Search results for: joint load forces
217 Workflow Based Inspection of Geometrical Adaptability from 3D CAD Models Considering Production Requirements
Authors: Tobias Huwer, Thomas Bobek, Gunter Spöcker
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Driving forces for enhancements in production are trends like digitalization and individualized production. Currently, such developments are restricted to assembly parts. Thus, complex freeform surfaces are not addressed in this context. The need for efficient use of resources and near-net-shape production will require individualized production of complex shaped workpieces. Due to variations between nominal model and actual geometry, this can lead to changes in operations in Computer-aided process planning (CAPP) to make CAPP manageable for an adaptive serial production. In this context, 3D CAD data can be a key to realizing that objective. Along with developments in the geometrical adaptation, a preceding inspection method based on CAD data is required to support the process planner by finding objective criteria to make decisions about the adaptive manufacturability of workpieces. Nowadays, this kind of decisions is depending on the experience-based knowledge of humans (e.g. process planners) and results in subjective decisions – leading to a variability of workpiece quality and potential failure in production. In this paper, we present an automatic part inspection method, based on design and measurement data, which evaluates actual geometries of single workpiece preforms. The aim is to automatically determine the suitability of the current shape for further machining, and to provide a basis for an objective decision about subsequent adaptive manufacturability. The proposed method is realized by a workflow-based approach, keeping in mind the requirements of industrial applications. Workflows are a well-known design method of standardized processes. Especially in applications like aerospace industry standardization and certification of processes are an important aspect. Function blocks, providing a standardized, event-driven abstraction to algorithms and data exchange, will be used for modeling and execution of inspection workflows. Each analysis step of the inspection, such as positioning of measurement data or checking of geometrical criteria, will be carried out by function blocks. One advantage of this approach is its flexibility to design workflows and to adapt algorithms specific to the application domain. In general, within the specified tolerance range it will be checked if a geometrical adaption is possible. The development of particular function blocks is predicated on workpiece specific information e.g. design data. Furthermore, for different product lifecycle phases, appropriate logics and decision criteria have to be considered. For example, tolerances for geometric deviations are different in type and size for new-part production compared to repair processes. In addition to function blocks, appropriate referencing systems are important. They need to support exact determination of position and orientation of the actual geometries to provide a basis for precise analysis. The presented approach provides an inspection methodology for adaptive and part-individual process chains. The analysis of each workpiece results in an inspection protocol and an objective decision about further manufacturability. A representative application domain is the product lifecycle of turbine blades containing a new-part production and a maintenance process. In both cases, a geometrical adaptation is required to calculate individual production data. In contrast to existing approaches, the proposed initial inspection method provides information to decide between different potential adaptive machining processes.Keywords: adaptive, CAx, function blocks, turbomachinery
Procedia PDF Downloads 297216 Gender issues in Law and society in India
Authors: Sunil Gaikwad
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Gender discrimination is a very prevalent and much used word in the legal parlance. , The more socially, culturally, economically and educationally backward the community, the more gender discrimination is seen there. Gender discrimination is a worldwide Phenomena. In India it was more prevalent, due to illiteracy, bad social and religious customs. in Indian family system male child is considered as inheritor of the family clan, support for parents in their old age and girls as the property of others and unnecessary load on parents and on property as the dowry has to be give at her marriage as also some festivals like Raksha Bandhan and Bhau Teej during Deepawali (wherein having brother is compulsory)insist on having a male child in the family, hence most couples try to give birth only to male child at the cost of female child, hence the female feticide was going on a large scale due to which, sex ratio had considerably decreased creating problem for geeting groom for bride groom thereby putting question mark on family system. To redo the damage done to the society due to the female feticide Government of India has enacted various Laws and introduced various welfare schemes for the upliftment of girl child and also launched countrywide awareness campaign to create awareness among people about the importance of girl child and punitive laws for infanticide which is now bearing fruits but still cases of female feticide are coming fore. There is an urgent need to go to the roots of the problem and to find practicable and effective legal and social measures to overcome this issue, and the purpose of this research paper is the same. The research paper discusses in detail the reasons and superstitions that are responsible for the gender discriminations and comes out with effective measures including necessary and effective changes in the existing Laws, effective awareness campaign against religious superstitions for gender equality. For this research paper doctrinal research methodology is used to drive the research to its logical conclusion, for which various primary and secondary sources literature has been perused and studied. It is worth noting that while working on the paper suggestions and recommendations and conclusions have been drawn where it is suggested and concluded that there is an urgent need to re think about the festivals which encourages gender discriminations, to sensitize and create ample of awareness among people by effectively utilizing Radio, Television, Social Media folk arts, public shows and to make existing laws more effective and strict implementation for the purpose and zero tolerance for female feticide.Keywords: awareness, effective laws, female foeticide, festivals, superstitions
Procedia PDF Downloads 86215 Prevalence and Intensity of Soil Transmitted Helminth Infections among the School Children in the State of Uttar Pradesh, India
Authors: Prasanta Saini, Junaid Jibran Jawed, Subrata Majumdar
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Infections caused by soil-transmitted helminths (STH) are the major problem in all the nations of the world. The major focus of STH research is to study the prevalence of three major helminths, such as Ascaris, Trituris and hookworm. Here we are reporting the prevalence and intensity of the STH in the school children of the state of Uttar Pradesh, India. The aim of the study is to assess the prevalence and risk factors of STH infection among the school children, aged between 5-10 years in 27 districts randomly selected districts with covering nine agro-climatic zones of Uttar Pradesh, India. For this cross-sectional survey, we have selected the populations of government primary school going children in Uttar Pradesh. The sampling was performed in the nine different agro-climatic zones. Every individual of the study populations filled their daily information in the questioner's form and then the sample was collected and processed by kato-katz methods by following the guidelines of WHO. In this method, the sampling was performed in total of 6421 populations. A total of 6,421 children from 130 schools were surveyed. Infection with any soil-transmitted helminths was detected among 4,578 children with an overall prevalence of 75.6% (95% CI: 65.3-83.6). Among the 6421 population, the prevalence of Ascaris is 69.6% (95% CL 57.97-79.11), hookworm is 22.7% (95%CL 19.3-26.3) and Trichuris sp is 4.6% (95% CL 0.8-21.6), so the predicted prevalence map indicates that the STH infection was hyperendemic in this state. The findings of our survey in 130 schools covering 9 agro-climatic with one or more soil transmitted helminths. Majority of STH infections were of light intensity. STH infection was hyper-endemic in entire state, except three zones in western Uttar Pradesh. High prevalence ( > 75%) in all age groups also indicate little impact of existing deworming initiatives, including those among pre-school aged children. WHO recommends annual treatment in areas where STH prevalence is between 20% and 50%, and, a bi-annual treatment in areas with prevalence rates of over 50%. In view of high prevalence of STH infection in Uttar Pradesh, it is strongly recommended to initiate a deworming programme for school children in the state. Although our survey was among primary school children, high prevalence among children aged 4-6 years also indicates the need to strengthen the existing deworming programs for pre-school children. Extending the benefits of deworming to pre-school children through deworming in Anganwadi schools would further reduce to decrease the load of infection in community. As a long-term solution for control STH infection, it is also necessary to improve the sanitation levels in the area, as majority of the houses did not have latrines and most of the children were defecating in open fields, a factor that was found to be significantly associated with STH infection.Keywords: prevalence, school going children, soil transmitted helminthes, Uttar Pradesh-India
Procedia PDF Downloads 273214 Discrete PID and Discrete State Feedback Control of a Brushed DC Motor
Authors: I. Valdez, J. Perdomo, M. Colindres, N. Castro
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Today, digital servo systems are extensively used in industrial manufacturing processes, robotic applications, vehicles and other areas. In such control systems, control action is provided by digital controllers with different compensation algorithms, which are designed to meet specific requirements for a given application. Due to the constant search for optimization in industrial processes, it is of interest to design digital controllers that offer ease of realization, improved computational efficiency, affordable return rates, and ease of tuning that ultimately improve the performance of the controlled actuators. There is a vast range of options of compensation algorithms that could be used, although in the industry, most controllers used are based on a PID structure. This research article compares different types of digital compensators implemented in a servo system for DC motor position control. PID compensation is evaluated on its two most common architectures: PID position form (1 DOF), and PID speed form (2 DOF). State feedback algorithms are also evaluated, testing two modern control theory techniques: discrete state observer for non-measurable variables tracking, and a linear quadratic method which allows a compromise between the theoretical optimal control and the realization that most closely matches it. The compared control systems’ performance is evaluated through simulations in the Simulink platform, in which it is attempted to model accurately each of the system’s hardware components. The criteria by which the control systems are compared are reference tracking and disturbance rejection. In this investigation, it is considered that the accurate tracking of the reference signal for a position control system is particularly important because of the frequency and the suddenness in which the control signal could change in position control applications, while disturbance rejection is considered essential because the torque applied to the motor shaft due to sudden load changes can be modeled as a disturbance that must be rejected, ensuring reference tracking. Results show that 2 DOF PID controllers exhibit high performance in terms of the benchmarks mentioned, as long as they are properly tuned. As for controllers based on state feedback, due to the nature and the advantage which state space provides for modelling MIMO, it is expected that such controllers evince ease of tuning for disturbance rejection, assuming that the designer of such controllers is experienced. An in-depth multi-dimensional analysis of preliminary research results indicate that state feedback control method is more satisfactory, but PID control method exhibits easier implementation in most control applications.Keywords: control, DC motor, discrete PID, discrete state feedback
Procedia PDF Downloads 267213 In-situ Mental Health Simulation with Airline Pilot Observation of Human Factors
Authors: Mumtaz Mooncey, Alexander Jolly, Megan Fisher, Kerry Robinson, Robert Lloyd, Dave Fielding
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Introduction: The integration of the WingFactors in-situ simulation programme has transformed the education landscape at the Whittington Health NHS Trust. To date, there have been a total of 90 simulations - 19 aimed at Paediatric trainees, including 2 Child and Adolescent Mental Health (CAMHS) scenarios. The opportunity for joint debriefs provided by clinical faculty and airline pilots, has created a new exciting avenue to explore human factors within psychiatry. Through the use of real clinical environments and primed actors; the benefits of high fidelity simulation, interdisciplinary and interprofessional learning has been highlighted. The use of in-situ simulation within Psychiatry is a newly emerging concept and its success here has been recognised by unanimously positive feedback from participants and acknowledgement through nomination for the Health Service Journal (HSJ) Award (Best Education Programme 2021). Methodology: The first CAMHS simulation featured a collapsed patient in the toilet with a ligature tied around her neck, accompanied by a distressed parent. This required participants to consider:; emergency physical management of the case, alongside helping to contain the mother and maintaining situational awareness when transferring the patient to an appropriate clinical area. The second simulation was based on a 17- year- old girl attempting to leave the ward after presenting with an overdose, posing potential risk to herself. The safe learning environment enabled participants to explore techniques to engage the young person and understand their concerns, and consider the involvement of other members of the multidisciplinary team. The scenarios were followed by an immediate ‘hot’ debrief, combining technical feedback with Human Factors feedback from uniformed airline pilots and clinicians. The importance of psychological safety was paramount, encouraging open and honest contributions from all participants. Key learning points were summarized into written documents and circulated. Findings: The in-situ simulations demonstrated the need for practical changes both in the Emergency Department and on the Paediatric ward. The presence of airline pilots provided a novel way to debrief on Human Factors. The following key themes were identified: -Team-briefing (‘Golden 5 minutes’) - Taking a few moments to establish experience, initial roles and strategies amongst the team can reduce the need for conversations in front of a distressed patient or anxious relative. -Use of checklists / guidelines - Principles associated with checklist usage (control of pace, rigor, team situational awareness), instead of reliance on accurate memory recall when under pressure. -Read-back - Immediate repetition of safety critical instructions (e.g. drug / dosage) to mitigate the risks associated with miscommunication. -Distraction management - Balancing the risk of losing a team member to manage a distressed relative, versus it impacting on the care of the young person. -Task allocation - The value of the implementation of ‘The 5A’s’ (Availability, Address, Allocate, Ask, Advise), for effective task allocation. Conclusion: 100% of participants have requested more simulation training. Involvement of airline pilots has led to a shift in hospital culture, bringing to the forefront the value of Human Factors focused training and multidisciplinary simulation. This has been of significant value in not only physical health, but also mental health simulation.Keywords: human factors, in-situ simulation, inter-professional, multidisciplinary
Procedia PDF Downloads 108212 A Bottleneck-Aware Power Management Scheme in Heterogeneous Processors for Web Apps
Authors: Inyoung Park, Youngjoo Woo, Euiseong Seo
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With the advent of WebGL, Web apps are now able to provide high quality graphics by utilizing the underlying graphic processing units (GPUs). Despite that the Web apps are becoming common and popular, the current power management schemes, which were devised for the conventional native applications, are suboptimal for Web apps because of the additional layer, the Web browser, between OS and application. The Web browser running on a CPU issues GL commands, which are for rendering images to be displayed by the Web app currently running, to the GPU and the GPU processes them. The size and number of issued GL commands determine the processing load of the GPU. While the GPU is processing the GL commands, CPU simultaneously executes the other compute intensive threads. The actual user experience will be determined by either CPU processing or GPU processing depending on which of the two is the more demanded resource. For example, when the GPU work queue is saturated by the outstanding commands, lowering the performance level of the CPU does not affect the user experience because it is already deteriorated by the retarded execution of GPU commands. Consequently, it would be desirable to lower CPU or GPU performance level to save energy when the other resource is saturated and becomes a bottleneck in the execution flow. Based on this observation, we propose a power management scheme that is specialized for the Web app runtime environment. This approach incurs two technical challenges; identification of the bottleneck resource and determination of the appropriate performance level for unsaturated resource. The proposed power management scheme uses the CPU utilization level of the Window Manager to tell which one is the bottleneck if exists. The Window Manager draws the final screen using the processed results delivered from the GPU. Thus, the Window Manager is on the critical path that determines the quality of user experience and purely executed by the CPU. The proposed scheme uses the weighted average of the Window Manager utilization to prevent excessive sensitivity and fluctuation. We classified Web apps into three categories using the analysis results that measure frame-per-second (FPS) changes under diverse CPU/GPU clock combinations. The results showed that the capability of the CPU decides user experience when the Window Manager utilization is above 90% and consequently, the proposed scheme decreases the performance level of CPU by one step. On the contrary, when its utilization is less than 60%, the bottleneck usually lies in the GPU and it is desirable to decrease the performance of GPU. Even the processing unit that is not on critical path, excessive performance drop can occur and that may adversely affect the user experience. Therefore, our scheme lowers the frequency gradually, until it finds an appropriate level by periodically checking the CPU utilization. The proposed scheme reduced the energy consumption by 10.34% on average in comparison to the conventional Linux kernel, and it worsened their FPS by 1.07% only on average.Keywords: interactive applications, power management, QoS, Web apps, WebGL
Procedia PDF Downloads 192211 Stress Corrosion Crackings Test of Candidate Materials in Support of the Development of the European Small Modular Supercritical Water Cooled Rector Concept
Authors: Radek Novotny, Michal Novak, Daniela Marusakova, Monika Sipova, Hugo Fuentes, Peter Borst
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This research has been conducted within the European HORIZON 2020 project ECC-SMART. The main objective is to assess whether it is feasible to design and develop a small modular reactor (SMR) that would be cooled by supercritical water (SCW). One of the main objectives for material research concerns the corrosion of the candidate cladding materials. The experimental part has been conducted in support of the qualification procedure of the future SCW-SMR constructional materials. The last objective was to identify the gaps in current norms and guidelines. Apart from corrosion, resistance testing of candidate materials stresses corrosion cracking susceptibility tests have been performed in supercritical water. This paper describes part of these tests, in particular, those slow strain rate tensile loading applied for tangential ring shape specimens of two candidate materials, Alloy 800H and 310S stainless steel. These ring tensile tests are one the methods used for tensile testing of nuclear cladding. Here full circular heads with dimensions roughly equal to the inner diameter of the sample and the gage sections are placed in the parallel direction to the applied load. Slow strain rate tensile tests have been conducted in 380 or 500oC supercritical water applying two different elongation rates, 1x10-6 and 1x10-7 s-1. The effect of temperature and dissolved oxygen content on the SCC susceptibility of Alloy 800H and 310S stainless steel was investigated when two different temperatures and concentrations of dissolved oxygen were applied in supercritical water. The post-fracture analysis includes fractographic analysis of the fracture surfaces using SEM as well as cross-sectional analysis on the occurrence of secondary cracks. Assessment of the effect of environment and dissolved oxygen content was by comparing to the results of the reference tests performed in air and N2 gas overpressure. The effect of high temperature on creep and its role in the initiation of SCC was assessed as well. It has been concluded that the applied test method could be very useful for the investigation of stress corrosion cracking susceptibility of candidate cladding materials in supercritical water.Keywords: stress corrosion cracking, ring tensile tests, super-critical water, alloy 800H, 310S stainless steel
Procedia PDF Downloads 87210 Transport Mode Selection under Lead Time Variability and Emissions Constraint
Authors: Chiranjit Das, Sanjay Jharkharia
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This study is focused on transport mode selection under lead time variability and emissions constraint. In order to reduce the carbon emissions generation due to transportation, organization has often faced a dilemmatic choice of transport mode selection since logistic cost and emissions reduction are complementary with each other. Another important aspect of transportation decision is lead-time variability which is least considered in transport mode selection problem. Thus, in this study, we provide a comprehensive mathematical based analytical model to decide transport mode selection under emissions constraint. We also extend our work through analysing the effect of lead time variability in the transport mode selection by a sensitivity analysis. In order to account lead time variability into the model, two identically normally distributed random variables are incorporated in this study including unit lead time variability and lead time demand variability. Therefore, in this study, we are addressing following questions: How the decisions of transport mode selection will be affected by lead time variability? How lead time variability will impact on total supply chain cost under carbon emissions? To accomplish these objectives, a total transportation cost function is developed including unit purchasing cost, unit transportation cost, emissions cost, holding cost during lead time, and penalty cost for stock out due to lead time variability. A set of modes is available to transport each node, in this paper, we consider only four transport modes such as air, road, rail, and water. Transportation cost, distance, emissions level for each transport mode is considered as deterministic and static in this paper. Each mode is having different emissions level depending on the distance and product characteristics. Emissions cost is indirectly affected by the lead time variability if there is any switching of transport mode from lower emissions prone transport mode to higher emissions prone transport mode in order to reduce penalty cost. We provide a numerical analysis in order to study the effectiveness of the mathematical model. We found that chances of stock out during lead time will be higher due to the higher variability of lead time and lad time demand. Numerical results show that penalty cost of air transport mode is negative that means chances of stock out zero, but, having higher holding and emissions cost. Therefore, air transport mode is only selected when there is any emergency order to reduce penalty cost, otherwise, rail and road transport is the most preferred mode of transportation. Thus, this paper is contributing to the literature by a novel approach to decide transport mode under emissions cost and lead time variability. This model can be extended by studying the effect of lead time variability under some other strategic transportation issues such as modal split option, full truck load strategy, and demand consolidation strategy etc.Keywords: carbon emissions, inventory theoretic model, lead time variability, transport mode selection
Procedia PDF Downloads 434209 The Emerging Post-Islamism and the Politics of Pakistan’s Jamaat-i-Islami in the Contemporary Muslim World
Authors: Shahzada Gulfam
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Islamism was considered as a new phenomenon in Muslim World to revolt against static Religious Traditionalists and the Imperialists. Islamist political parties viewed the establishment of an Islamic state within the limits of Sharia’h as their destination. The Islamists movements like Ikhwan-ul Muslimun, Jamaat-i-Islami etc. did appear with revolutionary agenda but were contained by military forces and the secular modernists of Muslim World. The Muslim rulers, historically could not respect the democratic and moral norms and equally emerged as dictators in democracies, military rule as well as in monarchies. The Arab Spring did not follow the Islamists agenda but gathered the common masses against the corrupt rulers to have a just democratic political system. The Islamic State and Sharia’h were not their immediate targets but the achievement of moral norms in Muslim societies and eradication of dictatorial rule were the basic aims. This phenomenon is named as post-Islamism. The political struggle of PAT (Pakistan Awami Tehreek) and the PTI (Pakistan Tehreek-i-Insaf) has been following the footsteps of Arab Spring and can be noted as the extension of Arab Spring in Muslim World. The results of this struggle would define the fate of Post-Islamism in Pakistan. Has Jamaat-i-Islami got the potential to reform its agenda accordingly? This paper intends to study the Jamaat’s struggle and tries to predict Jamaat’s role in post-Islamism scenario. There is a clear distinction between the people of religion and the people following the popular materialistic westernized value system. This division is also evident in political parties. Pakistan has been ruled mostly by the secular parties and rulers. The inability to establish Islamic system by replacing the imperial system has created militancy and revolt which requires the establishment of a sound model Islamic based system in the country. The political parties of Pakistan could not device a modernize agenda, equally acceptable in modernized world and addressing the prevailing issues and also having the indigenous religious and cultural roots. The inability of Jamaat-i-Islami Pakistan to transform its agenda accordingly to serve the post-Islamism has made it irrelevant in Pakistan’s politics. Once Jamaat leaves behind its hard position as an Islamist party and accepts the post-Islamism as beginning to create its idealized state and society, it can pursue its agenda gradually. The phenomenon of post-Islamism does not make Islamists irrelevant but invites them to listen to the priorities of masses rather than insisting on the agenda of their respective ideologues to be followed for all times. The ruling Muslim democrats and military dictators of Pakistan have been following unfair means to sustain their political power which gave rise to space for the new political parties to emerge and organize agitation successfully in Pakistani Politics. Jamaat-i-Islami could not fill that space to be an agent of Post-Islamism and could not break their chains which had been tying them to the prevailing failed democracy of Pakistan. Post-Islamists are the addressers of the rulers corruption and are struggling for reforms in system. Jamaat due to its ideological compulsions could not transform its agenda accordingly. The new scenario indicates that the Post-Islamism which emerged in Arab World can be taken as first step to establish democracy and justice in state and society and then the establishment of Islamic law and the establishment of an Islamic state should have been the next targets. This gradual agenda would have delivered public support to the Jamaat which deserved that but PTI & PAT have cashed this opportunity in Pakistani politics by strengthening their respective vote banks.Keywords: arab spring, islamic state, islamic political parties, muslim world, post-islamism
Procedia PDF Downloads 368208 The Role of a Specialized Diet for Management of Fibromyalgia Symptoms: A Systematic Review
Authors: Siddhant Yadav, Rylea Ranum, Hannah Alberts, Abdul Kalaiger, Brent Bauer, Ryan Hurt, Ann Vincent, Loren Toussaint, Sanjeev Nanda
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Background and significance: Fibromyalgia (FM) is a chronic pain disorder also characterized by chronic fatigue, morning stiffness, sleep, and cognitive symptoms, psychological disturbances (anxiety, depression), and is comorbid with multiple medical and psychiatric conditions. It has an incidence of 2-4% in the general population and is reported more commonly in women. Oxidative stress and inflammation are thought to contribute to pain in patients with FM, and the adoption of an antioxidant/anti-inflammatory diet has been suggested as a modality to alleviate symptoms. The aim of this systematic review was to evaluate the efficacy of specialized diets (ketogenic, gluten free, Mediterranean, and low carbohydrate) in improving FM symptoms. Methodology: A comprehensive search of the following databases from inception to July 15th, 2021, was conducted: Ovid MEDLINE and Epub ahead of print, in-process and other non-indexed citations and daily, Ovid Embase, Ovid EBM reviews, Cochrane central register of controlled trials, EBSCO host CINAHL with full text, Elsevier Scopus, website and citation index, web of science emerging sources citation and clinicaltrials.gov. We included randomized controlled trials, non-randomized experimental studies, cross-sectional studies, cohort studies, case series, and case reports in adults with fibromyalgia. The risk of bias was assessed with the Agency for Health Care Research and Quality designed, specific recommended criteria (AHRQ). Results: Thirteen studies were eligible for inclusion. This included a total of 761 participants. Twelve out of the 13 studies reported improvement in widespread body pain, joint stiffness, sleeping pattern, mood, and gastrointestinal symptoms, and one study reported no changes in symptomatology in patients with FM on specialized diets. None of the studies showed the worsening of symptoms associated with a specific diet. Most of the patient population was female, with the mean age at which fibromyalgia was diagnosed being 48.12 years. Improvement in symptoms was reported by the patient's adhering to a gluten-free diet, raw vegan diet, tryptophan- and magnesium-enriched Mediterranean diet, aspartame- and msg- elimination diet, and specifically a Khorasan wheat diet. Risk of bias assessment noted that 6 studies had a low risk of bias (5 clinical trials and 1 case series), four studies had a moderate risk of bias, and 3 had a high risk of bias. In many of the studies, the allocation of treatment (diets) was not adequately concealed, and the researchers did not rule out any potential impact from a concurrent intervention or an unintended exposure that might have biased the results. On the other hand, there was a low risk of attrition bias in all the trials; all were conducted with an intention-to-treat, and the inclusion/exclusion criteria, exposures/interventions, and primary outcomes were valid, reliable, and implemented consistently across all study participants. Concluding statement: Patients with fibromyalgia who followed specialized diets experienced a variable degree of improvement in their widespread body pain. Improvement was also seen in stiffness, fatigue, moods, sleeping patterns, and gastrointestinal symptoms. Additionally, the majority of the patients also reported improvement in overall quality of life.Keywords: fibromyalgia, specialized diet, vegan, gluten free, Mediterranean, systematic review
Procedia PDF Downloads 73207 The Production of Reinforced Insulation Bricks out of the Concentration of Ganoderma lucidum Fungal Inoculums and Cement Paste
Authors: Jovie Esquivias Nicolas, Ron Aldrin Lontoc Austria, Crisabelle Belleza Bautista, Mariane Chiho Espinosa Bundalian, Owwen Kervy Del Rosario Castillo, Mary Angelyn Mercado Dela Cruz, Heinrich Theraja Recana De Luna, Chriscell Gipanao Eustaquio, Desiree Laine Lauz Gilbas, Jordan Ignacio Legaspi, Larah Denise David Madrid, Charles Linelle Malapote Mendoza, Hazel Maxine Manalad Reyes, Carl Justine Nabora Saberdo, Claire Mae Rendon Santos
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In response to the global race in discovering the next advanced sustainable material that will reduce our ecological footprint, the researchers aimed to create a masonry unit which is competent in physical edifices and other constructional facets. From different proven researches, mycelium has been concluded that when dried can be used as a robust and waterproof building material that can be grown into explicit forms, thus reducing the processing requirements. Hypothesizing inclusive measures to attest fungi’s impressive structural qualities and absorbency, the researchers projected to perform comparative analyses in creating mycelium bricks from mushroom spores of G. lucidum. Three treatments were intended to classify the most ideal concentration of clay and substrate fixings. The substrate bags fixed with 30% clay and 70% mixings indicated highest numerical frequencies in terms of full occupation of fungal mycelia. Subsequently, sorted parts of white portions from the treatment were settled in a thermoplastic mold and burnt. Three proportional concentrations of cultivated substrate and cement were also prioritized to gather results of variation focused on the weights of the bricks in the Water Absorption Test and Durability Test. Fungal inoculums with solutions of cement showed small to moderate amounts of decrease and increase in load. This proves that the treatments did not show any significant difference when it comes to strength, efficiency and absorption capacity. Each of the concentration is equally valid and could be used in supporting the worldwide demands of creating numerous bricks while also taking into consideration the recovery of our nature.Keywords: mycelium, fungi, fungal mycelia, durability test, water absorption test
Procedia PDF Downloads 136206 Nanocarriers Made of Amino Acid Based Biodegradable Polymers: Poly(Ester Amide) and Related Cationic and PEGylating Polymers
Authors: Sophio Kobauri, Temur Kantaria, Nina Kulikova, David Tugushi, Ramaz Katsarava
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Polymeric nanoparticles-based drug delivery systems and therapeutics have a great potential in the treatment of a numerous diseases, due to they are characterizing the flexible properties which is giving possibility to modify their structures with a complex definition over their structures, compositions and properties. Important characteristics of the polymeric nanoparticles (PNPs) used as drug carriers are high particle’s stability, high carrier capacity, feasibility of encapsulation of both hydrophilic and hydrophobic drugs, and feasibility of variable routes of administration, including oral application and inhalation; NPs are especially effective for intracellular drug delivery since they penetrate into the cells’ interior though endocytosis. A variety of PNPs based drug delivery systems including charged and neutral, degradable and non-degradable polymers of both natural and synthetic origin have been developed. Among these huge varieties the biodegradable PNPs which can be cleared from the body after the fulfillment of their function could be considered as one of the most promising. For intracellular uptake it is highly desirable to have positively charged PNPs since they can penetrate deep into cell membranes. For long-lasting circulation of PNPs in the body it is important they have so called “stealth coatings” to protect them from the attack of immune system of the organism. One of the effective ways to render the PNPs “invisible” for immune system is their PEGylation which represent the process of pretreatment of polyethylene glycol (PEG) on the surface of PNPs. The present work deals with constructing PNPs from amino acid based biodegradable polymers – regular poly(ester amide) (PEA) composed of sebacic acid, leucine and 1,6-hexandiol (labeled as 8L6), cationic PEA composed of sebacic acid, arginine and 1,6-hexandiol (labeled as 8R6), and comb-like co-PEA composed of sebacic acid, malic acid, leucine and 1,6-hexandiol (labeled as PEG-PEA). The PNPs were fabricated using the polymer deposition/solvent displacement (nanoprecipitation) method. The regular PEA 8L6 form stable negatively charged (zeta-potential within 2-12 mV) PNPs of desired size (within 150-200 nm) in the presence of various surfactants (Tween 20, Tween 80, Brij 010, etc.). Blending the PEAs 8L6 and 8R6 gave the 130-140 nm sized positively charged PNPs having zeta-potential within +20 ÷ +28 mV depending 8L6/8R6 ratio. The PEGylating PEA PEG-PEA was synthesized by interaction of epoxy-co-PEA [8L6]0,5-[tES-L6]0,5 with mPEG-amine-2000 The stable and positively charged PNPs were fabricated using pure PEG-PEA as a surfactant. A firm anchoring of the PEG-PEA with 8L6/8R6 based PNPs (owing to a high afinity of the backbones of all three PEAs) provided good stabilization of the NPs. In vitro biocompatibility study of the new PNPs with four different stable cell lines: A549 (human), U-937 (human), RAW264.7 (murine), Hepa 1-6 (murine) showed they are biocompatible. Considering high stability and cell compatibility of the elaborated PNPs one can conclude that they are promising for subsequent therapeutic applications. This work was supported by the joint grant from the Science and Technology Center in Ukraine and Shota Rustaveli National Science Foundation of Georgia #6298 “New biodegradable cationic polymers composed of arginine and spermine-versatile biomaterials for various biomedical applications”.Keywords: biodegradable poly(ester amide)s, cationic poly(ester amide), pegylating poly(ester amide), nanoparticles
Procedia PDF Downloads 121205 Process Improvement and Redesign of the Immuno Histology (IHC) Lab at MSKCC: A Lean and Ergonomic Study
Authors: Samantha Meyerholz
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MSKCC offers patients cutting edge cancer care with the highest quality standards. However, many patients and industry members do not realize that the operations of the Immunology Histology Lab (IHC) are the backbone for carrying out this mission. The IHC lab manufactures blocks and slides containing critical tissue samples that will be read by a Pathologist to diagnose and dictate a patient’s treatment course. The lab processes 200 requests daily, leading to the generation of approximately 2,000 slides and 1,100 blocks each day. Lab material is transported through labeling, cutting, staining and sorting manufacturing stations, while being managed by multiple techs throughout the space. The quality of the stain as well as wait times associated with processing requests, is directly associated with patients receiving rapid treatments and having a wider range of care options. This project aims to improve slide request turnaround time for rush and non-rush cases, while increasing the quality of each request filled (no missing slides or poorly stained items). Rush cases are to be filled in less than 24 hours, while standard cases are allotted a 48 hour time period. Reducing turnaround times enable patients to communicate sooner with their clinical team regarding their diagnosis, ultimately leading faster treatments and potentially better outcomes. Additional project goals included streamlining tech and material workflow, while reducing waste and increasing efficiency. This project followed a DMAIC structure with emphasis on lean and ergonomic principles that could be integrated into an evolving lab culture. Load times and batching processes were analyzed using process mapping, FMEA analysis, waste analysis, engineering observation, 5S and spaghetti diagramming. Reduction of lab technician movement as well as their body position at each workstation was of top concern to pathology leadership. With new equipment being brought into the lab to carry out workflow improvements, screen and tool placement was discussed with the techs in focus groups, to reduce variation and increase comfort throughout the workspace. 5S analysis was completed in two phases in the IHC lab, helping to drive solutions that reduced rework and tech motion. The IHC lab plans to continue utilizing these techniques to further reduce the time gap between tissue analysis and cancer care.Keywords: engineering, ergonomics, healthcare, lean
Procedia PDF Downloads 223204 The Procedural Sedation Checklist Manifesto, Emergency Department, Jersey General Hospital
Authors: Jerome Dalphinis, Vishal Patel
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The Bailiwick of Jersey is an island British crown dependency situated off the coast of France. Jersey General Hospital’s emergency department sees approximately 40,000 patients a year. It’s outside the NHS, with secondary care being free at the point of care. Sedation is a continuum which extends from a normal conscious level to being fully unresponsive. Procedural sedation produces a minimally depressed level of consciousness in which the patient retains the ability to maintain an airway, and they respond appropriately to physical stimulation. The goals of it are to improve patient comfort and tolerance of the procedure and alleviate associated anxiety. Indications can be stratified by acuity, emergency (cardioversion for life-threatening dysrhythmia), and urgency (joint reduction). In the emergency department, this is most often achieved using a combination of opioids and benzodiazepines. Some departments also use ketamine to produce dissociative sedation, a cataleptic state of profound analgesia and amnesia. The response to pharmacological agents is highly individual, and the drugs used occasionally have unpredictable pharmacokinetics and pharmacodynamics, which can always result in progression between levels of sedation irrespective of the intention. Therefore, practitioners must be able to ‘rescue’ patients from deeper sedation. These practitioners need to be senior clinicians with advanced airway skills (AAS) training. It can lead to adverse effects such as dangerous hypoxia and unintended loss of consciousness if incorrectly undertaken; studies by the National Confidential Enquiry into Patient Outcome and Death (NCEPOD) have reported avoidable deaths. The Royal College of Emergency Medicine, UK (RCEM) released an updated ‘Safe Sedation of Adults in the Emergency Department’ guidance in 2017 detailing a series of standards for staff competencies, and the required environment and equipment, which are required for each target sedation depth. The emergency department in Jersey undertook audit research in 2018 to assess their current practice. It showed gaps in clinical competency, the need for uniform care, and improved documentation. This spurred the development of a checklist incorporating the above RCEM standards, including contraindication for procedural sedation and difficult airway assessment. This was approved following discussion with the relevant heads of departments and the patient safety directorates. Following this, a second audit research was carried out in 2019 with 17 completed checklists (11 relocation of joints, 6 cardioversions). Data was obtained from looking at the controlled resuscitation drugs book containing documented use of ketamine, alfentanil, and fentanyl. TrakCare, which is the patient electronic record system, was then referenced to obtain further information. The results showed dramatic improvement compared to 2018, and they have been subdivided into six categories; pre-procedure assessment recording of significant medical history and ASA grade (2 fold increase), informed consent (100% documentation), pre-oxygenation (88%), staff (90% were AAS practitioners) and monitoring (92% use of non-invasive blood pressure, pulse oximetry, capnography, and cardiac rhythm monitoring) during procedure, and discharge instructions including the documented return of normal vitals and consciousness (82%). This procedural sedation checklist is a safe intervention that identifies pertinent information about the patient and provides a standardised checklist for the delivery of gold standard of care.Keywords: advanced airway skills, checklist, procedural sedation, resuscitation
Procedia PDF Downloads 117203 Design Charts for Strip Footing on Untreated and Cement Treated Sand Mat over Underlying Natural Soft Clay
Authors: Sharifullah Ahmed, Sarwar Jahan Md. Yasin
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Shallow foundations on unimproved soft natural soils can undergo a high consolidation and secondary settlement. For low and medium rise building projects on such soil condition, pile foundation may not be cost effective. In such cases an alternative to pile foundations may be shallow strip footings placed on a double layered improved soil system soil. The upper layer of this system is untreated or cement treated compacted sand and underlying layer is natural soft clay. This system will reduce the settlement to an allowable limit. The current research has been conducted with the settlement of a rigid plane-strain strip footing of 2.5 m width placed on the surface of a soil consisting of an untreated or cement treated sand layer overlying a bed of homogeneous soft clay. The settlement of the mentioned shallow foundation has been studied considering both cases with the thicknesses of the sand layer are 0.3 to 0.9 times the width of footing. The response of the clay layer is assumed as undrained for plastic loading stages and drained during consolidation stages. The response of the sand layer is drained during all loading stages. FEM analysis was done using PLAXIS 2D Version 8.0. A natural clay deposit of 15 m thickness and 18 m width has been modeled using Hardening Soil Model, Soft Soil Model, Soft Soil Creep Model, and upper improvement layer has been modeled using only Hardening Soil Model. The groundwater level is at the top level of the clay deposit that made the system fully saturated. Parametric study has been conducted to determine the effect of thickness, density, cementation of the sand mat and density, shear strength of the soft clay layer on the settlement of strip foundation under the uniformly distributed vertical load of varying value. A set of the chart has been established for designing shallow strip footing on the sand mat over thick, soft clay deposit through obtaining the particular thickness of sand mat for particular subsoil parameter to ensure no punching shear failure and no settlement beyond allowable level. Design guideline in the form of non-dimensional charts has been developed for footing pressure equivalent to medium-rise residential or commercial building foundation with strip footing on soft inorganic Normally Consolidated (NC) soil of Bangladesh having void ratio from 1.0 to 1.45.Keywords: design charts, ground improvement, PLAXIS 2D, primary and secondary settlement, sand mat, soft clay
Procedia PDF Downloads 123202 A pilot Study of Umbilical Cord Mini-Clamp
Authors: Seng Sing Tan
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Clamping of the umbilical cord after birth is widely practiced as a part of labor management. Further improvements were proposed to produce a smaller, lighter and more comfortable clamp while still maintaining current standards of clamping. A detachable holder was also developed to facilitate the clamping process. This pilot study on the efficacy of the mini-clamp was conducted to evaluate a tightness of the seal and a firm grip of the clamp on the umbilical cord. The study was carried out at National University Hospital, using 5 sets of placental cord. 18 samples of approximate 10 cm each were harvested. The test results showed that the mini-clamp was able to stop the flow through the cord after clamping without rupturing the cord. All slip tests passed with a load of 0.2 kg. In the pressure testing, 30kPa of saline was exerted into the umbilical veins. Although there was no physical sign of fluid leaking through the end secured by the mini-clamp, the results showed the pressure was not able to sustain the pressure set during the tests. 12 out of the 18 test samples have more than 7% of pressure drop in 30 seconds. During the pressure leak test, it was observed on several samples that when pressurized, small droplets of saline were growing on the outer surface of the cord lining membrane. It was thus hypothesized that the pressure drop was likely caused by the perfusion of the injected saline through the Wharton’s jelly and the cord lining membrane. The average pressure in the umbilical vein is roughly 2.67kPa (20 mmHg), less than 10% of 30kPa (~225mmHg), set for the pressure testing. As such, the pressure set could be over-specified, leading to undesirable outcomes. The development of the mini-clamp was an attempt to increase the comfort of newly born babies while maintaining the usability and efficacy of hospital grade umbilical cord clamp. The pressure leak in this study would be unfair to fully attribute it to the design and efficacy of the mini-clamp. Considering the unexpected leakage of saline through the umbilical membrane due to over-specified pressure exerted on the umbilical veins, improvements can definitely be made to the existing experimental setup to obtain a more accurate and conclusive outcome. If proven conclusive and effective, the mini-clamp with a detachable holder could be a smaller and potentially cheaper alternative to existing umbilical cord clamps. In addition, future clinical trials could be conducted to determine the user-friendliness of the mini-clamp and evaluate its practicality in the clinical setting by labor ward clinicians. A further potential improvement could be proposed on the sustainability factor of the mini-clamp. A biodegradable clamp would revolutionise the industry in this increasingly environmentally sustainability world.Keywords: leak test, mini-clamp, slip test, umbilical cord
Procedia PDF Downloads 132201 Adjustment of the Level of Vibrational Force on Targeted Teeth
Authors: Amin Akbari, Dongcai Wang, Huiru Li, Xiaoping Du, Jie Chen
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The effect of vibrational force (VF) on accelerating orthodontic tooth movement depends on the level of delivered stimulation to the tooth in terms of peak load (PL), which requires contacts between the tooth and the VF device. A personalized device ensures the contacts, but the resulting PL distribution on the teeth is unknown. Furthermore, it is unclear whether the PL on particular teeth can be adjusted to the prescribed values. The objective of this study was to investigate the efficacy of apersonalized VF device in controlling the level of stimulation on two teeth, the mandibular canines and 2nd molars. A 3-D finite element (FE) model of human dentition, including teeth, PDL, and alveolar bone, was created from the cone beam computed tomography images of an anonymous subject. The VF was applied to the teeth through a VFdevice consisting of a mouthpiece with engraved tooth profile of the subject and a VF source that applied 0.3 N force with the frequency of 30 Hz. The dentition and mouthpiece were meshed using 10-node tetrahedral elements. Interface elements were created at the interfaces between the teeth and the mouthpiece. The upper and lower teeth bite on the mouthpiece to receive the vibration. The depth of engraved individual tooth profile could be adjusted, which was accomplished by adding a layer of material as an interference or removing a layer of material as a clearance to change the PL on the tooth. The interference increases the PL while the clearance decreases it. Fivemouthpiece design cases were simulated, which included a mouthpiece without interference/clearance; the mouthpieces with bilateral interferences on both mandibular canines and 2nd molars with magnitudes of 0.1, 0.15, and 0.2-mm, respectively; and mouthpiece with bilateral 0.3-mm clearances on the four teeth. Then, the force distributions on the entire dentition were compared corresponding to these adjustments. The PL distribution on the teeth is uneven when there is no interference or clearance. Among all teeth, the anterior segment receives the highest level of PL. Adding 0.1, 0.15, and 0.2-mm interferences to the canines and 2nd molars bilaterally leads to increase of the PL on the canines by 10, 62, and 73 percent and on the 2nd molar by 14, 55, and 87 percent, respectively. Adding clearances to the canines and 2nd molars by removing the contactsbetween these teeth and the mouthpiece results in zero PL on them. Moreover, introducing interference to mandibular canines and 2nd molarsredistributes the PL on the entireteeth. The share of the PL on the anterior teeth are reduced. The use of the personalized mouthpiece ensures contactsof the teeth to the mouthpiece so that all teeth can be stimulated. However, the PL distribution is uneven. Adding interference between a tooth and the mouthpiece increases the PL while introducing clearance decreases the PL. As a result, the PL is redistributed. This study confirms that the level of VF stimulation on the individual tooth can be adjusted to a prescribed value.Keywords: finite element method, orthodontic treatment, stress analysis, tooth movement, vibrational force
Procedia PDF Downloads 224200 Improving Data Completeness and Timely Reporting: A Joint Collaborative Effort between Partners in Health and Ministry of Health in Remote Areas, Neno District, Malawi
Authors: Wiseman Emmanuel Nkhomah, Chiyembekezo Kachimanga, Moses Banda Aron, Julia Higgins, Manuel Mulwafu, Kondwani Mpinga, Mwayi Chunga, Grace Momba, Enock Ndarama, Dickson Sumphi, Atupere Phiri, Fabien Munyaneza
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Background: Data is key to supporting health service delivery as stakeholders, including NGOs rely on it for effective service delivery, decision-making, and system strengthening. Several studies generated debate on data quality from national health management information systems (HMIS) in sub-Saharan Africa. This limits the utilization of data in resource-limited settings, which already struggle to meet standards set by the World Health Organization (WHO). We aimed to evaluate data quality improvement of Neno district HMIS over a 4-year period (2018 – 2021) following quarterly data reviews introduced in January 2020 by the district health management team and Partners In Health. Methods: Exploratory Mixed Research was used to examine report rates, followed by in-depth interviews using Key Informant Interviews (KIIs) and Focus Group Discussions (FGDs). We used the WHO module desk review to assess the quality of HMIS data in the Neno district captured from 2018 to 2021. The metrics assessed included the completeness and timeliness of 34 reports. Completeness was measured as a percentage of non-missing reports. Timeliness was measured as the span between data inputs and expected outputs meeting needs. We computed T-Test and recorded P-values, summaries, and percentage changes using R and Excel 2016. We analyzed demographics for key informant interviews in Power BI. We developed themes from 7 FGDs and 11 KIIs using Dedoose software, from which we picked perceptions of healthcare workers, interventions implemented, and improvement suggestions. The study was reviewed and approved by Malawi National Health Science Research Committee (IRB: 22/02/2866). Results: Overall, the average reporting completeness rate was 83.4% (before) and 98.1% (after), while timeliness was 68.1% and 76.4 respectively. Completeness of reports increased over time: 2018, 78.8%; 2019, 88%; 2020, 96.3% and 2021, 99.9% (p< 0.004). The trend for timeliness has been declining except in 2021, where it improved: 2018, 68.4%; 2019, 68.3%; 2020, 67.1% and 2021, 81% (p< 0.279). Comparing 2021 reporting rates to the mean of three preceding years, both completeness increased from 88% to 99% (in 2021), while timeliness increased from 68% to 81%. Sixty-five percent of reports have maintained meeting a national standard of 90%+ in completeness while only 24% in timeliness. Thirty-two percent of reports met the national standard. Only 9% improved on both completeness and timeliness, and these are; cervical cancer, nutrition care support and treatment, and youth-friendly health services reports. 50% of reports did not improve to standard in timeliness, and only one did not in completeness. On the other hand, factors associated with improvement included improved communications and reminders using internal communication, data quality assessments, checks, and reviews. Decentralizing data entry at the facility level was suggested to improve timeliness. Conclusion: Findings suggest that data quality in HMIS for the district has improved following collaborative efforts. We recommend maintaining such initiatives to identify remaining quality gaps and that results be shared publicly to support increased use of data. These results can inform Ministry of Health and its partners on some interventions and advise initiatives for improving its quality.Keywords: data quality, data utilization, HMIS, collaboration, completeness, timeliness, decision-making
Procedia PDF Downloads 84199 Integrated Mathematical Modeling and Advance Visualization of Magnetic Nanoparticle for Drug Delivery, Drug Release and Effects to Cancer Cell Treatment
Authors: Norma Binti Alias, Che Rahim Che The, Norfarizan Mohd Said, Sakinah Abdul Hanan, Akhtar Ali
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This paper discusses on the transportation of magnetic drug targeting through blood within vessels, tissues and cells. There are three integrated mathematical models to be discussed and analyze the concentration of drug and blood flow through magnetic nanoparticles. The cell therapy brought advancement in the field of nanotechnology to fight against the tumors. The systematic therapeutic effect of Single Cells can reduce the growth of cancer tissue. The process of this nanoscale phenomena system is able to measure and to model, by identifying some parameters and applying fundamental principles of mathematical modeling and simulation. The mathematical modeling of single cell growth depends on three types of cell densities such as proliferative, quiescent and necrotic cells. The aim of this paper is to enhance the simulation of three types of models. The first model represents the transport of drugs by coupled partial differential equations (PDEs) with 3D parabolic type in a cylindrical coordinate system. This model is integrated by Non-Newtonian flow equations, leading to blood liquid flow as the medium for transportation system and the magnetic force on the magnetic nanoparticles. The interaction between the magnetic force on drug with magnetic properties produces induced currents and the applied magnetic field yields forces with tend to move slowly the movement of blood and bring the drug to the cancer cells. The devices of nanoscale allow the drug to discharge the blood vessels and even spread out through the tissue and access to the cancer cells. The second model is the transport of drug nanoparticles from the vascular system to a single cell. The treatment of the vascular system encounters some parameter identification such as magnetic nanoparticle targeted delivery, blood flow, momentum transport, density and viscosity for drug and blood medium, intensity of magnetic fields and the radius of the capillary. Based on two discretization techniques, finite difference method (FDM) and finite element method (FEM), the set of integrated models are transformed into a series of grid points to get a large system of equations. The third model is a single cell density model involving the three sets of first order PDEs equations for proliferating, quiescent and necrotic cells change over time and space in Cartesian coordinate which regulates under different rates of nutrients consumptions. The model presents the proliferative and quiescent cell growth depends on some parameter changes and the necrotic cells emerged as the tumor core. Some numerical schemes for solving the system of equations are compared and analyzed. Simulation and computation of the discretized model are supported by Matlab and C programming languages on a single processing unit. Some numerical results and analysis of the algorithms are presented in terms of informative presentation of tables, multiple graph and multidimensional visualization. As a conclusion, the integrated of three types mathematical modeling and the comparison of numerical performance indicates that the superior tool and analysis for solving the complete set of magnetic drug delivery system which give significant effects on the growth of the targeted cancer cell.Keywords: mathematical modeling, visualization, PDE models, magnetic nanoparticle drug delivery model, drug release model, single cell effects, avascular tumor growth, numerical analysis
Procedia PDF Downloads 428198 La0.80Ag0.15MnO3 Magnetic Nanoparticles for Self-Controlled Magnetic Fluid Hyperthermia
Authors: Marian Mihalik, Kornel Csach, Martin Kovalik, Matúš Mihalik, Martina Kubovčíková, Maria Zentková, Martin Vavra, Vladimír Girman, Jaroslav Briančin, Marija Perovic, Marija Boškovic, Magdalena Fitta, Robert Pelka
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Current nanomaterials for use in biomedicine are based mainly on iron oxides and on present knowledge on magnetic nanostructures. Manganites can represent another material which can be used optionally. Manganites and their unique electronic properties have been extensively studied in the last decades not only due to fundamental interest but to possible applications of colossal magnetoresistance, magnetocaloric effect, and ferroelectric properties. It was found that the oxygen-reduction reaction on perovskite oxide is intimately connected with metal ion e.g., orbital occupation. The effect of oxygen deviation from the stoichiometric composition on crystal structure was studied very carefully by many authors on LaMnO₃. Depending on oxygen content, the crystal structure changes from orthorhombic one to rhombohedric for oxygen content 3.1. In the case of hole-doped manganites, the change from the orthorhombic crystal structure, which is typical for La1-xCaxMnO3 based manganites, to the rhombohedric crystal structure (La1-xMxMnO₃ where M = K, Ag, and Sr based materials) results in an enormous increase of the Curie temperature. In our paper, we study the effect of oxygen content on crystal structure, thermal, and magnetic properties (including magnetocaloric effect) of La1-xAgxMnO₃nano particle system. The content of oxygen in samples was tuned by heat treatment in different thermal regimes and in various environment (air, oxygen, argon). Water nanosuspensions based on La0.80Ag0.15MnO₃ magnetic particles with the Curie temperature of about 43oC were prepared by two different approaches. First, by using a laboratory circulation mill for milling of powder in the presence of sodium dodecyl sulphate (SDS) and subsequent centrifugation. Second nanosuspension was prepared using an agate bowl, etching in citric acid and HNO3, ultrasound homogeniser, centrifugation, and dextran 40 kDA or 15 kDA as surfactant. Electrostatic stabilisation obtained by the first approach did not offer long term kinetic and aggregation colloidal stability and was unable to compensate for attractive forces between particles under a magnetic field. By the second approach, we prepared suspension oversaturated by dextran 40 kDA for steric stabilisation, with evidence of the presence of superparamagnetic behaviour. Low concentration of nanoparticles and not ideal coverage of nanoparticles impacting the stability of ferrofluids was the disadvantage of this approach. Strong steric stabilisation was observable at alcaic conditions under pH = ~10. Application of dextran 15 kDA leads to relatively stable ferrofluid with pH around physiological conditions, but desegregation of powder by HNO₃ was not effective enough, and the average size of fragments was to large of about 150 nm, and we did not see any signature of superparamagnetic behaviour. The prepared ferrofluids were characterised by scanning and transition microscope method, thermogravimetry, magnetization, and AC susceptibility measurements. Specific Absorption Rate measurements were undertaken on powder as well on ferrofluids in order to estimate the potential application of La₀.₈₀Ag₀.₁₅MnO₃ magnetic particles based ferrofluid for hyperthermia. Our complex study contains an investigation of biocompatibility and potential biohazard of this material.Keywords: manganites, magnetic nanoparticles, oxygen content, magnetic phase transition, magnetocaloric effect, ferrofluid, hyperthermia
Procedia PDF Downloads 90197 Improved Traveling Wave Method Based Fault Location Algorithm for Multi-Terminal Transmission System of Wind Farm with Grounding Transformer
Authors: Ke Zhang, Yongli Zhu
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Due to rapid load growths in today’s highly electrified societies and the requirement for green energy sources, large-scale wind farm power transmission system is constantly developing. This system is a typical multi-terminal power supply system, whose structure of the network topology of transmission lines is complex. What’s more, it locates in the complex terrain of mountains and grasslands, thus increasing the possibility of transmission line faults and finding the fault location with difficulty after the faults and resulting in an extremely serious phenomenon of abandoning the wind. In order to solve these problems, a fault location method for multi-terminal transmission line based on wind farm characteristics and improved single-ended traveling wave positioning method is proposed. Through studying the zero sequence current characteristics by using the characteristics of the grounding transformer(GT) in the existing large-scale wind farms, it is obtained that the criterion for judging the fault interval of the multi-terminal transmission line. When a ground short-circuit fault occurs, there is only zero sequence current on the path between GT and the fault point. Therefore, the interval where the fault point exists is obtained by determining the path of the zero sequence current. After determining the fault interval, The location of the short-circuit fault point is calculated by the traveling wave method. However, this article uses an improved traveling wave method. It makes the positioning accuracy more accurate by combining the single-ended traveling wave method with double-ended electrical data. What’s more, a method of calculating the traveling wave velocity is deduced according to the above improvements (it is the actual wave velocity in theory). The improvement of the traveling wave velocity calculation method further improves the positioning accuracy. Compared with the traditional positioning method, the average positioning error of this method is reduced by 30%.This method overcomes the shortcomings of the traditional method in poor fault location of wind farm transmission lines. In addition, it is more accurate than the traditional fixed wave velocity method in the calculation of the traveling wave velocity. It can calculate the wave velocity in real time according to the scene and solve the traveling wave velocity can’t be updated with the environment and real-time update. The method is verified in PSCAD/EMTDC.Keywords: grounding transformer, multi-terminal transmission line, short circuit fault location, traveling wave velocity, wind farm
Procedia PDF Downloads 263196 Study of COVID-19 Intensity Correlated with Specific Biomarkers and Environmental Factors
Authors: Satendra Pal Singh, Dalip Kr. Kakru, Jyoti Mishra, Rajesh Thakur, Tarana Sarwat
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COVID-19 is still an intrigue as far as morbidity or mortality is concerned. The rate of recovery varies from person to person, & it depends upon the accessibility of the healthcare system and the roles played by the physicians and caregivers. It is envisaged that with the passage of time, people would become immune to this virus, and those who are vulnerable would sustain themselves with the help of vaccines. The proposed study deals with the severeness of COVID-19 is associated with some specific biomarkers linked to correlate age and gender. We will be assessing the overall homeostasis of the persons who were affected by the coronavirus infection and also of those who recovered from it. Some people show more severe effects, while others show very mild symptoms, however, they show low CT values. Thus far, it is unclear why the new strain of Covid has different effects on different people in terms of age, gender, and ABO blood typing. According to data, the fatality rate with heart disease was 10.5 percent, 7.3 percent were diabetic, and 6 percent who are already infected from other comorbidities. However, some COVID-19 cases are worse than others & it is not fully explainable as of date. Overall data show that the ABO blood group is effective or prone to the risk of SARS-COV2 infection, while another study also shows the phenotypic effects of the blood group related to covid. It is an accepted fact that females have more strong immune systems than males, which may be related to the fact that females have two ‘X’ chromosomes, which might contain a more effective immunity booster gene on the X chromosome, and are capable to protect the female. Also specific sex hormones also induce a better immune response in a specific gender. This calls for in-depth analysis to be able to gain insight into this dilemma. COVID-19 is still not fully characterized, and thus we are not very familiar with its biology, mode of infection, susceptibility, and overall viral load in the human body. How many virus particles are needed to infect a person? How, then, comorbidity contribute to coronavirus infection? Since the emergence of this virus in 2020, a large number of papers have been published, and seemingly, vaccines have been prepared. But still, a large number of questions remain unanswered. The proneness of humans for infection by covid-19 needs to be established to be able to develop a better strategy to fight this virus. Our study will be on the Impact of demography on the Severity of covid-19 infection & at the same time, will look into gender-specific sensitivity of Covid-19 and the Operational variation of different biochemical markers in Covid-19 positive patients. Besides, we will be studying the co-relation, if any, of COVID severity & ABO Blood group type and the occurrence of the most common blood group type amongst positive patience.Keywords: coronavirus, ABO blood group, age, gender
Procedia PDF Downloads 98195 Simulation of Solar Assisted Absorption Cooling and Electricity Generation along with Thermal Storage
Authors: Faezeh Mosallat, Eric L. Bibeau, Tarek El Mekkawy
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Availability of a wide variety of renewable resources, such as large reserves of hydro, biomass, solar and wind in Canada provides significant potential to improve the sustainability of energy uses. As buildings represent a considerable portion of energy use in Canada, application of distributed solar energy systems for heating and cooling may increase the amount of renewable energy use. Parabolic solar trough systems have seen limited deployments in cold northern climates as they are more suitable for electricity production in southern latitudes. Heat production by concentrating solar rays using parabolic troughs can overcome the poor efficiencies of flat panels and evacuated tubes in cold climates. A numerical dynamic model is developed to simulate an installed parabolic solar trough facility in Winnipeg. The results of the numerical model are validated using the experimental data obtained from this system. The model is developed in Simulink and will be utilized to simulate a tri-generation system for heating, cooling and electricity generation in remote northern communities. The main objective of this simulation is to obtain operational data of solar troughs in cold climates as this is lacking in the literature. In this paper, the validated Simulink model is applied to simulate a solar assisted absorption cooling system along with electricity generation using organic Rankine cycle (ORC) and thermal storage. A control strategy is employed to distribute the heated oil from solar collectors among the above three systems considering the temperature requirements. This modeling provides dynamic performance results using real time minutely meteorological data which are collected at the same location the solar system is installed. This is a big step ahead of the current models by accurately calculating the available solar energy at each time step considering the solar radiation fluctuations due to passing clouds. The solar absorption cooling is modeled to use the generated heat from the solar trough system and provide cooling in summer for a greenhouse which is located next to the solar field. A natural gas water heater provides the required excess heat for the absorption cooling at low or no solar radiation periods. The results of the simulation are presented for a summer month in Winnipeg which includes the amount of generated electric power from ORC and contribution of solar energy in the cooling load provisionKeywords: absorption cooling, parabolic solar trough, remote community, validated model
Procedia PDF Downloads 216194 Modeling Standpipe Pressure Using Multivariable Regression Analysis by Combining Drilling Parameters and a Herschel-Bulkley Model
Authors: Seydou Sinde
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The aims of this paper are to formulate mathematical expressions that can be used to estimate the standpipe pressure (SPP). The developed formulas take into account the main factors that, directly or indirectly, affect the behavior of SPP values. Fluid rheology and well hydraulics are some of these essential factors. Mud Plastic viscosity, yield point, flow power, consistency index, flow rate, drillstring, and annular geometries are represented by the frictional pressure (Pf), which is one of the input independent parameters and is calculated, in this paper, using Herschel-Bulkley rheological model. Other input independent parameters include the rate of penetration (ROP), applied load or weight on the bit (WOB), bit revolutions per minute (RPM), bit torque (TRQ), and hole inclination and direction coupled in the hole curvature or dogleg (DL). The technique of repeating parameters and Buckingham PI theorem are used to reduce the number of the input independent parameters into the dimensionless revolutions per minute (RPMd), the dimensionless torque (TRQd), and the dogleg, which is already in the dimensionless form of radians. Multivariable linear and polynomial regression technique using PTC Mathcad Prime 4.0 is used to analyze and determine the exact relationships between the dependent parameter, which is SPP, and the remaining three dimensionless groups. Three models proved sufficiently satisfactory to estimate the standpipe pressure: multivariable linear regression model 1 containing three regression coefficients for vertical wells; multivariable linear regression model 2 containing four regression coefficients for deviated wells; and multivariable polynomial quadratic regression model containing six regression coefficients for both vertical and deviated wells. Although that the linear regression model 2 (with four coefficients) is relatively more complex and contains an additional term over the linear regression model 1 (with three coefficients), the former did not really add significant improvements to the later except for some minor values. Thus, the effect of the hole curvature or dogleg is insignificant and can be omitted from the input independent parameters without significant losses of accuracy. The polynomial quadratic regression model is considered the most accurate model due to its relatively higher accuracy for most of the cases. Data of nine wells from the Middle East were used to run the developed models with satisfactory results provided by all of them, even if the multivariable polynomial quadratic regression model gave the best and most accurate results. Development of these models is useful not only to monitor and predict, with accuracy, the values of SPP but also to early control and check for the integrity of the well hydraulics as well as to take the corrective actions should any unexpected problems appear, such as pipe washouts, jet plugging, excessive mud losses, fluid gains, kicks, etc.Keywords: standpipe, pressure, hydraulics, nondimensionalization, parameters, regression
Procedia PDF Downloads 84193 Formulation and Characterization of Active Edible Films from Cassava Starch for Snacks and Savories
Authors: P. Raajeswari, S. M. Devatha, S. Yuvajanani, U. Rashika
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Edible food packaging are the need of the hour to save life on land and under water by eliminating waste cycle and replacing Single Use Plastics at grass root level as it can be eaten or composted as such. Cassava (Manihot esculenta) selected for making edible films are rich source of starch, and also it exhibit good sheeting propertiesdue to the high amylose: amylopectin content. Cassava starch was extracted by manual method at a laboratory scale and yielded 65 per cent. Edible films were developed by adding food grade plasticizers and water. Glycerol showed good plasticizing property as compared to sorbitol and polylactic acid in both manual (petri dish) and machine (film making machine) production. The thickness of the film is 0.25±0.03 mm. Essential oil and components from peels like pomegranate, orange, pumpkin, onion, and banana brat, and herbs like tulsi and country borage was extracted through the standardized aqueous and alkaline method. In the standardized film, the essential oil and components from selected peel and herbs were added to the casting solution separately and casted the film. It was added to improve the anti-oxidant, anti-microbial and optical properties. By inclusion of extracts, it reduced the bubble formation while casting. FTIR, Water Vapor and Oxygen Transmission Rate (WVTR and OTR), tensile strength, microbial load, shelf life, and degradability of the films were done to analyse the mechanical property of the standardized films. FTIR showed the presence of essential oil. WVTR and OTR of the film was improved after inclusion of essential oil and extracts from 1.312 to 0.811 cm₃/m₂ and 15.12 to 17.81 g/ m₂.d. Inclusion of essential oil from herbs showed better WVTR and OTR than the inclusion of peel extract and standard. Tensile strength and Elongation at break has not changed by essential oil and extracts at 0.86 ± 0.12 mpa and 14 ± 2 at 85 N force. By inclusion of extracts, an optical property of the film enhanced, and it increases the appearance of the packaging material. The films were completely degraded on 84thdays and partially soluble in water. Inclusion of essential oil does not have impact on degradability and solubility. The microbial loads of the active films were decreased from 15 cfu/gm to 7 cfu/gm. The films can be stored at frozen state for 24 days and 48 days at atmospheric temperature when packed with South Indian snacks and savories.Keywords: active films, cassava starch, plasticizer, characterization
Procedia PDF Downloads 81192 Ergonomic Assessment of Workplace Environment of Flour Mill Workers
Authors: Jayshree P. Zend, Ashatai B. Pawar
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The study was carried out in Parbhani district of Maharashtra state, India with the objectives to study environmental problems faced by flour mill workers, prevalence of work-related health hazards and the physiological cost of workers while performing work in flour mill in traditional method as well as improved method. The use of flour presser, dust controlling bag and noise and dust controlling mask developed by AICRP College of Home Science, VNMKV, Parbhani was considered as an improved method. This investigation consisted survey and experiment which was conducted in the respective locations of flour mills. Healthy, non-smoking 30 flour mill workers ranged between the age group of 20-50 yrs comprising 16 female and 14 male working at flour mill for 4-8 hrs/ day and 6 days/ week and had minimum five years experience of work in flour mill were selected for the study. Pulmonary function test of flour mill workers was carried out by trained technician at Dr. ShankarraoChavan Government Medical College, Nanded by using Electronic Spirometer. The data regarding heart rate (resting, working and recovery), energy expenditure, musculoskeletal problems and occupational health hazards and accidents were recorded by using pretested questionnaire. Scientific equipment used in the experiment were polar sport test heart rate monitor, Hygrometer, Goniometer, Dialed Thermometer, Sound Level Meter, Lux Meter, Ambient Air Sampler and Air Quality Monitor. The collected data were subjected to appropriate statistical analysis such as 't' test and correlation coefficient test. Results indicated that improved method i.e. use of noise and dust controlling mask, flour presser and dust controlling bag were effective in reducing physiological cost of work of flour mill workers. Lung function test of flour mill workers showed decreased values of all parameters, hence the results of present study support paying attention to use of personal protective noise and dust controlling mask by flour mill workers and also to the working conditions in flour mill especially ventilation and illumination level needs to be enhanced in flour mill. The study also emphasizes the need to develop some mechanism for lifting load of grains and unloading in the hopper. It is also suggested that the flour mill workers should use flour presser suitable to their height to avoid frequent bending and should use dust controlling bag to flour outlet of machine to reduce inhalable flour dust level in the flour mill.Keywords: physiological cost, energy expenditure, musculoskeletal problems
Procedia PDF Downloads 401191 The Rehabilitation of The Covered Bridge Leclerc (P-00249) Passing Over the Bouchard Stream in LaSarre, Quebec
Authors: Nairy Kechichian
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The original Leclerc Bridge is a covered wooden bridge that is considered a Quebec heritage structure with an index of 60, making it a very important provincial bridge from a historical point of view. It was constructed in 1927 and is in the rural area of Abitibi-Temiscamingue. It is a “town Québécois” type of structure, which is generally rare but common for covered bridges in Abitibi-Temiscamingue. This type of structure is composed of two trusses on both sides formed with diagonals, internal bracings, uprights and top and bottom chords to allow the transmission of loads. This structure is mostly known for its solidity, lightweightness, and ease of construction. It is a single-span bridge with a length of 25.3 meters and allows the passage of one vehicle at a time with a 4.22-meter driving lane. The structure is composed of 2 trusses located at each end of the deck, two gabion foundations at both ends, uprights and top and bottom chords. WSP (Williams Sale Partnership) Canada inc. was mandated by the Transport Minister of Quebec in 2019 to increase the capacity of the bridge from 5 tons to 30.6 tons and rehabilitate it, as it has deteriorated quite significantly over the years. The bridge was damaged due to material deterioration over time, exposure to humidity, high load effects and insect infestation. To allow the passage of 3 axle trucks, as well as to keep the integrity of this heritage structure, the final design chosen to rehabilitate the bridge involved adding a new deck independent from the roof structure of the bridge. Essentially, new steel beams support the deck loads and the desired vehicle loads. The roof of the bridge is linked to the steel deck for lateral support, but it is isolated from the wooden deck. The roof is preserved for aesthetic reasons and remains intact as it is a heritage piece. Due to strict traffic management obstacles, an efficient construction method was put into place, which consisted of building a temporary bridge and moving the existing roof onto it to allow the circulation of vehicles on one side of the temporary bridge while providing a working space for the repairs of the roof on the other side to take place simultaneously. In parallel, this method allowed the demolition and reconstruction of the existing foundation, building a new steel deck, and transporting back the roof on the new bridge. One of the main criteria for the rehabilitation of the wooden bridge was to preserve, as much as possible, the existing patrimonial architectural design of the bridge. The project was completed successfully by the end of 2021.Keywords: covered bridge, wood-steel, short span, town Québécois structure
Procedia PDF Downloads 67190 The Shrinking of the Pink Wave and the Rise of the Right-Wing in Latin America
Authors: B. M. Moda, L. F. Secco
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Through free and fair elections and others less democratic processes, Latin America has been gradually turning into a right-wing political region. In order to understand these recent changes, this paper aims to discuss the origin and the traits of the pink wave in the subcontinent, the reasons for its current rollback and future projections for left-wing in the region. The methodology used in this paper will be descriptive and analytical combined with secondary sources mainly from the social and political sciences fields. The canons of the Washington Consensus was implemented by the majority of the Latin American governments in the 80s and 90s under the social democratic and right-wing parties. The neoliberal agenda caused political, social and economic dissatisfaction bursting into a new political configuration for the region. It started in 1998 when Hugo Chávez took the office in Venezuela through the Fifth Republic Movement under the socialist flag. From there on, Latin America was swiped by the so-called ‘pink wave’, term adopted to define the rising of self-designated left-wing or center-left parties with a progressive agenda. After Venezuela, countries like Chile, Brazil, Argentina, Uruguay, Bolivia, Equator, Nicaragua, Paraguay, El Salvador and Peru got into the pink wave. The success of these governments was due a post-neoliberal agenda focused on cash transfers programs, increasing of public spending, and the straightening of national market. The discontinuation of the preference for the left-wing started in 2012 with the coup against Fernando Lugo in Paraguay. In 2015, the chavismo in Venezuela lost the majority of the legislative seats. In 2016, an impeachment removed the Brazilian president Dilma Rousself from office who was replaced by the center-right vice-president Michel Temer. In the same year, Mauricio Macri representing the right-wing party Proposta Republicana was elected in Argentina. In 2016 center-right and liberal, Pedro Pablo Kuczynski was elected in Peru. In 2017, Sebastián Piñera was elected in Chile through the center-right party Renovación Nacional. The pink wave current rollback points towards some findings that can be arranged in two fields. Economically, the 2008 financial crisis affected the majority of the Latin American countries and the left-wing economic policies along with the end of the raw materials boom and the subsequent shrinking of economic performance opened a flank for popular dissatisfaction. In Venezuela, the 2014 oil crisis reduced the revenues for the State in more than 50% dropping social spending, creating an inflationary spiral, and consequently loss of popular support. Politically, the death of Hugo Chavez in 2013 weakened the ‘socialism of the twenty first century’ ideal, which was followed by the death of Fidel Castro, the last bastion of communism in the subcontinent. In addition, several cases of corruption revealed during the pink wave governments made the traditional politics unpopular. These issues challenge the left-wing to develop a future agenda based on innovation of its economic program, improve its legal and political compliance practices, and to regroup its electoral forces amid the social movements that supported its ascension back in the early 2000s.Keywords: Latin America, political parties, left-wing, right-wing, pink wave
Procedia PDF Downloads 240189 Multilevel of Factors Affected Optimal Adherence to Antiretroviral Therapy and Viral Suppression amongst HIV-Infected Prisoners in South Ethiopia: A Prospective Cohort Study
Authors: Terefe Fuge, George Tsourtos , Emma Miller
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Objectives: Maintaining optimal adherence and viral suppression in people living with HIV (PLWHA) is essential to ensure both preventative and therapeutic benefits of antiretroviral therapy (ART). Prisoners bear a particularly high burden of HIV infection and are highly likely to transmit to others during and after incarceration. However, the level of adherence and viral suppression, as well as its associated factors in incarcerated populations in low-income countries is unknown. This study aimed to determine the prevalence of non-adherence and viral failure, and contributing factors to this amongst prisoners in South Ethiopia. Methods: A prospective cohort study was conducted between June 1, 2019 and July 31, 2020 to compare the level of adherence and viral suppression between incarcerated and non-incarcerated PLWHA. The study involved 74 inmates living with HIV (ILWHA) and 296 non-incarcerated PLWHA. Background information including sociodemographic, socioeconomic, psychosocial, behavioural, and incarceration-related characteristics was collected using a structured questionnaire. Adherence was determined based on participants’ self-report and pharmacy refill records, and plasma viral load measurements which were undertaken within the study period were prospectively extracted to determine viral suppression. Various univariate and multivariate regression models were used to analyse data. Results: Self-reported dose adherence was approximately similar between ILWHA and non-incarcerated PLWHA (81% and 83% respectively), but ILWHA had a significantly higher medication possession ratio (MPR) (89% vs 75%). The prevalence of viral failure (VF) was slightly higher (6%) in ILWHA compared to non-incarcerated PLWHA (4.4%). The overall dose non-adherence (NA) was significantly associated with missing ART appointments, level of satisfaction with ART services, patient’s ability to comply with a specified medication schedule and types of methods used to monitor the schedule. In ILWHA specifically, accessing ART services from a hospital compared to a health centre, an inability to always attend clinic appointments, experience of depression and a lack of social support predicted NA. VF was significantly higher in males, people of age 31-35 years and in those who experienced social stigma, regardless of their incarceration status. Conclusions: This study revealed that HIV-infected prisoners in South Ethiopia were more likely to be non-adherent to doses and so to develop viral failure compared to their non-incarcerated counterparts. A multitude of factors was found to be responsible for this requiring multilevel intervention strategies focusing on the specific needs of prisoners.Keywords: Adherence , Antiretroviral therapy, Incarceration, South Ethiopia, Viral suppression
Procedia PDF Downloads 135188 Application of Principal Component Analysis and Ordered Logit Model in Diabetic Kidney Disease Progression in People with Type 2 Diabetes
Authors: Mequanent Wale Mekonen, Edoardo Otranto, Angela Alibrandi
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Diabetic kidney disease is one of the main microvascular complications caused by diabetes. Several clinical and biochemical variables are reported to be associated with diabetic kidney disease in people with type 2 diabetes. However, their interrelations could distort the effect estimation of these variables for the disease's progression. The objective of the study is to determine how the biochemical and clinical variables in people with type 2 diabetes are interrelated with each other and their effects on kidney disease progression through advanced statistical methods. First, principal component analysis was used to explore how the biochemical and clinical variables intercorrelate with each other, which helped us reduce a set of correlated biochemical variables to a smaller number of uncorrelated variables. Then, ordered logit regression models (cumulative, stage, and adjacent) were employed to assess the effect of biochemical and clinical variables on the order-level response variable (progression of kidney function) by considering the proportionality assumption for more robust effect estimation. This retrospective cross-sectional study retrieved data from a type 2 diabetic cohort in a polyclinic hospital at the University of Messina, Italy. The principal component analysis yielded three uncorrelated components. These are principal component 1, with negative loading of glycosylated haemoglobin, glycemia, and creatinine; principal component 2, with negative loading of total cholesterol and low-density lipoprotein; and principal component 3, with negative loading of high-density lipoprotein and a positive load of triglycerides. The ordered logit models (cumulative, stage, and adjacent) showed that the first component (glycosylated haemoglobin, glycemia, and creatinine) had a significant effect on the progression of kidney disease. For instance, the cumulative odds model indicated that the first principal component (linear combination of glycosylated haemoglobin, glycemia, and creatinine) had a strong and significant effect on the progression of kidney disease, with an effect or odds ratio of 0.423 (P value = 0.000). However, this effect was inconsistent across levels of kidney disease because the first principal component did not meet the proportionality assumption. To address the proportionality problem and provide robust effect estimates, alternative ordered logit models, such as the partial cumulative odds model, the partial adjacent category model, and the partial continuation ratio model, were used. These models suggested that clinical variables such as age, sex, body mass index, medication (metformin), and biochemical variables such as glycosylated haemoglobin, glycemia, and creatinine have a significant effect on the progression of kidney disease.Keywords: diabetic kidney disease, ordered logit model, principal component analysis, type 2 diabetes
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