Search results for: minimal delamination
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 938

Search results for: minimal delamination

428 The Impact of Ozone on the Sensory Perception of Pumpkin Seeds and its Toxicity against Plodia interpunctella (Lepidoptera: Pyralidae)

Authors: Saba Goudarzi Dehrizifar, Aysan Afradi

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The utilization of ozone treatment as a potential technique for storage pest control has gained significant attention. This approach presents an alternative to traditional chemical methods. In the current study, the mortality rates of Plodia interpunctella as a primary pest found in stored products particularly nuts, were examined after being exposed to different O3 concentration (minimum, half, and maximum) in three replicates and within 24 hours. As the concentration of O3 increased, the mortality rates of P. interpunctella also experienced a dramatic growth. A 20-member panel (men and women in different ages), formed from the society community, was selected for sensory evaluation. The pumpkin seeds samples were coded and presented randomly in identical containers. The panelists were asked to evaluate their degree of liking or disliking on a seven-point hedonic scale using descriptive categories, ranging 1-7 (1: extremely dislike, 2: very dislike, 3: dislike, 4: no difference, 5: like, 6: very like, and 7: extremely like). The results obtained from experiments on the qualitative characteristics of the studied dates through the sensory test revealed that O3 concentration did not affect their color, crispness, firmness, and overall acceptance and the half concentration of ozone on pumpkin seed had the highest consumption interest. Moreover, minimal alterations were observed in the aroma of the pumpkin seeds, which could be resolved with a short period of air exposure. Therefore, it could be concluded that the atmospheric O3 gas provided a cost-effective and environmentally friendly way for controlling the insect pests in pumpkin seeds, besides preserving their sensory and quality properties.

Keywords: zone, control, pumpkin seeds, qualitative characteristics

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427 Administrative Determinants of Students' Sports Participation in Private and Public Secondary Schools in Kwara State, Nigeria

Authors: Danjuma Moudu Momoh

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Participation in sports is of immense benefit to the soundness of individual mental and social wellness, particularly among youngsters. The 1980’s and 1990’s compared to 2000’s witnessed great involvement of youngsters in school games arising from the high administrative supports attached to sports. Previous studies in an attempt to increase youngster’s participation in sports had focused more on other factors rather than on administrative factors. This study, therefore, investigated the importance of administrative factors (availability of facilities, availability of equipment, funding, scheduling of sports programme and administrative style of school principals) on students’ sports participation in private and public secondary schools in Kwara State, Nigeria. Descriptive survey research design using validated and structured questionnaire, was adopted. Stratified random sampling technique was used to pick the students both male and female. A total of two thousand five hundred and sixty participants were involved in the study. A reliable coefficient of r=0.82 was obtained for the instruments using Cronbach Alpha. Data were analyzed using multiple regressions to test the hypotheses at 00.5 significant levels. At the end of the study, it was discovered that the relative contributions of administrative factors among the students were: availability of facilities (β=0.314), availability of equipment (β=0.444), funding (β=0.301), scheduling of sports programme (β=0.447), made relative contributions to the dependent variable, administrative style of school principal (β=0.077) did not make significant but minimal contribution to the student’s sports participation.

Keywords: administrative determinants, secondary school students, physical activity, sports participation

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426 Climate Risk Perception and Trust – Presence of a Social Trap for Willingness to Act in Favour of Climate Mitigation and Support for Renewables: A Cross-sectional Study of Four European Countries

Authors: Lana Singleton

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Achieving a sufficient global solution to climate change seems elusive through disappointing climate agreements and lack of cooperation. However, is this reluctance of coordination deep rooted on a more individual, societal level within countries due to a fundamental lack of social and institutional trust? The risks of climate change are illustrious and widely accepted, yet responses on an individual level are also largely inadequate. This research looks to further investigate types of trust, risk perception of climate change, and their interaction to build a greater understanding of whether a social trap (Rothstein, 2005) – where an absence of trust can overwhelm an individuals’ risk perception and result in minimal action despite knowing the dangers of no action – exists and where it is more prevalent. Presence of the social trap will be analysed for willingness to act in favour of climate change mitigation as well as attitude (acceptance) of different types of renewable energy forms. Using probit models with cross-sectional survey data on four developed European countries (UK, France, Germany, and Norway), we find evidence of the social trap in the aggregated data model, which highlights the importance of social trust regarding willingness to act in favour of climate mitigation as there is a high probability of action regardless of risk perception of climate change when social trust is high. In contrast, the same is not true for renewables, as interactions were mainly insignificant, although there were interesting findings involving institutional trust, gender, and country specific results for particular renewables.

Keywords: climate risk, renewables, risk perception, social trap, trust, willingness to act

Procedia PDF Downloads 81
425 Environmental Users’ Perceptions on Tourism in the Grangettes Nature Reserve, Switzerland

Authors: Ralph Lugon, Randolf Ramseyer

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The beauty and quality of the natural heritage can be appreciated in different ways by different users, but the delicate balance of the environment in a nature reserve must be respected. The case of the territorial anchorage of the Grangettes natural reserve gives an interesting insight into the users' perception of the environmental constraints and standards of tourist activities. The nature reserve was once conceived as a sanctuary of natural heritage, a place where flora and fauna could flourish with minimal human interference. However, over time and with the transition to modernity, the values and meanings of the reserve have changed for visitors and the people living in the surrounding area. Today, The Grangettes nature reserve is a place of relaxation for urban dwellers with limited knowledge of nature and a lack of awareness of conservation issues. As a result, the reserve is now threatened by the negative impacts of human activities and mass tourism on its environment. Les Grangettes is a nature reserve that faces the challenge of preserving biodiversity while managing tourist flows. Ways must be found to accommodate new types of visitors from towns and cities who are looking for new activities, quality services and facilities, as well as aesthetic inspiration. To ensure the long-term conservation of the area, the flow of tourists must be carefully controlled. Through a dual qualitative-quantitative approach in 2021-22, this paper explores new visitor trends, changes in the reserve, and potential consequences for other stakeholders in the ecosystem. The purpose of this research is to assess users' perceptions of environmental constraints and standards on tourist activities in a nature reserve.

Keywords: outdoor recreation, nature-based tourism, over tourism, protected area, user's perceptions

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424 Effects of Paternity: A Comparative Study to Analyze the Organization's Support in the Psychological Development of Children in India and USA

Authors: Aayushi Dalal

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It is the mother who bears the child in her womb for 9 months. It is typically rooted in the Indian culture that it is solely the responsibility of women to take care of the children and as a result the gender roles are stereotyped. Instead of a 50-50 partnership in parenting the child, it is hackneyed that men take the responsibility of the bread earner while women nurture the children by staying at home. Thus, mothers are considered to be more psychologically connected to the children than fathers. But the current society is observing role dilution of parents which can create a gap in understanding from the organization’s perspective. This is the basis of the study. The emergence of women into the job market has forever changed how society views the traditional roles of fathers and mothers. Feminism and financial power has reformed the classic parenting model. This has given rise to a more open and flexible society consequently emphasizing the father's importance in the emotional well being of the child while also being capable caretakers and disciplinarians. This study focuses on analyzing the comparative differences of the father's role in the psychological development of the child in India and USA while taking into consideration the organization’s support towards them. A sample size of 150 fathers- 75 from India and 75 from USA was selected and a structured survey was carried out which had several open ended as well as closed ended questions probing to the issue. It was made sure that the environmental factors had as minimal effect as possible on the subjects. The findings of this research would materialize a framework for fathers to understand the magnitude of their role in their child's upbringing. This would not only ameliorate the "father-child" relationship but also make organization more sympathetic towards their employees.

Keywords: paternity, child development, psychology, gender role, organization policy

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423 The Use of Complementary and Alternative Medicine for Pain Relief in the Elderly: An Investigational Analysis of Seniors Residing in an Independent/Assisted Seniors’ Living Facility

Authors: Carol Cameletti

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The goal of this study was to perform a pilot survey to assess pain frequency and intensity in an elderly population and to assess treatment options for chronic pain that include complementary and alternative medicines (CAM). Ten participants were recruited from an independent and supportive living housing facility in Northern Ontario and asked to complete two questionnaires: 1) a self-assessment on pain, and 2) the use of CAM for pain. Results from our study show that 80% of the participants experienced pains other than the regular everyday pains such as minor headaches, sprains or toothaches. Although participants stated that on average the highest level of pain they experienced within the past 24 hours had a score of 6.5 (0=no pain, 10=worst pain imaginable) the level of pain they experienced moderately interfered with their daily activities. Unfortunately, participants stated that they were only able to attain minimal levels of pain relief using treatments or medications causing some of the participants to seek alternative therapies or self-help practices. The most commonly used CAMs were vitamins/minerals, herbs and supplements, and self-help practices such as meditation, prayer, visualization and relaxation techniques. Although some of the participants stated that they had received complementary treatments directly from their physician, four of the nine participants said that they had not disclosed CAM use to their physician thereby indicating a need to open the lines of communication between healthcare providers and patients with regards to CAM use. It is our hope that the data generated from this study will serve as the platform for a pain management clinic that is client-centered, consumer-driven and truly integrative and tailored in order to meet the unique needs of older adults in Great Sudbury, Ontario.

Keywords: alternative, complementary, elderly, medicine

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422 Isolation and Characterization of Bio-surfactant Producing Alcaligenes sp YLA1 and Its Diesel Degradation Potentials

Authors: Abdulrahman Abdulhamid Arabo, Raji Arabi Bamanga, Mujiburrahman Fadilu, Musa Abubakar, Fatima Abdullahi Shehu, Hafeez Muhammad Yakasai, Nasiru Abdullahi

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The aim of this study was to isolate and identify biosurfactant-producing and diesel alkanes degrading bacteria. For this reason, bacteria isolated from the diesel-contaminated site were screened for their potential to produce biosurfactants and degrade diesel alkanes. Primary selection of diesel degraders was carried out by using the conventional enrichment culture technique, where 12 bacterial strains were isolated based on their ability to grow on minimal media supplemented with diesel as the sole carbon source, which was followed by qualitative screening methods for potential biosurfactant production. Isolate B11 was the only candidate that showed positive signs for drop collapse, foaming, hemolytic test, oil displacement of more than 22 ± 0.05 mm, and emulsification (E24) of 14 ± 0.30%. The effect of various culture parameters (incubation time, diesel concentration, nitrogen source, pH and temperature) on the biodegradation of diesel was evaluated. The optimum incubation time was confirmed to be 120 days for isolate B11, and the optimum PH was confirmed as 8.0 for the isolate; similarly, the optimum temperature was confirmed as 35oC. In addition, diesel oil was used as the sole carbon source for the isolates. The favorable diesel concentration was 12.5 % (v/v) for the isolate. The isolate has shown degradative ability towards Tridecane (C13), dodecane, 2, 6, 10-trimethyl- (C15), Tetradecane (C14), 2,6,10-Trimethyltridecane (C16), Pentadecane (C15). It degraded between 0.27% - 9.65% of individual diesel oil alkanes. The strain has exhibited the potential of degrading diesel oil n-alkanes and was identified as Alcaligenes species strain B11 (MZ027604) using the 16S rRNA. Sequencing.

Keywords: diesel oil, biosurfactant, Alcaligenes sp, biodegradation

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421 A Finite Element/Finite Volume Method for Dam-Break Flows over Deformable Beds

Authors: Alia Alghosoun, Ashraf Osman, Mohammed Seaid

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A coupled two-layer finite volume/finite element method was proposed for solving dam-break flow problem over deformable beds. The governing equations consist of the well-balanced two-layer shallow water equations for the water flow and a linear elastic model for the bed deformations. Deformations in the topography can be caused by a brutal localized force or simply by a class of sliding displacements on the bathymetry. This deformation in the bed is a source of perturbations, on the water surface generating water waves which propagate with different amplitudes and frequencies. Coupling conditions at the interface are also investigated in the current study and two mesh procedure is proposed for the transfer of information through the interface. In the present work a new procedure is implemented at the soil-water interface using the finite element and two-layer finite volume meshes with a conservative distribution of the forces at their intersections. The finite element method employs quadratic elements in an unstructured triangular mesh and the finite volume method uses the Rusanove to reconstruct the numerical fluxes. The numerical coupled method is highly efficient, accurate, well balanced, and it can handle complex geometries as well as rapidly varying flows. Numerical results are presented for several test examples of dam-break flows over deformable beds. Mesh convergence study is performed for both methods, the overall model provides new insight into the problems at minimal computational cost.

Keywords: dam-break flows, deformable beds, finite element method, finite volume method, hybrid techniques, linear elasticity, shallow water equations

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420 Performance Comparison of Microcontroller-Based Optimum Controller for Fruit Drying System

Authors: Umar Salisu

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This research presents the development of a hot air tomatoes drying system. To provide a more efficient and continuous temperature control, microcontroller-based optimal controller was developed. The system is based on a power control principle to achieve smooth power variations depending on a feedback temperature signal of the process. An LM35 temperature sensor and LM399 differential comparator were used to measure the temperature. The mathematical model of the system was developed and the optimal controller was designed and simulated and compared with the PID controller transient response. A controlled environment suitable for fruit drying is developed within a closed chamber and is a three step process. First, the infrared light is used internally to preheated the fruit to speedily remove the water content inside the fruit for fast drying. Second, hot air of a specified temperature is blown inside the chamber to maintain the humidity below a specified level and exhaust the humid air of the chamber. Third, the microcontroller disconnects the power to the chamber after the moisture content of the fruits is removed to minimal. Experiments were conducted with 1kg of fresh tomatoes at three different temperatures (40, 50 and 60 °C) at constant relative humidity of 30%RH. The results obtained indicate that the system is significantly reducing the drying time without affecting the quality of the fruits. In the context of temperature control, the results obtained showed that the response of the optimal controller has zero overshoot whereas the PID controller response overshoots to about 30% of the set-point. Another performance metric used is the rising time; the optimal controller rose without any delay while the PID controller delayed for more than 50s. It can be argued that the optimal controller performance is preferable than that of the PID controller since it does not overshoot and it starts in good time.

Keywords: drying, microcontroller, optimum controller, PID controller

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419 Improving Egg Production by Using Split-Phase Lighting Program

Authors: Hanan Al-Khalaifah, Afaf Al-Nasser

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The egg shell quality and oviposition in laying hens are influenced by a range of factors including strain of birds, age, nutrition, water quality, general stress, heat stress, disease, and lighting program inside houses. A layer experiment was conducted to investigate the effect of split-phase lighting program on egg production efficiency. Four different feeds and average phosphorus (av. P) levels were tested. Diet A was a ration with an av. P level of 0.471%; Diet B was a ration with an av. P level of 0.510%; Diet C contained an av. P level of 0.293%; and Diet D contained an av. P level of 0.327%. The split-phase lighting program tested was one that inserted a 7-hour dark period from 9 am to 4 pm to reduce the heat produced by the feeding increment and physical activity of the hens. Diet B produced significantly more eggs than Diet C, or Diet D. Diet A was not significantly different from any of the other diets. Diet B also had the best feed efficiency with the other three diets in the same order and significance as for egg production. Diet D produced eggshells significantly thicker than either Diet A, or Diet B. Diet C produced thicker eggshells than Diet B, whose shells were significantly thinner than the other three diets. There were no differences in egg size. From these data, it is apparent that the minimal av. P level for the Lohmann strain of layer in Kuwait is above 0.327%. There was no difference in egg production or eggshell thickness between the split-phase light treatment and the standard light program. There was no difference in oviposition frequency. The split-phase light used 3.66% less feed, however, which was significant. The standard light produced eggs that were significantly heavier (66.30g vs. 65.73g). These results indicate that considerable savings in feed costs could be attained by using split-phase lighting, especially when cooling is not very efficient.

Keywords: egg, laying, nutrition, oviposition

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418 Anyword: A Digital Marketing Tool to Increase Productivity in Newly Launching Businesses

Authors: Jana Atteah, Wid Jan, Yara AlHibshi, Rahaf AlRougi

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Anyword is an AI copywriting tool that helps marketers create effective campaigns for specific audiences. It offers a wide range of templates for various platforms, brand voice guidelines, and valuable analytics insights. Anyword is used by top global companies and has been recognized as one of the "Fastest Growing Products" in the 2023 software awards. A recent study examined the utilization and impact of AI-powered writing tools, specifically focusing on the adoption of AI in writing pursuits and the use of the Anyword platform. The results indicate that a majority of respondents (52.17%) had not previously used Anyword, but those who had were generally satisfied with the platform. Notable productivity improvements were observed among 13% of the participants, while an additional 34.8% reported a slight increase in productivity. A majority (47.8%) maintained a neutral stance, suggesting that their productivity remained unaffected. Only a minimal percentage (4.3%) claimed that their productivity did not improve with the usage of Anyword AI. In terms of the quality of written content generated, the participants responded positively. Approximately 91% of participants gave Anyword AI a score of 5 or higher, with roughly 17% giving it a perfect score. A small percentage (approximately 9%) gave a low score between 0-2. The mode result was a score of 7, indicating a generally positive perception of the quality of content generated using Anyword AI. These findings suggest that AI can contribute to increased productivity and positively influence the quality of written content. Further research and exploration of AI tools in writing pursuits are warranted to fully understand their potential and limitations.

Keywords: artificial intelligence, marketing platforms, productivity, user interface

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417 Overview Studies of High Strength Self-Consolidating Concrete

Authors: Raya Harkouss, Bilal Hamad

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Self-Consolidating Concrete (SCC) is considered as a relatively new technology created as an effective solution to problems associated with low quality consolidation. A SCC mix is defined as successful if it flows freely and cohesively without the intervention of mechanical compaction. The construction industry is showing high tendency to use SCC in many contemporary projects to benefit from the various advantages offered by this technology. At this point, a main question is raised regarding the effect of enhanced fluidity of SCC on the structural behavior of high strength self-consolidating reinforced concrete. A three phase research program was conducted at the American University of Beirut (AUB) to address this concern. The first two phases consisted of comparative studies conducted on concrete and mortar mixes prepared with second generation Sulphonated Naphtalene-based superplasticizer (SNF) or third generation Polycarboxylate Ethers-based superplasticizer (PCE). The third phase of the research program investigates and compares the structural performance of high strength reinforced concrete beam specimens prepared with two different generations of superplasticizers that formed the unique variable between the concrete mixes. The beams were designed to test and exhibit flexure, shear, or bond splitting failure. The outcomes of the experimental work revealed comparable resistance of beam specimens cast using self-compacting concrete and conventional vibrated concrete. The dissimilarities in the experimental values between the SCC and the control VC beams were minimal, leading to a conclusion, that the high consistency of SCC has little effect on the flexural, shear and bond strengths of concrete members.

Keywords: self-consolidating concrete (SCC), high-strength concrete, concrete admixtures, mechanical properties of hardened SCC, structural behavior of reinforced concrete beams

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416 A Randomized Control Trial Intervention to Combat Childhood Obesity in Negeri Sembilan: The Hebat! Program

Authors: Siti Sabariah Buhari, Ruzita Abdul Talib, Poh Bee Koon

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This study aims to develop and evaluate an intervention to improve eating habits, active lifestyle and weight status of overweight and obese children in Negeri Sembilan. The H.E.B.A.T! Program involved children, parents, and school and focused on behaviour and environment modification to achieve its goal. The intervention consists of H.E.B.A.T! Camp, parent’s workshop and school-based activities. A total of 21 children from intervention school and 22 children from control school who had BMI for age Z-score ≥ +1SD participated in the study. Mean age of subjects was 10.8 ± 0.3 years old. Four phases were included in the development of the intervention. Evaluation of intervention was conducted through process, impact and outcome evaluation. Process evaluation found that intervention program was implemented successfully with minimal modification and without having any technical problems. Impact and outcome evaluation was assessed based on dietary intake, average step counts, BMI for age z-score, body fat percentage and waist circumference at pre-intervention (T0), post-intervention 1 (T1) and post-intervention 2 (T2). There was significant reduction in energy (14.8%) and fat (21.9%) intakes (at p < 0.05) at post-intervention 1 (T1) in intervention group. By controlling for sex as covariate, there was significant intervention effect for average step counts, BMI for age z-score and waist circumference (p < 0.05). In conclusion, the intervention made an impact on positive behavioural intentions and improves weight status of the children. It is expected that the HEBAT! Program could be adopted and implemented by the government and private sector as well as policy-makers in formulating childhood obesity intervention.

Keywords: childhood obesity, diet, obesity intervention, physical activity

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415 Design, Synthesis and Evaluation of 4-(Phenylsulfonamido)Benzamide Derivatives as Selective Butyrylcholinesterase Inhibitors

Authors: Sushil Kumar Singh, Ashok Kumar, Ankit Ganeshpurkar, Ravi Singh, Devendra Kumar

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In spectrum of neurodegenerative diseases, Alzheimer’s disease (AD) is characterized by the presence of amyloid β plaques and neurofibrillary tangles in the brain. It results in cognitive and memory impairment due to loss of cholinergic neurons, which is considered to be one of the contributing factors. Donepezil, an acetylcholinesterase (AChE) inhibitor which also inhibits butyrylcholinesterase (BuChE) and improves the memory and brain’s cognitive functions, is the most successful and prescribed drug to treat the symptoms of AD. The present work is based on designing of the selective BuChE inhibitors using computational techniques. In this work, machine learning models were trained using classification algorithms followed by screening of diverse chemical library of compounds. The various molecular modelling and simulation techniques were used to obtain the virtual hits. The amide derivatives of 4-(phenylsulfonamido) benzoic acid were synthesized and characterized using 1H & 13C NMR, FTIR and mass spectrometry. The enzyme inhibition assays were performed on equine plasma BuChE and electric eel’s AChE by method developed by Ellman et al. Compounds 31, 34, 37, 42, 49, 52 and 54 were found to be active against equine BuChE. N-(2-chlorophenyl)-4-(phenylsulfonamido)benzamide and N-(2-bromophenyl)-4-(phenylsulfonamido)benzamide (compounds 34 and 37) displayed IC50 of 61.32 ± 7.21 and 42.64 ± 2.17 nM against equine plasma BuChE. Ortho-substituted derivatives were more active against BuChE. Further, the ortho-halogen and ortho-alkyl substituted derivatives were found to be most active among all with minimal AChE inhibition. The compounds were selective toward BuChE.

Keywords: Alzheimer disease, butyrylcholinesterase, machine learning, sulfonamides

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414 Fully Instrumented Small-Scale Fire Resistance Benches for Aeronautical Composites Assessment

Authors: Fabienne Samyn, Pauline Tranchard, Sophie Duquesne, Emilie Goncalves, Bruno Estebe, Serge Boubigot

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Stringent fire safety regulations are enforced in the aeronautical industry due to the consequences that potential fire event on an aircraft might imply. This is so much true that the fire issue is considered right from the design of the aircraft structure. Due to the incorporation of an increasing amount of polymer matrix composites in replacement of more conventional materials like metals, the nature of the fire risks is changing. The choice of materials used is consequently of prime importance as well as the evaluation of its resistance to fire. The fire testing is mostly done using the so-called certification tests according to standards such as the ISO2685:1998(E). The latter describes a protocol to evaluate the fire resistance of structures located in fire zone (ability to withstand fire for 5min). The test consists in exposing an at least 300x300mm² sample to an 1100°C propane flame with a calibrated heat flux of 116kW/m². This type of test is time-consuming, expensive and gives access to limited information in terms of fire behavior of the materials (pass or fail test). Consequently, it can barely be used for material development purposes. In this context, the laboratory UMET in collaboration with industrial partners has developed a horizontal and a vertical small-scale instrumented fire benches for the characterization of the fire behavior of composites. The benches using smaller samples (no more than 150x150mm²) enables to cut downs costs and hence to increase sampling throughput. However, the main added value of our benches is the instrumentation used to collect useful information to understand the behavior of the materials. Indeed, measurements of the sample backside temperature are performed using IR camera in both configurations. In addition, for the vertical set up, a complete characterization of the degradation process, can be achieved via mass loss measurements and quantification of the gasses released during the tests. These benches have been used to characterize and study the fire behavior of aeronautical carbon/epoxy composites. The horizontal set up has been used in particular to study the performances and durability of protective intumescent coating on 2mm thick 2D laminates. The efficiency of this approach has been validated, and the optimized coating thickness has been determined as well as the performances after aging. Reductions of the performances after aging were attributed to the migration of some of the coating additives. The vertical set up has enabled to investigate the degradation process of composites under fire. An isotropic and a unidirectional 4mm thick laminates have been characterized using the bench and post-fire analyses. The mass loss measurements and the gas phase analyses of both composites do not present significant differences unlike the temperature profiles in the thickness of the samples. The differences have been attributed to differences of thermal conductivity as well as delamination that is much more pronounced for the isotropic composite (observed on the IR-images). This has been confirmed by X-ray microtomography. The developed benches have proven to be valuable tools to develop fire safe composites.

Keywords: aeronautical carbon/epoxy composite, durability, intumescent coating, small-scale ‘ISO 2685 like’ fire resistance test, X-ray microtomography

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413 Design and Implementation of Control System in Underwater Glider of Ganeshblue

Authors: Imam Taufiqurrahman, Anugrah Adiwilaga, Egi Hidayat, Bambang Riyanto Trilaksono

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Autonomous Underwater Vehicle glider is one of the renewal of underwater vehicles. This vehicle is one of the autonomous underwater vehicles that are being developed in Indonesia. Glide ability is obtained by controlling the buoyancy and attitude of the vehicle using the movers within the vehicle. The glider motion mechanism is expected to provide energy resistance from autonomous underwater vehicles so as to increase the cruising range of rides while performing missions. The control system on the vehicle consists of three parts: controlling the attitude of the pitch, the buoyancy engine controller and the yaw controller. The buoyancy and pitch controls on the vehicle are sequentially referring to the finite state machine with pitch angle and depth of diving inputs to obtain a gliding cycle. While the yaw control is done through the rudder for the needs of the guide system. This research is focused on design and implementation of control system of Autonomous Underwater Vehicle glider based on PID anti-windup. The control system is implemented on an ARM TS-7250-V2 device along with a mathematical model of the vehicle in MATLAB using the hardware-in-the-loop simulation (HILS) method. The TS-7250-V2 is chosen because it complies industry standards, has high computing capability, minimal power consumption. The results show that the control system in HILS process can form glide cycle with depth and angle of operation as desired. In the implementation using half control and full control mode, from the experiment can be concluded in full control mode more precision when tracking the reference. While half control mode is considered more efficient in carrying out the mission.

Keywords: control system, PID, underwater glider, marine robotics

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412 Ferrites of the MeFe2O4 System (Me – Zn, Cu, Cd) and Their Two Faces

Authors: B. S. Boyanov, A. B. Peltekov, K. I. Ivanov

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The ferrites of Zn, Cd, Cu, and mixed ferrites with NiO, MnO, MgO, CoO, ZnO, BaO combine the properties of dielectrics, semiconductors, ferro-magnets, catalysts, etc. The ferrites are used in an impressive range of applications due to their remarkable properties. A specific disadvantage of ferrites is that they are undesirably obtained in a lot of processes connected with metal production. They are very stable and poorly soluble compounds. The obtained ZnFe2O4 in zinc production connecting about 15% of the total zinc remains practically insoluble in dilute solutions of sulfuric acid. This decreases the degree of recovery of zinc and necessitates to further process the zinc-containing cake. In this context, the ferrites; ZnFe2O4, CdFe2O4, and CuFe2O4 are synthesized in laboratory conditions using ceramic technology. Their homogeneity and structure are proven by X-Ray diffraction analysis and Mössbauer spectroscopy. The synthesized ferrites are subjected to strong acid and high temperature leaching with solutions of H2SO4, HCl, and HNO3 (7, 10 and 15 %). The results indicate that the highest degree of leaching of Zn, Cd, and Cu from the ferrites is achieved by use of HCl. The resulting values for the degree of leaching of metals using H2SO4 are lower, but still remain significantly higher for all of the experimental conditions compared to the values obtained using HNO3. Five zinc sulfide concentrates are characterized for iron content by chemical analysis, Web-based Information System, and iron phases by Mössbauer spectroscopy. The charging was optimized using the criterion of minimal amount of zinc ferrite produced when roasting the concentrates in a fluidized bed. The results obtained are interpreted in terms of the hydrometallurgical zinc production and maximum recovery of zinc, copper and cadmium from initial zinc sulfide concentrates after their roasting.

Keywords: hydrometallurgy, inorganic acids, solubility, zinc ferrite

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411 Exploiting Identity Grievances: Al-Shabaab Propaganda Targeting Individuals Abroad

Authors: Mustafa Mabruk

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Groups such as Al-Shabaab have managed to radicalize many individuals abroad, including the first American citizen to ever be radicalized. Yet the pathways of radicalization for these foreign individuals are understudied. Moreover, current measures to prevent foreign radicalization are ineffective, with privacy, screening and profiling implications that render current counter-radicalization efforts counterproductive. Such measures exhibit strictness, political bias, and harshness. As confirmed by recent studies, such counter-radicalization issues exacerbate existing grievances and channel fresh recruits to Al-Shabaab. Addressing these challenges is paramount, requiring alternative strategies to effectively reduce radicalization without triggering further harm. The development of counter-narratives emerges as a potential measure with minimal risk of exacerbating grievances, yet the development of such counter-narratives necessitates a thorough understanding of the radicalization pathways of foreign individuals that are understudied. This study investigates the success of Al-Shabaab in recruiting individuals abroad by analyzing their propaganda in conjunction with analyzing identity-focused theories of radicalization, including Framing Theory and Social Identity Theory. Qualitative content analysis is used to analyze various propaganda material, including tweets, speeches, and webpages. The analysis reveals that issues of identity are of major significance in the radicalization patterns identified and that grievances of Muslims worldwide are used to exploit identity-related grievances. Based on these findings, the paper argues that such evidence enhances our understanding of potential deradicalization pathways and present counter-narratives based on Islamic scripture.

Keywords: counter-narratives, foreign radicalization, identity grievances, propaganda analysis

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410 Comparison Between Conventional Ultrafiltration Combined with Modified Ultrafiltration and Conventional Ultrafiltration Only for Adult Open-heart Surgery: Perspective from Systemic Inflammation, Vascular Resistance, and Cardiac Index

Authors: Ratna Farida Soenarto, Anas Alatas, Made Ryan Kharmayani

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Background: Conventional ultrafiltration (CUF) system was shown to be helpful in reducing anti-inflammatory mediators for patients who underwent open heart surgery. Additionally, modified ultrafiltration (MUF) has been shown to reduce anti-inflammatory mediators further while reducing interstitial fluid volume at the same time. However, there has been minimal data concerning the efficacy of combining both ultrafiltration methods. This study aims to compare inflammation marker, vascular resistance, and cardiac index on CUF+MUF patients with CUF only patients undergoing open heart surgery. Method: This is a single blind randomized controlled trial on patients undergoing open heart surgery between June 2021 - October 2021 in CiptoMangunkusumo National Referral Hospital and Jakarta Heart Hospital. Patients wererandomized using block randomization into modified ultrafiltration following conventional ultrafiltration (CUF+MUF) and conventional ultrafiltration (CUF) only. Outcome assessed in this study were 24-hoursinterleukin-6 levels, systemic vascular resistance (SVR), pulmonary vascular resistance (PVR), and cardiac index. Results: A total of 38patients were included (19 CUF+MUF and 19 CUF subjects). There was no difference in postoperative IL-6 level between groups (p > 0.05).No difference in PVR was observed between groups.Higher difference in SVR was observed in CUF+MUF group (-646 vs. -261dyn/s/cm-5, p < 0.05). Higher cardiac index was observed on CUF+MUF group (0.93 vs. 0.48, p < 0.05). Conclusion: Patients undergoing open heart surgery with modified ultrafiltration following conventional ultrafiltration had similar systemic inflammatory response and better cardiac response than those having conventional ultrafiltration.

Keywords: open-heart, CUF, MUF, SVR, PVR, IL-6

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409 Modelling and Simulating CO2 Electro-Reduction to Formic Acid Using Microfluidic Electrolytic Cells: The Influence of Bi-Sn Catalyst and 1-Ethyl-3-Methyl Imidazolium Tetra-Fluoroborate Electrolyte on Cell Performance

Authors: Akan C. Offong, E. J. Anthony, Vasilije Manovic

Abstract:

A modified steady-state numerical model is developed for the electrochemical reduction of CO2 to formic acid. The numerical model achieves a CD (current density) (~60 mA/cm2), FE-faradaic efficiency (~98%) and conversion (~80%) for CO2 electro-reduction to formic acid in a microfluidic cell. The model integrates charge and species transport, mass conservation, and momentum with electrochemistry. Specifically, the influences of Bi-Sn based nanoparticle catalyst (on the cathode surface) at different mole fractions and 1-ethyl-3-methyl imidazolium tetra-fluoroborate ([EMIM][BF4]) electrolyte, on CD, FE and CO2 conversion to formic acid is studied. The reaction is carried out at a constant concentration of electrolyte (85% v/v., [EMIM][BF4]). Based on the mass transfer characteristics analysis (concentration contours), mole ratio 0.5:0.5 Bi-Sn catalyst displays the highest CO2 mole consumption in the cathode gas channel. After validating with experimental data (polarisation curves) from literature, extensive simulations reveal performance measure: CD, FE and CO2 conversion. Increasing the negative cathode potential increases the current densities for both formic acid and H2 formations. However, H2 formations are minimal as a result of insufficient hydrogen ions in the ionic liquid electrolyte. Moreover, the limited hydrogen ions have a negative effect on formic acid CD. As CO2 flow rate increases, CD, FE and CO2 conversion increases.

Keywords: carbon dioxide, electro-chemical reduction, ionic liquids, microfluidics, modelling

Procedia PDF Downloads 135
408 Development of a Telemedical Network Supporting an Automated Flow Cytometric Analysis for the Clinical Follow-up of Leukaemia

Authors: Claude Takenga, Rolf-Dietrich Berndt, Erling Si, Markus Diem, Guohui Qiao, Melanie Gau, Michael Brandstoetter, Martin Kampel, Michael Dworzak

Abstract:

In patients with acute lymphoblastic leukaemia (ALL), treatment response is increasingly evaluated with minimal residual disease (MRD) analyses. Flow Cytometry (FCM) is a fast and sensitive method to detect MRD. However, the interpretation of these multi-parametric data requires intensive operator training and experience. This paper presents a pipeline-software, as a ready-to-use FCM-based MRD-assessment tool for the daily clinical practice for patients with ALL. The new tool increases accuracy in assessment of FCM-MRD in samples which are difficult to analyse by conventional operator-based gating since computer-aided analysis potentially has a superior resolution due to utilization of the whole multi-parametric FCM-data space at once instead of step-wise, two-dimensional plot-based visualization. The system developed as a telemedical network reduces the work-load and lab-costs, staff-time needed for training, continuous quality control, operator-based data interpretation. It allows dissemination of automated FCM-MRD analysis to medical centres which have no established expertise for the benefit of an even larger community of diseased children worldwide. We established a telemedical network system for analysis and clinical follow-up and treatment monitoring of Leukaemia. The system is scalable and adapted to link several centres and laboratories worldwide.

Keywords: data security, flow cytometry, leukaemia, telematics platform, telemedicine

Procedia PDF Downloads 970
407 Characterization and Degradation of 3D Printed Polycaprolactone-Freeze Dried Bone Matrix Constructs for Use in Critical Sized Bone Defects

Authors: Samantha Meyr, Eman Mirdamadi, Martha Wang, Tao Lowe, Ryan Smith, Quinn Burke

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Critical-sized bone defects (CSD) treatment options remain a major clinical orthopedic challenge. They are uniquely contoured diseased or damaged bones and can be defined as those that will not heal spontaneously and require surgical intervention. Autografts are the current gold standard CSD treatment, which are histocompatible and provoke a minimal immunogenic response; however, they can cause donor site morbidity and will not suffice for the size required for replacement. As an alternative to traditional surgical methods, bone tissue engineering will be implemented via 3D printing methods. A freeze-dried bone matrix (FDBM) is a type of graft material available but will only function as desired when in the presence of bone growth factors. Polycaprolactone (PCL) is a known biodegradable material with good biocompatibility that has been proven manageable in 3D printing as a medical device. A 3D-extrusion printing strategy is introduced to print these materials into scaffolds for bone grafting purposes, which could be more accessible and rapid than the current standard. Mechanical, thermal, cytotoxic, and physical properties were investigated throughout a degradation period of 6 months using fibroblasts and dental pulp stem cells. PCL-FDBM scaffolds were successfully printed with high print fidelity in their respective pore sizes and allograft content. Additionally, we have created a method for evaluating PCL using differential scanning calorimetry (DSC) and have evaluated PCL degradation over roughly 6 months.

Keywords: 3D printing, bone tissue engineering, cytotoxicity, degradation, scaffolds

Procedia PDF Downloads 88
406 Formulation and Optimization of Topical 5-Fluorouracil Microemulsions Using Central Compisite Design

Authors: Sudhir Kumar, V. R. Sinha

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Water in oil topical microemulsions of 5-FU were developed and optimized using face centered central composite design. Topical w/o microemulsion of 5-FU were prepared using sorbitan monooleate (Span 80), polysorbate 80 (Tween 80), with different oils such as oleic acid (OA), triacetin (TA), and isopropyl myristate (IPM). The ternary phase diagrams designated the microemulsion region and face centered central composite design helped in determining the effects of selected variables viz. type of oil, smix ratio and water concentration on responses like drug content, globule size and viscosity of microemulsions. The CCD design exhibited that the factors have statistically significant effects (p<0.01) on the selected responses. The actual responses showed excellent agreement with the predicted values as suggested by the CCD with lower residual standard error. Similarly, the optimized values were found within the range as predicted by the model. Furthermore, other characteristics of microemulsions like pH, conductivity were investigated. For the optimized microemulsion batch, ex-vivo skin flux, skin irritation and retention studies were performed and compared with marketed 5-FU formulation. In ex vivo skin permeation studies, higher skin retention of drug and minimal flux was achieved for optimized microemulsion batch then the marketed cream. Results confirmed the actual responses to be in agreement with predicted ones with least residual standard errors. Controlled release of drug was achieved for the optimized batch with higher skin retention of 5-FU, which can further be utilized for the treatment of many dermatological disorders.

Keywords: 5-FU, central composite design, microemulsion, ternanry phase diagram

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405 Outdoor Physical Play as Critical to Early Childhood Development: Findings from Saudi Arabia

Authors: Rana S. Alghamdi

Abstract:

Play in early childhood education has been stifled across the world due to an overemphasis on academic achievement and a reduced focus on physical play and motor development. In Saudi Arabia, teachers reticent to allocate more time to play for fear of retribution from parents and administrators that children are losing academic seat time. This practice has proven to be detrimental to the social, emotional, physical, and cognitive development of children. Teachers are pressured to prioritize Arabic, math, and science while providing minimal time for physical activities. Administrators tend to push for an ever-increasing emphasis on academia in order to achieve higher test scores. However, young children often find it difficult to concentrate if they are not able to get out energy through physical play. Furthermore, many youth educators are not qualified to oversee physical activities, and many facilities are unprepared for safe, outdoor play. This results in children getting little to no outdoor activity. They are stuck in a strict academic regimen that may dampen the creativity and imagination easily fostered through cooperative play. For a stronger educational system and more well-rounded students, Saudi schools should enact policies that extend the number of required hours dedicated to outdoor and physical play. They should also offer training for unqualified teachers. This training should focus on the benefits of physical play and instruct them on how to facilitate these activities safely and effectively. School administrators must focus on providing adequate equipment and safe environments for the purpose of outdoor play and education. In doing so, they will be setting their students up for a successful future and improving their abilities in all aspects of education.

Keywords: early childhood education, play, outdoor, Saudi Arabia

Procedia PDF Downloads 138
404 Greenlight Laser Prostatectomy: A Safe and Effective Day Case Option for Bladder Outlet Obstruction in the Elderly Population

Authors: Gordon Weight, Hermione Tsoi, Patrick Cutinha, Sanjay Rajpal

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Aim: Greenlight-laser prostatectomy (GLLP) is becoming a popular treatment option for bladder outlet obstruction and lower urinary tract symptoms (LUTS). In this retrospective study, we aim to explore the patient selection, perioperative morbidity, and functional outcomes of GLLP. Methods: Patients who underwent GLLP at a UK tertiary centre between June 2018 and November 2021 were included in this study. Retrospective data covering patient demographics, perioperative parameters and postoperative outcomes were collected using the electronic records systems. Results: 305 patients were included in this study with a mean age of 73 (range 30-90) years. The most common indication (62.6%) for the procedure was patient’s wish to be free from long-term catheters (LTC) or intermittent catheterisation (ISC), followed by failed medical therapy for LUTS (36.4%). 84.6% of patients had an ASA ≥2, and 32.1% took anticoagulant or antiplatelet therapy. Inpatient stays were minimal, with the majority (68.2%) of patients were performed as day case, and only 10.5% of patients requiring more than a single night admission. The 3-month readmission rate was 10.8%, with the most common causes being haematuria and urinary-tract infection. The successful TWOC rate at follow up was 91.2%. Amongst the 19 patients who failed TWOC, 14 had LTC prior to the procedure and 4 had been performing ISC. Conclusions: Our study shows that GLLP is a safe and effective day case treatment and can be suitable for elderly and comorbid patients. Patients requiring LTC or ISC pre-operatively should be counselled carefully about the risk of not being catheter-free post procedure.

Keywords: urology, endourology, prostate, bladder outlet obstruction, laser

Procedia PDF Downloads 56
403 Gethuk Marillo: The New Product Development of Anti-Cancer Snacks Utilizing Xanthones and Anthocyanin in Mangosteen Pericarp and Tamarillo Fruit

Authors: Desi Meriyanti, Delina Puspa Rosana Firdaus, Ristia Rinati

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Nowadays, the presence of free radicals become a big concern due to its negative impact to the body, which can triggers the formation of degenerative diseases such as cancer, heart disease cardiovascular, diabetic mellitus and others. Free radical oxidation can be prevented by the presence of antioxidants. Naturally, the human body produces its own antioxidants. Because of the free radicals exposure are so intense, especially from the environment, it is necessary to supply antioxidants needed from outside, through the consumption of functional foods with high antioxidant content. Gethuk is one of the traditional snacks in Indonesia. Gethuk is made from cassava with minimal processing such as boiling, destructing, and forming. Gethuk is classified as a familiar snack in the community, so it has a potential for developing, especially into a functional food. The low content of antioxidants in gethuk can be overcome with the development of a product called Gethuk Marillo. Gethuk Marillo is gethuk with the addition of natural antioxidants from mangosteen pericarp extract which has a high content of xanthones, these compounds are classified into flavonoids and act as antioxidants in the body. Gethuk Marillo served along with tamarillo fruit sauce which is also high in antioxidants such as anthocyanin. The combination between 300 grams gethuk Marillo and sauce contain flavonoid about 31% of human antioxidant needs per day. Gethuk Marillo called as a functional food because of high flavonoids content which can prevent degenerative diseases namely cancer, as many studies that the xanthone and anthocyanins compounds can effectively prevent the formation of cancer cells in human body.

Keywords: Gethuk marillo, xanthones, anthocyanin, high antioxidants, anti-cancer

Procedia PDF Downloads 645
402 Modeling Loads Applied to Main and Crank Bearings in the Compression-Ignition Two-Stroke Engine

Authors: Marcin Szlachetka, Mateusz Paszko, Grzegorz Baranski

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This paper discusses the AVL EXCITE Designer simulation research into loads applied to main and crank bearings in the compression-ignition two-stroke engine. There was created a model of engine lubrication system which covers the part of this system related to particular nodes of a bearing system, i.e. a connection of main bearings in an engine block with a crankshaft, a connection of crank pins with a connecting rod. The analysis focused on the load given as a distribution of hydrodynamic oil film pressure corresponding different values of radial internal clearance. There was also studied the impact of gas force on minimal oil film thickness in main and crank bearings versus crankshaft rotational speed. Our model calculates oil film parameters, an oil film pressure distribution, an oil temperature change and dimensions of bearings as well as an oil temperature distribution on surfaces of bearing seats. Accordingly, it was possible to select, for example, a correct clearance for each of the node bearings. The research was performed for several values of engine crankshaft speed ranging from 800 RPM to 4000 RPM. Bearing oil pressure was changed according to engine speed ranging between 1 bar and 5 bar and an oil temperature of 90°C. The main bearing clearances made initially for the calculation and research were: 0.015 mm, 0.025 mm, 0.035 mm, 0.05 mm, 0.1 mm. The oil used for the research corresponded the SAE 5W-40 classification. The paper presents the selected research results referring to certain specific operating points and bearing radial internal clearances. Acknowledgement: This work has been realized in the cooperation with The Construction Office of WSK ‘PZL-KALISZ’ S.A. and is part of Grant Agreement No. POIR.01.02.00-00-0002/15 financed by the Polish National Centre for Research and Development.

Keywords: crank bearings, diesel engine, oil film, two-stroke engine

Procedia PDF Downloads 196
401 Access to Sexual Reproductive Health (SRH) Education and Services to Deaf Adolescents in Wakiso, Uganda - The Ugandan Perspective

Authors: Racheal Ayanga, Nancy Katumba Muwangala, Jane Babirye, Harriet Kivumbi

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Background: Deaf adolescents are vulnerable. Deafness limits their access to resources that are accessed by their hearing peers. There is minimal attention placed on the SRH needs of persons with disabilities, especially in developing countries. We sought to assess barriers to access of SRH education and services for deaf adolescents in Uganda. Methods: We performed a cross sectional study using a questionnaire on knowledge of and access to SRH education and services from a selected sample of deaf adolescents aged 13-19 years at Wakiso Secondary school for the deaf. A consecutive sample of eligible participants was asked to join the study after obtaining informed consent until the target sample size was reached. Results: From 01 Jul 2022 to 30 Jan 2023, 70 quantitative interviews were conducted. Participants’ mean age was 17 years, and 66% were female. 89% had heard about several components of SRH. 99% reported a need for education and services but had challenges with access 85% of the time. 54% reported receipt of education and services from government or private facilities, and the rest from friends, parents, siblings, teachers and the internet. Conclusion: Government needs to look into availing tailored, sustainable SRH education/services to deaf adolescents at health facilities and teach health workers sign language. SRH education to parents, teachers and communities of deaf adolescents improves access in hard-to-reach areas. Integration of services into routine health care is key in creating and improving models of access to wider communities of persons with disabilities to improve their mental health.

Keywords: sexual and reproductive health, deaf, adolescents, education, services, disabilities, mental health, hard-to-reach areas

Procedia PDF Downloads 69
400 Development of Noninvasive Method to Analyze Dynamic Changes of Matrix Stiffness and Elasticity Characteristics

Authors: Elena Petersen, Inna Kornienko, Svetlana Guryeva, Sergey Dobdin, Anatoly Skripal, Andrey Usanov, Dmitry Usanov

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One of the most important unsolved problems in modern medicine is the increase of chronic diseases that lead to organ dysfunction or even complete loss of function. Current methods of treatment do not result in decreased mortality and disability statistics. Currently, the best treatment for many patients is still transplantation of organs and/or tissues. Therefore, finding a way of correct artificial matrix biofabrication in case of limited number of natural organs for transplantation is a critical task. One important problem that needs to be solved is development of a nondestructive and noninvasive method to analyze dynamic changes of mechanical characteristics of a matrix with minimal side effects on the growing cells. This research was focused on investigating the properties of matrix as a marker of graft condition. In this study, the collagen gel with human primary dermal fibroblasts in suspension (60, 120, 240*103 cells/mL) and collagen gel with cell spheroids were used as model objects. The stiffness and elasticity characteristics were evaluated by a semiconductor laser autodyne. The time and cell concentration dependency of the stiffness and elasticity were investigated. It was shown that these properties changed in a non-linear manner with respect to cell concentration. The maximum matrix stiffness was observed in the collagen gel with the cell concentration of 120*103 cells/mL. This study proved the opportunity to use the mechanical properties of matrix as a marker of graft condition, which can be measured by noninvasive semiconductor laser autodyne technique.

Keywords: graft, matrix, noninvasive method, regenerative medicine, semiconductor laser autodyne

Procedia PDF Downloads 333
399 Development of a Novel Nanobiosystem for the Selective Nanophotothermolysis of Meticilin Resistant Staphyloccocous Aureus Using Anti-MRSA Antibody Functionalized Gold Nanoparticles

Authors: Lucian Mocan, Cristian Matea, Flaviu A. Tabaran, Teodora Mocan, Cornel Iancu

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Introduction: Due to antibiotic resistance, systemic infections caused by Meticilin resistant Staphyloccocous Aureus (MRSA) are the main cause of millions of deaths each year. Development of new active biomolecules that are highly effective and refractory to antibiotic resistance may open new avenues in the field of antimicrobial therapy. In this research, we have focused on the development of a novel nanobiosystem with high affinity for MRSA microorganism to mediate its selective laser thermal ablation. Materials and Methods: Gold nanoparticles (15nm in diameter) linked to a specific antibody against MRSA surface were selectively delivered (at various concentrations and incubation times) and internalized into MRSA microorganism following the treatment these multidrug-resistant bacteria were irradiated using a 2w, 808 nm LASER. Results and Discussions: The post-irradiation necrotic rate ranged from 51.2% (for 1 mg/L) to 87.3% (for 50 mg/L) at 60 seconds (p<0.001), while at 30 minute the necrotic rate increased from 64.3% (1 mg/L) to 92.1% (50 mg/L), p value<0.001. Significantly lower apoptotic rates were obtained in irradiated MRSA treated with GNPs only (control) treated for 60 seconds and 30 minutes at concentrations ranging from 1 mg/L to 50 mg/L. We show here that the optimal LASER mediated the necrotic effect of MRSA after incubation with anti-MRSA-Ab was obtained at a concentration of 50 mg/L. Conclusion: In the presented research, we obtained a very efficacious pulse laser mode treatment of individual MRSA agents with minimal effects on the surrounding medium, providing highly localized destruction only for MRSA microorganism.

Keywords: MRSA, photothermolysis, antibiotic resistance, gold nanoparticles

Procedia PDF Downloads 419