Search results for: rate of fertilizer application

Authors: Marcin Dębowski, Marcin Zieliński, Mirosław Krzemieniewski

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As methane fermentation is a complex series of successive biochemical transformations, its subsequent stages are determined, to a various extent, by physical and chemical factors. A specific state of equilibrium is being settled in the functioning fermentation system between environmental conditions and the rate of biochemical reactions and products of successive transformations. In the case of physical factors that influence the effectiveness of methane fermentation transformations, the key significance is ascribed to temperature and intensity of biomass agitation. Among the chemical factors, significant are pH value, type, and availability of the culture medium (to put it simply: the C/N ratio) as well as the presence of toxic substances. One of the important elements which influence the effectiveness of methane fermentation is the pre-treatment of organic substrates and the mode in which the organic matter is made available to anaerobes. Out of all known and described methods for organic substrate pre-treatment before methane fermentation process, the ultrasound disintegration is one of the most interesting technologies. Investigations undertaken on the ultrasound field and the use of installations operating on the existing systems result principally from very wide and universal technological possibilities offered by the sonication process. This physical factor may induce deep physicochemical changes in ultrasonicated substrates that are highly beneficial from the viewpoint of methane fermentation processes. In this case, special role is ascribed to disintegration of biomass that is further subjected to methane fermentation. Once cell walls are damaged, cytoplasm and cellular enzymes are released. The released substances – either in dissolved or colloidal form – are immediately available to anaerobic bacteria for biodegradation. To ensure the maximal release of organic matter from dead biomass cells, disintegration processes are aimed to achieve particle size below 50 μm. It has been demonstrated in many research works and in systems operating in the technical scale that immediately after substrate supersonication the content of organic matter (characterized by COD, BOD5 and TOC indices) was increasing in the dissolved phase of sedimentation water. This phenomenon points to the immediate sonolysis of solid substances contained in the biomass and to the release of cell material, and consequently to the intensification of the hydrolytic phase of fermentation. It results in a significant reduction of fermentation time and increased effectiveness of production of gaseous metabolites of anaerobic bacteria. Because disintegration of Virginia fanpetals biomass via ultrasounds applied in order to intensify its conversion is a novel technique, it is often underestimated by exploiters of agri-biogas works. It has, however, many advantages that have a direct impact on its technological and economical superiority over thus far applied methods of biomass conversion. As for now, ultrasound disintegrators for biomass conversion are not produced on the mass-scale, but by specialized groups in scientific or R&D centers. Therefore, their quality and effectiveness are to a large extent determined by their manufacturers’ knowledge and skills in the fields of acoustics and electronic engineering.

Keywords: ultrasound disintegration, biomass, methane fermentation, biogas, Virginia fanpetals

Procedia PDF Downloads 369

Authors: Luisa Kynast

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It is obvious that buildings and infrastructure are highly impacted by climate change (CC). Both, design and material of buildings need to be resilient to weather events in order to shelter humans, animals, or goods. As well as buildings and infrastructure are exposed to weather events, the construction process itself is generally carried out outdoors without being protected from extreme temperatures, heavy rain, or storms. The production process is restricted by technical limitations for processing materials with machines and physical limitations due to human beings (“outdoor-worker”). In future due to CC, average weather patterns are expected to change as well as extreme weather events are expected to occur more frequently and more intense and therefore have a greater impact on production processes and on the construction businesses itself. This research aims to examine this impact by analyzing an association between responses to CC and financial performance of businesses within the construction industry. After having embedded the above depicted field of research into the resource dependency theory, a literature review was conducted to expound the state of research concerning a contingent relation between climate change adaptation measures (CCAM) and corporate financial performance for construction businesses. The examined studies prove that this field is rarely investigated, especially for construction businesses. Therefore, reports of the Carbon Disclosure Project (CDP) were analyzed by applying content analysis using the software tool MAXQDA. 58 construction companies – located worldwide – could be examined. To proceed even more systematically a coding scheme analogous to findings in literature was adopted. Out of qualitative analysis, data was quantified and a regression analysis containing corporate financial data was conducted. The results gained stress adaptation measures as a response to CC as a crucial proxy to handle climate change impacts (CCI) by mitigating risks and exploiting opportunities. In CDP reports the majority of answers stated increasing costs/expenses as a result of implemented measures. A link to sales/revenue was rarely drawn. Though, CCAM were connected to increasing sales/revenues. Nevertheless, this presumption is supported by the results of the regression analysis where a positive effect of implemented CCAM on construction businesses´ financial performance in the short-run was ascertained. These findings do refer to appropriate responses in terms of the implemented number of CCAM. Anyhow, still businesses show a reluctant attitude for implementing CCAM, which was confirmed by findings in literature as well as by findings in CDP reports. Businesses mainly associate CCAM with costs and expenses rather than with an effect on their corporate financial performance. Mostly companies underrate the effect of CCI and overrate the costs and expenditures for the implementation of CCAM and completely neglect the pay-off. Therefore, this research shall create a basis for bringing CC to the (financial) attention of corporate decision-makers, especially within the construction industry.

Keywords: climate change adaptation measures, construction businesses, financial implication, resource dependency theory

Procedia PDF Downloads 145

Authors: Claudio Lamilla, Misael Riquelme, Victoria Saez, Fernanda Sepulveda, Monica Pavez, Leticia Barrientos

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Biosurfactants are compounds synthesized by microorganisms that show various chemical structures, including glycolipids, lipopeptides, polysaccharide-protein complex, phospholipids, and fatty acids. These molecules have attracted attention in recent years due to the amphipathic nature of these compounds, which allows their application in various activities related to emulsification, foaming, detergency, wetting, dispersion and solubilization of hydrophobic compounds. Microorganisms that produce biosurfactants are ubiquitous, not only present in water, soil, and sediments but in extreme conditions of pH, salinity or temperature such as those present in Antarctic ecosystems. Due to this, it is of interest to study biosurfactants producing bacterial strains isolated from Antarctic environments, with the potential to be used in various biotechnological processes. The objective of this research was to characterize biosurfactants produced by bacterial strains isolated from Antarctic environments, with potential use in biotechnological processes for the cleaning of sites contaminated with hydrocarbons. The samples were collected from soils and sediments in the South Shetland Islands and the Antarctic Peninsula, during the Antarctic Research Expedition INACH 2016, from both pristine and human occupied areas (influenced). The bacteria isolation was performed from solid R2A, M1 and LB media. The selection of strains producing biosurfactants was done by hemolysis test on blood agar plates (5%) and blue agar (CTAB). From 280 isolates, it was determined that 10 bacterial strains produced biosurfactants after stimulation with different carbon sources. 16S rDNA taxonomic markers, using the universal primers 27F-1492R, were used to identify these bacterias. Biosurfactants production was carried out in 250 ml flasks using Bushnell Hass liquid culture medium enriched with different carbon sources (olive oil, glucose, glycerol, and hexadecane) during seven days under constant stirring at 20°C. Each cell-free supernatant was characterized by physicochemical parameters including drop collapse, emulsification and oil displacement, as well as stability at different temperatures, salinity, and pH. In addition, the surface tension of each supernatant was quantified using a tensiometer. The strains with the highest activity were selected, and the production of biosurfactants was stimulated in six liters of culture medium. Biosurfactants were extracted from the supernatants with chloroform methanol (2:1). These biosurfactants were tested against crude oil and motor oil, to evaluate their displacement activity (detergency). The characterization by physicochemical properties of 10 supernatants showed that 80% of them produced the drop collapse, 60% had stability at different temperatures, and 90% had detergency activity in motor and olive oil. The biosurfactants obtained from two bacterial strains showed a high activity of dispersion of crude oil and motor oil with halos superior to 10 cm. We can conclude that bacteria isolated from Antarctic soils and sediments provide biological material of high quality for the production of biosurfactants, with potential applications in the biotechnological industry, especially in hydrocarbons -contaminated areas such as petroleum.

Keywords: antarctic, bacteria, biosurfactants, hydrocarbons

Procedia PDF Downloads 279

Authors: Nivedita T. Patil, M. T. Patil, M. S. Shashidhar, R. G. Gonnade

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Cyclitols are cycloalkane polyols which have raise attention since they have numerous biological and pharmaceutical properties. Among these, inositols are important cyclitols, which constitute a group of naturally occurring polyhydric alcohols. Myo, scyllo, allo, neo, D-chiro- are naturally occurring structural isomer of inositol while other four isomers (L-chiro, allo, epi-, and cis-inositol) are derived from myo-inositol by chemical synthesis. Myo-inositol, most abundant isomer, plays an important role in signal transduction process and for the treatment of type 2 diabetes, bacterial infections, stimulation of menstruation, ovulation in polycystic ovary syndrome, improvement of osteogenesis, and in treatment of neurological disorders. Considering the vast application of the derivatives, it becomes important to supply these compounds for further studies in quantitative amounts, but the synthesis of suitably protected chiral inositol derivatives is the key intermediates in most of the synthesis which is difficult. Chiral inositol derivatives could also be of interest to synthetic organic chemists as they could serve as potential starting materials for the synthesis of several natural products and their analogs. Thus, obtaining chiral myo-inositol derivatives in a more eco-friendly way is need for current inositol chemistry. Thus, the resolution of nonracemates by preferential crystallization of enantiomers has not been reported as a method for inositol derivatives. We are optimistic that this work might lead to the development of the two tosylate enantiomers as synthetic chiral pool molecules for organic synthesis. Resolution of racemic 4-O-benzyl 6-O-tosyl myo-inositol 1, 3, 5 orthoformate was successfully achieved on multigram scale by preferential crystallization, which is more scalable, eco-friendly method of separation than other reported methods. The separation of the conglomeric mixture of tosylate was achieved by suspending the mixture in ethyl acetate till the level of saturation is obtained. To this saturated clear solution was added seed crystal of the desired enantiomers. The filtration of the precipitated seed was carried out at its filtration window to get enantiomerically enriched tosylate, and the process was repeated alternatively. These enantiomerically enriched samples were recrystallized to get tosylate as pure enantiomers. The configuration of the resolved enantiomers was determined by converting it to previously reported dibenzyl ether myo-inositol, which is an important precursor for mono- and tetraphosphates. We have also developed a convenient and practical method for the preparation of enantiomeric 4-O and 6-O-allyl myo-inositol orthoesters by resolution of diastereomeric allyl dicamphante orthoesters on multigram scale. These allyl ethers can be converted to other chiral protected myo-inositol derivatives using routine synthetic transformations. The chiral allyl ethers can be obtained in gram quantities, and the methods are amenable to further scale-up due to the simple procedures involved. We believe that the work described enhances the pace of research to understand the intricacies of the myo-inositol cycle as the methods described provide efficient access to enantiomeric phosphoinositols, cyclitols, and their derivatives from the abundantly available myo-inositol as a starting material.

Keywords: cyclitols, diastereomers, enantiomers, myo-inositol, preferential crystallization, signal transduction

Procedia PDF Downloads 142

Authors: Mohammed Alhamed

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This research examines the factors influencing the acceptance and adoption of digital technologies in Saudi Arabia’s government sector by focusing on government employees' attitudes toward digital transformation initiatives. As digital technologies increasingly integrate into public sectors worldwide, there is a requirement to enhance citizen empowerment and government-public interactions as well as understand their impact in unique socio-political contexts like Saudi Arabia. The study aims to explore user attitudes, identify the main challenges, and investigate factors that affect the intention to use digital applications in governmental settings. The study employs a mixed-methods approach by combining quantitative and qualitative data collection to provide a comprehensive view of digital government application adoption. Data was collected through two online surveys administered to 870 government employees and face-to-face semi-structured interviews with 24 participants. This dual approach allows for both statistical analysis and thematic exploration, which provides a deeper understanding of user behaviour, perceived benefits, challenges and attitudes toward these digital applications. Quantitative data were analyzed to identify significant variables influencing adoption, while qualitative responses were coded thematically to uncover recurring themes related to user trust, security, usability and socio-political influences. The results indicate that digital government applications are largely valued for their ability to increase efficiency and accessibility and streamline processes like online documentation and inter-departmental coordination. However, the study highlights that security, privacy, and confidentiality concerns constitute substantial barriers to adoption, with participants calling for stronger cybersecurity measures and data protection policies. Moreover, usability emerged as a key theme that intuitively interfaces in encouraging adoption as respondents emphasized the importance of user-friendly. Additionally, the study found that Saudi Arabia’s unique cultural and organizational dynamics impact acceptance levels with factors like hierarchical structures and varying levels of digital literacy shaping user attitudes. A significant limitation of the study is its exclusive focus on government employees, which may limit the generalizability of the findings to other stakeholder groups, such as the general public. Despite this, the study offers valuable views for policymakers. This, in turn, suggests best practices and guidelines that could enhance the design and implementation of digital government projects. By addressing the identified barriers and leveraging the factors that drive adoption, the study underscores the potential for digital government initiatives to improve efficiency, transparency and responsiveness in Saudi Arabia's public sector. Furthermore, these findings may provide a roadmap for similar countries aiming to adopt digital government solutions within comparable socio-political and economic contexts.

Keywords: acceptance, adoption, digital technologies, digital government, Saudi Arabia

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Authors: M. Golam Rabbi

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Theme of wildlife crime is unique in Bangladesh. In earlier of 2010, wildlife crime was not designated as a crime, unlike other offenses. Forest Department and other enforcement agencies were not in full swing to find out the organized crime scene at that time and recorded few cases along with forest crime. However, after the establishment of Wildlife Crime Control Unitin 2012a, total of 374 offenses have been detected with 566 offenders and 37,039 wildlife and trophies were seized till November 2016. Most offenses seem to be committed outside the forests where the presence of the forest staff is minimal. Total detection percentage of offenses is not known, but offenders are not identified in 60% of detected cases (UDOR). Only 20% cases are decided by the courts even after eight years, conviction rate of the total disposal is 70.65%. Mostly six months imprisonment and BDT 5000 fine seems to be the modal penalty. The monetary value of wildlife crime in the country is approximate $0.72M per year and the maximum value counted for reptiles around $0.45M especially for high-level trafficking of geckos and turtles. The most common seizures of wildlife are birds (mynas, munias, parakeets, lorikeets, water birds, etc.) which have domestic demand for pet. Some other wildlife like turtles, lizards and small mammals are also on the list. Venison and migratory waterbirds often seized which has a large quantity demand for consuming at aristocratic level.Due to porous border and weak enforcement in border region poachers use the way for trafficking of geckos, turtles, and tortoises, snakes, venom, tiger and body parts, spotted deerskin, pangolinetc. Those have very high demand in East Asian countries for so-called medicinal purposes. The recent survey also demonstrates new route for illegal trade and trafficking for instance, after poaching of tiger and deer from the Sundarbans, the largest mangrove track of the planet to Thailand through the Bay of Bengal, sharks fins and ray fish through Chittagong seaport and directly by sea routes to Myanmar and Thailand. However, a good number of records of offense demonstrate the transition route from India to South and South East Asian countries. Star tortoises and Hamilton’s turtles are smuggled in from India which mostly seized at Benapole border of Jessore and Hazrat Shah Jajal International Airport of Dhaka, in very large numbers for transmission to East Asian countries. Most of the cases of wildlife trade routes leading to China, Thailand, Malaysia, and Myanmar. Most surprisingly African ivory was seized in Bangladesh recently, which was meant to be trafficked to the South-East Asia. However; forest department is working to fight against wildlife poaching, illegal trade and trafficking in collaboration with other law enforcement agencies. The department needs a clear mandate and to build technical capabilities for identifying, seizing and holding specimens. The department also needs to step out of the forests and must develop the capacity to surveillance and patrol all sensitive locations across the country.

Keywords: Bangladesh forest department, Sundarban, tiger, wildlife crime, wildlife trafficking

Procedia PDF Downloads 308

Authors: Cristina Opris, Bogdan Cojocaru, Madalina Tudorache, Simona M. Coman, Vasile I. Parvulescu, Camelia Bala, Bahir Duraki, Jeroen A. Van Bokhoven

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The tremendous achievements in the development of the society concretized by more sophisticated materials and systems are merely based on non-renewable resources. Consequently, after more than two centuries of intensive development, among others, we are faced with the decrease of the fossil fuel reserves, an increased impact of the greenhouse gases on the environment, and economic effects caused by the fluctuations in oil and mineral resource prices. The use of biomass may solve part of these problems, and recent analyses demonstrated that from the perspective of the reduction of the emissions of carbon dioxide, its valorization may bring important advantages conditioned by the usage of genetic modified fast growing trees or wastes, as primary sources. In this context, the abundance and complex structure of lignin may offer various possibilities of exploitation. However, its transformation in fuels or chemicals supposes a complex chemistry involving the cleavage of C-O and C-C bonds and altering of the functional groups. Chemistry offered various solutions in this sense. However, despite the intense work, there are still many drawbacks limiting the industrial application. Thus, the proposed technologies considered mainly homogeneous catalysts meaning expensive noble metals based systems that are hard to be recovered at the end of the reaction. Also, the reactions were carried out in organic solvents that are not acceptable today from the environmental point of view. To avoid these problems, the concept of this work was to investigate the synthesis of superparamagnetic core shell catalysts for the fragmentation of lignin directly in the aqueous phase. The magnetic nanoparticles were covered with a nanoshell of an oxide (niobia) with a double role: to protect the magnetic nanoparticles and to generate a proper (acidic) catalytic function and, on this composite, cobalt nanoparticles were deposed in order to catalyze the C-C bond splitting. With this purpose, we developed a protocol to prepare multifunctional and magnetic separable nano-composite Co@Nb2O5@Fe3O4 catalysts. We have also established an analytic protocol for the identification and quantification of the fragments resulted from lignin depolymerization in both liquid and solid phase. The fragmentation of various lignins occurred on the prepared materials in high yields and with very good selectivity in the desired fragments. The optimization of the catalyst composition indicated a cobalt loading of 4wt% as optimal. Working at 180 oC and 10 atm H2 this catalyst allowed a conversion of lignin up to 60% leading to a mixture containing over 96% in C20-C28 and C29-C37 fragments that were then completely fragmented to C12-C16 in a second stage. The investigated catalysts were completely recyclable, and no leaching of the elements included in the composition was determined by inductively coupled plasma optical emission spectrometry (ICP-OES).

Keywords: superparamagnetic core-shell catalysts, environmental production of fuels, renewable lignin, recyclable catalysts

Procedia PDF Downloads 329

Authors: A. Abubakar, A. Parsa, S. Walker

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Despite advances made in the diagnosis and management of drug-sensitive tuberculosis (TB) over the past decades, treatment of multidrug-resistant tuberculosis (MDR-TB) remains challenging and complex particularly in high burden countries including Nigeria. Treatment of MDR-TB is cost-prohibitive with success rate generally lower compared to drug-sensitive TB and if care is not taken it may become the dominant form of TB in future with many treatment uncertainties and substantial morbidity and mortality. Addressing these challenges requires collaborative efforts thorough sustained researches to evaluate the current treatment guidelines, particularly in high burden countries and prevent progression of resistance. To our best knowledge, there has been no research exploring the acceptability, effectiveness, and cost-effectiveness of community-based-MDR-TB treatment model in Nigeria, which is among the high burden countries. The previous similar qualitative study looks at the home-based management of MDR-TB in rural Uganda. This research aimed to explore patient’s views and acceptability of community-based-MDR-TB treatment model and to evaluate and compare the effectiveness and cost-effectiveness of community-based versus hospital-based MDR-TB treatment model of care from the Nigerian perspective. Knowledge of patient’s views and acceptability of community-based-MDR-TB treatment approach would help in designing future treatment recommendations and in health policymaking. Accordingly, knowledge of effectiveness and cost-effectiveness are part of the evidence needed to inform a decision about whether and how to scale up MDR-TB treatment, particularly in a poor resource setting with limited knowledge of TB. Mixed methods using qualitative and quantitative approach were employed. Qualitative data were obtained using in-depth semi-structured interviews with 21 MDR-TB patients in Nigeria to explore their views and acceptability of community-based MDR-TB treatment model. Qualitative data collection followed an iterative process which allowed adaptation of topic guides until data saturation. In-depth interviews were analyzed using thematic analysis. Quantitative data on treatment outcomes were obtained from medical records of MDR-TB patients to determine the effectiveness and direct and indirect costs were obtained from the patients using validated questionnaire and health system costs from the donor agencies to determine the cost-effectiveness difference between community and hospital-based model from the Nigerian perspective. Findings: Some themes have emerged from the patient’s perspectives indicating preference and high acceptability of community-based-MDR-TB treatment model by the patients and mixed feelings about the risk of MDR-TB transmission within the community due to poor infection control. The result of the modeling from the quantitative data is still on course. Community-based MDR-TB care was seen as the acceptable and most preferred model of care by the majority of the participants because of its convenience which in turn enhanced recovery, enables social interaction and offer more psychosocial benefits as well as averted productivity loss. However, there is a need to strengthen this model of care thorough enhanced strategies that ensure guidelines compliance and infection control in order to prevent the progression of resistance and curtail community transmission.

Keywords: acceptability, cost-effectiveness, multidrug-resistant TB treatment, community and hospital approach

Procedia PDF Downloads 123

Authors: Catherine McWhorter

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Robotics is a fast-evolving field lacking comprehensive and harm-mitigating regulation; it also lacks critical data on how human-robot interaction (HRI) may affect human psychology. As most anthropomorphic robots are intended as substitutes for humans, this paper asserts that the commercial robotics industry should be preemptively regulated at the federal level such that robots capable of embodying a victim role in criminal scenarios (“vicbots”) are prohibited until clinical studies determine their effects on the user and society. The results of these studies should then inform more permanent legislation that strives to mitigate risks of harm without infringing upon fundamental rights or stifling innovation. This paper explores these concepts through the lens of the sex robot industry. The sexbot industry offers some of the most realistic, interactive, and customizable robots for sale today. From approximately 2010 until 2017, some sex robot producers, such as True Companion, actively promoted ‘vicbot’ culture with personalities like “Frigid Farrah” and “Young Yoko” but received significant public backlash for fetishizing rape and pedophilia. Today, “Frigid Farrah” and “Young Yoko” appear to have vanished. Sexbot producers have replaced preprogrammed vicbot personalities in favor of one generic, customizable personality. According to the manufacturer ainidoll.com, when asked, there is only one thing the user won’t be able to program the sexbot to do – “…give you drama”. The ability to customize vicbot personas is possible with today’s generic personality sexbots and may undermine the intent of some current legislative efforts. Current debate on the effects of vicbots indicates a lack of consensus. Some scholars suggest vicbots may reduce the rate of actual sex crimes, and some suggest that vicbots will, in fact, create sex criminals, while others cite their potential for rehabilitation. Vicbots may have value in some instances when prescribed by medical professionals, but the overall uncertainty and lack of data further underscore the need for preemptive regulation and clinical research. Existing literature on exposure to media violence and its effects on prosocial behavior, human aggression, and addiction may serve as launch points for specific studies into the hyperrealism of vicbots. Of course, the customization, anthropomorphism and artificial intelligence of sexbots, and therefore more mainstream robots, will continue to evolve. The existing sexbot industry offers an opportunity to preemptively regulate and to research answers to these and many more questions before this type of technology becomes even more advanced and mainstream. Robots pose complicated moral, ethical, and legal challenges, most of which are beyond the scope of this paper. By examining the possibility for custom vicbots via the sexbots industry, reviewing existing literature on regulation, media violence, and vicbot user effects, this paper strives to underscore the need for preemptive federal regulation prohibiting vicbot capabilities in robots while advocating for further research into the potential for the user and societal harm by the same.

Keywords: human-robot interaction effects, regulation, research, robots

Procedia PDF Downloads 207

Authors: Sandhya Rijal, Saroj Adhikari, Ramesh R. Pant

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Non-Timber Forest Products (NTFPs) have attracted substantial interest in the recent years with the increasing recognition that these can provide essential community needs for improved and diversified rural livelihood and support the objectives of biodiversity conservation. Nevertheless, various challenges are witnessed in their sustainable harvest and management. Assuming that sustainable management with community stewardship can offer one of the solutions to existing challenges, the study assesses the linkages between NTFPs and rural livelihood in Lamabagar village of Dolakha, Nepal. The major objective was to document the status of NTFPs and their contributions in households of Lamabagar. For status documentation, vegetation sampling was done using systematic random sampling technique. 30 plots of 10 m × 10 m were laid down in six parallel transect lines at horizontal distance of 160 m in two different community forests. A structured questionnaire survey was conducted in 76 households (excluding non-response rate) using stratified random sampling technique for contribution analysis. Likewise, key informant interview and focus group discussions were also conducted for data triangulations. 36 different NTFPs were recorded from the vegetation sample in two community forests of which 50% were used for medicinal purposes. The other uses include fodder, religious value, and edible fruits and vegetables. Species like Juniperus indica, Daphne bholua Aconitum spicatum, and Lyonia ovalifolia were frequently used for trade as a source of income, which was sold in local market. The protected species like Taxus wallichiana and Neopicrorhiza scrophulariiflora were also recorded in the area for which the trade is prohibited. The protection of these species urgently needs community stewardship. More than half of the surveyed households (55%) were depending on NTFPs for their daily uses, other than economic purpose whereas 45% of them sold those products in the market directly or in the form of local handmade products as a source of livelihood. NTFPs were the major source of primary health curing agents especially for the poor and unemployed people in the study area. Hence, the NTFPs contributed to livelihood under three different categories: subsistence, supplement income and emergency support, depending upon the economic status of the households. Although the status of forest improved after handover to the user group, the availability of valuable medicinal herbs like Rhododendron anthopogon, Swertia nervosa, Neopicrorhiza scrophulariiflora, and Aconitum spicatum were declining. Inadequacy of technology, lack of easy transport access, and absence of good market facility were the major limitations for external trade of NTFPs in the study site. It was observed that people were interested towards conservation only if they could get some returns: economic in terms of rural settlements. Thus, the study concludes that NTFPs could contribute rural livelihood and support conservation objectives only if local communities are provided with the easy access of technology, market and capital.

Keywords: contribution, medicinal, subsistence, sustainable harvest

Procedia PDF Downloads 127

Authors: Brenagh E. Schlingermann, Clare Lodge, Paula Rankin

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Background: Gaelic football, hurling and camogie are highly popular field games in Ireland. Research into the epidemiology of injury in Gaelic games revealed that approximately three quarters of the injuries in the games occur in the lower extremity. These injuries can have player, team and institutional impacts due to multiple factors including financial burden and time loss from competition. Research has shown it is possible to record injury data consistently with the GAA through a closed online recording system known as the GAA injury surveillance database. It has been established that determining the incidence of injury is the first step of injury prevention. The goals of this study were to create a dynamic GAA15 injury prevention programme which addressed five key components/goals; avoid positions associated with a high risk of injury, enhance flexibility, enhance strength, optimize plyometrics and address sports specific agilities. These key components are internationally recognized through the Prevent Injury, Enhance performance (PEP) programme which has proven reductions in ACL injuries by 74%. In national Gaelic games the programme is known as the GAA15 which has been devised from the principles of the PEP. No such injury prevention strategies have been published on this cohort in Gaelic games to date. This study will investigate the effects of the GAA15 on injury incidence and neuromuscular function in Gaelic games. Methods: A total of 154 players (mean age 20.32 ± 2.84) were recruited from the GAA teams within the Institute of Technology Carlow (ITC). Preseason and post season testing involved two objective screening tests; Y balance test and Three Hop Test. Practical workshops, with ongoing liaison, were provided to the coaches on the implementation of the GAA15. The programme was performed before every training session and game and the existing GAA injury surveillance database was accessed to monitor player’s injuries by the college sports rehabilitation athletic therapist. Retrospective analysis of the ITC clinic records were performed in conjunction with the database analysis as a means of tracking injuries that may have been missed. The effects of the programme were analysed by comparing the intervention groups Y balance and three hop test scores to an age/gender matched control group. Results: Year 1 results revealed significant increases in neuromuscular function as a result of the GAA15. Y Balance test scores for the intervention group increased in both the posterolateral (p=.005 and p=.001) and posteromedial reach directions (p= .001 and p=.001). A decrease in performance was determined for the three hop test (p=.039). Overall twenty-five injuries were reported during the season resulting in an injury rate of 3.00 injuries/1000hrs of participation; 1.25 injuries/1000hrs training and 4.25 injuries/1000hrs match play. Non-contact injuries accounted for 40% of the injuries sustained. Year 2 results are pending and expected April 2016. Conclusion: It is envisaged that implementation of the GAA15 will continue to reduce the risk of injury and improve neuromuscular function in collegiate Gaelic games athletes.

Keywords: GAA15, Gaelic games, injury prevention, neuromuscular training

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Authors: Lilah Inzelberg, David Rand, Stanislav Steinberg, Moshe David Pur, Yael Hanein

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Human facial expressions carry important psychological and neurological information. Facial expressions involve the co-activation of diverse muscles. They depend strongly on personal affective interpretation and on social context and vary between spontaneous and voluntary activations. Smiling, as a special case, is among the most complex facial emotional expressions, involving no fewer than 7 different unilateral muscles. Despite their ubiquitous nature, smiles remain an elusive and debated topic. Smiles are associated with happiness and greeting on one hand and anger or disgust-masking on the other. Accordingly, while high-resolution recording of muscle activation patterns, in a non-interfering setting, offers exciting opportunities, it remains an unmet challenge, as contemporary surface facial electromyography (EMG) methodologies are cumbersome, restricted to the laboratory settings, and are limited in time and resolution. Here we present a wearable and non-invasive method for objective mapping of facial muscle activation and demonstrate its application in a natural setting. The technology is based on a recently developed dry and soft electrode array, specially designed for surface facial EMG technique. Eighteen healthy volunteers (31.58 ± 3.41 years, 13 females), participated in the study. Surface EMG arrays were adhered to participant left and right cheeks. Participants were instructed to imitate three facial expressions: closing the eyes, wrinkling the nose and smiling voluntary and to watch a funny video while their EMG signal is recorded. We focused on muscles associated with 'enjoyment', 'social' and 'masked' smiles; three categories with distinct social meanings. We developed a customized independent component analysis algorithm to construct the desired facial musculature mapping. First, identification of the Orbicularis oculi and the Levator labii superioris muscles was demonstrated from voluntary expressions. Second, recordings of voluntary and spontaneous smiles were used to locate the Zygomaticus major muscle activated in Duchenne and non-Duchenne smiles. Finally, recording with a wireless device in an unmodified natural work setting revealed expressions of neutral, positive and negative emotions in face-to-face interaction. The algorithm outlined here identifies the activation sources in a subject-specific manner, insensitive to electrode placement and anatomical diversity. Our high-resolution and cross-talk free mapping performances, along with excellent user convenience, open new opportunities for affective processing and objective evaluation of facial expressivity, objective psychological and neurological assessment as well as gaming, virtual reality, bio-feedback and brain-machine interface applications.

Keywords: affective expressions, affective processing, facial EMG, high-resolution electromyography, independent component analysis, wireless electrodes

Procedia PDF Downloads 247

Authors: Rachid Belhachemi, Pierre Rostan, Alexandra Rostan

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This paper develops a discrete-time option pricing model for index options. The model consists of two key ingredients. First, daily stock return innovations are driven by a continuous hidden threshold mixed skew-normal (HTSN) distribution which generates conditional non-normality that is needed to fit daily index return. The most important feature of the HTSN is the inclusion of a latent state variable with a continuum of states, unlike the traditional mixture distributions where the state variable is discrete with little number of states. The HTSN distribution belongs to the class of univariate probability distributions where parameters of the distribution capture the dependence between the variable of interest and the continuous latent state variable (the regime). The distribution has an interpretation in terms of a mixture distribution with time-varying mixing probabilities. It has been shown empirically that this distribution outperforms its main competitor, the mixed normal (MN) distribution, in terms of capturing the stylized facts known for stock returns, namely, volatility clustering, leverage effect, skewness, kurtosis and regime dependence. Second, heteroscedasticity in the model is captured by a threeexogenous-factor GARCH model (GARCHX), where the factors are taken from the principal components analysis of various world indices and presents an application to option pricing. The factors of the GARCHX model are extracted from a matrix of world indices applying principal component analysis (PCA). The empirically determined factors are uncorrelated and represent truly different common components driving the returns. Both factors and the eight parameters inherent to the HTSN distribution aim at capturing the impact of the state of the economy on price levels since distribution parameters have economic interpretations in terms of conditional volatilities and correlations of the returns with the hidden continuous state. The PCA identifies statistically independent factors affecting the random evolution of a given pool of assets -in our paper a pool of international stock indices- and sorting them by order of relative importance. The PCA computes a historical cross asset covariance matrix and identifies principal components representing independent factors. In our paper, factors are used to calibrate the HTSN-GARCHX model and are ultimately responsible for the nature of the distribution of random variables being generated. We benchmark our model to the MN-GARCHX model following the same PCA methodology and the standard Black-Scholes model. We show that our model outperforms the benchmark in terms of RMSE in dollar losses for put and call options, which in turn outperforms the analytical Black-Scholes by capturing the stylized facts known for index returns, namely, volatility clustering, leverage effect, skewness, kurtosis and regime dependence.

Keywords: continuous hidden threshold, factor models, GARCHX models, option pricing, risk-premium

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Authors: Kiran Baldavoo, Mishelle Doorasamy

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Universities have a role to play in the preservation of the environment, and the study attempted to evaluate the environmental management accounting (EMA) processes at UKZN. UKZN, a South African university, generates the same direct and indirect environmental impacts as the higher education sector worldwide. This is significant within the context of the South African environment which is constantly plagued by having to effectively manage the already scarce resources of water and energy, evident through the imposition of water and energy restrictions over the recent years. The study’s aim is to increase awareness of having a structured approach to environmental management in order to achieve the strategic environmental goals of the university. The research studied the experiences of key managers within UKZN, with the purpose of exploring the potential factors which influence the decision to adopt and apply EMA within the higher education sector. The study comprised two objectives, namely understanding the current state of accounting practices for managing major environmental costs and identifying factors influencing EMA adoption within the university. The study adopted a case study approach, comprising semi-structured interviews of key personnel involved in Management Accounting, Environmental Management, and Academic Schools within the university. Content analysis was performed on the transcribed interview data. A Theoretical Framework derived from literature was adopted to guide data collection and focus the study. Contingency and Institutional theory was the resultant basis of the derived framework. The findings of the first objective revealed that there was a distinct lack of EMA utilization within the university. There was no distinct policy on EMA, resulting in minimal environmental cost information being brought to the attention of senior management. The university embraced the principles of environmental sustainability; however, efforts to improve internal environmental accountability primarily from an accounting perspective was absent. The findings of the second objective revealed that five key barriers contributed to the lack of EMA utilization within the university. The barriers being attitudinal, informational, institutional, technological, and lack of incentives (financial). The results and findings of this study supported the use and application of EMA within the higher education sector. Participants concurred that EMA was underutilized and if implemented, would realize significant benefits for both the university and environment. Environmental management accounting is being widely acknowledged as a key management tool that can facilitate improved financial and environmental performance via the concept of enhanced environmental accountability. Historically research has been concentrated primarily on the manufacturing industry, due to it generating the greatest proportion of environmental impacts. Service industries are also an integral component of environmental management as they contribute significant environmental impacts, both direct and indirect. Educational institutions such as universities form part of the service sector and directly impact on the environment through the consumption of paper, energy, and water and solid waste generated, with the associated demands.

Keywords: environmental management accounting, environmental impacts, higher education, Southern Africa

Procedia PDF Downloads 125

Authors: Hafsa Memona, Farkhanda Manzoor

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Cockroaches are termed as medically important pests because of their wide distribution in human habitation including houses, hospitals, food industries and kitchens. They may harbor multiple drug resistant pathogenic bacteria and protozoan parasites on their external surfaces, disseminate on human food and cause serious diseases and allergies to human. Hence, they are regarded as mechanical vector in human habitation due to their nocturnal activity and nutritional behavior. Viable eggs and dormant cysts of parasites can hitch a ride on cockroaches. Ova and cysts of parasitic organism may settle into the crevices and cracks between thorax and head. There are so many fissures and clefts and crannies on a cockroach which provide site for these organisms. This study aimed with identifying role of cockroaches in mechanically transmitting and disseminating gastrointestinal parasites in two environmental settings; hospitals and houses in urban area of Lahore. Totally, 250 adult cockroaches were collected from houses and hospitals by sticky traps and food baited traps and screened for parasitic load. All cockroaches were captured during their feeding time in natural habitat. Direct wet smear, 1% lugols iodine and modified acid-fast bacilli staining were used to identify the parasites from the body surfaces of cockroaches. Among human habitation two common species of cockroaches were collected i.e. P. americana and B. germanica. The results showed that 112 (46.8%) cockroaches harbored at least one human intestinal parasite on their body surfaces. The cockroaches from hospital environment harboured more parasites than houses. 47 (33.57%) cockroaches from houses and 65 (59.09%) from hospitals were infected with parasitic organisms. Of these, 76 (67.85%) were parasitic protozoans and 36(32.15%) were pathogenic and non-pathogenic intestinal parasites. P. americana harboured more parasites as compared to B. germanica in both environment. Most common human intestinal parasites found on cockroaches include ova of Ascaris lumbricoides (giant roundworm), Trichuris trichura (whipworm), Anchylostoma deodunalae (hookworm), Enterobius vermicularis (pinworm), Taenia spp. and Strongyloides stercoralis (threadworm). The cysts of protozoans’ parasites including Balantidium coli, Entomoeba hystolitica, C. parvum, Isospora belli, Giardia duodenalis and C. cayetenensis were isolated and identified from cockroaches. Both experimental sites were significantly different in carriage of parasitic load on cockroaches. Difference in the hygienic condition of the environments, including human excrement disposal, variable habitat interacted, indoor and outdoor species, may account for the observed variation in the parasitic carriage rate of cockroaches among different experimental site. Thus a finding of this study is that Cockroaches are uniformly distributed in human habitation and act as a mechanical vector of pathogenic parasites that cause common illness such as diarrhea and bowel disorders. This fact contributes to epidemiological chain therefore control of cockroaches will significantly lessen the prevalence of illness in human. Effective control strategies will reduce the public health burden of the gastro-intestinal parasites in the developing countries.

Keywords: cockroaches, health risks, hospitals, houses, parasites, protozoans, transmission

Procedia PDF Downloads 282

Authors: Cristina Diaz, Lucia Perez, Simone Visigalli, Giuseppe Di Florio, Gonzalo Fuentes, Roberto Canziani, Paolo Gronchi

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During the last 50 years, the selection of materials is one of the main decisions in machine design for different industrial applications. It is due to numerous physical, chemical, mechanical and technological factors to consider in it. Corrosion effects are related with all of these factors and impact in the life cycle, machine incidences and the costs for the life of the machine. Corrosion affects the deterioration or destruction of metals due to the reaction with the environment, generally wet. In food industry, dewatering industry, concrete industry, paper industry, etc. corrosion is an unsolved problem and it might introduce some alterations of some characteristics in the final product. Nowadays, depending on the selected metal, its surface and its environment of work, corrosion prevention might be a change of metal, use a coating, cathodic protection, use of corrosion inhibitors, etc. In the vast majority of the situations, use of a corrosion resistant material or in its defect, a corrosion protection coating is the solution. Stainless steels are widely used in machine design, because of their strength, easily cleaned capacity, corrosion resistance and appearance. Typical used are AISI 304 and AISI 316. However, their benefits don’t fit every application, and some coatings are required against corrosion such as some paintings, galvanizing, chrome plating, SiO₂, TiO₂ or ZrO₂ coatings, etc. In this work, some coatings based in a bilayer made of Titanium-Tantalum, Titanium-Niobium, Titanium-Hafnium or Titanium-Zirconium, have been developed used magnetron sputtering configuration by PVD (Physical Vapor Deposition) technology, for trying to reduce corrosion effects on AISI 304, AISI 316 and comparing it with Titanium alloy substrates. Ti alloy display exceptional corrosion resistance to chlorides, sour and oxidising acidic media and seawater. In this study, Ti alloy (99%) has been included for comparison with coated AISI 304 and AISI 316 stainless steel. Corrosion tests were conducted by a Gamry Instrument under ASTM G5-94 standard, using different electrolytes such as tomato salsa, wine, olive oil, wet compost, a mix of sand and concrete with water and NaCl for testing corrosion in different industrial environments. In general, in all tested environments, the results showed an improvement of corrosion resistance of all coated AISI 304 and AISI 316 stainless steel substrates when they were compared to uncoated stainless steel substrates. After that, comparing these results with corrosion studies on uncoated Ti alloy substrate, it was observed that in some cases, coated stainless steel substrates, reached similar current density that uncoated Ti alloy. Moreover, Titanium-Zirconium and Titanium-Tantalum coatings showed for all substrates in study including coated Ti alloy substrates, a reduction in current density more than two order in magnitude. As conclusion, Ti-Ta, Ti-Zr, Ti-Nb and Ti-Hf coatings have been developed for improving corrosion resistance of AISI 304 and AISI 316 materials. After corrosion tests in several industry environments, substrates have shown improvements on corrosion resistance. Similar processes have been carried out in Ti alloy (99%) substrates. Coated AISI 304 and AISI 316 stainless steel, might reach similar corrosion protection on the surface than uncoated Ti alloy (99%). Moreover, coated Ti Alloy (99%) might increase its corrosion resistance using these coatings.

Keywords: coatings, corrosion, PVD, stainless steel

Procedia PDF Downloads 158

Authors: Özgür Bahadir, Meltem Kurtuncu

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The study was designed as quasi-experimental and conducted to determine the effect of music therapy on anxiety, fear and pain management in 6-12-year-old children undergoing surgery. The present study was carried out between 01.01.2016 and 19.08.2016 in BEU. Application and Research Center. The children aged 6 -12 who applied for surgery between the mentioned dates constituted the universe of the study. In the quasi-experimental study that was conducted in the clinics where children received operational treatment, two groups were formed: experimental group (the children who received musical therapy before the surgery) and control group (the children who were administered surveys and the surgery service routines only). Each group consisted of 30 children, and the participants of the study were 60 children in total. Necessary permissions were obtained from the parents of the children hospitalized before the beginning of the implementation. The data was collected through Child Anxiety Sensitivity Index (CASI), “Fear In Medical Treatment Scale”, Face, Legs, Activity, Cry, Consolability Scale (FLACC), Visual Analog Scale (VAS) and Participant Information Form. In the analysis of the data, Kolmogorov-Smirnov distribution scale was used to examine the normality of the distribution along with descriptive statistics methods (Frequency, Percentage, Mean, Standard Deviation). Data was presented in the tables in numbers and percentages. Means were demonstrated along with the standard deviations. The research compared children received; case and control groups include socio-demographic perspective, non-significant difference statistically among similar groups are intertwined. The general level of fear regarding the medical processes before returning to service after the operation and 30 minutes before getting discharged was found to be significantly low in the experimental group compared to control group (p<0.05). No statistically significant difference was found between experimental and control groups in terms of general level of fear regarding the medical processes before the operation, during the operation day and in the recovery room after the operation (p>0.05). Total CASI AD (anxiety sensitivity) levels before the operation, day of the operation and 30 minutes before the discharge for patients in experimental group was found to be significantly higher than the control group (p>0.05). There was no statistically significant difference between the experimental and control groups in the total CASI AD levels for the post-operative recovery room and for returning to the service room after the operation (p>0.05). VAS levels for patients in the experimental group in the post-operative recovery room was significantly higher than the control group (p>0.05). There was no statistically significant difference between the groups in terms of VAS findings in returning to service room after the operation and in 30 minutes before the discharge (p>0.05). As a result of the research; applied children music therapy in the experimental group anxiety, fear, and pain of the scales, their scores average, is lower than the control group children in this situation an increase in the satisfaction of children and parents was observed. In line with this, music therapy preoperative anxiety, fear, and can be used as an effective method of decreasing postoperative pain clinics is suggested.

Keywords: anxiety, children, fear, music therapy, pain

Procedia PDF Downloads 224

Authors: Aman Johri, Sidhant Sood, Pooja Suresh

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This paper suggests a new and more efficient method of atomization of fuel in a combustor nozzle of a high bypass turbofan engine, using ultrasonic vibrations. Since atomization of fuel just before the fuel spray is injected into the combustion chamber is an important and crucial aspect related to functioning of a propulsion system, the technology suggested by this paper and the experimental analysis on the system components eventually proves to assist in complete and rapid combustion of the fuel in the combustor module of the engine. Current propulsion systems use carburetors, atomization nozzles and apertures in air intake pipes for atomization. The idea of this paper is to deploy new age hybrid technology, namely the Ultrasound Field Effect (UFE) to effectively atomize fuel before it enters the combustion chamber, as a viable and effective method to increase efficiency and improve upon existing designs. The Ultrasound Field Effect is applied axially, on diametrically opposite ends of an atomizer tube that gloves onto the combustor nozzle, where the fuel enters and exits under a pre-defined pressure. The Ultrasound energy vibrates the fuel particles to a breakup frequency. At reaching this frequency, the fuel particles start disintegrating into smaller diameter particles perpendicular to the axis of application of the field from the parent boundary layer of fuel flow over the baseplate. These broken up fuel droplets then undergo swirling effect as per the original nozzle design, with a higher breakup ratio than before. A significant reduction of the size of fuel particles eventually results in an increment in the propulsive efficiency of the engine. Moreover, the Ultrasound atomizer operates within a control frequency such that effects of overheating and induced vibrations are least felt on the overall performance of the engine. The design of an electrical manifold for the multiple-nozzle system over a typical can-annular combustor is developed along with this study, such that the product can be installed and removed easily for maintenance and repairing, can allow for easy access for inspections and transmits least amount of vibrational energy to the surface of the combustor. Since near-field ultrasound is used, the vibrations are easily controlled, thereby successfully reducing vibrations on the outer shell of the combustor. Experimental analysis is carried out on the effect of ultrasonic vibrations on flowing jet turbine fuel using an ultrasound generator probe and results of an effective decrease in droplet size across a constant diameter, away from the boundary layer of flow is noted using visual aid by observing under ultraviolet light. The choice of material for the Ultrasound inducer tube and crystal along with the operating range of temperatures, pressures, and frequencies of the Ultrasound field effect are also studied in this paper, while taking into account the losses incurred due to constant vibrations and thermal loads on the tube surface.

Keywords: atomization, ultrasound field effect, titanium mesh, breakup frequency, parent boundary layer, baseplate, propulsive efficiency, jet turbine fuel, induced vibrations

Procedia PDF Downloads 240

Authors: Antonia Egli, Theo Lynn, Pierangelo Rosati, Gary Sinclair

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The World Health Organization (WHO) defines vaccine hesitancy as the postponement or complete denial of vaccines and estimates a direct linkage to approximately 1.5 million avoidable deaths annually. This figure is not immune to public health developments, as has become evident since the global spread of COVID-19 from Wuhan, China in early 2020. Since then, the proliferation of influential, but oftentimes inaccurate, outdated, incomplete, or false vaccine-related information on social media has impacted hesitancy levels to a degree described by the WHO as an infodemic. The COVID-19 pandemic and related vaccine hesitancy levels have in 2022 resulted in the largest drop in childhood vaccinations of the 21st century, while the prevalence of online stigma towards vaccine hesitant consumers continues to grow. Simultaneously, a second disease has risen to global importance: Monkeypox is an infection originating from west and central Africa and, due to racially motivated online hate, was in August 2022 set to be renamed by the WHO. To better understand public reactions towards two viral infections that became global threats to public health no two years apart, this research examines user replies to threads published by the WHO on Twitter. Replies to two Tweets from the @WHO account declaring COVID-19 and Monkeypox as ‘public health emergencies of international concern’ on January 30, 2020, and July 23, 2022, are gathered using the Twitter application programming interface and user mention timeline endpoint. Research methodology is unique in its analysis of stigmatizing, racist, and hateful content shared on social media within the vaccine discourse over the course of two disease outbreaks. Three distinct analyses are conducted to provide insight into (i) the most prevalent topics and sub-topics among user reactions, (ii) changes in sentiment towards the spread of the two diseases, and (iii) the presence of stigma, racism, and online hate. Findings indicate an increase in hesitancy to accept further vaccines and social distancing measures, the presence of stigmatizing content aimed primarily at anti-vaccine cohorts and racially motivated abusive messages, and a prevalent fatigue towards disease-related news overall. This research provides value to non-profit organizations or government agencies associated with vaccines and vaccination programs in emphasizing the need for public health communication fitted to consumers' vaccine sentiments, levels of health information literacy, and degrees of trust towards public health institutions. Considering the importance of addressing fears among the vaccine hesitant, findings also illustrate the risk of alienation through stigmatization, lead future research in probing the relatively underexamined field of online, vaccine-related stigma, and discuss the potential effects of stigma towards vaccine hesitant Twitter users in their decisions to vaccinate.

Keywords: social marketing, social media, public health communication, vaccines

Procedia PDF Downloads 100

Authors: Guillaume Soubeyran, Fabrice Micoud, Benoit Morin, Jean-Philippe Poirot-Crouvezier, Magali Reytier

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Proton Exchange Membrane Fuel Cell (PEMFC) technology is considered as a solution for the reduction of CO2 emissions. However, this technology still meets several challenges for high-scale industrialization. In this context, the increase of durability remains a critical aspect for competitiveness of this technology. Fortunately, performance degradations in nominal operating conditions is partially reversible, meaning that if specific conditions are applied, a partial recovery of fuel cell performance can be achieved, while irreversible degradations can only be mitigated. Thus, it is worth studying the optimal conditions to rejuvenate these reversible degradations and assessing the long-term impact of such procedures on the performance of the cell. Reversible degradations consist mainly of anode Pt active sites poisoning by carbon monoxide at the anode, heterogeneities in water management during use, and oxidation/deactivation of Pt active sites at the cathode. The latter is identified as a major source of reversible performance loss caused by the presence oxygen, high temperature and high cathode potential that favor platinum oxidation, especially in high efficiency operating points. Hence, we studied here a recovery procedure aiming at reducing the platinum oxides by decreasing cathode potential during operation. Indeed, the application of short air starvation phase leads to a drop of cathode potential. Cell performances are temporarily increased afterwards. Nevertheless, local temperature and current heterogeneities within the cells are favored and shall be minimized. The consumption of fuel during the recovery phase shall also be considered to evaluate the global efficiency. Consequently, the purpose of this work is to find an optimal compromise between the recovery of reversible degradations by air starvation, the increase of global cell efficiency and the mitigation of irreversible degradations effects. Different operating parameters have first been studied such as cell voltage, temperature and humidity in single cell set-up. Considering the global PEMFC system efficiency, tests showed that reducing duration of recovery phase and reducing cell voltage was the key to ensure an efficient recovery. Recovery phase frequency was a major factor as well. A specific method was established to find the optimal frequency depending on the duration and voltage of the recovery phase. Then, long-term degradations have also been studied by applying FC-DLC cycles based on NEDC cycles on a 4-cell short stack by alternating test sequences with and without recovery phases. Depending on recovery phase timing, cell efficiency during the cycle was increased up to 2% thanks to a mean voltage increase of 10 mV during test sequences with recovery phases. However, cyclic voltammetry tests results suggest that the implementation of recovery phases causes an acceleration of the decrease of platinum active areas that could be due to the high potential variations applied to the cathode electrode during operation.

Keywords: durability, PEMFC, recovery procedure, reversible degradation

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Authors: Seungsik Yu, Minho Kang

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As the threat of terrorism to nuclear facilities is increasing globally after the attacks of September 11, we are striving to recognize the physical protection system and strengthen the emergency response system. Since 2015, Korea has implemented physical protection security exercise for nuclear facilities. The exercise should be carried out with full cooperation between the operator and response forces. Performance testing of the physical protection system should include appropriate exercises, for example, force-on-force exercises, to determine if the response forces can provide an effective and timely response to prevent sabotage. Significant deficiencies and actions taken should be reported as stipulated by the competent authority. The IAEA(International Atomic Energy Agency) is also preparing force-on-force exercise program documents to support exercise of member states. Currently, ROK(Republic of Korea) is implementing exercise on the force-on-force exercise evaluation system which is developed by itself for the nuclear power plant, and it is necessary to establish the exercise procedure considering the use of the force-on-force exercise evaluation system. The purpose of this study is to establish the work procedures of the three major organizations related to the force-on-force exercise of nuclear power plants in ROK, which conduct exercise using force-on-force exercise evaluation system. The three major organizations are composed of licensee, KINAC (Korea Institute of Nuclear Nonproliferation and Control), and the NSSC(Nuclear Safety and Security Commission). Major activities are as follows. First, the licensee establishes and conducts an exercise plan, and when recommendations are derived from the result of the exercise, it prepares and carries out a force-on-force result report including a plan for implementation of the recommendations. Other detailed tasks include consultation with surrounding units for adversary, interviews with exercise participants, support for document evaluation, and self-training to improve the familiarity of the MILES (Multiple Integrated Laser Engagement System). Second, KINAC establishes a force-on-force exercise plan review report and reviews the force-on-force exercise plan report established by licensee. KINAC evaluate force-on-force exercise using exercise evaluation system and prepare training evaluation report. Other detailed tasks include MILES training, adversary consultation, management of exercise evaluation systems, and analysis of exercise evaluation results. Finally, the NSSC decides whether or not to approve the force-on-force exercise and makes a correction request to the nuclear facility based on the exercise results. The most important part of ROK's force-on-force exercise system is the analysis through the exercise evaluation system implemented by KINAC after the exercise. The analytical method proceeds in the order of collecting data from the exercise evaluation system and analyzing the collected data. The exercise application process of the exercise evaluation system introduced in ROK in 2016 will be concretely set up, and a system will be established to provide objective and consistent conclusions between exercise sessions. Based on the conclusions drawn up, the ultimate goal is to complement the physical protection system of licensee so that the system makes licensee respond effectively and timely against sabotage or unauthorized removal of nuclear materials.

Keywords: Force-on-Force exercise, nuclear power plant, physical protection, sabotage, unauthorized removal

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Authors: Binbin Chen, Dennis Y. C. Leung

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Aluminium (Al) -air cell holds a high volumetric capacity density of 8.05 Ah cm-3, benefit from the trivalence of Al ions. Additional benefits of Al-air cell are low price and environmental friendliness. Furthermore, the Al energy conversion process is characterized of 100% recyclability in theory. Along with a large base of raw material reserve, Al attracts considerable attentions as a promising material to be integrated within the global energy system. However, despite the early successful applications in military services, several problems exist that prevent the Al-air cells from widely civilian use. The most serious issue is the parasitic corrosion of Al when contacts with electrolyte. To overcome this problem, super-pure Al alloyed with various traces of metal elements are used to increase the corrosion resistance. Nevertheless, high-purity Al alloys are costly and require high energy consumption during production process. An alternative approach is to add inexpensive inhibitors directly into the electrolyte. However, such additives would increase the internal ohmic resistance and hamper the cell performance. So far these methods have not provided satisfactory solutions for the problem within Al-air cells. For the operation of alkaline Al-air cell, there are still other minor problems. One of them is the formation of aluminium hydroxide in the electrolyte. This process decreases ionic conductivity of electrolyte. Another one is the carbonation process within the gas diffusion layer of cathode, blocking the porosity of gas diffusion. Both these would hinder the performance of cells. The present work optimizes the above problems by building an Al-air cell operation system, consisting of four components. A top electrolyte tank containing fresh electrolyte is located at a high level, so that it can drive the electrolyte flow by gravity force. A mechanical rechargeable Al-air cell is fabricated with low-cost materials including low grade Al, carbon paper, and PMMA plates. An electrolyte waste tank with elaborate channel is designed to separate the hydrogen generated from the corrosion, which would be collected by gas collection device. In the first section of the research work, we investigated the performance of the mechanical rechargeable Al-air cell with a constant flow rate of electrolyte, to ensure the repeatability experiments. Then the whole system was assembled together and the feasibility of operating was demonstrated. During experiment, pure hydrogen is collected by collection device, which holds potential for various applications. By collecting this by-product, high utilization efficiency of aluminum is achieved. Considering both electricity and hydrogen generated, an overall utilization efficiency of around 90 % or even higher under different working voltages are achieved. Fluidic electrolyte could remove aluminum hydroxide precipitate and solve the electrolyte deterioration problem. This operation system provides a low-cost strategy for harvesting energy from the abundant secondary Al. The system could also be applied into other metal-air cells and is suitable for emergency power supply, power plant and other applications. The low cost feature implies great potential for commercialization. Further optimization, such as scaling up and optimization of fabrication, will help to refine the technology into practical market offerings.

Keywords: aluminium-air cell, high efficiency, hydrogen, mechanical recharge

Procedia PDF Downloads 284

Authors: Lucas Nascimento, Ana Rita, Margarida Soares, André Ribeiro, Zlatina Genisheva, Hugo Silva, Joana Carvalho

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The footwear industry is an essential fashion industry, focusing on producing various types of footwear, such as shoes, boots, sandals, sneakers, and slippers. Global footwear consumption has doubled every 20 years since the 1950s. It is estimated that in 1950, each person consumed one new pair of shoes yearly; by 2005, over 20 billion pairs of shoes were consumed. To meet global footwear demand, production reached $24.2 billion, equivalent to about $74 per person in the United States. This means three new pairs of shoes per person worldwide. The issue of footwear waste is related to the fact that shoe production can generate a large amount of waste, much of which is difficult to recycle or reuse. This waste includes scraps of leather, fabric, rubber, plastics, toxic chemicals, and other materials. The search for alternative solutions for waste treatment and valorization is increasingly relevant in the current context, mainly when focused on utilizing waste as a source of substitute materials. From the perspective of the new circular economy paradigm, this approach is of utmost importance as it aims to preserve natural resources and minimize the environmental impact associated with sending waste to landfills. In this sense, the incorporation of waste into industrial sectors that allow for the recovery of large volumes, such as road construction, becomes an urgent and necessary solution from an environmental standpoint. This study explores the use of plastic waste from the footwear industry as a substitute for virgin polymers in bitumen modification, a solution that presents a more sustainable future. Replacing conventional polymers with plastic waste in asphalt composition reduces the amount of waste sent to landfills and offers an opportunity to extend the lifespan of road infrastructures. By incorporating waste into construction materials, reducing the consumption of natural resources and the emission of pollutants is possible, promoting a more circular and efficient economy. In the initial phase of this study, waste materials from end-of-life footwear were selected, and plastic waste with the highest potential for application was separated. Based on a literature review, EVA (ethylene vinyl acetate) and PU (polyurethane) were identified as the polymers suitable for modifying 50/70 classification bitumen. Each polymer was analysed at concentrations of 3% and 5%. The production process involved the polymer's fragmentation to a size of 4 millimetres after heating the materials to 180 ºC and mixing for 10 minutes at low speed. After was mixed for 30 minutes in a high-speed mixer. The tests included penetration, softening point, viscosity, and rheological assessments. With the results obtained from the tests, the mixtures with EVA demonstrated better results than those with PU, as EVA had more resistance to temperature, a better viscosity curve and a greater elastic recovery in rheology.

Keywords: footwear waste, hot asphalt pavement, modified bitumen, polymers

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Authors: Drishti Sharma, Mona Duggal

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Background: WhatsApp can serve as a cost-effective, scalable, convenient, and popular medium for public health management related communication in the developing world where the existing system of communication is top-down and slow. The product supports sending and receiving a variety of media: text, photos, videos, documents, and location, as well as voice/video calls. With growing number of users of smartphones and improving access and penetration of internet, the scope of information technology remains immense in resolving the hurdles faced by traditional public health system. Poor infrastructure, gap in digital literacy, faulty documentation, strict organizational hierarchy and slow movement of information across desks and offices- all these, make WhatsApp an efficient prospect to complement the existing system for communication, feedback and leadership for public health system in India. Objective: This study investigates the benefits, challenges and limitations associated with WhatsApp usage as a public health management tool. Methods: The study was conducted within the Chandigarh Union Territory. We used a qualitative approach and conducted individual semi-structured interviews and group interviews (n = 10). Participants included medical officers (n 20), Program managers (n = 4), academicians (n=2) and administrators (n=2). Thematic and content qualitative analyses were conducted. Message log of the WhatsApp group of one of the health program was assessed. Results: Medical Officers said that WhatsApp helped them remain in touch with the program officer. They could easily give feedback and highlight those challenges which needed immediate intervention from the program managers, hence they felt supported. Also, the application helped them share pictures of their activities (meetings and field activities) with the group which they thought inspired others and gave themselves immense satisfaction. Also, it helped build stronger relationships and better coordination among themselves, the same being important in team events. For program managers, it had become a portal for coordinating large scale campaigns. Its reach and the fact that the feedback is real-time make WhatsApp ideal for district level events. Though the easy informal connectivity made them answerable to their staff but it also provided them with flexibility in operations. It turned out to be an important portal for sharing outcome and goals related feedback (both positive and negative) to the team. To be sure, using WhatsApp for the purpose of public health program presents considerable challenges, including technological barriers, organizational challenges, gender issues, confidentiality concerns and unplanned aftereffects. Nevertheless, its advantages in a low-cost setting make it an efficient alternative. Conclusion: WhatsApp has become an integral part of our lives. Use of this app for public health program management within closed groups looks promising and useful. At the same time, addressing the challenges involved would make its usage safer.

Keywords: communication, mobile technology, public health management, WhatsApp

Procedia PDF Downloads 178

Authors: A. Odoom, A. Salama, H. Ibrahim

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Hydrogen is a clean source of energy for power production and transportation. The main source of hydrogen in this research is biodiesel. Glycerol also called glycerine is a by-product of biodiesel production by transesterification of vegetable oils and methanol. This is a reliable and environmentally-friendly source of hydrogen production than fossil fuels. A typical composition of crude glycerol comprises of glycerol, water, organic and inorganic salts, soap, methanol and small amounts of glycerides. Crude glycerol has limited industrial application due to its low purity thus, the usage of crude glycerol can significantly enhance the sustainability and production of biodiesel. Reforming techniques is an approach for hydrogen production mainly Steam Reforming (SR), Autothermal Reforming (ATR) and Partial Oxidation Reforming (POR). SR produces high hydrogen conversions and yield but is highly endothermic whereas POR is exothermic. On the downside, PO yields lower hydrogen as well as large amount of side reactions. ATR which is a fusion of partial oxidation reforming and steam reforming is thermally neutral because net reactor heat duty is zero. It has relatively high hydrogen yield, selectivity as well as limits coke formation. The complex chemical processes that take place during the production phases makes it relatively difficult to construct a reliable and robust numerical model. Numerical model is a tool to mimic reality and provide insight into the influence of the parameters. In this work, we introduce a finite volume numerical study for an 'in-house' lab-scale experiment of ATR. Previous numerical studies on this process have considered either using Comsol or nodal finite difference analysis. Since Comsol is a commercial package which is not readily available everywhere and lab-scale experiment can be considered well mixed in the radial direction. One spatial dimension suffices to capture the essential feature of ATR, in this work, we consider developing our own numerical approach using MATLAB. A continuum fixed bed reactor is modelled using MATLAB with both pseudo homogeneous and heterogeneous models. The drawback of nodal finite difference formulation is that it is not locally conservative which means that materials and momenta can be generated inside the domain as an artifact of the discretization. Control volume, on the other hand, is locally conservative and suites very well problems where materials are generated and consumed inside the domain. In this work, species mass balance, Darcy’s equation and energy equations are solved using operator splitting technique. Therefore, diffusion-like terms are discretized implicitly while advection-like terms are discretized explicitly. An upwind scheme is adapted for the advection term to ensure accuracy and positivity. Comparisons with the experimental data show very good agreements which build confidence in our modeling approach. The models obtained were validated and optimized for better results.

Keywords: autothermal reforming, crude glycerol, hydrogen, numerical model

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Authors: Adrian Priceputu, Elena Mihaela Stan

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Our research addresses a critical challenge in renewable energy: improving efficiency and reducing the costs associated with the installation of ground-mounted photovoltaic (PV) panels. The most commonly used foundation solution is metal piles - with various sections adapted to soil conditions and the structural model of the panels. However, direct foundation systems are also sometimes used, especially in brownfield sites. Although metal micropiles are generally the first design option, understanding and predicting their bearing capacity, particularly under varied soil conditions, remains an open research topic. CPT Method and Current Challenges: Metal piles are favored for PV panel foundations due to their adaptability, but existing design methods rely heavily on costly and time-consuming in situ tests. The Cone Penetration Test (CPT) offers a more efficient alternative by providing valuable data on soil strength, stratification, and other key characteristics with reduced resources. During the test, a cone-shaped probe is pushed into the ground at a constant rate. Sensors within the probe measure the resistance of the soil to penetration, divided into cone penetration resistance and shaft friction resistance. Despite some existing CPT-based design approaches for metal piles, these methods are often cumbersome and difficult to apply. They vary significantly due to soil type and foundation method, and traditional approaches like the LCPC method involve complex calculations and extensive empirical data. The method was developed by testing 197 piles on a wide range of ground conditions, but the tested piles were very different from the ones used for PV pile foundations, making the method less accurate and practical for steel micropiles. Project Objectives and Methodology: Our research aims to develop a calculation method for metal micropile foundations using CPT data, simplifying the complex relationships involved. The goal is to estimate the pullout bearing capacity of piles without additional laboratory tests, streamlining the design process. To achieve this, a case study was selected which will serve for the development of an 80ha solar power station. Four testing locations were chosen spread throughout the site. At each location, two types of steel profiles (H160 and C100) were embedded into the ground at various depths (1.5m and 2.0m). The piles were tested for pullout capacity under natural and inundated soil conditions. CPT tests conducted nearby served as calibration points. The results served for the development of a preliminary equation for estimating pullout capacity. Future Work: The next phase involves validating and refining the proposed equation on additional sites by comparing CPT-based forecasts with in situ pullout tests. This validation will enhance the accuracy and reliability of the method, potentially transforming the foundation design process for PV panels.

Keywords: cone penetration test, foundation optimization, solar power stations, steel pile foundations

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Authors: Grant Bifolchi

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As global environmental problems continue to have highly adverse effects, finding long-term, sustainable solutions to combat ecological distress are of growing paramount concern. Ghost Gear—also known as abandoned, lost or otherwise discarded fishing gear (ALDFG) and derelict fishing gear (DFG)—represents one of the greatest threats to the world’s oceans, posing a significant hazard to human health, livelihoods, and global food security. In fact, according to the UN Food and Agriculture Organization (FAO), abandoned, lost and discarded fishing gear represents approximately 10% of marine debris by volume. Around the world, many governments, governmental and non-profit organizations are doing their best to manage the reporting and retrieval of nets, lines, ropes, traps, floats and more from their respective bodies of water. However, these organizations’ ability to effectively manage files and documents about the environmental problem further complicates matters. In Ghost Gear monitoring and management, organizations face additional complexities. Whether it’s data ingest, industry regulations and standards, garnering actionable insights into the location, security, and management of data, or the application of enforcement due to disparate data—all of these factors are placing massive strains on organizations struggling to save the planet from the dangers of Ghost Gear. In this 90-minute educational session, globally recognized Ghost Gear technology expert Grant Bifolchi CET, BBA, Bcom, will provide real-world insight into how governments currently manage Ghost Gear and the technology that can accelerate success in combatting ALDFG and DFG. In this session, attendees will learn how to: • Identify specific technologies to solve the ingest and management of Ghost Gear data categories, including type, geo-location, size, ownership, regional assignment, collection and disposal. • Provide enhanced access to authorities, fisheries, independent fishing vessels, individuals, etc., while securely controlling confidential and privileged data to globally recognized standards. • Create and maintain processing accuracy to effectively track ALDFG/DFG reporting progress—including acknowledging receipt of the report and sharing it with all pertinent stakeholders to ensure approvals are secured. • Enable and utilize Business Intelligence (BI) and Analytics to store and analyze data to optimize organizational performance, maintain anytime-visibility of report status, user accountability, scheduling, management, and foster governmental transparency. • Maintain Compliance Reporting through highly defined, detailed and automated reports—enabling all stakeholders to share critical insights with internal colleagues, regulatory agencies, and national and international partners.

Keywords: ghost gear, ALDFG, DFG, abandoned, lost or otherwise discarded fishing gear, data, technology

Procedia PDF Downloads 97

Authors: Robert Pocklington

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Most current language courses expect students to be ‘vocational’, sacrificing their free time in order to learn. However, pupils with a full-time job, or bringing up children, hardly have a spare moment. Others just need the language as a tool or a qualification, as if it were book-keeping or a driving license. Then there are children in unstructured families whose stressful life makes private study almost impossible. And the countless parents whose evenings and weekends have become a nightmare, trying to get the children to do their homework. There are many arguments against homework being a necessity (rather than an optional extra for more ambitious or dedicated students), making a clear case for teaching methods which facilitate full learning of the key content within the classroom. A methodology which could be described as Programmed Mastery Learning has been used at Fluency Language Academy (Spain) since 1992, to teach English to over 4000 pupils yearly, with a staff of around 100 teachers, barely requiring homework. The course is structured according to the tenets of Programmed Learning: small manageable teaching steps, immediate feedback, and constant successful activity. For the Mastery component (not stopping until everyone has learned), the memorisation and practice are entrusted to flashcard-based drilling in the classroom, leading all students to progress together and develop a permanently growing knowledge base. Vocabulary and expressions are memorised using flashcards as stimuli, obliging the brain to constantly recover words from the long-term memory and converting them into reflex knowledge, before they are deployed in sentence building. The use of grammar rules is practised with ‘cue’ flashcards: the brain refers consciously to the grammar rule each time it produces a phrase until it comes easily. This automation of lexicon and correct grammar use greatly facilitates all other language and conversational activities. The full B2 course consists of 48 units each of which takes a class an average of 17,5 hours to complete, allowing the vast majority of students to reach B2 level in 840 class hours, which is corroborated by an 85% pass-rate in the Cambridge University B2 exam (First Certificate). In the past, studying for qualifications was just one of many different options open to young people. Nowadays, youngsters need to stay at school and obtain qualifications in order to get any kind of job. There are many students in our classes who have little intrinsic interest in what they are studying; they just need the certificate. In these circumstances and with increasing government pressure to minimise failure, teachers can no longer think ‘If they don’t study, and fail, its their problem’. It is now becoming the teacher’s problem. Teachers are ever more in need of methods which make their pupils successful learners; this means assuring learning in the classroom. Furthermore, homework is arguably the main divider between successful middle-class schoolchildren and failing working-class children who drop out: if everything important is learned at school, the latter will have a much better chance, favouring inclusiveness in the language classroom.

Keywords: flashcard drilling, fluency method, mastery learning, programmed learning, teaching English as a foreign language

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Authors: Olugbenga S. Alebiosu, Olusola H. Adekanmbi, Oluwatoyin T. Ogundipe

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Pollen and spores have been identified as major airborne bio-particles inducing respiratory disorders such as asthma, allergic rhinitis and atopic dermatitis among hypersensitive individuals. An aeropalynological study was conducted within a one year sampling period with a view to investigating the monthly depositional rate of atmospheric pollen and spores; influence of the immediate vegetation on airborne pollen distribution; allergenic potentials of dominant atmospheric pollen types at selected study locations in Bauchi and Taraba states, Northwestern Nigeria. A tauber-like pollen trap was employed in aerosampling with the sampler positioned at a height of 5 feet above the ground, followed by a monthly collection of the recipient solution for the sampling period. The collected samples were subjected to acetolysis treatment, examined microscopically with the identification of pollen grains and spores using reference materials and published photomicrographs. Plants within the surrounding vegetation were enumerated. Crude protein contents extracted from pollen types found to be commonly dominant at both study locations; Senna siamea, Terminalia cattapa, Panicum maximum and Zea mays were used to sensitize Musmusculus. Histopathological studies of bronchi and lung sections from certain dead M.musculus in the test groups was conducted. Blood samples were collected from the pre-orbital vein of M.musculus and processed for serological and haematological (differential and total white blood cell counts) studies. ELISA was used in determining the levels of serological parameters: IgE and cytokines (TNF-, IL-5, and IL-13). Statistical significance was observed in the correlation between the levels of serological and haematological parameters elicited by each test group, differences between the levels of serological and haematological parameters elicited by each test group and those of the control, as well as at varying sensitization periods. The results from this study revealed dominant airborne pollen types across the study locations; Syzygiumguineense, Tridaxprocumbens, Elaeisguineensis, Mimosa sp., Borreria sp., Terminalia sp., Senna sp. and Poaceae. Nephrolepis sp., Pteris sp. and a trilete fern also produced spores. This study also revealed that some of the airborne pollen types were produced by local plants at the study locations. Bronchi sections of M.musculus after first and second sensitizations, as well as lung section after first sensitization with Senna siamea, showed areas of necrosis. Statistical significance was recorded in the correlation between the levels of some serological and haematological parameters produced by each test group and those of the control, as well as at certain sensitization periods. The study revealed some candidate pollen allergens at the study locations allergy sufferers and also established a complexity of interaction between immune cells, IgE and cytokines at varied periods of mice sensitization and forming a paradigm of human immune response to different pollen allergens. However, it is expedient that further studies should be conducted on these candidate pollen allergens for their allergenicity potential in humans within their immediate environment.

Keywords: airborne, hypersensitive, mus musculus, pollen allergens, respiratory, tauber-like

Procedia PDF Downloads 135

Authors: Ganesh V., Asit Kumar Khanra

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An in-situ powder metallurgy technique was employed to create Ni-Al3Ni/Al3Ni2 core-shell-shaped aluminum-based intermetallic reinforced composites. The impact of Ni addition on the phase composition, microstructure, and mechanical characteristics of the Al-4Cu-xNi (x = 0, 2, 4, 6, 8, 10 wt.%) in relation to various sintering temperatures was investigated. Microstructure evolution was extensively examined using X-ray diffraction (XRD), scanning electron microscopy with energy-dispersive X-ray spectroscopy (SEM-EDX), and transmission electron microscopy (TEM) techniques. Initially, under sintering conditions, the formation of "Single Core-Shell" structures was observed, consisting of Ni as the core with Al3Ni2 intermetallic, whereas samples sintered at 620°C exhibited both "Single Core-Shell" and "Double Core-Shell" structures containing Al3Ni2 and Al3Ni intermetallics formed between the Al matrix and Ni reinforcements. The composite achieved a high compressive yield strength of 198.13 MPa and ultimate strength of 410.68 MPa, with 24% total elongation for the sample containing 10 wt.% Ni. Additionally, there was a substantial increase in hardness, reaching 124.21 HV, which is 2.4 times higher than that of the base aluminum. Nanoindentation studies showed hardness values of 1.54, 4.65, 21.01, 13.16, 5.52, 6.27, and 8.39GPa corresponding to α-Al matrix, Ni, Al3Ni2, Ni and Al3Ni2 interface, Al3Ni, and their respective interfaces. Even at 200°C, it retained 54% of its room temperature strength (90.51 MPa). To investigate the deformation behavior of the composite material, experiments were conducted at deformation temperatures ranging from 300°C to 500°C, with strain rates varying from 0.0001s-1 to 0.1s-1. A sine-hyperbolic constitutive equation was developed to characterize the flow stress of the composite, which exhibited a significantly higher hot deformation activation energy of 231.44 kJ/mol compared to the self-diffusion of pure aluminum. The formation of Al2Cu intermetallics at grain boundaries and Al3Ni2/Al3Ni within the matrix hindered dislocation movement, leading to an increase in activation energy, which might have an adverse effect on high-temperature applications. Two models, the Strain-compensated Arrhenius model and the Artificial Neural Network (ANN) model, were developed to predict the composite's flow behavior. The ANN model outperformed the Strain-compensated Arrhenius model with a lower average absolute relative error of 2.266%, a smaller root means square error of 1.2488 MPa, and a higher correlation coefficient of 0.9997. Processing maps revealed that the optimal hot working conditions for the composite were in the temperature range of 420-500°C and strain rates between 0.0001s-1 and 0.001s-1. The changes in the composite microstructure were successfully correlated with the theory of processing maps, considering temperature and strain rate conditions. The uneven distribution in the shape and size of Core-shell/Al3Ni intermetallic compounds influenced the flow stress curves, leading to Dynamic Recrystallization (DRX), followed by partial Dynamic Recovery (DRV), and ultimately strain hardening. This composite material shows promise for applications in the automobile and aerospace industries.

Keywords: core-shell structure, hot deformation, intermetallic compounds, powder metallurgy

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