Search results for: supply chain flexibility
2626 X-Ray Detector Technology Optimization in Computed Tomography
Authors: Aziz Ikhlef
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Most of multi-slices Computed Tomography (CT) scanners are built with detectors composed of scintillator - photodiodes arrays. The photodiodes arrays are mainly based on front-illuminated technology for detectors under 64 slices and on back-illuminated photodiode for systems of 64 slices or more. The designs based on back-illuminated photodiodes were being investigated for CT machines to overcome the challenge of the higher number of runs and connection required in front-illuminated diodes. In backlit diodes, the electronic noise has already been improved because of the reduction of the load capacitance due to the routing reduction. This is translated by a better image quality in low signal application, improving low dose imaging in large patient population. With the fast development of multi-detector-rows CT (MDCT) scanners and the increasing number of examinations, the clinical community has raised significant concerns on radiation dose received by the patient in both medical and regulatory community. In order to reduce individual exposure and in response to the recommendations of the International Commission on Radiological Protection (ICRP) which suggests that all exposures should be kept as low as reasonably achievable (ALARA), every manufacturer is trying to implement strategies and solutions to optimize dose efficiency and image quality based on x-ray emission and scanning parameters. The added demands on the CT detector performance also comes from the increased utilization of spectral CT or dual-energy CT in which projection data of two different tube potentials are collected. One of the approaches utilizes a technology called fast-kVp switching in which the tube voltage is switched between 80 kVp and 140 kVp in fraction of a millisecond. To reduce the cross-contamination of signals, the scintillator based detector temporal response has to be extremely fast to minimize the residual signal from previous samples. In addition, this paper will present an overview of detector technologies and image chain improvement which have been investigated in the last few years to improve the signal-noise ratio and the dose efficiency CT scanners in regular examinations and in energy discrimination techniques. Several parameters of the image chain in general and in the detector technology contribute in the optimization of the final image quality. We will go through the properties of the post-patient collimation to improve the scatter-to-primary ratio, the scintillator material properties such as light output, afterglow, primary speed, crosstalk to improve the spectral imaging, the photodiode design characteristics and the data acquisition system (DAS) to optimize for crosstalk, noise and temporal/spatial resolution.Keywords: computed tomography, X-ray detector, medical imaging, image quality, artifacts
Procedia PDF Downloads 1942625 Systems Strengthening for Sustainable Family Planning Service Provision in Uganda
Authors: D. Muyama, M. Luyiga, P. Buyungo, D. Chemonges, M. Namukwaya, L. Ssekabembe, B. Lukwago, D. Kyamagwa
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Context: The study focuses on the sustainability of health interventions in Uganda, particularly in the private sector, beyond donor-funded project periods. The Population Services International (PSI) implemented the Women Health Project (WHP) to ensure continued access to quality family planning, cervical cancer screening, and post-abortion care services through private clinics. Research Aim: The aim of the study is to assess the continued access to quality family planning, cervical cancer screening, and post-abortion care services through the private sector after the closure or reduction in funding of the WHP. Methodology: PSI trained and mentored 83 clinics to establish functional systems in self-regulatory quality improvement, supply chain, referral, and demand creation. The clinics were also connected to the national reporting system and utilized Ministry of Health reporting tools. An assessment tool with six criteria was designed and used to evaluate the progress of the clinics. Clinics scoring 75% and above were considered independent and graduated from the program. Findings: Out of the 83 private clinics, 56 successfully met the graduation criteria and graduated from the program, while 25 lost interest and were gradually dropped. Two clinics failed to achieve the criteria due to leadership challenges. The 59 graduating clinics continued to provide high-quality family planning services, including IUD, implant, Depo-Provera, oral contraceptives, and post-abortion care. All graduating clinics were reassessed and found to still be capable of offering services, attributing their success to government stock availability and acquired skills through mentorships. The clinics expressed appreciation to PSI for the sustainable plan that allowed them to operate beyond the project period. Theoretical Importance: This study contributes to the understanding of sustainability planning and the importance of clinic owners' attitudes and buy-in for continued service provision. It emphasizes the implementation of sustainability plans through existing structures to leverage available resources and ensure continuity of care. Data Collection and Analysis Procedures: The study collected data through the assessment tool that evaluated the progress of clinics based on the established criteria. The tool was scored out of 100%, and clinics scoring above 75% were deemed independent. The findings were analyzed quantitatively to determine the success rate of clinics in meeting the graduation criteria. Questions Addressed: The study addresses the question of whether private clinics in Uganda can sustain the provision of family planning, cervical cancer screening, and post-abortion care services after the closure or reduction in funding of the WHP. Conclusion: The study concludes that the attitude and buy-in of clinic owners are essential for sustainability planning. Implementing sustainability plans through existing structures and leveraging available resources are crucial for the continuity of care after the end of a project or reduced funding. The findings highlight the importance of establishing sustainable plans to ensure continued access to essential health services beyond the project period. Contributions: This study contributes to the existing knowledge for programmers implementing or intending to implement donor-funded projects. It provides insights into designing sustainable plans that enable the independent operation of clinics even after the end of a project.Keywords: graduation, family planning, systems strengthening, sustainability
Procedia PDF Downloads 662624 Development of EREC IF Model to Increase Critical Thinking and Creativity Skills of Undergraduate Nursing Students
Authors: Kamolrat Turner, Boontuan Wattanakul
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Critical thinking and creativity are prerequisite skills for working professionals in the 21st century. A survey conducted in 2014 at the Boromarajonani College of Nursing, Chon Buri, Thailand, revealed that these skills within students across all academic years was at a low to moderate level. An action research study was conducted to develop the EREC IF Model, a framework which includes the concepts of experience, reflection, engagement, culture and language, ICT, and flexibility and fun, to guide pedagogic activities for 75 sophomores of the undergraduate nursing science program at the college. The model was applied to all professional nursing courses. Prior to implementation, workshops were held to prepare lecturers and students. Both lecturers and students initially expressed their discomfort and pointed to the difficulties with the model. However, later they felt more comfortable, and by the end of the project they expressed their understanding and appreciation of the model. A survey conducted four and eight months after implementation found that the critical thinking and creativity skills of the sophomores were significantly higher than those recorded in the pretest. It could be concluded that the EREC IF model is efficient for fostering critical thinking and creativity skills in the undergraduate nursing science program. This model should be used for other levels of students.Keywords: critical thinking, creativity, undergraduate nursing students, EREC IF model
Procedia PDF Downloads 3222623 Isolation and Characterization of Collagen from Chicken Feet
Authors: P. Hashim, M. S. Mohd Ridzwan, J. Bakar
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Collagen was isolated from chicken feet by using papain and pepsin enzymes in acetic acid solution at 4°C for 24h with a yield of 18.16% and 22.94% by dry weight, respectively. Chemical composition and characteristics of chicken feet collagen such as amino acid composition, SDS-PAGE patterns, FTIR spectra and thermal properties were evaluated. The chicken feet collagen is rich in the amino acids glycine, glutamic acid, proline and hydroxyproline. Electrophoresis pattern demonstrated two distinct α-chains (α1 and α2) and β chain, indicating that type I collagen is a major component of chicken feet collagen. The thermal stability of collagen isolated by papain and pepsin revealed stable denaturation temperatures of 48.40 and 53.35°C, respectively. The FTIR spectra of both collagens were similar with amide regions in A, B, I, II, and III. The study demonstrated that chicken feet collagen using papain isolation method is possible as commercial alternative ingredient.Keywords: chicken feet, collagen, papain, pepsin
Procedia PDF Downloads 4282622 Application of Universal Distribution Factors for Real-Time Complex Power Flow Calculation
Authors: Abdullah M. Alodhaiani, Yasir A. Alturki, Mohamed A. Elkady
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Complex power flow distribution factors, which relate line complex power flows to the bus injected complex powers, have been widely used in various power system planning and analysis studies. In particular, AC distribution factors have been used extensively in the recent power and energy pricing studies in free electricity market field. As was demonstrated in the existing literature, many of the electricity market related costing studies rely on the use of the distribution factors. These known distribution factors, whether the injection shift factors (ISF’s) or power transfer distribution factors (PTDF’s), are linear approximations of the first order sensitivities of the active power flows with respect to various variables. This paper presents a novel model for evaluating the universal distribution factors (UDF’s), which are appropriate for an extensive range of power systems analysis and free electricity market studies. These distribution factors are used for the calculations of lines complex power flows and its independent of bus power injections, they are compact matrix-form expressions with total flexibility in determining the position on the line at which line flows are measured. The proposed approach was tested on IEEE 9-Bus system. Numerical results demonstrate that the proposed approach is very accurate compared with exact method.Keywords: distribution factors, power system, sensitivity factors, electricity market
Procedia PDF Downloads 4732621 Heading for Modern Construction Management: Recommendation for Employers
Authors: Robin Becker, Maike Eilers, Nane Roetmann, Manfred Helmus
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The shortage of junior staff in the construction industry is a problem that will be further exacerbated in the coming years by the retirement of the baby-boom generations (1955-1969) from employment. In addition, the current working conditions in the field of construction management are not attractive for young professionals. A survey of students revealed a desire for an increase in flexibility and an improved work-life balance in everyday working life. Students of civil engineering and architecture are basically interested in a career in construction management but have reservations due to the image of the profession and the current working conditions. A survey among experts from the construction industry shows that the profession can become more attractive. This report provides recommendations for action in the form of working modules to improve the working conditions of employees. If these are taken into account, graduates can be attracted to the profession of construction management, and existing staff can be retained more effectively. The aim of this report is to show incentives for employers to respond to the wishes and needs of their current and future employees to the extent that can be implemented.Keywords: modern construction management, construction industry, work modules, shortage of junior staff, sustainable personnel management, making construction management more attractive, working time model
Procedia PDF Downloads 832620 ATR-IR Study of the Mechanism of Aluminum Chloride Induced Alzheimer Disease - Curative and Protective Effect of Lepidium sativum Water Extract on Hippocampus Rats Brain Tissue
Authors: Maha J. Balgoon, Gehan A. Raouf, Safaa Y. Qusti, Soad S. Ali
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The main cause of Alzheimer disease (AD) was believed to be mainly due to the accumulation of free radicals owing to oxidative stress (OS) in brain tissue. The mechanism of the neurotoxicity of Aluminum chloride (AlCl3) induced AD in hippocampus Albino wister rat brain tissue, the curative & the protective effects of Lipidium sativum group (LS) water extract were assessed after 8 weeks by attenuated total reflection spectroscopy ATR-IR and histologically by light microscope. ATR-IR results revealed that the membrane phospholipid undergo free radical attacks, mediated by AlCl3, primary affects the polyunsaturated fatty acids indicated by the increased of the olefinic -C=CH sub-band area around 3012 cm-1 from the curve fitting analysis. The narrowing in the half band width(HBW) of the sνCH2 sub-band around 2852 cm-1 due to Al intoxication indicates the presence of trans form fatty acids rather than gauch rotomer. The degradation of hydrocarbon chain to shorter chain length, increasing in membrane fluidity, disorder and decreasing in lipid polarity in AlCl3 group were indicated by the detected changes in certain calculated area ratios compared to the control. Administration of LS was greatly improved these parameters compared to the AlCl3 group. Al influences the Aβ aggregation and plaque formation, which in turn interferes to and disrupts the membrane structure. The results also showed a marked increase in the β-parallel and antiparallel structure, that characterize the Aβ formation in Al-induced AD hippocampal brain tissue, indicated by the detected increase in both amide I sub-bands around 1674, 1692 cm-1. This drastic increase in Aβ formation was greatly reduced in the curative and protective groups compared to the AlCl3 group and approaches nearly the control values. These results were supported too by the light microscope. AlCl3 group showed significant marked degenerative changes in hippocampal neurons. Most cells appeared small, shrieked and deformed. Interestingly, the administration of LS in curative and protective groups markedly decreases the amount of degenerated cells compared to the non-treated group. Also the intensity of congo red stained cells was decreased. Hippocampal neurons looked more/or less similar to those of control. This study showed a promising therapeutic effect of Lipidium sativum group (LS) on AD rat model that seriously overcome the signs of oxidative stress on membrane lipid and restore the protein misfolding.Keywords: aluminum chloride, alzheimer disease, ATR-IR, Lipidium sativum
Procedia PDF Downloads 3662619 Gas Lift Optimization Using Smart Gas Lift Valve
Authors: Mohamed A. G. H. Abdalsadig, Amir Nourian, G. G. Nasr, M. Babaie
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Gas lift is one of the most common forms of artificial lift, particularly for offshore wells because of its relative down hole simplicity, flexibility, reliability, and ability to operate over a large range of rates and occupy very little space at the well head. Presently, petroleum industry is investing in exploration and development fields in offshore locations where oil and gas wells are being drilled thousands of feet below the ocean in high pressure and temperature conditions. Therefore, gas-lifted oil wells are capable of failure through gas lift valves which are considered as the heart of the gas lift system for controlling the amount of the gas inside the tubing string. The gas injection rate through gas lift valve must be controlled to be sufficient to obtain and maintain critical flow, also, gas lift valves must be designed not only to allow gas passage through it and prevent oil passage, but also for gas injection into wells to be started and stopped when needed. In this paper, smart gas lift valve has been used to investigate the effect of the valve port size, depth of injection and vertical lift performance on well productivity; all these aspects have been investigated using PROSPER simulator program coupled with experimental data. The results show that by using smart gas lift valve, the gas injection rate can be controlled which leads to improved flow performance.Keywords: Effect of gas lift valve port size, effect water cut, vertical flow performance
Procedia PDF Downloads 2912618 A Lifeline Vulnerability Study of Constantine, Algeria
Authors: Mounir Ait Belkacem, Mehdi Boukri, Omar Amellal, Nacim Yousfi, Abderrahmane Kibboua, Med Naboussi Farsi, Mounir Naili
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The North of Algeria is located in a seismic zone, then earthquakes are probably the most likely natural disaster that would lead to major lifeline disruption. The adequate operation of lifelines is vital for the economic development of regions under moderate to high seismic activity. After an earthquake, the proper operation of all vital systems is necessary, for instance hospitals for medical attention of the wounded and highways for communication and assistance for victims.In this work we apply the knowledge of pipeline vulnerability to the water supply system, sanitary sewer pipelines (waste water), and telephone in Constantine (Algeria).Keywords: lifeline, earthquake, vulnerability, pipelines
Procedia PDF Downloads 5642617 Design of Mobile Teaching for Students Collaborative Learning in Distance Higher Education
Authors: Lisbeth Amhag
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The aim of the study is to describe and analyze the design of mobile teaching for students collaborative learning in distance higher education with a focus on mobile technologies as online webinars (web-based seminars or conferencing) by using laptops, smart phones, or tablets. These multimedia tools can provide face-to-face interactions, recorded flipped classroom videos and parallel chat communications. The data collection consists of interviews with 22 students and observations of online face-to-face webinars, as well two surveys. Theoretically, the study joins the research tradition of Computer Supported Collaborative learning, CSCL, as well as Computer Self-Efficacy, CSE concerned with individuals’ media and information literacy. Important conclusions from the study demonstrated mobile interactions increased student centered learning. As the students were appreciating the working methods, they became more engaged and motivated. The mobile technology using among student also contributes to increased flexibility between space and place, as well as media and information literacy.Keywords: computer self-efficacy, computer supported collaborative learning, distance and open learning, educational design and technologies, media and information literacy, mobile learning
Procedia PDF Downloads 3582616 Characterization of Enhanced Thermostable Polyhydroxyalkanoates
Authors: Ahmad Idi
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The biosynthesis and properties of polyhydroxyalkanoate (PHA) are determined by the bacterial strain and the culture condition. Hence this study elucidates the structure and properties of PHA produced by a newly isolated strain of photosynthetic bacterium, Rhodobacter sphaeroides ADZ101 grown under the optimized culture condition. The properties of the accumulated PHA were determined via FTIR, NMR, TGA, and GCMS analyses. The results showed that acetate and ammonia chloride had the highest PHA accumulation with a ratio of 32.5 mM at neutral pH. The structural analyses showed that the polymer comprises both short and medium-chain length monomers ranging from C5, C13, C14, and C18, as well as the presence of novel PHA monomers. The thermal analysis revealed that the maximum temperature of decomposition occurred at 395°C and 454°C, indicating two major decomposition reactions. Thus this bacterial strain, optimized culture condition, and the abundance of novel monomers enhanced the thermostability of the accumulated PHA.Keywords: bioplastic polyhydroxyalkanoates Rhodobacter sphaeroides ADZ101 thermostable PHA
Procedia PDF Downloads 1452615 A Thermosensitive Polypeptide Hydrogel for Biomedical Application
Authors: Chih-Chi Cheng, Ji-Yu Lin, I-Ming Chu
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In this study, we synthesized a thermosensitive polypeptide hydrogel by copolymerizing poloxamer (PLX) and poly(ʟ-alanine) with ʟ-lysine segments at the both ends to form PLX-b-poly(ʟ-alanine-lysine) (Lys-Ala-PLX-Ala-Lys) copolymers. Poly(ʟ-alanine) is the hydrophobic chain of Lys-Ala-PLX-Ala-Lys copolymers which was designed to capture the hydrophobic agents. The synthesis was examined by 1H NMR and showed that Lys-Ala-PLX-Ala-Lys copolymers were successfully synthesized. At the concentration range of 3-7 wt%, the aqueous copolymer solution underwent sol-gel transition near the physiological temperature and exhibited changes in its secondary structure content, as evidenced by FTIR. The excellent viability of cells cultured within the scaffold was observed after 72 hr of incubation. Also, negatively charged bovine serum albumin was incorporated into the hydrogel without diminishing material integrity and shows good release profile. In the animal study, the results also indicated that Lys-Ala-PLX-Ala-Lys hydrogel has high potential in wound dressing.Keywords: polypeptide thermosensitive hydrogel, tacrolimus, vascularized composite allotransplantation, sustain release
Procedia PDF Downloads 2912614 Switched Ultracapacitors for Maximizing Energy Supply
Authors: Nassouh K. Jaber
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Supercapacitors (S.C.) are presently attracting attention for driving general purpose (12VDC to 220VAC) inverters in renewable energy systems. Unfortunately, when the voltage of the S.C supplying the inverter reaches the minimal threshold of 7-8VDC the inverter shuts down leaving the remaining 40% of the valuable energy stored inside the ultracapacitor un-usable. In this work a power electronic circuit is proposed which switches 2 banks of supercapacitors from parallel connection when both are fully charged at 14VDC to serial connection when their voltages drop down to 7 volts, thus keeping the inverter working within its operating limits for a longer time and advantageously tapping almost 92% of the stored energy in the supercapacitors.Keywords: ultra capacitor, switched ultracapacitors, inverter, supercapacitor, parallel connection, serial connection, battery limitation
Procedia PDF Downloads 4112613 Realization of a (GIS) for Drilling (DWS) through the Adrar Region
Authors: Djelloul Benatiallah, Ali Benatiallah, Abdelkader Harouz
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Geographic Information Systems (GIS) include various methods and computer techniques to model, capture digitally, store, manage, view and analyze. Geographic information systems have the characteristic to appeal to many scientific and technical field, and many methods. In this article we will present a complete and operational geographic information system, following the theoretical principles of data management and adapting to spatial data, especially data concerning the monitoring of drinking water supply wells (DWS) Adrar region. The expected results of this system are firstly an offer consulting standard features, updating and editing beneficiaries and geographical data, on the other hand, provides specific functionality contractors entered data, calculations parameterized and statistics.Keywords: GIS, DWS, drilling, Adrar
Procedia PDF Downloads 3092612 Physicochemical Properties of Palm Stearin (PS) and Palm Kernel Olein (PKOO) Blends as Potential Edible Coating Materials
Authors: I. Ruzaina, A. B. Rashid, M. S. Halimahton Zahrah, C. S. Cheow, M. S. Adi
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This study was conducted to determine the potential of palm stearin (PS) as edible coating materials for fruits. The palm stearin was blended with 20-80% palm kernel olein (PKOo) and the properties of the blends were evaluated in terms of the slip melting point (SMP), solid fat content (SFC), fatty acid and triacylglycerol compositions (TAG), and polymorphism. Blending of PS with PKOo reduced the SMP, SFC, altered the FAC and TAG composition and changed the crystal polymorphism from β to mixture of β and β′. The changes in the physicochemical properties of PS were due to the replacement of the high melting TAG in PS with medium chain TAG in PKOo. From the analysis, 1:1 and 3:2 were the better PSPKOo blend formulations in slowing down the weight loss, respiration gases and gave better appearance when compared to other PSPKOo blends formulations.Keywords: guava, palm stearin, palm kernel olein, physicochemical
Procedia PDF Downloads 5842611 Modelling High-Frequency Crude Oil Dynamics Using Affine and Non-Affine Jump-Diffusion Models
Authors: Katja Ignatieva, Patrick Wong
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We investigated the dynamics of high frequency energy prices, including crude oil and electricity prices. The returns of underlying quantities are modelled using various parametric models such as stochastic framework with jumps and stochastic volatility (SVCJ) as well as non-parametric alternatives, which are purely data driven and do not require specification of the drift or the diffusion coefficient function. Using different statistical criteria, we investigate the performance of considered parametric and nonparametric models in their ability to forecast price series and volatilities. Our models incorporate possible seasonalities in the underlying dynamics and utilise advanced estimation techniques for the dynamics of energy prices.Keywords: stochastic volatility, affine jump-diffusion models, high frequency data, model specification, markov chain monte carlo
Procedia PDF Downloads 1042610 Optimal Decisions for Personalized Products with Demand Information Updating and Limited Capacity
Authors: Meimei Zheng
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Product personalization could not only bring new profits to companies but also provide the direction of long-term development for companies. However, the characteristics of personalized product cause some new problems. This paper investigates how companies make decisions on the supply of personalized products when facing different customer attitudes to personalized product and service, constraints due to limited capacity and updates of personalized demand information. This study will provide optimal decisions for companies to develop personalized markets, resulting in promoting business transformation and improving business competitiveness.Keywords: demand forecast updating, limited capacity, personalized products, optimization
Procedia PDF Downloads 2622609 Toward an Integrated Safe and Sustainable Food System: A General Overview
Authors: Erkan Rehber, Hasan Vural, Sule Turhan
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It is a fact that food is a vital need of human beings. As a consumer, everyone has the right to access adequate and safe food. There are considerable development to establish quality standards and schemes to have safe foods and sustainable agriculture alternatives to protect natural resources and environment to reach this target. Recently, there is also a remarkable development in integration and combination of these efforts. Food Safety and Sustainable Agriculture Forum organized in 2014, Beijing shows that it is a global awareness more than being an individual view. Eventually, quality standards, assurance systems applied to conventional agriculture has to be applied to sustainable agriculture alternatives to have a holistic sustainable food chain from seed to fork. All actors of the whole food system from farmer to ultimate consumers, along with the state, have to work together meeting this big challenge.Keywords: integrated safe, food safety, sustainable food system, consumer
Procedia PDF Downloads 5612608 Introduction of PMMA-Tag to VHH for Improving Recovery and Immobilization Rate of VHHS
Authors: Bongmun Kang, Kagnari Yamakawa, Yoshihisa Hagihara, Yuji Ito, Michimasa Kishimoto, Yoichi Kumada
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The PMMA-tag was genetically fused with the C-terminal region of VHH molecules. This antibody, VHH, is known as a single-chain domain, which is devoid of light chains. The PMMA-tag, which could affect the isoelectric point (pI) changeable with a charge of amino acid in VHHs were closely related to the solubility of VHH molecules during refolding. The genetic fusion of PMMA-tag to C-terminal region of VHHs significantly affects the recovery of their soluble protein during refolding by 50 mM TAPS at pH 8.5. It could be refolded with a recovery of more than 95% by dialysis at pH 8.5. A marked difference in the antigen-binding activities in the adsorption state was significantly high in VHH-PM compared to the wild type of VHH. There are approximately 8-fold differences in the antigen-binding activities in the adsorption state between VHH-PM and VHH.Keywords: VHH, PMMA-tag, isoelectric point, pH, Solubility, refolding, immobilization, ELISA
Procedia PDF Downloads 4192607 A Review of Material and Methods Used in Liner Layers in Various Landfills
Authors: S. Taghvamanesh
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Modern landfills are highly engineered containment systems that are designed to reduce the environmental and human health impacts of solid waste (trash). In modern landfills, waste is contained by a liner system. The primary goal of the liner system is to isolate the landfill contents from the environment, thereby protecting the soil and groundwater from pollution caused by the leachate of a landfill. Landfill leachate is the most serious threat to groundwater. Therefore, it is necessary to design a system that prevents the penetration of this dangerous substance into the environment. These layers are made up of two basic elements: clay and geosynthetics. Hydraulic conductivity and flexibility are two desirable properties of these materials. There are three different types of liner systems that will be discussed in this paper. According to available data, the current article analyzed materials and methods for constructing liner layers made of distinct leachates, including various harmful components and heavy metals from all around the world. Also, this study attempted to gather data on leachates for each of the sites discussed. In conclusion, every landfill requires a specific type of liner, which depends on the type of leachate that it produces daily. It should also be emphasized that, based on available data, this article focused on the number of landfills that each country or continent possesses.Keywords: landfill, liner layer, impervious layer, barrier layer
Procedia PDF Downloads 772606 Assessment of Drinking Water Contamination from the Water Source to the Consumer in Palapye Region, Botswana
Authors: Tshegofatso Galekgathege
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Poor water quality is of great concern to human health as it can cause disease outbreaks. A standard practice today, in developed countries, is that people should be provided with safe-reliable drinking water, as safe drinking water is recognized as a basic human right and a cost effective measure of reducing diseases. Over 1.1 billion people worldwide lack access to a safe water supply and as a result, the majority are forced to use polluted surface or groundwater. It is widely accepted that our water supply systems are susceptible to the intentional or accidental contamination .Water quality degradation may occur anywhere in the path that water takes from the water source to the consumer. Chlorine is believed to be an effective tool in disinfecting water, but its concentration may decrease with time due to consumption by chemical reactions. This shows that we are at the risk of being infected by waterborne diseases if chlorine in water falls below the required level of 0.2-1mg/liter which should be maintained in water and some contaminants enter into the water distribution system. It is believed that the lack of adequate sanitation also contributes to the contamination of water globally. This study therefore, assesses drinking water contamination from the source to the consumer by identifying the point vulnerable to contamination from the source to the consumer in the study area .To identify the point vulnerable to contamination, water was sampled monthly from boreholes, water treatment plant, water distribution system (WDS), service reservoirs and consumer taps from all the twenty (20) villages of Palapye region. Sampled water was then taken to the laboratory for testing and analysis of microbiological and chemical parameters. Water quality analysis were then compared with Botswana drinking water quality standards (BOS32:2009) to see if they comply. Major sources of water contamination identified during site visits were the livestock which were found drinking stagnant water from leaking pipes in 90 percent of the villages. Soils structure around the area was negatively affected because of livestock movement even vegetation in the area. In conclusion microbiological parameters of water in the study area do not comply with drinking water standards, some microbiological parameters in water indicated that livestock do not only affect land degradation but also the quality of water. Chlorine has been applied to water over some years but it is not effective enough thus preventative measures have to be developed, to prevent contaminants from reaching water. Remember: Prevention is better than cure.Keywords: land degradation, leaking systems, livestock, water contamination
Procedia PDF Downloads 3522605 Assessing Organizational Resilience Capacity to Flooding: Index Development and Application to Greek Small & Medium-Sized Enterprises
Authors: Antonis Skouloudis, Konstantinos Evangelinos, Walter Leal-Filho, Panagiotis Vouros, Ioannis Nikolaou
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Organizational resilience capacity to extreme weather events (EWEs) has sparked a growth in scholarly attention over the past decade as an essential aspect in business continuity management, with supporting evidence for this claim to suggest that it retains a key role in successful responses to adverse situations, crises and shocks. Small and medium-sized enterprises (SMEs) are more vulnerable to face floods compared to their larger counterparts, so they are disproportionately affected by such extreme weather events. The limited resources at their disposal, the lack of time and skills all conduce to inadequate preparedness to challenges posed by floods. SMEs tend to plan in the short-term, reacting to circumstances as they arise and focussing on their very survival. Likewise, they share less formalised structures and codified policies while they are most usually owner-managed, resulting in a command-and-control management culture. Such characteristics result in them having limited opportunities to recover from flooding and quickly turnaround their operation from a loss making to a profit making one. Scholars frame the capacity of business entities to be resilient upon an EWE disturbance (such as flash floods) as the rate of recovery and restoration of organizational performance to pre-disturbance conditions, the amount of disturbance (i.e. threshold level) a business can absorb before losing structural and/or functional components that will alter or cease operation, as well as the extent to which the organization maintains its function (i.e. impact resistance) before performance levels are driven to zero. Nevertheless, while it seems to be accepted as an essential trait of firms effectively transcending uncertain conditions, research deconstructing the enabling conditions and/or inhibitory factors of SMEs resilience capacity to natural hazards is still sparse, fragmentary and mostly fuelled by anecdotal evidence or normative assumptions. Focusing on the individual level of analysis, i.e. the individual enterprise and its endeavours to succeed, the emergent picture from this relatively new research strand delineates the specification of variables, conceptual relationships or dynamic boundaries of resilience capacity components in an attempt to provide prescriptions for policy-making as well as business management. This study will present the development of a flood resilience capacity index (FRCI) and its application to Greek SMEs. The proposed composite indicator pertains to cognitive, behavioral/managerial and contextual factors that influence an enterprise’s ability to shape effective responses to meet flood challenges. Through the proposed indicator-based approach, an analytical framework is set forth that will help standardize such assessments with the overarching aim of reducing the vulnerability of SMEs to flooding. This will be achieved by identifying major internal and external attributes explaining resilience capacity which is particularly important given the limited resources these enterprises have and that they tend to be primary sources of vulnerabilities in supply chain networks, generating Single Points of Failure (SPOF).Keywords: Floods, Small & Medium-Sized enterprises, organizational resilience capacity, index development
Procedia PDF Downloads 1892604 Capacity Estimation of Hybrid Automated Repeat Request Protocol for Low Earth Orbit Mega-Constellations
Authors: Arif Armagan Gozutok, Alper Kule, Burak Tos, Selman Demirel
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Wireless communication chain requires effective ways to keep throughput efficiency high while it suffers location-dependent, time-varying burst errors. Several techniques are developed in order to assure that the receiver recovers the transmitted information without errors. The most fundamental approaches are error checking and correction besides re-transmission of the non-acknowledged packets. In this paper, stop & wait (SAW) and chase combined (CC) hybrid automated repeat request (HARQ) protocols are compared and analyzed in terms of throughput and average delay for the usage of low earth orbit (LEO) mega-constellations case. Several assumptions and technological implementations are considered as well as usage of low-density parity check (LDPC) codes together with several constellation orbit configurations.Keywords: HARQ, LEO, satellite constellation, throughput
Procedia PDF Downloads 1452603 Bifunctional Activity and Stability of Fused Plasmodium falciparum Orotate Phosphoribosyltransferase and Orotidine 5′-Monophosphate Decarboxylase
Authors: Patsarawadee Paojinda, Waranya Imprasittichai, Sudaratana R. Krungkrai, Nirianne Marie Q. Palacpac, Toshihiro Horii, Jerapan Krungkrai
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Fusion of the last two enzymes in the pyrimidine biosynthetic pathway in the inversed order by having COOH-terminal orotate phosphoribosyltransferase (OPRT) and NH2-terminal orotidine 5'-monophosphate decarboxylase (OMPDC), as OMPDC-OPRT, are described in many organisms. Here, we produced gene fusions of Plasmodium falciparum OMPDC-OPRT and expressed the bifunctional protein in Escherichia coli. The enzyme was purified to homogeneity using affinity and anion-exchange chromatography, exhibited enzymatic activities and functioned as a dimer. The activities, although unstable, can be stabilized by its substrate and product during purification and long-term storage. Furthermore, the enzyme expressed a perfect catalytic efficiency (kcat/Km). The kcat was selectively enhanced up to 3 orders of magnitude, while the Km was not much affected and remained at low µM levels when compared to the monofunctional enzymes. The fusion of the two enzymes, creating a “super-enzyme” with perfect catalytic power and more flexibility, reflects cryptic relationship of enzymatic reactivaties and metabolic functions on molecular evolution.Keywords: bifunctional enzyme, orotate phosphoribosyltransferase, orotidine 5'-monophosphate decarboxylase, plasmodium falciparum
Procedia PDF Downloads 2852602 New Scheme of Control and Air Supply in a Low-Power Hot Water Boiler
Authors: М. Zh. Khazimov, А. B. Kudasheva
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The article presents the state of solid fuel reserves and their share in the world energy sector. The air pollution caused by the operation of heating devices using solid fuels is a significant problem. In order to improve the air quality, heating device producers take constant measures to improve their products. However, the emission results achieved during an initial test of heating devices in the laboratory may be much worse during operation in real operating conditions. The ways of increasing the efficiency of the boiler by improving its design for combustion in full-layer mode are shown. The results of the testing of the improved КВТС-0.2 hot water boiler is presented and the technical and economic indicators are determined, which indicate an increase in the efficiency of the boiler.Keywords: boiler unit, grate, furnace, coal, ash
Procedia PDF Downloads 702601 Affective (And Effective) Teaching and Learning: Higher Education Gets Social Again
Authors: Laura Zizka, Gaby Probst
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The Covid-19 pandemic has affected the way Higher Education Institutions (HEIs) have given their courses. From emergency remote where all students and faculty were immediately confined to home teaching and learning, the continuing evolving sanitary situation obliged HEIs to adopt other methods of teaching and learning from blended courses that included both synchronous and asynchronous courses and activities to hy-flex models where some students were on campus while others followed the course simultaneously online. Each semester brought new challenges for HEIs and, subsequently, additional emotional reactions. This paper investigates the affective side of teaching and learning in various online modalities and its toll on students and faculty members over the past three semesters. The findings confirm that students and faculty who have more self-efficacy, flexibility, and resilience reported positive emotions and embraced the opportunities that these past semesters have offered. While HEIs have begun a new semester in an attempt to return to ‘normal’ face-to-face courses, this paper posits that there are lessons to be learned from these past three semesters. The opportunities that arose from the challenge of the pandemic should be considered when moving forward by focusing on a greater emphasis on the affective aspect of teaching and learning in HEIs worldwide.Keywords: effective teaching and learning, higher education, engagement, interaction, motivation
Procedia PDF Downloads 1172600 Complex Dynamics of a Four Species Food-Web Model: An Analysis through Beddington-Deangelis Functional Response in the Presence of Additional Food
Authors: Surbhi Rani, Sunita Gakkhar
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The four-dimensional food web system consisting of two prey species for a generalist middle predator and a top predator is proposed and investigated. The middle predator is predating both the prey species with a modified Holling type-II functional response. The food web model is found to be well-posed, bounded, and dissipative. The proposed model's essential dynamical features are studied in terms of local stability. The four species' survival is explored, and persistence conditions are established. The numerical simulations reveal the persistence in the form of a chaotic attractor or stable focus. The conclusion is that providing additional food to the middle predator may help to control the food chain's chaos.Keywords: predator-prey model, existence of equilibrium points, local stability, chaos, numerical simulations
Procedia PDF Downloads 1092599 Automated Testing of Workshop Robot Behavior
Authors: Arne Hitzmann, Philipp Wentscher, Alexander Gabel, Reinhard Gerndt
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Autonomous mobile robots can be found in a wide field of applications. Their types range from household robots over workshop robots to autonomous cars and many more. All of them undergo a number of testing steps during development, production and maintenance. This paper describes an approach to improve testing of robot behavior. It was inspired by the RoboCup @work competition that itself reflects a robotics benchmark for industrial robotics. There, scaled down versions of mobile industrial robots have to navigate through a workshop-like environment or operation area and have to perform tasks of manipulating and transporting work pieces. This paper will introduce an approach of automated vision-based testing of the behavior of the so called youBot robot, which is the most widely used robot platform in the RoboCup @work competition. The proposed system allows automated testing of multiple tries of the robot to perform a specific missions and it allows for the flexibility of the robot, e.g. selecting different paths between two tasks within a mission. The approach is based on a multi-camera setup using, off the shelf cameras and optical markers. It has been applied for test-driven development (TDD) and maintenance-like verification of the robot behavior and performance.Keywords: supervisory control, testing, markers, mono vision, automation
Procedia PDF Downloads 3772598 Development of Colorimetric Based Microfluidic Platform for Quantification of Fluid Contaminants
Authors: Sangeeta Palekar, Mahima Rana, Jayu Kalambe
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In this paper, a microfluidic-based platform for the quantification of contaminants in the water is proposed. The proposed system uses microfluidic channels with an embedded environment for contaminants detection in water. Microfluidics-based platforms present an evident stage of innovation for fluid analysis, with different applications advancing minimal efforts and simplicity of fabrication. Polydimethylsiloxane (PDMS)-based microfluidics channel is fabricated using a soft lithography technique. Vertical and horizontal connections for fluid dispensing with the microfluidic channel are explored. The principle of colorimetry, which incorporates the use of Griess reagent for the detection of nitrite, has been adopted. Nitrite has high water solubility and water retention, due to which it has a greater potential to stay in groundwater, endangering aquatic life along with human health, hence taken as a case study in this work. The developed platform also compares the detection methodology, containing photodetectors for measuring absorbance and image sensors for measuring color change for quantification of contaminants like nitrite in water. The utilization of image processing techniques offers the advantage of operational flexibility, as the same system can be used to identify other contaminants present in water by introducing minor software changes.Keywords: colorimetric, fluid contaminants, nitrite detection, microfluidics
Procedia PDF Downloads 1982597 A Social-Environmental Way for Production of Building Materials with Solid Residues
Authors: Flavio Araujo, Julio Lima, Paulo Scalize, Antonio Albuquerque
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Water treatment residues (WTR) are produced during water treatment and have recently been seen as a reusable material. The aim of this research was to perform characterizations of the residue generated in the Meia-Ponte Water Treatment Plant, in Goiania, Brazil, seeking to obtain normative parameters and consider sustainable alternatives for reincorporation of the residues in the productive chain for manufacturing various materials construction. In order to reduce the environmental liabilities generated by sanitation companies and discontinue unsustainable forms of disposal. The analyzes performed: Granulometry, Scanning Electron Microscopy, and X-Ray Diffraction demonstrated the potential application of residues to replace the soil and sand, because it has characteristics compatible with small aggregate and can be used as feed stock for the manufacture of materials as ceramic and soil-cement bricks, mortars, interlocking floors and concrete artifacts.Keywords: residue, sustainable, water treatment plants, WTR
Procedia PDF Downloads 548