Search results for: biologically active substances
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 4279

Search results for: biologically active substances

1549 Intensive Use of Software in Teaching and Learning Calculus

Authors: Nodelman V.

Abstract:

Despite serious difficulties in the assimilation of the conceptual system of Calculus, software in the educational process is used only occasionally, and even then, mainly for illustration purposes. The following are a few reasons: The non-trivial nature of the studied material, Lack of skills in working with software, Fear of losing time working with software, The variety of the software itself, the corresponding interface, syntax, and the methods of working with the software, The need to find suitable models, and familiarize yourself with working with them, Incomplete compatibility of the found models with the content and teaching methods of the studied material. This paper proposes an active use of the developed non-commercial software VusuMatica, which allows removing these restrictions through Broad support for the studied mathematical material (and not only Calculus). As a result - no need to select the right software, Emphasizing the unity of mathematics, its intrasubject and interdisciplinary relations, User-friendly interface, Absence of special syntax in defining mathematical objects, Ease of building models of the studied material and manipulating them, Unlimited flexibility of models thanks to the ability to redefine objects, which allows exploring objects characteristics, and considering examples and counterexamples of the concepts under study. The construction of models is based on an original approach to the analysis of the structure of the studied concepts. Thanks to the ease of construction, students are able not only to use ready-made models but also to create them on their own and explore the material studied with their help. The presentation includes examples of using VusuMatica in studying the concepts of limit and continuity of a function, its derivative, and integral.

Keywords: counterexamples, limitations and requirements, software, teaching and learning calculus, user-friendly interface and syntax

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1548 Impact of a Locally-Prepared Fermented Alcoholic Beverage from Jaggery on the Gut Bacterial Profile of the Tea-Tribal Populations of Assam, India

Authors: Rupamoni Thakur, Madhusmita Dehingia, Narayan C. Talukdar, Mojibur R. Khan

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The human gut is an extremely active fermentation site and is inhabited by diverse bacterial species. Consumption of alcoholic beverages has been shown to substantially modulate the human gut bacterial profile (GBP) of an individual. Assam, a major north-eastern state of India, is home to a number of tribal populations of which the tea-tribes form a major community. These tea-tribal communities are known to prepare and consume a locally-prepared alcoholic beverage from fermented jaggery, whose chemical composition is unknown. In this study, we demonstrate the effect of daily intake of the locally-prepared alcoholic beverage on the GBP of the tea-tribal communities and correlate it with the changes in the biochemical biomarkers of the population. The fecal bacterial diversity of 40 drinkers and 35 non-drinking healthy individuals were analyzed by polymerase chain reaction (PCR)–denaturing gradient gel electrophoresis (DGGE). The results suggested that the GBP was significantly modulated in the fermented-beverage consuming subjects. Significant difference was also observed in the serum biochemical parameters such as triglyceride, total cholesterol and the liver marker enzymes (ASAT/ALAT and GGT). Further studies to identify the GBP of drinkers vs non-drinkers through Next-generation Sequencing (NGS) analysis and to correlate the changes with the biochemical biomarkers of the population is underway.

Keywords: alcoholic beverage, gut bacterial profile, PCR-DGGE analysis, tea-tribes of India

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1547 Following the Modulation of Transcriptional Activity of Genes by Chromatin Modifications during the Cell Cycle in Living Cells

Authors: Sharon Yunger, Liat Altman, Yuval Garini, Yaron Shav-Tal

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Understanding the dynamics of transcription in living cells has improved since the development of quantitative fluorescence-based imaging techniques. We established a method for following transcription from a single copy gene in living cells. A gene tagged with MS2 repeats, used for mRNA tagging, in its 3' UTR was integrated into a single genomic locus. The actively transcribing gene was detected and analyzed by fluorescence in situ hybridization (FISH) and live-cell imaging. Several cell clones were created that differed in the promoter regulating the gene. Thus, comparative analysis could be obtained without the risk of different position effects at each integration site. Cells in S/G2 phases could be detected exhibiting two adjacent transcription sites on sister chromatids. A sharp reduction in the transcription levels was observed as cells progressed along the cell cycle. We hypothesized that a change in chromatin structure acts as a general mechanism during the cell cycle leading to down-regulation in the activity of some genes. We addressed this question by treating the cells with chromatin decondensing agents. Quantifying and imaging the treated cells suggests that chromatin structure plays a role both in regulating transcriptional levels along the cell cycle, as well as in limiting an active gene from reaching its maximum transcription potential at any given time. These results contribute to understanding the role of chromatin as a regulator of gene expression.

Keywords: cell cycle, living cells, nucleus, transcription

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1546 Physics Recitations for College Physics Courses Using Breakout Rooms during COVID Pandemic

Authors: Pratheesh Jakkala

Abstract:

This paper addresses the use of breakout sessions to conduct successful weekly physics recitations for College Physics I and II at a large University in remote teaching method during COVID-19 pandemic. All breakout sessions are synchronous, conducted live, and handled by teaching assistants. A two-prong approach is used to maintain the integrity of recitations. Three different conference platforms WebEx, Zoom, and Canvas conferences, were tested, and BigBlue button using Canvas was adopted. The results and experiences of all three learning platforms are presented in this paper. Recitation questions were assigned on WebAssign learning platform and a standard five-question template developed by the instructor was used for group discussions and active peer-peer engagement. Breakout sessions feature of BigBlueButton in Canvas conferences was successfully implemented. Each breakout session consists of a team of 4 students. An online whiteboard, chat window options were used for live teamwork. Student peer-peer interactions, Teaching Assistants’ interaction with students were video and audio recorded. A total of 72 students in College Physics II and 55 students in College Physics I was enrolled. 82% of students agreed that method under study is better than previous methods. The study addressed the quality of student teamwork, student attitude towards problem-solving, and student performance in the exams.

Keywords: recitations, breakout rooms, online learning platforms, COVID pandemic

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1545 Finite Element Analysis of Raft Foundation on Various Soil Types under Earthquake Loading

Authors: Qassun S. Mohammed Shafiqu, Murtadha A. Abdulrasool

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The design of shallow foundations to withstand different dynamic loads has given considerable attention in recent years. Dynamic loads may be due to the earthquakes, pile driving, blasting, water waves, and machine vibrations. But, predicting the behavior of shallow foundations during earthquakes remains a difficult task for geotechnical engineers. A database for dynamic and static parameters for different soils in seismic active zones in Iraq is prepared which has been collected from geophysical and geotechnical investigation works. Then, analysis of a typical 3-D soil-raft foundation system under earthquake loading is carried out using the database. And a parametric study has been carried out taking into consideration the influence of some parameters on the dynamic behavior of the raft foundation, such as raft stiffness, damping ratio as well as the influence of the earthquake acceleration-time records. The results of the parametric study show that the settlement caused by the earthquake can be decreased by about 72% with increasing the thickness from 0.5 m to 1.5 m. But, it has been noticed that reduction in the maximum bending moment by about 82% was predicted by decreasing the raft thickness from 1.5 m to 0.5 m in all sites model. Also, it has been observed that the maximum lateral displacement, the maximum vertical settlement and the maximum bending moment for damping ratio 0% is about 14%, 20%, and 18% higher than that for damping ratio 7.5%, respectively for all sites model.

Keywords: shallow foundation, seismic behavior, raft thickness, damping ratio

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1544 The Relationship between Infill Development Indicators and Quality of Life in Urban Neighborhoods

Authors: S. Mohammad Reza Khatibi

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Statistics on urbanization in Iran and around the world show that urbanization rate and urban population had had an increasing growth and, during five decades, this trend shows the fact that growth will still continue for a long time. Therefore, instead of an irregular horizontal city development and growth, a sustainable development is achievable by filling the existing city fabric, organizing the density and changing the use of incompatible old or urban buildings. One approach is the infill development. Infill development is the development of vacant land or wasteland abandoned within built areas or where there already exist facilities and equipment. Simply put, infill development is the use of empty spaces or those lacking intra-city use for city development. Additionally, fulfillment of social justice and creating a safe, secure and desirable atmosphere for citizens to live and stay active along with acquiring equal life opportunities, are among the goals of vision plan of Iran in conflict with which, certain environments have been created by city neighborhoods having physical, social, economic, etc. problems. Accordingly, in order to meet the extensive need of many cities for openness to growing population, this paper aims to investigate the relationship between infill development indicators and life quality in urban neighborhoods, using descriptive-analytical research method. Findings show that infill development indicators in three physical, social and economic categories can be adapted with quality components of urban environments, especially urban neighborhoods, and related guidelines can be offered.

Keywords: infill development, life quality, urban neighborhoods, indicator

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1543 Bacterial Cellulose/Silver-Doped Hydroxyapatite Composites for Tissue Engineering Application

Authors: Adrian Ionut Nicoara, Denisa Ionela Ene, Alina Maria Holban, Cristina Busuioc

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At present, the development of materials with biomedical applications is a domain of interest that will produce a full series of benefits in engineering and medicine. In this sense, it is required to use a natural material, and this paper is focused on the development of a composite material based on bacterial cellulose – hydroxyapatite and silver nanoparticles with applications in hard tissue. Bacterial cellulose own features like biocompatibility, non-toxicity character and flexibility. Moreover, the bacterial cellulose can be conjugated with different forms of active silver to possess antimicrobial activity. Hydroxyapatite is well known that can mimic at a significant level the activity of the initial bone. The material was synthesized by using an ultrasound probe and finally characterized by several methods. Thereby, the morphological properties were analyzed by using Scanning Electron Microscopy (SEM) and Transmission Electron Microscopy (TEM). Because the synthesized material has medical application in restore the tissue and to fight against microbial invasion, the samples were tested from the biological point of view by evaluating the biodegradability in phosphate-buffered saline (PBS) and simulated body fluid (SBF) and moreover the antimicrobial effect was performed on Gram-positive bacterium Staphylococcus aureus, Gram-negative bacterium Escherichia coli, and fungi Candida albicans. The results reveal that the obtained material has specific characteristics for bone regeneration.

Keywords: bacterial cellulose, biomaterials, hydroxyapatite, scaffolds materials

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1542 Effect of Site Amplification on Seismic Safety Evaluation of Flyover Pier

Authors: Mohammad Raihan Mukhlis, M. Abdur Rahman Bhuiyan

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Bangladesh is a developing country in which a lot of multi-span simply/continuous supported flyovers are being constructed in its major cities. Being situated in a seismically active region, seismic safety evaluation of flyovers is essential for seismic risk reduction. Effects of site amplification on seismic safety evaluation of flyover piers are the main concern of this study. In this regard, failure mode, lateral strength and displacement ductility of piers of a typical multi-span simply supported flyover have been evaluated by Japan Road Association (JRA) recommended guidelines, with and without considering site amplification. Ultimate flexural strengths of piers have been computed using the pushover analysis results. Shear capacity of piers has been calculated using the guidelines of JRA. Lateral strengths have been determined depending on the failure modes of the piers. Displacement ductility of piers has been computed using yield and ultimate displacements of the piers obtained from the pushover analysis results. Selected earthquake time history is used in seismic safety evaluation of the flyover piers. Finally, the ductility design method is used to conduct the seismic safety evaluation of the piers with and without considering site amplification. From the numerical results, it has been revealed that the effects of site amplification on seismic safety evaluation of bridge structures should be carefully taken into account.

Keywords: displacement ductility, flyover pier, lateral strength, safety evaluation, site amplification

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1541 Assessment of Biofilm Production Capacity of Industrially Important Bacteria under Electroinductive Conditions

Authors: Omolola Ojetayo, Emmanuel Garuba, Obinna Ajunwa, Abiodun A. Onilude

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Introduction: Biofilm is a functional community of microorganisms that are associated with a surface or an interface. These adherent cells become embedded within an extracellular matrix composed of polymeric substances, i.e., biofilms refer to biological deposits consisting of both microbes and their extracellular products on biotic and abiotic surfaces. Despite their detrimental effects in medicine, biofilms as natural cell immobilization have found several applications in biotechnology, such as in the treatment of wastewater, bioremediation and biodegradation, desulfurization of gas, and conversion of agro-derived materials into alcohols and organic acids. The means of enhancing immobilized cells have been chemical-inductive, and this affects the medium composition and final product. Physical factors including electrical, magnetic, and electromagnetic flux have shown potential for enhancing biofilms depending on the bacterial species, nature, and intensity of emitted signals, the duration of exposure, and substratum used. However, the concept of cell immobilisation by electrical and magnetic induction is still underexplored. Methods: To assess the effects of physical factors on biofilm formation, six American typed culture collection (Acetobacter aceti ATCC15973, Pseudomonas aeruginosa ATCC9027, Serratia marcescens ATCC14756, Gluconobacter oxydans ATCC19357, Rhodobacter sphaeroides ATCC17023, and Bacillus subtilis ATCC6633) were used. Standard culture techniques for bacterial cells were adopted. Natural autoimmobilisation potentials of test bacteria were carried out by simple biofilms ring formation on tubes, while crystal violet binding assay techniques were adopted in the characterisation of biofilm quantity. Electroinduction of bacterial cells by direct current (DC) application in cell broth, static magnetic field exposure, and electromagnetic flux were carried out, and autoimmobilisation of cells in a biofilm pattern was determined on various substrata tested, including wood, glass, steel, polyvinylchloride (PVC) and polyethylene terephthalate. Biot Savart law was used in quantifying magnetic field intensity, and statistical analyses of data obtained were carried out using the analyses of variance (ANOVA) as well as other statistical tools. Results: Biofilm formation by the selected test bacteria was enhanced by the physical factors applied. Electromagnetic induction had the greatest effect on biofilm formation, with magnetic induction producing the least effect across all substrata used. Microbial cell-cell communication could be a possible means via which physical signals affected the cells in a polarisable manner. Conclusion: The enhancement of biofilm formation by bacteria using physical factors has shown that their inherent capability as a cell immobilization method can be further optimised for industrial applications. A possible relationship between the presence of voltage-dependent channels, mechanosensitive channels, and bacterial biofilms could shed more light on this phenomenon.

Keywords: bacteria, biofilm, cell immobilization, electromagnetic induction, substrata

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1540 Succeeding through Disruption: Exploring the Factors Influencing the Adoption of Disruptive Technologies in the Mobile Telecommunications Industry in Zimbabwe

Authors: Africa Makasi

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The research explored factors influencing the adoption of disruptive technologies in the mobile telecommunications industry in Zimbabwe. Data was gathered from the second biggest competitor in the industry with over 3 million subscribers as the main case of study. The survey was conducted by purposively selecting 70 respondents from a population of 3,000,000 (three million) active subscribers from the company’s database. A skip interval of 42,857 was used to randomly select the sample. Customer representatives were selected from the company’s five regional offices using a two-stage cluster sampling technique. Employee participants were purposively selected from the company’s head office. Self-administered questionnaires were used in the research. A pilot test was conducted and the assessment of the reliability of the research instruments used in the research performed. Results of the pilot study were analyzed to test for reliability using SPSS. The results confirmed that the style of leadership and its thrust may help speed up or reduce the adoption of disruptive technologies. This was reflected by a p–value of 0.01 which is less than 0.05. The null hypothesis was thus rejected and the strong relationship between leadership and adoption of disruptive technology is confirmed. Similar results were also obtained with respect to staff competence, availability of funding and the type of infrastructure available Future research should look at organizational ambidexterity as well as exploitation and exploration paradigms in organizations in the telecommunications industry and their impact on the adoption of disruptive technologies.

Keywords: disruptive innovation, adoption, mobile telecommunication industry, exploration and exploitation

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1539 Geochemistry Identification of Volcanic Rocks Product of Krakatau Volcano Eruption for Katastropis Mitigation Planning

Authors: Agil Gemilang Ramadhan, Novian Triandanu

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Since 1929, the first appearance in sea level, Anak Krakatau volcano growth relatively quickly. During the 80 years up to 2010 has reached the height of 320 meter above sea level. The possibility of catastrophic explosive eruption could happen again if the chemical composition of rocks from the eruption changed from alkaline magma into acid magma. Until now Anak Krakatau volcanic activity is still quite active as evidenced by the frequency of eruptions that produced ash sized pyroclastic deposits - bomb. Purpose of this study was to identify changes in the percentage of rock geochemistry any results eruption of Anak Krakatau volcano to see consistency change the percentage content of silica in the magma that affect the type of volcanic eruptions. Results from this study will be produced in the form of a diagram the data changes the chemical composition of rocks of Anak Krakatau volcano. Changes in the composition of any silica eruption are illustrated in a graph. If the increase in the percentage of silica is happening consistently and it is assumed to increase in the time scale of a few percent, then to achieve silica content of 68 % (acid composition) that will produce an explosive eruption will know the approximate time. All aspects of the factors driving the increased threat of danger to the public should be taken into account. Catastrophic eruption katatropis mitigation can be planned early so that when these disasters happen later, casualties can be minimized.

Keywords: Krakatau volcano, rock geochemistry, catastrophic eruption, mitigation

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1538 Modified Gold Screen Printed Electrode with Ruthenium Complex for Selective Detection of Porcine DNA

Authors: Siti Aishah Hasbullah

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Studies on identification of pork content in food have grown rapidly to meet the Halal food standard in Malaysia. The used mitochondria DNA (mtDNA) approaches for the identification of pig species is thought to be the most precise marker due to the mtDNA genes are present in thousands of copies per cell, the large variability of mtDNA. The standard method commonly used for DNA detection is based on polymerase chain reaction (PCR) method combined with gel electrophoresis but has major drawback. Its major drawbacks are laborious, need longer time and toxic to handle. Therefore, the need for simplicity and fast assay of DNA is vital and has triggered us to develop DNA biosensors for porcine DNA detection. Therefore, the aim of this project is to develop electrochemical DNA biosensor based on ruthenium (II) complex, [Ru(bpy)2(p-PIP)]2+ as DNA hybridization label. The interaction of DNA and [Ru(bpy)2(p-HPIP)]2+ will be studied by electrochemical transduction using Gold Screen-Printed Electrode (GSPE) modified with gold nanoparticles (AuNPs) and succinimide acrylic microspheres. The electrochemical detection by redox active ruthenium (II) complex was measured by cyclic voltammetry (CV) and differential pulse voltammetry (DPV). The results indicate that the interaction of [Ru(bpy)2(PIP)]2+ with hybridization complementary DNA has higher response compared to single-stranded and mismatch complementary DNA. Under optimized condition, this porcine DNA biosensor incorporated modified GSPE shows good linear range towards porcine DNA.

Keywords: gold, screen printed electrode, ruthenium, porcine DNA

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1537 Engaging Girls in 'Learn Science by Doing' as Strategy for Enhanced Learning Outcome at the Junior High School Level in Nigeria

Authors: Stella Y. Erinosho

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In an attempt to impact on girls’ interest in science, an instructional package on ‘Learn Science by Doing (LSD)’ was developed to support science teachers in teaching integrated science at the junior secondary level in Nigeria. LSD provides an instructional framework aimed at actively engaging girls in beginners’ science through activities that are discovery-oriented and allow for experiential learning. The goal of this study was to show the impact of application of LSD on girls’ performance and interest in science. The major hypothesis that was tested in the study was that students would exhibit higher learning outcomes (achievement and attitude) in science as effect of exposure to LSD instructional package. A quasi-experimental design was adopted, incorporating four all-girls schools. Three of the schools (comprising six classes) were randomly designated as experimental and one as the control. The sample comprised 357 girls (275 experimental and 82 control) and nine science teachers drawn from the experimental schools. The questionnaire was designed to gather data on students’ background characteristics and their attitude toward science while the cognitive outcomes were measured using tests, both within a group and between groups, the girls who had exposure to LSD exhibited improved cognitive outcomes and more positive attitude towards science compared with those who had conventional teaching. The data are consistent with previous studies indicating that interactive learning activities increase student performance and interest.

Keywords: active learning, school science, teaching and learning, Nigeria

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1536 Regenerative Agriculture Standing at the Intersection of Design, Mycology, and Soil Fertility

Authors: Andrew Gennett

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Designing for fungal development means embracing the symbiotic relationship between the living system and built environment. The potential of mycelium post-colonization is explored for the fabrication of advanced pure mycelium products, going beyond the conventional methods of aggregating materials. Fruiting induction imparts desired material properties such as enhanced environmental resistance. Production approach allows for simultaneous generation of multiple products while scaling up raw materials supply suitable for architectural applications. The following work explores the integration of fungal environmental perception with computational design of built fruiting chambers. Polyporales, are classified by their porous reproductive tissues supported by a wood-like context tissue covered by a hard waterproofing coat of hydrobpobins. Persisting for years in the wild, these species represent material properties that would be highly desired in moving beyond flat sheets of arial mycelium as with leather or bacon applications. Understanding the inherent environmental perception of fungi has become the basis for working with and inducing desired hyphal differentiation. Working within the native signal interpretation of a mycelium mass during fruiting induction provides the means to apply textures and color to the final finishing coat. A delicate interplay between meeting human-centered goals while designing around natural processes of living systems represents a blend of art and science. Architecturally, physical simulations inform model design for simple modular fruiting chambers that change as fungal growth progresses, while biological life science principles describe the internal computations occurring within the fungal hyphae. First, a form filling phase of growth is controlled by growth chamber environment. Second, an initiation phase of growth forms the final exterior finishing texture. Hyphal densification induces cellular cascades, in turn producing the classical hardened cuticle, UV protective molecule production, as well, as waterproofing finish. Upon fruiting process completion, the fully colonized spent substrate holds considerable value and is not considered waste. Instead, it becomes a valuable resource in the next cycle of production scale-up. However, the acquisition of new substrate resources poses a critical question, particularly as these resources become increasingly scarce. Pursuing a regenerative design paradigm from the environmental perspective, the usage of “agricultural waste” for architectural materials would prove a continuation of the destructive practices established by the previous industrial regime. For these residues from fields and forests serve a vital ecological role protecting the soil surface in combating erosion while reducing evaporation and fostering a biologically diverse food web. Instead, urban centers have been identified as abundant sources of new substrate material. Diverting the waste from secondary locations such as food processing centers, papers mills, and recycling facilities not only reduces landfill burden but leverages the latent value of these waste steams as precious resources for mycelium cultivation. In conclusion, working with living systems through innovative built environments for fungal development, provides the needed gain of function and resilience of mycelium products. The next generation of sustainable fungal products will go beyond the current binding process, with a focus upon reducing landfill burden from urban centers. In final considerations, biophilic material builds to an ecologically regenerative recycling production cycle.

Keywords: regenerative agriculture, mycelium fabrication, growth chamber design, sustainable resource acquisition, fungal morphogenesis, soil fertility

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1535 Electrokinetic Regulation of Flow in Microcrack Reservoirs

Authors: Aslanova Aida Ramiz

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One of the important aspects of rheophysical problems in oil and gas extraction is the regulation of thermohydrodynamic properties of liquid systems using physical and physicochemical methods. It is known that the constituent parts of real fluid systems in oil and gas production are practically non-conducting, non-magnetically active components. Real heterogeneous hydrocarbon systems, from the structural point of view, consist of an infinite number of microscopic local ion-electrostatic cores distributed in the volume of the dispersion medium. According to Cohen's rule, double electric layers are formed at the contact boundaries of components in contact (oil-gas, oil-water, water-condensate, etc.) in a heterogeneous system, and as a result, each real fluid system can be represented as a complex composition of a set of local electrostatic fields. The electrokinetic properties of this structure are characterized by a certain electrode potential. Prof. F.H. Valiyev called this potential the α-factor and came up with the idea that many natural and technological rheophysical processes (effects) are essentially electrokinetic in nature, and by changing the α-factor, it is possible to adjust the physical properties of real hydraulic systems, including thermohydrodynamic parameters. Based on this idea, extensive research work was conducted, and the possibility of reducing hydraulic resistances and improving rheological properties was experimentally discovered in real liquid systems by reducing the electrical potential with various physical and chemical methods.

Keywords: microcracked, electrode potential, hydraulic resistance, Newtonian fluid, rheophysical properties

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1534 Impact of Team-Based Learning Approach in English Language Learning Process: A Case Study of Universidad Federico Santa Maria

Authors: Yessica A. Aguilera

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English is currently the only foreign language included in the national educational curriculum in Chile. The English curriculum establishes that once completed secondary education, students are expected to reach B1 level according to the Common European Reference Framework (CEFR) scale. However, the objective has not been achieved, and to the author’s best knowledge, there is still a severe lack of English language skills among students who have completed their secondary education studies. In order to deal with the fact that students do not manage English as expected, team-based learning (TBL) was introduced in English language lessons at the Universidad Federico Santa María (USM). TBL is a collaborative teaching-learning method which enhances active learning by combining individual and team work. This approach seeks to help students achieve course objectives while learning how to function in teams. The purpose of the research was to assess the implementation and effectiveness of TBL in English language classes at USM technical training education. Quantitative and qualitative data were collected from teachers and students about their experience through TBL. Research findings show that both teachers and students are satisfied with the method and that students’ engagement and participation in class is higher. Additionally, students score higher on examinations improving academic outcomes. The findings of the research have the potential to guide how TBL could be included in future English language courses.

Keywords: collaborative learning, college education, English language learning, team-based learning

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1533 Production of Buttermilk as a Bio-Active Functional Food by Utilizing Dairy Waste

Authors: Hafsa Tahir, Sanaullah Iqbal

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Glactooligosaccharide (GOS) is a type of prebiotic which is mainly found in human milk. GOS belongs to those bacteria which stimulates the growth of beneficial bacteria in human intestines. The aim of the present study was to develop a value-added product by producing prebiotic (GOS) in buttermilk through trans galactosylation. Buttermilk is considered as an industrial waste which is discarded after the production of butter and cream. It contains protein, minerals, vitamins and a smaller amount of fat. Raw milk was pasteurized at 100º C for butter production and then trans galactosylation process was induced in the butter milk thus obtained to produce prebiotic GOS. Results showed that the enzyme (which was obtained from bacterial strain of Esecrshia coli and has a gene of Lactobacillus reuteri L103) concentration between 400-600µl/5ml can produce GOS in 30 minutes. Chemical analysis and sensory evaluation of plain and GOS containing buttermilk showed no remarkable difference in their composition. Furthermore, the shelf-life study showed that there was non-significant (P>0.05) difference in glass and pouch packaging of buttermilk. Buttermilk in pouch packaging maintained its stability for 6 days without the addition of preservatives. Therefore it is recommended that GOS enriched buttermilk which is generally considered as a processing waste in dairy manufacturing can be turned into a cost-effective nutritional functional food product. This will not only enhance the production efficiency of butter processing but also will create a new market opportunity for dairy manufacturers all over the world.

Keywords: buttermilk, galactooligosaccharide, shelf Life, transgalactosylation

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1532 Hepatological Alterations in Market Gardeners Occupationally Exposed to Pesticides in the Western Highlands of Cameroon

Authors: M. G. Tanga, P. B. Telefo, D. N. Tarla

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Even though the WHO, the EPA and other regulatory bodies have recognized the effects of acute pesticide poisoning little data exists on health effects after long-term low-dose exposures especially in Africa and Cameroon. The aim of this study was to evaluate the impact of pesticides on the hepatic functions of market gardeners in the Western Region of Cameroon by studying some biochemical parameters. Sixty six male market gardeners in Foumbot, Massangam, and Bantoum were interviewed on their health status, habits and pesticide use in agriculture, including the spray frequency, application method, and pesticide dosage. Thirty men with no history of pesticide exposure were recruited as control group. Thereafter, their blood samples were collected for assessment of hepatic function biomarkers (ALT, AST, and albumin). The results showed that 56 pesticides containing 25 active ingredients were currently used by market gardeners enrolled in our study and most of their symptoms (headache, fatigue, skin rashes, eye irritation, and nausea) were related to the use of these chemicals. Compared to the control subjects market gardeners’ ALT levels (32.9 ± 7.19 UL-1 vs. 82.11 ± 35.40 UL-1; P < 0.001) and, AST levels (40.63 ± 6.52 UL-1 vs. 112.11 UL-1 ± 47.15 UL-1; P < 0.001) were significantly increased. These results suggest that liver function tests can be used as biomarkers to indicate toxicity before overt clinical signs occur. The market gardeners’ chronic exposure to pesticides due to poor application measures could lead to hepatic function impairment. Further research on larger scale is needed to confirm these findings and to establish a mechanism of toxicity.

Keywords: biomarkers, liver, pesticides, occupational exposure

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1531 The Effect of Using Emg-based Luna Neurorobotics for Strengthening of Affected Side in Chronic Stroke Patients - Retrospective Study

Authors: Surbhi Kaura, Sachin Kandhari, Shahiduz Zafar

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Chronic stroke, characterized by persistent motor deficits, often necessitates comprehensive rehabilitation interventions to improve functional outcomes and mitigate long-term dependency. Luna neurorobotic devices, integrated with EMG feedback systems, provide an innovative platform for facilitating neuroplasticity and functional improvement in stroke survivors. This retrospective study aims to investigate the impact of EMG-based Luna neurorobotic interventions on the strengthening of the affected side in chronic stroke patients. In rehabilitation, active patient participation significantly activates the sensorimotor network during motor control, unlike passive movement. Stroke is a debilitating condition that, when not effectively treated, can result in significant deficits and lifelong dependency. Common issues like neglecting the use of limbs can lead to weakness in chronic stroke cases. In rehabilitation, active patient participation significantly activates the sensorimotor network during motor control, unlike passive movement. This study aims to assess how electromyographic triggering (EMG-triggered) robotic treatments affect walking, ankle muscle force after an ischemic stroke, and the coactivation of agonist and antagonist muscles, which contributes to neuroplasticity with the assistance of biofeedback using robotics. Methods: The study utilized robotic techniques based on electromyography (EMG) for daily rehabilitation in long-term stroke patients, offering feedback and monitoring progress. Each patient received one session per day for two weeks, with the intervention group undergoing 45 minutes of robot-assisted training and exercise at the hospital, while the control group performed exercises at home. Eight participants with impaired motor function and gait after stroke were involved in the study. EMG-based biofeedback exercises were administered through the LUNA neuro-robotic machine, progressing from trigger and release mode to trigger and hold, and later transitioning to dynamic mode. Assessments were conducted at baseline and after two weeks, including the Timed Up and Go (TUG) test, a 10-meter walk test (10m), Berg Balance Scale (BBG), and gait parameters like cadence, step length, upper limb strength measured by EMG threshold in microvolts, and force in Newton meters. Results: The study utilized a scale to assess motor strength and balance, illustrating the benefits of EMG-biofeedback following LUNA robotic therapy. In the analysis of the left hemiparetic group, an increase in strength post-rehabilitation was observed. The pre-TUG mean value was 72.4, which decreased to 42.4 ± 0.03880133 seconds post-rehabilitation, with a significant difference indicated by a p-value below 0.05, reflecting a reduced task completion time. Similarly, in the force-based task, the pre-knee dynamic force in Newton meters was 18.2NM, which increased to 31.26NM during knee extension post-rehabilitation. The post-student t-test showed a p-value of 0.026, signifying a significant difference. This indicated an increase in the strength of knee extensor muscles after LUNA robotic rehabilitation. Lastly, at baseline, the EMG value for ankle dorsiflexion was 5.11 (µV), which increased to 43.4 ± 0.06 µV post-rehabilitation, signifying an increase in the threshold and the patient's ability to generate more motor units during left ankle dorsiflexion. Conclusion: This study aimed to evaluate the impact of EMG and dynamic force-based rehabilitation devices on walking and strength of the affected side in chronic stroke patients without nominal data comparisons among stroke patients. Additionally, it provides insights into the inclusion of EMG-triggered neurorehabilitation robots in the daily rehabilitation of patients.

Keywords: neurorehabilitation, robotic therapy, stroke, strength, paralysis

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1530 Additional Opportunities of Forensic Medical Identification of Dead Bodies of Unkown Persons

Authors: Saule Mussabekova

Abstract:

A number of chemical elements widely presented in the nature is seldom met in people and vice versa. This is a peculiarity of accumulation of elements in the body, and their selective use regardless of widely changed parameters of external environment. Microelemental identification of human hair and particularly dead body is a new step in the development of modern forensic medicine which needs reliable criteria while identifying the person. In the condition of technology-related pressing of large industrial cities for many years and specific for each region multiple-factor toxic effect from many industrial enterprises it’s important to assess actuality and the role of researches of human hair while assessing degree of deposition with specific pollution. Hair is highly sensitive biological indicator and allows to assess ecological situation, to perform regionalism of large territories of geological and chemical methods. Besides, monitoring of concentrations of chemical elements in the regions of Kazakhstan gives opportunity to use these data while performing forensic medical identification of dead bodies of unknown persons. Methods based on identification of chemical composition of hair with further computer processing allowed to compare received data with average values for the sex, age, and to reveal causally significant deviations. It gives an opportunity preliminary to suppose the region of residence of the person, having concentrated actions of policy for search of people who are unaccounted for. It also allows to perform purposeful legal actions for its further identification having created more optimal and strictly individual scheme of personal identity. Hair is the most suitable material for forensic researches as it has such advances as long term storage properties with no time limitations and specific equipment. Besides, quantitative analysis of micro elements is well correlated with level of pollution of the environment, reflects professional diseases and with pinpoint accuracy helps not only to diagnose region of temporary residence of the person but to establish regions of his migration as well. Peculiarities of elemental composition of human hair have been established regardless of age and sex of persons residing on definite territories of Kazakhstan. Data regarding average content of 29 chemical elements in hair of population in different regions of Kazakhstan have been systemized. Coefficients of concentration of studies elements in hair relative to average values around the region have been calculated for each region. Groups of regions with specific spectrum of elements have been emphasized; these elements are accumulated in hair in quantities exceeding average indexes. Our results have showed significant differences in concentrations of chemical elements for studies groups and showed that population of Kazakhstan is exposed to different toxic substances. It depends on emissions to atmosphere from industrial enterprises dominating in each separate region. Performed researches have showed that obtained elemental composition of human hair residing in different regions of Kazakhstan reflects technogenic spectrum of elements.

Keywords: analysis of elemental composition of hair, forensic medical research of hair, identification of unknown dead bodies, microelements

Procedia PDF Downloads 142
1529 ORR Electrocatalyst for Batteries and Fuel Cells Development with SiO2/Carbon Black Based Composite Nanomaterials

Authors: Maryam Kiani

Abstract:

This study focuses on the development of composite nanomaterials based on SiO2 and carbon black for oxygen reduction reaction (ORR) electrocatalysts in batteries and fuel cells. The aim was to explore the potential of these composite materials as efficient catalysts for ORR, which is a critical process in energy conversion devices. The SiO2/carbon black composite nanomaterials were synthesized using a facile and scalable method. The morphology, structure, and electrochemical properties of the materials were characterized using various techniques, including scanning electron microscopy (SEM), X-ray diffraction (XRD), and electrochemical measurements. The results demonstrated that the incorporation of SiO2 into the carbon black matrix enhanced the ORR performance of the composite material. The composite nanomaterials exhibited improved electrocatalytic activity, enhanced stability, and increased durability compared to pure carbon black. The presence of SiO2 facilitated the formation of active sites, improved electron transfer, and increased the surface area available for ORR. This study contributes to the advancement of battery and fuel cell technology by offering a promising approach for the development of high-performance ORR electrocatalysts. The SiO2/carbon black composite nanomaterials show great potential for improving the efficiency and durability of energy conversion devices, leading to more sustainable and efficient energy solutions.

Keywords: oxygen reduction reaction, batteries, fuel cells, electrrocatalyst

Procedia PDF Downloads 117
1528 Transformation and Integration: Iranian Women Migrants and the Use of Social Media in Australia

Authors: Azadeh Davachi

Abstract:

Although there is a growing interest in Iranian female migration and gender roles, little attention has been paid to how Iranian migrant women in Australia access and sustain social networks, both locally and spatially dispersed over time. Social network theories have much to offer an analysis of migrant’s social ties and interpersonal relationships. Thus, it is important to note that social media are not only new communication channels in a migration network but also that they actively transform the nature of these networks and thereby facilitate migration for migrants. Drawing on that, this article will focus on Iranian women migrants and the use of social media in migration in Australia. Based on the case of main social networks such as Facebook and Instagram; this paper will investigate that how women migrants use these networks to facilitate the process of migration and integration. In addition, with the use of social networks, they could promote their home business and as a result become more engaged economically in Australian society. This paper will focus on three main Iranian pages in Instagram and Facebook, they will contend that compared to men, women are more active in these social networks. Consequently, as this article will discuss with the use of these social media Iranian migrant women can become more engaged and overcome post migration hardships, thus, gender plays a key role in using social media in migrant communities. Based on these findings from these social media pages, this paper will conclude that social media are transforming migration networks and thereby lowering the threshold for migration. It also will be demonstrated that these networks boost Iranian women’s confidence and lead them to become more visible in Iranian migrant communities comparing to men.

Keywords: integration, gender, migration, women migrants

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1527 Lessons Learned in Developing a Clinical Information System and Electronic Health Record (EHR) System That Meet the End User Needs and State of Qatar's Emerging Regulations

Authors: Darshani Premaratne, Afshin Kandampath Puthiyadath

Abstract:

The Government of Qatar is taking active steps in improving quality of health care industry in the state of Qatar. In this initiative development and market introduction of Clinical Information System and Electronic Health Record (EHR) system are proved to be a highly challenging process. Along with an organization specialized on EHR system development and with the blessing of Health Ministry of Qatar the process of introduction of EHR system in Qatar healthcare industry was undertaken. Initially a market survey was carried out to understand the requirements. Secondly, the available government regulations, needs and possible upcoming regulations were carefully studied before deployment of resources for software development. Sufficient flexibility was allowed to cater for both the changes in the market and the regulations. As the first initiative a system that enables integration of referral network where referral clinic and laboratory system for all single doctor (and small scale) clinics was developed. Setting of isolated single doctor clinics all over the state to bring in to an integrated referral network along with a referral hospital need a coherent steering force and a solid top down framework. This paper discusses about the lessons learned in developing, in obtaining approval of the health ministry and in introduction to the industry of the single doctor referral network along with an EHR system. It was concluded that development of this nature required continues balance between the market requirements and upcoming regulations. Further accelerating the development based on the emerging needs, implementation based on the end user needs while tallying with the regulations, diffusion, and uptake of demand-driven and evidence-based products, tools, strategies, and proper utilization of findings were equally found paramount in successful development of end product. Development of full scale Clinical Information System and EHR system are underway based on the lessons learned. The Government of Qatar is taking active steps in improving quality of health care industry in the state of Qatar. In this initiative development and market introduction of Clinical Information System and Electronic Health Record (EHR) system are proved to be a highly challenging process. Along with an organization specialized on EHR system development and with the blessing of Health Ministry of Qatar the process of introduction of EHR system in Qatar healthcare industry was undertaken. Initially a market survey was carried out to understand the requirements. Secondly the available government regulations, needs and possible upcoming regulations were carefully studied before deployment of resources for software development. Sufficient flexibility was allowed to cater for both the changes in the market and the regulations. As the first initiative a system that enables integration of referral network where referral clinic and laboratory system for all single doctor (and small scale) clinics was developed. Setting of isolated single doctor clinics all over the state to bring in to an integrated referral network along with a referral hospital need a coherent steering force and a solid top down framework. This paper discusses about the lessons learned in developing, in obtaining approval of the health ministry and in introduction to the industry of the single doctor referral network along with an EHR system. It was concluded that development of this nature required continues balance between the market requirements and upcoming regulations. Further accelerating the development based on the emerging needs, implementation based on the end user needs while tallying with the regulations, diffusion, and uptake of demand-driven and evidence-based products, tools, strategies, and proper utilization of findings were equally found paramount in successful development of end product. Development of full scale Clinical Information System and EHR system are underway based on the lessons learned.

Keywords: clinical information system, electronic health record, state regulations, integrated referral network of clinics

Procedia PDF Downloads 362
1526 Community Benefitting through Tourism: DASTA-Thailand Model

Authors: Jutamas Wisansing, Thanakarn Vongvisitsin, Udom Hongchatikul

Abstract:

Designated Areas for Sustainable Tourism Administration (DASTA) is a public organization, dedicating to sustainable tourism development in 6 designated areas in Thailand. This paper provides rich reflections from a decade of DASTA, formulating an advanced model to deepen our understanding of 2 key intertwining issues; 1) what are the new landscapes of actors for community based tourism and 2) who are the benefactors and beneficiaries of tourism development within the community? An action research approach was used, enabling the process and evidence-based cases to be better captured. The aim is to build theoretical foundation through 13 communities/cases, which have engaged in community based tourism pilot projects. Drawing from emic and qualitative research, specific and contextual phenomenon provides succinct patterns of ‘Community Benefitting through Tourism (CbtT)’ model. The re-definition of the 2 key issues helps shape the interlinking of actors; practicalities of inclusive tourism and inter-sectoral framework and its value chain will also be set forth. In tourism sector, community members could be active primarily on the supply side as employees, entrepreneurs and local heritage experts. CbtT when well defined stimulates the entire value chain of local economy while promoting social innovation through positive dialogue with wider actors. Collaboration with a new set of actors who are from the tourism-related businesses and non-tourism related businesses create better impacts on mutual benefits.

Keywords: community based tourism, community benefitting through tourism -CbtT DASTA model, sustainable tourism in thailand, value chain and inclusive business

Procedia PDF Downloads 299
1525 21st Century Gunboat Diplomacy and Strategic Sea Areas

Authors: Mustafa Avsever

Abstract:

Throughout history, states have attached great importance to seas in terms of economic and security. Advanced civilizations have always founded in coastal regions. Over time, human being has tended to trade and naturally always aimed get more and more. Seas by covering 71% of the earth, provide the greatest economic opportunities for access to raw material resources and the world market. As a result, seas have become the most important areas of conflict over the course of time. Coastal states, use seas as a tool for defense zone, trade, marine transportation and power transfer, they have acquired colonies overseas and increased their capital, raw materials and labor. Societies, have increased their economic prosperity, though their navies in order to retain their welfare and achieve their foreign policy objectives. Sometimes they have imposed their demands through the use or threat of limited naval force in accordance with their interests that is gunboat diplomacy. Today we can see samples of gunboat diplomacy used in the Eastern Mediterranean, during Ukraine crisis, in dispute between North Korea and South Korea and the ongoing power struggle in Asia-Pacific. Gunboat diplomacy has been and continues to be applied consistently in solving problems by the stronger side of the problem. The purpose of this article is to examine using navy under the gunboat diplomacy as an active instrument of foreign policy and security policy and reveal the strategic sea areas in which gunboat diplomacy is used effectively in the matrix of international politics in the 21st century.

Keywords: gunboat diplomacy, maritime strategy, sea power, strategic sea lands

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1524 The Oppressive Boss and Employees' Authoritarianism: The Relation between Suppression of Voice by Employers and Employees' Preferences for Authoritarian Political Leadership

Authors: Antonia Stanojević, Agnes Akkerman

Abstract:

In contemporary society, economically active people typically spend most of their waking hours doing their job. Having that in mind, this research examines how socialization at the workplace shapes political preferences. Innovatively, it examines, in particular, the possible relationship between employees’ voice suppression by the employer and the formation of their political preferences. Since the employer is perceived as an authority figure, their behavior might induce spillovers to attitudes about political authorities and authoritarian governance. Therefore, a positive effect of suppression of voice by employers on employees' preference for authoritarian governance is expected. Furthermore, this relation is expected to be mediated by two mechanisms: system justification and power distance. Namely, it is expected that suppression of voice would create a power distance organizational climate and increase employees’ acceptance of unequal distribution of power, as well as evoke attempts of oppression rationalization through system justification. The hypotheses will be tested on the data gathered within the first wave of Work and Politics Dataset 2017 (N=6000), which allows for a wide range of demographic and psychological control variables. Although a cross-sectional analysis to be used at this point does not allow for causal inferences, the confirmation of expected relationships would encourage and justify further longitudinal research on the same panel dataset, in order to get a clearer image of the causal relationship between employers' suppression of voice and workers' political preferences.

Keywords: authoritarian values, political preferences, power distance, system justification, voice suppression

Procedia PDF Downloads 269
1523 Genetic Diversity of Mycobacterium bovis and Its Zoonotic Potential in Ethiopia: A Systematic Review

Authors: Begna Tulu, Gobena Ameni

Abstract:

Understanding the types of Mycobacterium bovis (M. bovis) strains circulating in a country and exploring its zoonotic potential has significant contribution in the effort to design control strategies. The main aim of this study was to review and compile the results of studies conducted on M. bovis genotyping and its zoonotic potential of M. bovis in Ethiopia. A systematic search and review of articles published on M. bovis strains in Ethiopia were made. PubMed and Google Scholar databases were considered for the search while the keywords used were 'Mycobacteria,' 'Mycobacterium bovis,' 'Bovine Tuberculosis' and 'Ethiopia.' Fourteen studies were considered in this review and a total of 31 distinct strains of M. bovis (N=211) were obtained; the most dominant strains were SB0133 (N=62, 29.4%), SB1176 (N=61, 28.9%), and followed by SB0134 and SB1476 each (N=18, 8.5%). The clustering rate of M. bovis strains was found to be 42.0%. On the other hand, 6 strains of M. bovis were reported from human namely; SB0665 (N=4), SB0303 (N=2), SB0982 (N=2), SB0133 (N=1), SB1176 (N=1), and 1 new strain. Similarly, a total of 8 strains (N=13) of M. tuberculosis bacteria were also identified from animal subjects; namely SIT149 (N=3), SIT1 (N=2), SIT1688 (n=2), SIT262 (N=2), SIT53 (N=1), SIT59 (N=1), and one new-Ethiopian strain. The result showed that the genetic diversity of M. bovis strains reported from Ethiopia are less diversified and highly clustered. And also the result underlines that there is an ongoing active transmission of M. bovis and M. tuberculosis between human and animals in Ethiopia because a significant number strains of both type of bacteria were reported from human and animals.

Keywords: mycobacterium bovis, Mycobacterium tuberculosis, zoonotic potential, genetic diversity, Ethiopia

Procedia PDF Downloads 139
1522 Characterization the Internal Corrosion Behavior by Using Natural Inhibitor in Crude Oil of Low Carbon Steel Pipeline

Authors: Iman Adnan Annon, Kadhim F. Alsultan

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This study investigate the internal corrosion of low carbon steel pipelines in the crude oil, as well as prepare and use natural and locally available plant as a natural corrosion inhibiter, the nature extraction achieved by two types of solvents in order to show the solvent effect on inhibition process, the first being distilled water and the second is diethyl ether. FT-IR spectra and using a chemical reagents achieved to detection the presence of many active groups and the presence of tannins, phenols, and alkaloids in the natural extraction. Some experiments were achieved to estimate the performance of a new inhibitor, one of these tests include corrosion measurement by simple immersion in crude oil within and without inhibitors which added in different amounts 30,40,50and 60 ppm at tow temperature 300 and 323k, where the best inhibition efficiencies which get when added the inhibitors in a critical amounts or closest to it, since for the aqueous extract (EB-A) the inhibition efficiency reached (94.4) and (86.71)% at 300 and 323k respectively, and for diethyl ether extract (EB-D) reached (82.87) and (84.6)% at 300 and 323k respectively. Optical microscopy examination have been conducted to evaluate the corrosion nature where it show a clear difference in the topography of the immersed samples surface after add the inhibitors at two temperatures. The results show that the new corrosion inhibitor is not only equivalent to a chemical inhibitor but has greatly improvement properties such as: high efficiency, low cost, non-toxic, easily to produce, and nonpolluting as compared with chemical inhibitor.

Keywords: corrosion in pipeline, inhibitors, crude oil, carbon steel, types of solvent

Procedia PDF Downloads 140
1521 Investigation of Crack Formation in Ordinary Reinforced Concrete Beams and in Beams Strengthened with Carbon Fiber Sheet: Theory and Experiment

Authors: Anton A. Bykov, Irina O. Glot, Igor N. Shardakov, Alexey P. Shestakov

Abstract:

This paper presents the results of experimental and theoretical investigations of the mechanisms of crack formation in reinforced concrete beams subjected to quasi-static bending. The boundary-value problem has been formulated in the framework of brittle fracture mechanics and has been solved by using the finite-element method. Numerical simulation of the vibrations of an uncracked beam and a beam with cracks of different size serves to determine the pattern of changes in the spectrum of eigenfrequencies observed during crack evolution. Experiments were performed on the sequential quasistatic four-point bending of the beam leading to the formation of cracks in concrete. At each loading stage, the beam was subjected to an impulse load to induce vibrations. Two stages of cracking were detected. At the first stage the conservative process of deformation is realized. The second stage is an active cracking, which is marked by a sharp change in eingenfrequencies. The boundary of a transition from one stage to another is well registered. The vibration behavior was examined for the beams strengthened by carbon-fiber sheet before loading and at the intermediate stage of loading after the grouting of initial cracks. The obtained results show that the vibrodiagnostic approach is an effective tool for monitoring of cracking and for assessing the quality of measures aimed at strengthening concrete structures.

Keywords: crack formation, experiment, mathematical modeling, reinforced concrete, vibrodiagnostics

Procedia PDF Downloads 306
1520 Preliminary Evaluation of Echinacea Species by UV-VIS Spectroscopy Fingerprinting of Phenolic Compounds

Authors: Elena Ionescu, Elena Iacob, Marie-Louise Ionescu, Carmen Elena Tebrencu, Oana Teodora Ciuperca

Abstract:

Echinacea species (Asteraceae) has received a global attention because it is widely used for treatment of cold, flu and upper respiratory tract infections. Echinacea species contain a great variety of chemical components that contribute to their activity. The most important components responsible for the biological activity are those with high molecular-weight such as polysaccharides, polyacetylenes, highly unsaturated alkamides and caffeic acid derivatives. The principal factors that may influence the chemical composition of Echinacea include the species and the part of plant used (aerial parts or roots ). In recent years the market for Echinacea has grown rapidly and also the cases of adultery/replacement especially for Echinacea root. The identification of presence or absence of same biomarkers provide information for safe use of Echinacea species in food supplements industry. The aim of the study was the preliminary evaluation and fingerprinting by UV-VISIBLE spectroscopy of biomarkers in terms of content in phenolic derivatives of some Echinacea species (E. purpurea, E. angustifolia and E. pallida) for identification and authentication of the species. The steps of the study were: (1) samples (extracts) preparation from Echinacea species (non-hydrolyzed and hydrolyzed ethanol extracts); (2) samples preparation of reference substances (polyphenol acids: caftaric acid, caffeic acid, chlorogenic acid, ferulic acid; flavonoids: rutoside, hyperoside, isoquercitrin and their aglycones: quercitri, quercetol, luteolin, kaempferol and apigenin); (3) identification of specific absorption at wavelengths between 700-200 nm; (4) identify the phenolic compounds from Echinacea species based on spectral characteristics and the specific absorption; each class of compounds corresponds to a maximum absorption in the UV spectrum. The phytochemical compounds were identified at specific wavelengths between 700-200 nm. The absorption intensities were measured. The obtained results proved that ethanolic extract showed absorption peaks attributed to: phenolic compounds (free phenolic acids and phenolic acids derivatives) registrated between 220-280 nm, unsymmetrical chemical structure compounds (caffeic acid, chlorogenic acid, ferulic acid) with maximum absorption peak and absorption "shoulder" that may be due to substitution of hydroxyl or methoxy group, flavonoid compounds (in free form or glycosides) between 330-360 nm, due to the double bond in position 2,3 and carbonyl group in position 4 flavonols. UV spectra showed two major peaks of absorption (quercetin glycoside, rutin, etc.). The results obtained by UV-VIS spectroscopy has revealed the presence of phenolic derivatives such as cicoric acid (240 nm), caftaric acid (329 nm), caffeic acid (240 nm), rutoside (205 nm), quercetin (255 nm), luteolin (235 nm) in all three species of Echinacea. The echinacoside is absent. This profile mentioned above and the absence of phenolic compound echinacoside leads to the conclusion that species harvested as Echinacea angustifolia and Echinacea pallida are Echinacea purpurea also; It can be said that preliminary fingerprinting of Echinacea species through correspondence with the phenolic derivatives profile can be achieved by UV-VIS spectroscopic investigation, which is an adequate technique for preliminary identification and authentication of Echinacea in medicinal herbs.

Keywords: Echinacea species, Fingerprinting, Phenolic compounds, UV-VIS spectroscopy

Procedia PDF Downloads 261