Search results for: Direct Instructional Technique
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 9985

Search results for: Direct Instructional Technique

8995 Impact of Zn/Cr Ratio on ZnCrOx-SAPO-34 Bifunctional Catalyst for Direct Conversion of Syngas to Light Olefins

Authors: Yuxuan Huang, Weixin Qian, Hongfang Ma, Haitao Zhang, Weiyong Ying

Abstract:

Light olefins are important building blocks for chemical industry. Direct conversion of syngas to light olefins has been investigated for decades. Meanwhile, the limit for light olefins selectivity described by Anderson-Schulz-Flory (ASF) distribution model is still a great challenge to conventional Fischer-Tropsch synthesis. The emerging strategy called oxide-zeolite concept (OX-ZEO) is a promising way to get rid of this limit. ZnCrOx was prepared by co-precipitation method and (NH4)2CO3 was used as precipitant. SAPO-34 was prepared by hydrothermal synthesis, and Tetraethylammonium hydroxide (TEAOH) was used as template, while silica sol, pseudo-boehmite, and phosphoric acid were Al, Si and P source, respectively. The bifunctional catalyst was prepared by mechanical mixing of ZnCrOx and SAPO-34. Catalytic reactions were carried out under H2/CO=2, 380 ℃, 1 MPa and 6000 mL·gcat-1·h-1 in a fixed-bed reactor with a quartz lining. Catalysts were characterized by XRD, N2 adsorption-desorption, NH3-TPD, H2-TPR, and CO-TPD. The addition of Al as structure promoter enhances CO conversion and selectivity to light olefins. Zn/Cr ratio, which decides the active component content and chemisorption property of the catalyst, influences CO conversion and selectivity to light olefins at the same time. C2-4= distribution of 86% among hydrocarbons at CO conversion of 14% was reached when Zn/Cr=1.5.

Keywords: light olefins, OX-ZEO, Syngas, ZnCrOₓ

Procedia PDF Downloads 180
8994 Growth Curves Genetic Analysis of Native South Caspian Sea Poultry Using Bayesian Statistics

Authors: Jamal Fayazi, Farhad Anoosheh, Mohammad R. Ghorbani, Ali R. Paydar

Abstract:

In this study, to determine the best non-linear regression model describing the growth curve of native poultry, 9657 chicks of generations 18, 19, and 20 raised in Mazandaran breeding center were used. Fowls and roosters of this center distributed in south of Caspian Sea region. To estimate the genetic variability of none linear regression parameter of growth traits, a Gibbs sampling of Bayesian analysis was used. The average body weight traits in the first day (BW1), eighth week (BW8) and twelfth week (BW12) were respectively estimated as 36.05, 763.03, and 1194.98 grams. Based on the coefficient of determination, mean squares of error and Akaike information criteria, Gompertz model was selected as the best growth descriptive function. In Gompertz model, the estimated values for the parameters of maturity weight (A), integration constant (B) and maturity rate (K) were estimated to be 1734.4, 3.986, and 0.282, respectively. The direct heritability of BW1, BW8 and BW12 were respectively reported to be as 0.378, 0.3709, 0.316, 0.389, 0.43, 0.09 and 0.07. With regard to estimated parameters, the results of this study indicated that there is a possibility to improve some property of growth curve using appropriate selection programs.

Keywords: direct heritability, Gompertz, growth traits, maturity weight, native poultry

Procedia PDF Downloads 264
8993 Synthesis of Y2O3 Films by Spray Coating with Milled EDTA ・Y・H Complexes

Authors: Keiji Komatsu,Tetsuo Sekiya, Ayumu Toyama, Atsushi Nakamura, Ikumi Toda, Shigeo Ohshio, Hiroyuki Muramatsu, Hidetoshi Saitoh

Abstract:

Yttrium oxide (Y2O3) films have been successfully deposited with yttrium-ethylenediaminetetraacetic acid (EDTA・Y・H) complexes prepared by various milling techniques. The effects of the properties of the EDTA・Y・H complex on the properties of the deposited Y2O3 films have been analyzed. Seven different types of the raw EDTA・Y・H complexes were prepared by various commercial milling techniques such as ball milling, hammer milling, commercial milling, and mortar milling. The milled EDTA・Y・H complexes exhibited various particle sizes and distributions, depending on the milling method. Furthermore, we analyzed the crystal structure, morphology and elemental distribution profile of the metal oxide films deposited on stainless steel substrate with the milled EDTA・Y・H complexes. Depending on the milling technique, the flow properties of the raw powders differed. The X-ray diffraction pattern of all the samples revealed the formation of Y2O3 crystalline phase, irrespective of the milling technique. Of all the different milling techniques, the hammer milling technique is considered suitable for fabricating dense Y2O3 films.

Keywords: powder sizes and distributions, flame spray coating techniques, Yttrium oxide

Procedia PDF Downloads 395
8992 Focalization Used as a Narrative Strategy Mirroring Fadia Faqir’s Ideology in Pillars of Salt 1996

Authors: Malika Hammouche

Abstract:

The novel Pillars of Salt, written by Fadia Faqir in 1996, is a good example where storytelling is utilized as a traditional material to underline the author’s womanist ideology. A study of narrative could be fruitfully combined with that of ideology in this case. This combination could be demonstrated through the narrative technique used by Fadia Faqir in Pillars of Salt (1996), reflecting her anti-colonial ideology. The first step of this work will highlight the storyteller’s narrative in the novel representing, on the one hand, the imperial voice, and on the other exoticism and orientalism. The second step will demonstrate how Faqir’s narrative technique uses focalization as a narratological tool to negotiate her space. Faqir gives a voice to the female protagonist of the novel within the androcentric bias of Arab narrative theory to point to and amend the orientalist discourse typical to colonial literature. The orientalist discourse is represented through the voice of the storyteller in the novel. The juxtaposition of the storyteller’s and the female protagonist narratives is borrowed from the Arab literary background. It is a postcolonial counter-discursive strategy used by the author as a traditional material to underline her Arabo Islamic Womanist ideology in this novel.

Keywords: Arabo Islamic womanism, focalization, ideology, narrative technique, orientalist

Procedia PDF Downloads 240
8991 Investment Development Path and Motivations for Foreign Direct Investment in Georgia

Authors: Vakhtang Charaia, Mariam Lashkhi

Abstract:

Foreign direct investment (FDI) plays a vital role in global business. It provides firms with new markets and advertising channels, cheaper production facilities, admission to new technology, products, skills and financing. FDI can provide a recipient country/company with a source of new technologies, capital, practice, products, management skills, and as such can be a powerful drive for economic development. It is one of the key elements of stable economic development in many countries, especially in developing ones. Therefore the size of FDI inflow is one of the most crustal factors for economic perfection in small economy countries (like, Georgia), while most of developed ones are net exporters of FDI. Since, FDI provides firms with new markets; admission to new technologies, products and management skills; marketing channels; cheaper production facilities, and financing opportunities. It plays a significant role in Georgian economic development. Increasing FDI inflows from all over the world to Georgia in last decade was achieved with the outstanding reforms managed by the Georgian government. However, such important phenomenon as world financial crisis and Georgian-Russian war put its consequence on the over amount of FDI inflow in Georgia in the last years. It is important to mention that the biggest investor region for Georgia is EU, which is interested in Georgia not only from the economic points of view but from political. The case studies from main EU investor countries show that Georgia has a big potential of investment in different areas, such as; financial sector, energy, construction, tourism industry, transport and communications. Moreover, signing of Association Agreement between Georgia and EU will further boost all the fields of economy in Georgia in both short and long terms. It will attract more investments from different countries and especially from EU. The last, but not least important issue is the calculation of annual FDI inflow to Georgia, which it is calculated differently by different organizations, based on different methodologies, but what is more important is that all of them show significant increase of FDI in last decade, which gives a positive signal to investors and underlines necessity of further improvement of investment climate in the same direction.

Keywords: foreign direct investment (FDI), Georgia, investment development path, investment climate

Procedia PDF Downloads 280
8990 Decision Support System for Solving Multi-Objective Routing Problem

Authors: Ismail El Gayar, Ossama Ismail, Yousri El Gamal

Abstract:

This paper presented a technique to solve one of the transportation problems that faces us in real life which is the Bus Scheduling Problem. Most of the countries using buses in schools, companies and traveling offices as an example to transfer multiple passengers from many places to specific place and vice versa. This transferring process can cost time and money, so we build a decision support system that can solve this problem. In this paper, a genetic algorithm with the shortest path technique is used to generate a competitive solution to other well-known techniques. It also presents a comparison between our solution and other solutions for this problem.

Keywords: bus scheduling problem, decision support system, genetic algorithm, shortest path

Procedia PDF Downloads 414
8989 Teacher Candidates' Beliefs About Inclusive Teaching Practices

Authors: Charlotte Brenner

Abstract:

Teachers’ beleifs about inclusion are foundational to their implementation of inclusive teaching practices. Utilizing a longitudinal design and multiple case study methodology, this study investigates how teacher candidates’ instructional and practicum experiences shape their beliefs about inclusion in one teacher education program located in western Canada (N=20). Interview questions were developed through the lens of self-determinaiton theory and theory about teachers’ beleifs and inclusion. Preliminary thematic ananysis indicates that a 36-hour course focused on diversity and inclusion supports teacher candiates to deepen their understandings of: the need for inclusion in classrooms and strategies to promote inclusion. Furthermore, teacher candiates identified course components that fostered their developing understandings of inclusion. Future data will examine the stability of teacher candidates’ beliefs about inclusion and their implementation of inclusive teaching strategies throughout their practicum experiences.

Keywords: teacher candidates, inclusion, teacher education programs, beliefs

Procedia PDF Downloads 88
8988 A Brief Narrative Intervention to Improve Well-being and Relational Ethics in Couples: A Mixed-Method Case Study

Authors: Kevser Cakmak, Adrián Montesano, Lourdes Artigas, Marta Salla, Clara Mateu

Abstract:

The main objective of this research is to explore the relational letter writing technique as an intervention in couple therapy for reconnecting couples with their values and ethical preferences. This is a recently developed therapeutic tool within the framework of Narrative Therapy that consists of two interviews and a letter writing task, in which a meta-conversation between the relationship itself, the couple members, and the therapists is fostered. Although this specific therapeutic technique can be used within the therapy process, in this case study, it is used as a brief stand-alone narrative intervention for a middle age heterosexual couple breast cancer survivor. Couple’s relational and personal wellbeing was monitored before, during, and after the intervention by means of the dyadic adjustment and the clinical outcomes in routine evaluation-outcome measure, respectively. The couple showed a significant improvement after the intervention in both levels. The content of the letter writing exercises was qualitatively analysed to explore the reconstruction of their ethical values. Results from both methods are integrated in order to get an in-depth perspective of the newly developed tool. The potential of the letter writing technique as stand-alone and as adjunct brief intervention is discussed.

Keywords: couple therapy, narrative therapy, psychotherapy tool, relational letter writing

Procedia PDF Downloads 134
8987 Evaluation of the Antibacterial Effects of Turmeric Oleoresin, Capsicum Oleoresin and Garlic Essential Oil against Salmonella enterica Typhimurium

Authors: Jun Hyung Lee, Robin B. Guevarra, Jin Ho Cho, Bo-Ra Kim, Jiwon Shin, Doo Wan Kim, Young Hwa Kim, Minho Song, Hyeun Bum Kim

Abstract:

Salmonella is one of the most important swine pathogens, causing acute or chronic digestive diseases, such as enteritis. The acute form of enteritis is common in young pigs of 2-4 months of age. Salmonellosis in swine causes a huge economic burden to swine industry by reducing production. Therefore, it is necessary that swine industries should strive to decrease Salmonellosis in pigs in order to reduce economic losses. Thus, we tested three types of natural plant extracts(PEs) to evaluate antibacterial effects against Salmonella enterica Typhimurium isolated from the piglet with Salmonellosis. Three PEs including turmeric oleoresin (containing curcumin 79 to 85%), capsicum oleoresin (containing capsaicin 40%-40.1%), and garlic essential oil (100% natural garlic) were tested using the direct contact agar diffusion test, minimum inhibitory concentration test, growth curve assay, and heat stability test. The tests were conducted with PEs at each concentration of 2.5%, 5%, and 10%. For the heat stability test, PEs with 10% concentration were incubated at each 4, 20, 40, 60, 80, and 100 °C for 1 hour; then the direct contact agar diffusion test was used. For the positive and negative controls, 0.5N HCl and 1XPBS were used. All the experiments were duplicated. In the direct contact agar diffusion test, garlic essential oil with 2.5%, 5%, and 10% concentration showed inhibit zones of 1.5cm, 2.7cm, and 2.8cm diameters compared to that of 3.5cm diameter for 0.5N HCl. The minimum inhibited concentration of garlic essential oil was 2.5%. Growth curve assay showed that the garlic essential oil was able to inhibit Salmonella growth significantly after 4hours. The garlic essential oil retained the ability to inhibit Salmonella growth after heat treatment at each temperature. However, turmeric and capsicum oleoresins were not able to significantly inhibit Salmonella growth by all the tests. Even though further in-vivo tests will be needed to verify effects of garlic essential oil for the Salmonellosis prevention for piglets, our results showed that the garlic essential oil could be used as a potential natural agent to prevent Salmonellosis in swine.

Keywords: garlic essential oil, pig, salmonellosis, Salmonella enterica

Procedia PDF Downloads 173
8986 Evaluation of Soil Stiffness and Strength for Quality Control of Compacted Earthwork

Authors: A. Sawangsuriya, T. B. Edil

Abstract:

Microstructure and fabric of soils play an important role on structural properties e.g. stiffness and strength of compacted earthwork. Traditional quality control monitoring based on moisture-density tests neither reflects the variability of soil microstructure nor provides a direct assessment of structural property, which is the ultimate objective of the earthwork quality control. Since stiffness and strength are sensitive to soil microstructure and fabric, any independent test methods that provide simple, rapid, and direct measurement of stiffness and strength are anticipated to provide an effective assessment of compacted earthen materials’ uniformity. In this study, the soil stiffness gauge (SSG) and the dynamic cone penetrometer (DCP) were respectively utilized to measure and monitor the stiffness and strength in companion with traditional moisture-density measurements of various earthen materials used in Thailand road construction projects. The practical earthwork quality control criteria are presented herein in order to assure proper earthwork quality control and uniform structural property of compacted earthworks.

Keywords: dynamic cone penetrometer, moisture content, quality control, relative compaction, soil stiffness gauge, structural properties

Procedia PDF Downloads 360
8985 Load Forecasting Using Neural Network Integrated with Economic Dispatch Problem

Authors: Mariyam Arif, Ye Liu, Israr Ul Haq, Ahsan Ashfaq

Abstract:

High cost of fossil fuels and intensifying installations of alternate energy generation sources are intimidating main challenges in power systems. Making accurate load forecasting an important and challenging task for optimal energy planning and management at both distribution and generation side. There are many techniques to forecast load but each technique comes with its own limitation and requires data to accurately predict the forecast load. Artificial Neural Network (ANN) is one such technique to efficiently forecast the load. Comparison between two different ranges of input datasets has been applied to dynamic ANN technique using MATLAB Neural Network Toolbox. It has been observed that selection of input data on training of a network has significant effects on forecasted results. Day-wise input data forecasted the load accurately as compared to year-wise input data. The forecasted load is then distributed among the six generators by using the linear programming to get the optimal point of generation. The algorithm is then verified by comparing the results of each generator with their respective generation limits.

Keywords: artificial neural networks, demand-side management, economic dispatch, linear programming, power generation dispatch

Procedia PDF Downloads 189
8984 Adaptive Beamforming with Steering Error and Mutual Coupling between Antenna Sensors

Authors: Ju-Hong Lee, Ching-Wei Liao

Abstract:

Owing to close antenna spacing between antenna sensors within a compact space, a part of data in one antenna sensor would outflow to other antenna sensors when the antenna sensors in an antenna array operate simultaneously. This phenomenon is called mutual coupling effect (MCE). It has been shown that the performance of antenna array systems can be degraded when the antenna sensors are in close proximity. Especially, in a systems equipped with massive antenna sensors, the degradation of beamforming performance due to the MCE is significantly inevitable. Moreover, it has been shown that even a small angle error between the true direction angle of the desired signal and the steering angle deteriorates the effectiveness of an array beamforming system. However, the true direction vector of the desired signal may not be exactly known in some applications, e.g., the application in land mobile-cellular wireless systems. Therefore, it is worth developing robust techniques to deal with the problem due to the MCE and steering angle error for array beamforming systems. In this paper, we present an efficient technique for performing adaptive beamforming with robust capabilities against the MCE and the steering angle error. Only the data vector received by an antenna array is required by the proposed technique. By using the received array data vector, a correlation matrix is constructed to replace the original correlation matrix associated with the received array data vector. Then, the mutual coupling matrix due to the MCE on the antenna array is estimated through a recursive algorithm. An appropriate estimate of the direction angle of the desired signal can also be obtained during the recursive process. Based on the estimated mutual coupling matrix, the estimated direction angle, and the reconstructed correlation matrix, the proposed technique can effectively cure the performance degradation due to steering angle error and MCE. The novelty of the proposed technique is that the implementation procedure is very simple and the resulting adaptive beamforming performance is satisfactory. Simulation results show that the proposed technique provides much better beamforming performance without requiring complicated complexity as compared with the existing robust techniques.

Keywords: adaptive beamforming, mutual coupling effect, recursive algorithm, steering angle error

Procedia PDF Downloads 321
8983 Evaluation of the Antibacterial Effects of Turmeric Oleoresin, Capsicum Oleoresin and Garlic Essential Oil against Shiga Toxin-Producing Escherichia coli

Authors: Jun Hyung Lee, Robin B. Guevarra, Jin Ho Cho, Bo-Ra Kim, Jiwon Shin, Doo Wan Kim, Young Hwa Kim, Minho Song, Hyeun Bum Kim

Abstract:

Colibacillosis is one of the major health problems in young piglets ultimately resulting in their death, and it is common especially in young piglets. For the swine industry, colibacillosis is one of the important economic burdens. Therefore, it is necessary for the swine industries to prevent Colibacillosis in piglets in order to reduce economic losses. Thus, we tested three types of natural plant extracts (PEs) to evaluate antibacterial effects against Shiga toxin-producing Escherichia coli (STEC) isolated from the piglet. Three PEs including turmeric oleoresin (containing curcumin 79 to 85%), capsicum oleoresin (containing capsaicin 40%-40.1%), and garlic essential oil (100% natural garlic) were tested using the direct contact agar diffusion test, minimum inhibitory concentration test, growth curve assay, and heat stability test. The tests were conducted with PEs at each concentration of 2.5%, 5%, and 10%. For the heat stability test, PEs with 10% concentration were incubated at each 4, 20, 40, 60, 80, and 100 °C for 1 hour, then the direct contact agar diffusion test was used. For the positive and negative controls, 0.5N HCl and 1XPBS were used. All the experiments were duplicated. In the direct contact agar diffusion test, garlic essential oil with 2.5%, 5%, and 10% concentration showed inhibit zones of 1.1cm, 3.0cm, and 3.6 cm in diameters compared to that of 3.5cm diameter for 0.5N HCl. The minimum inhibited concentration of garlic essential oil was 2.5%. Growth curve assay showed that the garlic essential oil was able to inhibit STEC growth significantly after 4 hours. The garlic essential oil retained the ability to inhibit STEC growth after heat treatment at each temperature. However, turmeric and capsicum oleoresins were not able to significantly inhibit STEC growth by all the tests. Even though further tests using the piglets will be required to evaluate effects of garlic essential oil for the Colibacillosis prevention for piglets, our results showed that the garlic essential oil could be used as a potential natural agent to prevent Colibacillosis in swine.

Keywords: garlic essential oil, pig, Colibacillosis, Escherichia coli

Procedia PDF Downloads 258
8982 Use of Artificial Intelligence in Teaching Practices: A Meta-Analysis

Authors: Azmat Farooq Ahmad Khurram, Sadaf Aslam

Abstract:

This meta-analysis systematically examines the use of artificial intelligence (AI) in instructional methods across diverse educational settings through a thorough analysis of empirical research encompassing various disciplines, educational levels, and regions. This study aims to assess the effects of AI integration on teaching methodologies, classroom dynamics, teachers' roles, and student engagement. Various research methods were used to gather data, including literature reviews, surveys, interviews, and focus group discussions. Findings indicate paradigm shifts in teaching and education, identify emerging trends, practices, and the application of artificial intelligence in learning, and provide educators, policymakers, and stakeholders with guidelines and recommendations for effectively integrating AI in educational contexts. The study concludes by suggesting future research directions and practical considerations for maximizing AI's positive influence on pedagogical practices.

Keywords: artificial intelligence, teaching practices, meta-analysis, teaching-learning

Procedia PDF Downloads 77
8981 Multi-Objective Optimization of Electric Discharge Machining for Inconel 718

Authors: Pushpendra S. Bharti, S. Maheshwari

Abstract:

Electric discharge machining (EDM) is one of the most widely used non-conventional manufacturing process to shape difficult-to-cut materials. The process yield, in terms of material removal rate, surface roughness and tool wear rate, of EDM may considerably be improved by selecting the optimal combination(s) of process parameters. This paper employs Multi-response signal-to-noise (MRSN) ratio technique to find the optimal combination(s) of the process parameters during EDM of Inconel 718. Three cases v.i.z. high cutting efficiency, high surface finish, and normal machining have been taken and the optimal combinations of input parameters have been obtained for each case. Analysis of variance (ANOVA) has been employed to find the dominant parameter(s) in all three cases. The experimental verification of the obtained results has also been made. MRSN ratio technique found to be a simple and effective multi-objective optimization technique.

Keywords: electric discharge machining, material removal rate, surface roughness, too wear rate, multi-response signal-to-noise ratio, multi response signal-to-noise ratio, optimization

Procedia PDF Downloads 354
8980 Experimental Investigation of Hybrid Rocket Motor: Ignition, Throttling and Re-Ignition Phenomena

Authors: A. El-S. Makled, M. K. Al-Tamimi

Abstract:

Ignition phenomena are of great interest area over the past many years, and it has a direct impact on many propulsion and combustion applications. The direct goal of the paper is to realize and evaluate a functioning ignition method, shut-off, throttling and re-start operations for the hybrid rocket motor. A small-scale hybrid rocket motor (SSHRM) is designed, manufactured, demonstrated at various operating conditions and finally equipped for laboratory firing tests with high level of safety. Various solid fuel grains as Polymethyle-methacrylate (PMMA) and Polyethylene (PE) are selected, and it is decided to use the commercial gaseous oxygen (GO2) for its availability and low cost. Examine different types of ignition methods, pyrotechnic charge, fuse wire, heat wire and finally hot oxidizer method by using the heat exchanger, which are proposed as very safe ignition methods. Finally; recognize phenomena of throttling and re-start operations. Ignition by hot GO2 impingement is proved to be a very attractive ignition method for laboratory SSHRM, for its high safety, reliability and acceptable delay time. Finally; the throttling and re-start operations are demonstrated several times and can be carried out more easily with hot air ignition method.

Keywords: hybrid rocket motor, ignition system, re-start phenomena, throttling

Procedia PDF Downloads 301
8979 Preliminary Conceptions of 3D Prototyping Model to Experimental Investigation in Hypersonic Shock Tunnels

Authors: Thiago Victor Cordeiro Marcos, Joao Felipe de Araujo Martos, Ronaldo de Lima Cardoso, David Romanelli Pinto, Paulo Gilberto de Paula Toro, Israel da Silveira Rego, Antonio Carlos de Oliveira

Abstract:

Currently, the use of 3D rapid prototyping, also known as 3D printing, has been investigated by some universities around the world as an innovative technique, fast, flexible and cheap for a direct plastic models manufacturing that are lighter and with complex geometries to be tested for hypersonic shock tunnel. Initially, the purpose is integrated prototyped parts with metal models that actually are manufactured through of the conventional machining and hereafter replace them with completely prototyped models. The mechanical design models to be tested in hypersonic shock tunnel are based on conventional manufacturing processes, therefore are limited forms and standard geometries. The use of 3D rapid prototyping offers a range of options that enables geometries innovation and ways to be used for the design new models. The conception and project of a prototyped model for hypersonic shock tunnel should be rethought and adapted when comparing the conventional manufacturing processes, in order to fully exploit the creativity and flexibility that are allowed by the 3D prototyping process. The objective of this paper is to compare the conception and project of a 3D rapid prototyping model and a conventional machining model, while showing the advantages and disadvantages of each process and the benefits that 3D prototyping can bring to the manufacture of models to be tested in hypersonic shock tunnel.

Keywords: 3D printing, 3D prototyping, experimental research, hypersonic shock tunnel

Procedia PDF Downloads 469
8978 Biofouling Control during the Wastewater Treatment in Self-Support Carbon Nanotubes Membrane: Role of Low Voltage Electric Potential

Authors: Chidambaram Thamaraiselvan, Carlos Dosoretz

Abstract:

This work will explore the influence of low voltage electric field, both alternating (AC) and direct (DC) currents, on biofouling control to highly electrically conductive self-supporting carbon nanotubes (CNT) membranes at conditions which encourage bacterial growth. A mutant strain of Pseudomonas putida S12 was used a model bacterium. The antibiofouling studies were performed with flow-through mode connecting an electric circuit in resistive mode. Major emphasis was placed on AC due to its ability of repulsing and inactivating bacteria. The observations indicate that an AC potential >1500 mV, 1 kHz frequency, 100 Ω external resistance on ground side and pulse wave above the offset (+0.45) almost completely prevented attachment of bacteria (>98.5%) and bacterial inactivation (95.3±2.5%). Findings suggest that at the conditions applied, direct electron transfer might be dominant in a decrease of cell viability. AC resulted more effective than DC, both in terms of biofouling reduction compared to cathodic DC and in terms of cell inactivation compared to anodic DC. This electrically polarized CNT membranes offer a viable antibiofouling strategy to hinder biofouling and simplify membrane care during filtration.

Keywords: bacterial attachment, biofouling control, low electric potential, water treatment

Procedia PDF Downloads 270
8977 Teaching for Change: Instructional Support in a Bilingual Setting

Authors: S. J. Hachar

Abstract:

The goal of this paper is to provide educators an overview of international practices supporting young learners, arming us with adequate information to lead effective change. We will report on research and observations of Service Learning Projects conducted by one South Texas University. The intent of the paper is also to provide readers an overview of service learning in the preparation of teacher candidates pursuing a Bachelor of Science in Elementary Education. The objective of noting the efficiency and effectiveness of programs leading to literacy and oral fluency in a native language and second language will be discussed. This paper also highlights experiential learning for academic credit that combines community service with student learning. Six weeks of visits to a variety of community sites, making personal observations with faculty members, conducting extensive interviews with parents and key personnel at all sites will be discussed. The culminating Service Learning Expo will be reported as well.

Keywords: elementary education, junior achievement, service learning

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8976 Studies On Triazole Resistant Candida Albicans Expressing ERG11 Gene Among Adult Females In Abakaliki; Nigeria

Authors: Agumah N. B. Orji, M. U., Oru C. M., Ugbo, E. N., Onwuliri E. A Nwakaeze, E. A.,

Abstract:

ERG11 gene has been reported to be one of the genes whose expression is responsible for resistance of Candida to various triazole drugs, which are first line treatment for candidiasis. This study was carried out to determine the prevalence of Triazole (Fluconazole and voriconazole) resistant Candida albicans expressing ERG11 gene from adult females in Abakaliki. Urine and vaginal swab samples were randomly collected from volunteers after obtaining their consent to participate in the study. A total of 565 adult females participated in the study. A total of 340 urine specimens and 288 vaginal swab specimens were collected. Direct wet mount technique, as well as culture in Trichomonas broth, were used to examine the urine and vaginal swab specimens for the presence of motile Trichomonads. The Trichomonas broth used was selective for both T. vaginalis and C. albicans. Broths that yielded budding yeast cells after microscopy were subcultured on to Sabouraud dextrose agar, after which Germ tube test was carried out to confirm the presence of C. albicans. Biochemical tests, including carbohydrate fermentation and urease utilization, were also performed. Antibiogram of C. albicans isolates obtained from this study was carried out using commercially available azole drugs. Fluconazole and voriconazole were selected as Triazole drugs used for this study. Nystatin was used as a tangential control. An MIC test was carried out with E-strips on some of the resistant C. albicans isolates A total of 6 isolates that resisted all the azole drugs were selected and screened for the presence of ERG11 gene using Reverse transcriptase polymerase chain reaction technique. The total prevalence recorded for C. albicans was 13.0%. Frequency was statistically higher in Pregnant (7.96%) than non pregnant (5.09%) volunteers (X2=0.94 at P=0.05). With respect to clinical samples, frequency was higher in vaginal swabs samples (7.96%) than Urine samples (5.09%) (X2=9.05 at P=0.05). Volunteers within the age group 26-30 years recorded the highest prevalence (4.46%), while those within the age group 36-40 years recorded the lowest at 1.27%(X2=4.34 at P=0.05). In pregnant female participants, the highest frequency was recorded with those in their 3rd trimester (4.14%), while lowest incidence was recorded for those in their first trimester (0.80%). Antibiogram results from this study showed that C. albicans isolates obtained from this study resisted Fluconazole (72%) more than Voriconazole (57%). Only one out of the six selected isolates yielded resistance in the MIC test. Results obtained from the RT-PCR showed that there was no expression of ERG11 gene among the fluconazole resistant isolates of C. albicans. Observed resistance may be due to other factors other than expression of ERG11 gene.

Keywords: candida, ERG11, triazole, nigeria

Procedia PDF Downloads 149
8975 Effect of Planting Techniques on Mangrove Seedling Establishment in Kuwait Bay

Authors: L. Al-Mulla, B. M. Thomas, N. R. Bhat, M. K. Suleiman, P. George

Abstract:

Mangroves are halophytic shrubs habituated in the intertidal zones in the tropics and subtropics, forming a complex and highly dynamic coastal ecosystem. Historical evidence indicating the existence followed by the extinction of mangrove in Kuwait; hence, continuous projects have been established to reintroduce this plant to the marine ecosystem. One of the major challenges in establishing large-scale mangrove plantations in Kuwait is the very high rate of seedling mortality, which should ideally be less than 20%. This study was conducted at three selected locations in the Kuwait bay during 2016-2017, to evaluate the effect of four planting techniques on mangrove seedling establishment. Coir-pillow planting technique, comp-mat planting technique, and anchored container planting technique were compared with the conventional planting method. The study revealed that the planting techniques significantly affected the establishment of mangrove seedlings in the initial stages of growth. Location-specific difference in seedling establishment was also observed during the course of the study. However, irrespective of the planting techniques employed, high seedling mortality was observed in all the planting locations towards the end of the study; which may be attributed to the physicochemical characteristics of the mudflats selected.

Keywords: Avicennia marina (Forsk.) Vierh, coastal pollution, heavy metal accumulation, marine ecosystem, sedimentation, tidal inundation

Procedia PDF Downloads 152
8974 Effect of Temperature and Feed Solution on Microencapsulation of Quercetin by Spray Drying Technique

Authors: S. Lekhavat, U. Srimongkoluk, P. Ratanachamnong, G. Laungsopapun

Abstract:

Quercetin was encapsulated with whey protein and high methoxyl pectin by spray drying technique. Feed solution, consisting of 0.1875 0.125 and 0.0625 % w/w quercetin, respectively, was prepared and then sprays at outlet temperature of 70, 80 and 90 °C. Quercetin contents either in feed solution or in spray dried powder were determined by HPLC technique. Physicochemical properties such as viscosity and total soluble solid of feed solution as well as moisture content and water activity of spray dried powder were examined. Particle morphology was imaged using scanning electron microscope. The results showed that feed solution has total soluble solid and viscosity in range of 1.73-5.60 ºBrix and 2.58-8.15 cP, in that order. After spray drying, the moisture content and water activity value of powder are in range of 0.58-2.72 % and 0.18-0.31, respectively. Quercetin content in dried sample increased along with outlet drying temperature but decreased when total soluble solid increased. It was shown that particles are likely to shrivel when spray drying at high temperature. The suggested conditions for encapsulation of quercetin are feed solution with 0.0625 % (w/w) quercetin and spray drying at drying outlet temperature of 90°C.

Keywords: drying temperature, particle morphology, spray drying, quercetin

Procedia PDF Downloads 260
8973 Analysis of Standard Tramway Surge Protection Methods Based on Real Cases

Authors: Alain Rousseau, Alfred Aragones, Gilles Rougier

Abstract:

The study is based on lightning and surge standards mainly the EN series 62305 for facility protection, EN series 61643 for Low Voltage Surge Protective Devices, High Voltage surge arrester standard en 60099-4 and the traction arrester standards namely EN 50526-1 and 50526-1 dealing respectively with railway applications fixed installations D.C. surge arresters and voltage limiting devices. The more severe stress for tramways installations is caused by direct lightning on the catenary line. In such case, the surge current propagates towards the various poles and sparkover the insulators leading to a lower stress. If the impact point is near enough, a significant surge current will flow towards the traction surge arrester that is installed on the catenary at the location the substation is connected. Another surge arrester can be installed at the entrance of the substation or even inside the rectifier to avoid insulation damages. In addition, surge arresters can be installed between + and – to avoid damaging sensitive circuits. Based on disturbances encountered in a substation following a lighting event, the engineering department of RATP has decided to investigate the cause of such damage and more generally to question the efficiency of the various possible protection means. Based on the example of a recent tramway line the paper present the result of a lightning study based on direct lightning strikes. As a matter of fact, the induced surges on the catenary are much more frequent but much less damaging. First, a lightning risk assessment is performed for the substations that takes into account direct lightning and induced lightning both on the substation and its connected lines such as the catenary. Then the paper deals with efficiency of the various surge arresters is discussed based on field experience and calculations. The efficiency of the earthing system used at the bottom of the pole is also addressed based on high frequency earthing measurement. As a conclusion, the paper is making recommendations for an enhanced efficiency of existing protection means.

Keywords: surge arrester, traction, lightning, risk, surge protective device

Procedia PDF Downloads 259
8972 Knowledge and Eating Behavior of Teenage Pregnancy

Authors: Udomporn Yingpaisuk, Premwadee Karuhadej

Abstract:

The purposed of this research was to study the eating habit of teenage pregnancy and its relationship to the knowledge of nutrition during pregnancy. The 100 samples were derived from simple random sampling technique of the teenage pregnancy in Bangkae District. The questionnaire was used to collect data with the reliability of 0.8. The data were analyzed by SPSS for Windows with multiple regression technique. Percentage, mean and the relationship of knowledge of eating and eating behavior were obtained. The research results revealed that their knowledge in nutrition was at the average of 4.07 and their eating habit that they mentioned most was to refrain from alcohol and caffeine at 82% and the knowledge in nutrition influenced their eating habits at 54% with the statistically significant level of 0.001.

Keywords: teenage pregnancy, knowledge of eating, eating behavior, alcohol, caffeine

Procedia PDF Downloads 358
8971 Cd1−xMnxSe Thin Films Preparation by Cbd: Aspect on Optical and Electrical Properties

Authors: Jaiprakash Dargad

Abstract:

CdMnSe dilute semiconductor or semimagnetic semiconductors have become the focus of intense research due to their interesting combination of magnetic and semiconducting properties, and are employed in a variety of devices including solar cells, gas sensors etc. A series of thin films of this material, Cd1−xMnxSe (0 ≤ x ≤ 0.5), were therefore synthesized onto precleaned amorphous glass substrates using a solution growth technique. The sources of cadmium (Cd2+) and manganese (Mn2+) were aqueous solutions of cadmium sulphate and manganese sulphate, and selenium (Se2−) was extracted from a reflux of sodium selenosulphite. The different deposition parameters such as temperature, time of deposition, speed of mechanical churning, pH of the reaction mixture etc were optimized to yield good quality deposits. The as-grown samples were thin, relatively uniform, smooth and tightly adherent to the substrate support. The colour of the deposits changed from deep red-orange to yellowish-orange as the composition parameter, x, was varied from 0 to 0.5. The terminal layer thickness decreased with increasing value of, x. The optical energy gap decreased from 1.84 eV to 1.34 eV for the change of x from 0 to 0.5. The coefficient of optical absorption is of the order of 10-4 - 10-5 cm−1 and the type of transition (m = 0.5) is of the band-to-band direct type. The dc electrical conductivities were measured at room temperature and in the temperature range 300 K - 500 K. It was observed that the room temperature electrical conductivity increased with the composition parameter x up to 0.1, gradually decreasing thereafter. The thermo power measurements showed n-type conduction in these films.

Keywords: dilute semiconductor, reflux, CBD, thin film

Procedia PDF Downloads 231
8970 Rainfall-Runoff Forecasting Utilizing Genetic Programming Technique

Authors: Ahmed Najah Ahmed Al-Mahfoodh, Ali Najah Ahmed Al-Mahfoodh, Ahmed Al-Shafie

Abstract:

In this study, genetic programming (GP) technique has been investigated in prediction of set of rainfall-runoff data. To assess the effect of input parameters on the model, the sensitivity analysis was adopted. To evaluate the performance of the proposed model, three statistical indexes were used, namely; Correlation Coefficient (CC), Mean Square Error (MSE) and Correlation of Efficiency (CE). The principle aim of this study is to develop a computationally efficient and robust approach for predict of rainfall-runoff which could reduce the cost and labour for measuring these parameters. This research concentrates on the Johor River in Johor State, Malaysia.

Keywords: genetic programming, prediction, rainfall-runoff, Malaysia

Procedia PDF Downloads 482
8969 Recovery of Draw Solution in Forward Osmosis by Direct Contact Membrane Distillation

Authors: Su-Thing Ho, Shiao-Shing Chen, Hung-Te Hsu, Saikat Sinha Ray

Abstract:

Forward osmosis (FO) is an emerging technology for direct and indirect potable water reuse application. However, successful implementation of FO is still hindered by the lack of draw solution recovery with high efficiency. Membrane distillation (MD) is a thermal separation process by using hydrophobic microporous membrane that is kept in sandwich mode between warm feed stream and cold permeate stream. Typically, temperature difference is the driving force of MD which attributed by the partial vapor pressure difference across the membrane. In this study, the direct contact membrane distillation (DCMD) system was used to recover diluted draw solution of FO. Na3PO4 at pH 9 and EDTA-2Na at pH 8 were used as the feed solution for MD since it produces high water flux and minimized salt leakage in FO process. At high pH, trivalent and tetravalent ions are much easier to remain at draw solution side in FO process. The result demonstrated that PTFE with pore size of 1 μm could achieve the highest water flux (12.02 L/m2h), followed by PTFE 0.45 μm (10.05 L/m2h), PTFE 0.1 μm (7.38 L/m2h) and then PP (7.17 L/m2h) while using 0.1 M Na3PO4 draw solute. The concentration of phosphate and conductivity in the PTFE (0.45 μm) permeate were low as 1.05 mg/L and 2.89 μm/cm respectively. Although PTFE with the pore size of 1 μm could obtain the highest water flux, but the concentration of phosphate in permeate was higher than other kinds of MD membranes. This study indicated that four kinds of MD membranes performed well and PTFE with the pore size of 0.45 μm was the best among tested membranes to achieve high water flux and high rejection of phosphate (99.99%) in recovery of diluted draw solution. Besides that, the results demonstrate that it can obtain high water flux and high rejection of phosphate when operated with cross flow velocity of 0.103 m/s with Tfeed of 60 ℃ and Tdistillate of 20 ℃. In addition to that, the result shows that Na3PO4 is more suitable for recovery than EDTA-2Na. Besides that, while recovering the diluted Na3PO4, it can obtain the high purity of permeate water. The overall performance indicates that, the utilization of DCMD is a promising technology to recover the diluted draw solution for FO process.

Keywords: membrane distillation, forward osmosis, draw solution, recovery

Procedia PDF Downloads 185
8968 A Comparison Study of Different Methods Used in the Detection of Giardia lamblia on Fecal Specimen of Children

Authors: Muhammad Farooq Baig

Abstract:

Objective: The purpose of this study was to compare results obtained using a single fecal specimen for O&P examination, direct immunofluorescence assay (DFA), and two conventional staining methods. Design: Hundred and fifty children fecal specimens were collected and examined by each method. The O&P and the DFA were used as the reference method. Setting: The study was performed at the laboratory in the Basic Medical Science Institute JPMC Karachi. Patients or Other Participants: The fecal specimens were collected from children with a suspected Giardia lamblia infection. Main Outcome Measures: The amount of agreement and disagreement between methods.1) Presence of giardiasis in our population. 2) The sensitivity and specificity of each method. Results: There was 45(30%) positive 105 (70%) negative on DFA, 41 (27.4%) positive 109 (72.6%) negative on iodine and 34 (22.6%) positive 116(77.4%) on saline method. The sensitivity and specificity of DFA in comparision to iodine were 92.2%, 92.7% respectively. The sensitivity and specificity of DFA in comparisoin to saline method were 91.2%, 87.9% respectively. The sensitivity of iodine method and saline method in compariosn to DFA were 82.2%, 68.8% respectively. There is mark diffrence in sensitivity of DFA to conventional method. Conclusion: The study supported findings of other investigators who concluded that DFA method have the greater sensitivity. The immunologic methods were more efficient and quicker than the conventional O&P method.

Keywords: direct immunofluorescence assay (DFA), ova and parasite (O&P), Giardia lamblia, children, medical science

Procedia PDF Downloads 423
8967 Influence of Thickness on Electrical and Structural Properties of Zinc Oxide (ZnO) Thin Films Prepared by RF Sputtering Technique

Authors: M. Momoh, S. Abdullahi, A. U. Moreh

Abstract:

Zinc oxide (ZnO) thin films were prepared on corning (7059) glass substrates at a thickness of 75.5 and 130.5 nm by RF sputtering technique. The deposition was carried out at room temperature after which the samples were annealed in open air at 150°C. The electrical and structural properties of these films were studied. The electrical properties of the films were monitored by four-point probe method while the structural properties were studied by X-ray diffraction (XRD). It was found that the electrical resistance of the films decreases with increase in the thickness of the films. The XRD analysis of the films showed that the films have a peak located at 34.31°-34.35° with hkl (002). Other parameters calculated include the stress (σ) and the grain size (D).

Keywords: electrical properties, film thickness, structural properties, zinc oxide

Procedia PDF Downloads 379
8966 Characterization of the Microbial Induced Carbonate Precipitation Technique as a Biological Cementing Agent for Sand Deposits

Authors: Sameh Abu El-Soud, Zahra Zayed, Safwan Khedr, Adel M. Belal

Abstract:

The population increase in Egypt is urging for horizontal land development which became a demand to allow the benefit of different natural resources and expand from the narrow Nile valley. However, this development is facing challenges preventing land development and agriculture development. Desertification and moving sand dunes in the west sector of Egypt are considered the major obstacle that is blocking the ideal land use and development. In the proposed research, the sandy soil is treated biologically using Bacillus pasteurii bacteria as these bacteria have the ability to bond the sand partials to change its state of loose sand to cemented sand, which reduces the moving ability of the sand dunes. The procedure of implementing the Microbial Induced Carbonate Precipitation Technique (MICP) technique is examined, and the different factors affecting on this process such as the medium of bacteria sample preparation, the optical density (OD600), the reactant concentration, injection rates and intervals are highlighted. Based on the findings of the MICP treatment for sandy soil, conclusions and future recommendations are reached.

Keywords: soil stabilization, biological treatment, microbial induced carbonate precipitation (MICP), sand cementation

Procedia PDF Downloads 243