usually seek mechanistic solution for biological sexual concerns, such as medication used for penile dysfunction. 10) Dismissed by health care professionals: many older male clients seek specialist sexual health care without the knowledge of their doctors as they feel dismissed due to lack of expertise, lack of time, and the doctor’s personal attitudes and characteristics. Finally, 11) Lack of resources: there is a distinct lack of resources and training to understand sexuality for healthy older men. These findings may inform future research, professional training, public health campaigns and policies for sexual health in older men.Keywords: ageing, biopsychosocial model, men's health, sexual health
Procedia PDF Downloads 166920 Krill-Herd Step-Up Approach Based Energy Efficiency Enhancement Opportunities in the Offshore Mixed Refrigerant Natural Gas Liquefaction Process
Authors: Kinza Qadeer, Muhammad Abdul Qyyum, Moonyong Lee
Abstract:
Natural gas has become an attractive energy source in comparison with other fossil fuels because of its lower CO₂ and other air pollutant emissions. Therefore, compared to the demand for coal and oil, that for natural gas is increasing rapidly world-wide. The transportation of natural gas over long distances as a liquid (LNG) preferable for several reasons, including economic, technical, political, and safety factors. However, LNG production is an energy-intensive process due to the tremendous amount of power requirements for compression of refrigerants, which provide sufficient cold energy to liquefy natural gas. Therefore, one of the major issues in the LNG industry is to improve the energy efficiency of existing LNG processes through a cost-effective approach that is 'optimization'. In this context, a bio-inspired Krill-herd (KH) step-up approach was examined to enhance the energy efficiency of a single mixed refrigerant (SMR) natural gas liquefaction (LNG) process, which is considered as a most promising candidate for offshore LNG production (FPSO). The optimal design of a natural gas liquefaction processes involves multivariable non-linear thermodynamic interactions, which lead to exergy destruction and contribute to process irreversibility. As key decision variables, the optimal values of mixed refrigerant flow rates and process operating pressures were determined based on the herding behavior of krill individuals corresponding to the minimum energy consumption for LNG production. To perform the rigorous process analysis, the SMR process was simulated in Aspen Hysys® software and the resulting model was connected with the Krill-herd approach coded in MATLAB. The optimal operating conditions found by the proposed approach significantly reduced the overall energy consumption of the SMR process by ≤ 22.5% and also improved the coefficient of performance in comparison with the base case. The proposed approach was also compared with other well-proven optimization algorithms, such as genetic and particle swarm optimization algorithms, and was found to exhibit a superior performance over these existing approaches.Keywords: energy efficiency, Krill-herd, LNG, optimization, single mixed refrigerant
Procedia PDF Downloads 149919 Evaluation of Occupational Exposure to Chromium for Welders of Stainless Steel
Authors: L. Musak, J. Valachova, T. Vasicko, O. Osina
Abstract:
Stainless steel is resistant to electrochemical corrosion by passivation. Welders are greatly exposed to welding fumes of toxic metals, which added to this steel. The content of chromium (Cr) is above 11.5%, Ni and Mo from 2 to 6.5%. The aim of the study was the evaluation of occupational exposure to Cr, chromosome analysis and valuation of individual susceptibility polymorphism of gene CCND1 c.870 G>A. The exposed group was consisted from 117 welders of stainless steels. The average age was 38.43 years and average exposure time 7.14 years. Smokers represented 40.17%. The control group consisted of 123 non-exposed workers with an average age of 39.74 years and time employment 16.67 years. Smokers accounted for 22.76%. Analysis of Cr in blood and urine was performed by atomic absorption spectrophotometry (AAS Varian SpectraAA 30P) with electrothermal decomposition of the sample in the graphite furnace. For the evaluation of chromosomal aberrations (CA) cytogenetic analysis of peripheral blood lymphocytes was used. Gene polymorphism was determined by PCR-RFLP reaction using appropriate primers and restriction enzymes. For statistic analysis the Mann-Whitney U-test was used. The mean Cr level in blood of exposed group was 0.095 µmol/l (0.019 min - max 0.504). No value exceeds the average normal value. The mean value Cr in urine was 7.9 µmol/mol creatinine (min 0.026 to max 19.26). The total number of CA was 1.86% in compared to 1.70% controls. (CTA-type 0.90% vs. 0.80% and CSA-type 0.96% vs. 0.90%). In the number of total CA statistical difference was observed between smokers and non-smokers of exposed group (S-1.57% vs. NS-2.04%, P<0.05). In CCND1 gene polymorphisms was observed the increasing of the total CA with wild-type allele (WT) via heterozygous to the VAR genotype (1.44% <1.82% <2.13%). A statistically higher incidence of CTA-type aberrations in variant genotypes between exposed and control groups was observed (1.22% vs. 0.59%, P <0.05). The work place is usually higher source of exposure to harmful factors. Workers need consistent and frequent health control. In assessing the risk of adverse effects of metals it is important to consider their persistence, behavior and bioavailability. Prolonged exposure to carcinogens may not manifest symptoms of poisoning, but delayed effects may occur, which resulted in a higher incidence of malignant tumors.Keywords: CCND1, genotoxicity, polymorphism, stainless steel, welders
Procedia PDF Downloads 343918 Poly(N-Vinylcaprolactam-Co-Itaconic Acid-Co-Ethylene Glycol Dimethacrylate)-Based Microgels Embedded in Chitosan Matrix for Controlled Release of Ketoprofen
Authors: Simone F. Medeiros, Jessica M. Fonseca, Gizelda M. Alves, Danilo M. Santos, Sérgio P. Campana-Filho, Amilton M. Santos
Abstract:
Stimuli responsive and biocompatible hydrogel nanoparticles have gained special attention as systems for potential applications in controlled release of drugs to improve their therapeutic efficacy while minimizing side effects. In this work, novel solid dispersions based on thermo- and pH-responsive poly(N-vinylcaprolactam-co-itaconic acid-co-ethylene- glycol dimethacrylate) hydrogel nanoparticles embedded in chitosan matrices were prepared via spray drying for controlled release of ketoprofen. Firstly, the hydrogel nanoparticles containing ketoprofen were prepared via precipitation polymerization and their stimuli-responsive behavior, thermal properties, chemical composition, encapsulation efficiency and morphology were characterized. Then, hydrogel nanoparticles with different particles size were embedded into chitosan matrices via spray-drying. Scanning electron microscopy (SEM) analyses were performed to investigate the particles size, dispersity and morphology. Finally, ketoprofen release profiles were studied as a function of pH and temperature. Chitosan/poly(NVCL-co-IA-co-EGDMA)-ketoprofen microparticles presented spherical shape, rough surface and pronounced agglomeration, indicating that hydrogels nanoparticles loaded with ketoprofen modified the surface of chitosan matrix. The maximum encapsulation efficiency of ketoprofen into hydrogel nanoparticles was 57.8% and the electrostatic interactions between amino groups from chitosan and carboxylic groups from hydrogel nanoparticles were able to control ketoprofen release. The hydrogel nanoparticles themselves were capable to retard the release of ketoprofen-loaded until 48h of in vitro release tests, while their incorporation into chitosan matrix achieved a maximum percentage of drug release of 45%, using a mass ratio of chitosan: poly(NVCL-co-IA-co-EGDMA equal to 10:7, and 69%, using a mass ratio of chitosan: poly(NVCL-co-IA-co-EGDMA equal to 5:2.Keywords: hydrogel nanoparticles, poly(N-vinylcaprolactam-co-itaconic acid-co-ethylene- glycol dimethacrylate), chitosan, ketoprofen, spray-drying
Procedia PDF Downloads 251917 Psychological Impact of the COVID-19 Pandemic on Health Care Workers in Tunisia: Risk and Protective Factor
Authors: Ahmed Sami Hammami, Mohamed Jellazi
Abstract:
Background: The aim of the study is to evaluate the magnitude of different psychological outcomes among Tunisian health care professionals (HCP) during the COVID-19 pandemic and to identify the associated factors. Methods: HCP completed a cross-sectional questionnaire from April 4th to April, 28th 2020. The survey collected demographic information, factors that may interfere with the psychological outcomes, behavior changes and mental health measurements. The latter was assessed through 3 scales; the 7-item questions Insomnia Severity Index, the 2-item Patient Health Questionnaire and the 2-item Generalized Anxiety Disorder. Multivariable logistic regression was conducted to identify factors associated with psychological outcomes. Results: A total of 503 HCP successfully completed the survey; among those, n=493 consented to enroll in the study, 411 [83.4%] were physicians, 323 [64.2%] were women and 271 [55%] had a second-line working position. A significant proportion of HCP had anxiety 35.7%, depression 35.1% and insomnia 23.7%. Females, those with psychiatric history and those using public transport exhibited the highest proportions for overall symptoms compared to other groups e.g., depression among females vs. males: 44,9% vs. 18,2%, P=0.00. Those with a previous medical history and nurses, had more anxiety and insomnia compared to other groups e.g. anxiety among nurses vs. interns/residents vs. attending 45,1% vs 36,1% vs 27,5%; p=0.04. Multivariable logistic regression showed that female gender was a risk factor for all psychological outcomes e.g. female sex increased the odds of anxiety by 2.86; 95% confidence interval [CI], 1, 78-4, 60; P=0.00, whereas having a psychiatric history was a risk factor for both anxiety and insomnia. (e.g. for insomnia OR=2,86; 95% [CI], 1,78-4,60; P=0.00), Having protective equipment was associated with lower risk for depression (OR=0,41; 95% CI, 0,27-0,62; P=0.00) and anxiety. Physical activity was also protective against depression and anxiety (OR=0,41, 95% CI, 0,25-0,67, P=0.00). Conclusion: Psychological symptoms are usually undervalued among HCP, though the COVID-19 pandemic played a major role in exacerbating this burden. Prompt psychological support should be endorsed and simple measures such as physical activity and ensuring the necessary protection are paramount to improve mental health outcomes and the quality of care provided to patients.Keywords: COVID-19 pandemic, health care professionals, mental health, protective factors, psychological symptoms, risk factors
Procedia PDF Downloads 185916 EcoLife and Greed Index Measurement: An Alternative Tool to Promote Sustainable Communities and Eco-Justice
Authors: Louk Aourelien Andrianos, Edward Dommen, Athena Peralta
Abstract:
Greed, as epitomized by overconsumption of natural resources, is at the root of ecological destruction and unsustainability of modern societies. Presently economies rely on unrestricted structural greed which fuels unlimited economic growth, overconsumption, and individualistic competitive behavior. Structural greed undermines the life support system on earth and threatens ecological integrity, social justice and peace. The World Council of Churches (WCC) has developed a program on ecological and economic justice (EEJ) with the aim to promote an economy of life where the economy is embedded in society and society in ecology. This paper aims at analyzing and assessing the economy of life (EcoLife) by offering an empirical tool to measure and monitor the root causes and effects of unsustainability resulting from human greed on global, national, institutional and individual levels. This holistic approach is based on the integrity of ecology and economy in a society founded on justice. The paper will discuss critical questions such as ‘what is an economy of life’ and ‘how to measure and control it from the effect of greed’. A model called GLIMS, which stands for Greed Lines and Indices Measurement System is used to clarify the concept of greed and help measuring the economy of life index by fuzzy logic reasoning. The inputs of the model are from statistical indicators of natural resources consumption, financial realities, economic performance, social welfare and ethical and political facts. The outputs are concrete measures of three primary indices of ecological, economic and socio-political greed (ECOL-GI, ECON-GI, SOCI-GI) and one overall multidimensional economy of life index (EcoLife-I). EcoLife measurement aims to build awareness of an economy life and to address the effects of greed in systemic and structural aspects. It is a tool for ethical diagnosis and policy making.Keywords: greed line, sustainability indicators, fuzzy logic, eco-justice, World Council of Churches (WCC)
Procedia PDF Downloads 311915 Frailty Patterns in the US and Implications for Long-Term Care
Authors: Joelle Fong
Abstract:
Older persons are at greatest risk of becoming frail. As survival to the age of 80 and beyond continues to increase, the health and frailty of older Americans has garnered much recent attention among policy makers and healthcare administrators. This paper examines patterns in old-age frailty within a multistate actuarial model that characterizes the stochastic process of biological ageing. Using aggregate population-level U.S. mortality data, we implement a stochastic aging model to examine cohort trends and gender differences in frailty distributions for older Americans born 1865 – 1894. The stochastic ageing model, which draws from the fields of actuarial science and gerontology, is well-established in the literature. The implications for public health insurance programs are also discussed. Our results suggest that, on average, women tend to be frailer than men at older ages and reveal useful insights about the magnitude of the male-female differential at critical age points. Specifically, we note that the frailty statuses of males and females are actually quite comparable from ages 65 to 80. Beyond age 80, however, the frailty levels start to diverge considerably implying that women are moving quicker into worse states of health than men. Tracking average frailty by gender over 30 successive birth cohorts, we also find that frailty levels for both genders follow a distinct peak-and-trough pattern. For instance, frailty among 85-year old American survivors increased in years 1954-1963, decreased in years 1964-1971, and again started to increase in years 1972-1979. A number of factors may have accounted for these cohort differences including differences in cohort life histories, differences in disease prevalence, differences in lifestyle and behavior, differential access to medical advances, as well as changes in environmental risk factors over time. We conclude with a discussion on the implications of our findings on spending for long-term care programs within the broader health insurance system.Keywords: actuarial modeling, cohort analysis, frail elderly, health
Procedia PDF Downloads 237914 Performance of Reinforced Concrete Wall with Opening Using Analytical Model
Authors: Alaa Morsy, Youssef Ibrahim
Abstract:
Earthquake is one of the most catastrophic events, which makes enormous harm to properties and human lives. As a piece of a safe building configuration, reinforced concrete walls are given in structures to decrease horizontal displacements under seismic load. Shear walls are additionally used to oppose the horizontal loads that might be incited by the impact of wind. Reinforced concrete walls in residential buildings might have openings that are required for windows in outside walls or for doors in inside walls or different states of openings due to architectural purposes. The size, position, and area of openings may fluctuate from an engineering perspective. Shear walls can encounter harm around corners of entryways and windows because of advancement of stress concentration under the impact of vertical or horizontal loads. The openings cause a diminishing in shear wall capacity. It might have an unfavorable impact on the stiffness of reinforced concrete wall and on the seismic reaction of structures. Finite Element Method using software package ‘ANSYS ver. 12’ becomes an essential approach in analyzing civil engineering problems numerically. Now we can make various models with different parameters in short time by using ANSYS instead of doing it experimentally, which consumes a lot of time and money. Finite element modeling approach has been conducted to study the effect of opening shape, size and position in RC wall with different thicknesses under axial and lateral static loads. The proposed finite element approach has been verified with experimental programme conducted by the researchers and validated by their variables. A very good correlation has been observed between the model and experimental results including load capacity, failure mode, and lateral displacement. A parametric study is applied to investigate the effect of opening size, shape, position on different reinforced concrete wall thicknesses. The results may be useful for improving existing design models and to be applied in practice, as it satisfies both the architectural and the structural requirements.Keywords: Ansys, concrete walls, openings, out of plane behavior, seismic, shear wall
Procedia PDF Downloads 157913 An Overview of Suicidality in American Indians and Alaska Natives
Authors: Christopher S. Perez, Kendal C. Boyd
Abstract:
global suicide rates have decreased in recent decades, rates in the United States have increased by 35.2 percent since 1999.American Indians and Alaska Natives (AI/AN) have the highest rates of suicide in the U.S., with approximately 22 suicides per 100,000 people as of 2019. AI/AN have experienced significant historical trauma resulting in disproportionate rates of substance abuse and mental disorders. This literature review aimed to identify the demographic and clinical risk and protective factors for American Indians and Alaska Natives and provide an overview of suicidality in this population. The literature reflected varying definitions of suicidality depending on region, with some AI/AN tribesconceptualizing suicide through a spiritual framework, while others defined suicide in the biomedical sense. Furthermore, AI/AN adults and adolescents experienced higher rates of suicidal ideation when compared to other racial groups. Religious preference, sexual orientation, prior suicidal behavior, psychiatric admission, history of abuse, substance abuse, family history of mental illness, family history of substance abuse, family history of suicidal behaviors, domestic violence, and trauma were discussed as factors related to suicidality. Recommendations included increasing access to and utilization of mental health and medical services, culturally adapting suicide prevention programs to AI/AN communities, increasing support for LGBTQ+ AI/AN, providing opportunities that reinforce ethnic identity, and post-hospitalization follow-up care. The following databases were utilized to obtain peer-reviewed articles for this literature review: Complementary Index, Academic Search Premier, Science Direct, PsycInfo, Social Sciences Citation Index, PsycArticles, PubMed, EbscoHost, and PsycBooks. Articles that examined Native populations outside of the United States did not cite a primary source and/or were published before 1990 were excluded.Keywords: alaska native, american indian, protective factors, risk factors, suicidality, suicide
Procedia PDF Downloads 88