Search results for: present morphologies
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 13316

Search results for: present morphologies

12596 Comparative Ante-Mortem Studies through Electrochemical Impedance Spectroscopy, Differential Voltage Analysis and Incremental Capacity Analysis on Lithium Ion Batteries

Authors: Ana Maria Igual-Munoz, Juan Gilabert, Marta Garcia, Alfredo Quijano-Lopez

Abstract:

Nowadays, several lithium-ion battery technologies are being commercialized. These chemistries present different properties that make them more suitable for different purposes. However, comparative studies showing the advantages and disadvantages of different chemistries are incomplete or scarce. Different non-destructive techniques are currently being employed to detect how ageing affects the active materials of lithium-ion batteries (LIBs). For instance, electrochemical impedance spectroscopy (EIS) is one of the most employed ones. This technique allows the user to identify the variations on the different resistances present in LIBs. On the other hand, differential voltage analysis (DVA) has shown to be a powerful technique to detect the processes affecting the different capacities present in LIBs. This technique shows variations in the state of health (SOH) and the capacities for one or both electrodes depending on their chemistry. Finally, incremental capacity analysis (ICA) is a widely known technique for being capable of detecting phase equilibria. It reminds of the commonly used cyclic voltamperometry, as it allows detecting some reactions taking place in the electrodes. In these studies, a set of ageing procedures have been applied to commercial batteries of different chemistries (NCA, NMC, and LFP). Afterwards, results of EIS, DVA, and ICA have been used to correlate them with the processes affecting each cell. Ciclability, overpotential, and temperature cycling studies envisage how the charge-discharge rates, cut-off voltage, and operation temperatures affect each chemistry. These studies will serve battery pack manufacturers, as for common battery users, as they will determine the different conditions affecting cells for each of the chemistry. Taking this into account, each cell could be adjusted to the final purpose of the battery application. Last but not least, all the degradation parameters observed are focused to be integrated into degradation models in the future. This fact will allow the implementation of the widely known digital twins to the degradation in LIBs.

Keywords: lithium ion batteries, non-destructive analysis, different chemistries, ante-mortem studies, ICA, DVA, EIS

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12595 Fractal: Formative Reflective Assessment and Critical Thinking in Learning

Authors: Yannis Stavrakakis, Damian Gordon

Abstract:

Critical Thinking and Reflective Practice are two vital skills that students undertaking postgraduate studies should ideally possess. To help students develop and enhance these skills, this research developed several authentic activities to be undertaken as part of a module that is delivered early in a taught MSc to enhance these skills. One of the challenges of these topics is that they are somewhat ill-defined in terms of precisely what they mean, and also, there is no clear route to operationalizing the teaching of these skills. This research focuses on identifying suitable models of these skills and delivering them in a manner that is both clear and highly motivating. To achieve this, a class of 22 Master's students was divided into two groups, one was provided with a presentation and checklist about critical thinking skills, and the other group was given the same materials on the reflective practice process. The groups were given two scenarios each to analyze using their respective checklists and were asked to present their outcomes to each other and give peer review. The results were coded and compared, and key differences were noted, including the fact that the Critical Thinking outcomes were more future-focused, and the Reflective Practice outcomes were more past-focused and present-focused, as well as the fact that the Reflective Practice process generated a significantly wider range of perspectives on the scenarios.

Keywords: critical thinking, ethical scenarios, formative assessment, reflective practice

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12594 Effect of Naphtha on the Composition of a Heavy Crude, in Addition to a Cycle Steam Stimulation Process

Authors: A. Guerrero, A. Leon, S. Munoz, M. Sandoval

Abstract:

The addition of solvent to cyclic steam stimulation is done in order to reduce the solvent-vapor ratio at late stages of the process, the moment in which this relationship increases significantly. The study of the use of naphtha in addition to the cyclic steam stimulation has been mainly oriented to the effect it achieves on the incremental recovery compared to the application of steam only. However, the effect of naphtha on the reactivity of crude oil components under conditions of cyclic steam stimulation or if its effect is the only dilution has not yet been considered, to author’s best knowledge. The present study aims to evaluate and understand the effect of naphtha and the conditions of cyclic steam stimulation, on the remaining composition of the improved oil, as well as the main mechanisms present in the heavy crude - naphtha interaction. Tests were carried out with the system solvent (naphtha)-oil (12.5° API, 4216 cP @ 40° C)- steam, in a batch micro-reactor, under conditions of cyclic steam stimulation (250-300 °C, 400 psi). The characterization of the samples obtained was carried out by MALDI-TOF MS (matrix-assisted laser desorption/ionization time-of-flight mass spectrometry) and NMR (Nuclear Magnetic Resonance) techniques. The results indicate that there is a rearrangement of the microstructure of asphaltenes, resulting in a decrease in these and an increase in lighter components such as resins.

Keywords: composition change, cyclic steam stimulation, interaction mechanism, naphtha

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12593 Comparative Acaricidal Efficacy of Fluralaner vs Oral Ivermectin Against Tick Infestation in Dogs

Authors: Tayyaba Zahra, Shehla Gul Bokhari, Asim Khalid Mahmood, Raheela Akhtar, Khizar Matloob

Abstract:

In Pakistan, dogs are commonly infested with ticks, especially in summers, causing not only dermatological issues but also systemic problems. Persistence of tick infestation often leads to heavy losses. Different acaricides are locally available with variable efficacy; however, recurrence of infestation is commonly reported. The present study was thus designed to compare the efficacy of a novel drug Fluralaner and conventionally used Ivermectin against tick infestation. Dogs positive for tick infestation were randomly divided into 2 groups viz, Groups A and B having 8 dogs each. Ticks were enumerated manually from the whole body of dogs at day 0 before the administration of drugs Dogs in Group A were treated with Fluralaner at day 0, and dogs in Group B were treated with Ivermectin. Post-treatment, ticks were counted again at days 7, 14, 21, 28, and 35. At day 07 of the study, no tick was found on the dogs treated with Fluralaner, while many ticks were present on the dogs treated with Ivermectin showing an efficacy up to 50%. On the consecutive follow-up evaluations, similar results were found for Fluralaner while the efficacy of Ivermectin was further reduced to less than 50%. Furthermore, Fluralaner treated dogs had better RBC counts, PCV, Hgb concentration, LFTs, RFTs post-treatment than the dogs treated with Ivermectin. Statistically, oral Fluralaner proved a more effective drug (P≤0.05)than oral Ivermectin against tick infestation in dogs.

Keywords: fluralaner, ivermectin, dogs, tick infestations

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12592 Levels of Heavy Metals in Different Tissues of Lethrinus Miniatus Fish from Arabian Gulf

Authors: Muhammad Waqar Ashraf

Abstract:

In the present study, accumulation of eight heavy metals, lead (Pb), cadmium (Cd), manganese (Mn), copper (Cu), zinc (Zn), iron (Fe), nickel (Ni) and chromium (Cr)was determined in kidney, heart, liver and muscle tissues of Lethrinus Miniatus fish caught from Arabian Gulf. Metal concentrations in all the samples were measured using Graphite Furnace Atomic Absorption Spectroscopy (GF-AAS). Analytical validation of data was carried out by applying the same digestion procedure to standard reference material (NIST-SRM 1577b bovine liver). Levels of lead (Pb) in the liver tissue (0.60µg/g) exceeded the limit set by European Commission (2005) at 0.30 µg/g. Zinc concentration in all tissue samples were below the maximum permissible limit (50 µg/g) as set by FAO. Maximum mean cadmium concentration was found to be 0.15 µg/g in the kidney tissues. Highest content of Mn in the studied tissues was seen in the kidney tissue (2.13 µg/g), whereas minimum was found in muscle tissue (0.87 µg/g). The present study led to the conclusion that muscle tissue is the least contaminated tissue in Lethrinus Miniatus and consumption of organs should be avoided as much as possible.

Keywords: Arabian gulf, Lethrinus miniatus, heavy metals, atomic absorption spectroscopy

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12591 Plant Cell Culture to Produce Valuable Natural Products

Authors: Jehad Dumireih, Malak Dmirieh, Michael Wink

Abstract:

The present work is aimed to use plant cell suspension cultures of Crataegus monogyna for biosynthesis of valuable natural products by using quercetin as an inexpensive precursor. Suspension cell cultures of C. monogyna were established by using Murashige and Skoog medium (MS) supplemented with 1 mg/L 2,4-dichlorophenoxyacetic acid and 1 mg/L kinetin. Cells were harvested from the cultures and extracted by using methanol and ethyl acetate; then the extracts were used for the identification of isoquercetin by HPLC and by mass spectrometry. The incubation of the cells with 0.24 mM quercetin for one week resulted in an 16 fold increase of isoquercetin biosynthesis; the growth rate of the cells increased by 20%. Moreover, the biosynthesis of isoquercetin was enhanced by 40% when we divided the added quercetin into three portions each one with concentration 0.12 mM supplied at 3 days intervals. In addition, we didn’t find any positive effects of adding different concentrations the precursors phenylalanine (0.2 mM) and galactose to the cell cultures. In conclusion, the efficiency of the biotransformation of quercetin into isoquercetin depended on the concentration quercetin, its incubation time and the way of its administration. The results of the present work suggest that the biotechnological methods such as cell suspension cultures could be successfully used to obtain highly valuable natural product starting from inexpensive compound.

Keywords: biosynthesis, biotransformation, Crataegus, isoquercetin

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12590 Fe-BTC Based Electrochemical Sensor for Anti-Psychotic and Anti-Migraine Drugs: Aripiprazole and Rizatriptan

Authors: Sachin Saxena, Manju Srivastava

Abstract:

The present study describes a stable, highly sensitive and selective analytical sensor. Fe-BTC was synthesized at room temperature using the noble Iron-trimesate system. The high surface area of as synthesized Fe-BTC proved MOFs as ideal modifiers for glassy carbon electrode. The characterization techniques such as TGA, XRD, FT-IR, BET (BET surface area= 1125 m2/gm) analysis explained the electrocatalytic behaviour of Fe-BTC towards these two drugs. The material formed is cost effective and exhibit higher catalytic behaviour towards analyte systems. The synergism between synthesized Fe-BTC and electroanalytical techniques helped in developing a highly sensitive analytical method for studying the redox fate of ARP and RZ, respectively. Cyclic voltammetry of ferricyanide system proved Fe-BTC/GCE with an increase in 132% enhancement in peak current value as compared to that of GCE. The response characteristics of cyclic voltammetry (CV) and square wave voltammetry (SWV) revealed that the ARP and RZ could be effectively accumulated at Fe-BTC/GCE. On the basis of the electrochemical measurements, electrode dynamics parameters have been evaluated. Present study opens up new field of applications of MOFs modified GCE for drug sensing.

Keywords: MOFs, anti-psychotic, electrochemical sensor, anti-migraine drugs

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12589 Vibration control of Bridge Super structure using Tuned Mass Damper (TMD)

Authors: Tauhidur Rahman, Dhrubajyoti Thakuria

Abstract:

In this article, vibration caused by earthquake excitation, wind load and the high-speed vehicle in the superstructure has been studied. An attempt has been made to control these vibrations using passive Tuned Mass Dampers (TMD). Tuned mass damper consists of a mass, spring, and viscous damper which dissipates the vibration energy of the primary structure at the damper of the TMD. In the present paper, the concrete box girder bridge superstructure is considered and is modeled using MIDAS software. The bridge is modeled as Euler-Bernoulli beam to study the responses imposed by high-speed vehicle, earthquake excitation and wind load. In the present study, comparative study for the responses has been done considering different velocities of the train. The results obtained in this study are based on Indian standard loadings specified in Indian Railways Board (Bridge Rules). A comparative study has been done for the responses of the high-speed vehicle with and without Tuned Mass Dampers. The results indicate that there is a significant reduction in displacement and acceleration in the bridge superstructure when Tuned Mass Damper is used.

Keywords: bridge superstructure, high speed vehicle, tuned mass damper, TMD, vibration control

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12588 Investigating University Language Teacher’s Perception of Their Identities in the Algerian Multilingual Context

Authors: Yousra Drissi

Abstract:

This research explores language teacher identity in a multilingual context where both teachers and students come from different linguistic backgrounds. It seeks to understand how teachers perceive themselves as language teachers in this context in relation to different influencing factors, both internal and external. This study is being conducted due to the importance of language teacher identity (LTI) in the university context, which is being neglected in the present literature (in an attempt to address the gap in the present literature). The broader aim of this study is to bring attention to language teacher identity along with the different influencing elements which can either promote or hinder its development. In this research, we are using the sociocultural theory and post-structural theory. This research uses the mixed methods approach to collect and analyse relevant data. A structured survey was distributed to language teachers from different universities around Algeria, followed by in-depth interviews. Results are supposed to show the different points in self-perception that these teachers share or differ in. they will also help us identify the different internal and external factors that can be of influence. However, the results of this research can be used by institutions as well as decision-makers to better understand university teachers and help them improve their teaching practices by empowering their language teacher identity, starting from teacher education programs to continuous teacher development programs.

Keywords: identity, language teacher identity, multilingualism, university teacher

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12587 Academic Literacy: Semantic-Discursive Resource and the Relationship with the Constitution of Genre for the Development of Writing

Authors: Lucia Rottava

Abstract:

The present study focuses on academic literacy and addresses the impact of semantic-discursive resources on the constitution of genres that are produced in such context. The research considers the development of writing in the academic context in Portuguese. Researches that address academic literacy and the characteristics of the texts produced in this context are rare, mainly with focus on the development of writing, considering three variables: the constitution of the writer, the perception of the reader/interlocutor and the organization of the informational text flow. The research aims to map the semantic-discursive resources of the written register in texts of several genres and produced by students in the first semester of the undergraduate course in letters. The hypothesis raised is that writing in the academic environment is not a recurrent literacy practice for these learners and can be explained by the ontogenetic and phylogenetic nature of language development. Qualitative in nature, the present research has as empirical data texts produced in a half-yearly course of Reading and Textual Production; these data result from the proposition of four different writing proposals, in a total of 600 texts. The corpus is analyzed based on semantic-discursive resources, seeking to contemplate relevant aspects of language (grammar, discourse and social context) that reveal the choices made in the reader/writer interrelationship and the organizational flow of the text. Among the semantic-discursive resources, the analysis includes three resources, including (a) appraisal and negotiation to understand the attitudes negotiated (roles of the participants of the discourse and their relationship with the other); (b) ideation to explain the construction of the experience (activities performed and participants); and (c) periodicity to outline the flow of information in the organization of the text according to the genre it instantiates. The results indicate the organizational difficulties of the flow of the text information. Cartography contributes to the understanding of the way writers use language in an effort to present themselves, evaluate someone else’s work, and communicate with readers.

Keywords: academic writing, portuguese mother tongue, semantic-discursive resources, sistemic funcional linguistic

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12586 Economic Evaluation of Bowland Shale Gas Wells Development in the UK

Authors: Elijah Acquah-Andoh

Abstract:

The UK has had its fair share of the shale gas revolutionary waves blowing across the global oil and gas industry at present. Although, its exploitation is widely agreed to have been delayed, shale gas was looked upon favorably by the UK Parliament when they recognized it as genuine energy source and granted licenses to industry to search and extract the resource. This, although a significant progress by industry, there yet remains another test the UK fracking resource must pass in order to render shale gas extraction feasible – it must be economically extractible and sustainably so. Developing unconventional resources is much more expensive and risky, and for shale gas wells, producing in commercial volumes is conditional upon drilling horizontal wells and hydraulic fracturing, techniques which increase CAPEX. Meanwhile, investment in shale gas development projects is sensitive to gas price and technical and geological risks. Using a Two-Factor Model, the economics of the Bowland shale wells were analyzed and the operational conditions under which fracking is profitable in the UK was characterized. We find that there is a great degree of flexibility about Opex spending; hence Opex does not pose much threat to the fracking industry in the UK. However, we discover Bowland shale gas wells fail to add value at gas price of $8/ Mmbtu. A minimum gas price of $12/Mmbtu at Opex of no more than $2/ Mcf and no more than $14.95M Capex are required to create value within the present petroleum tax regime, in the UK fracking industry.

Keywords: capex, economical, investment, profitability, shale gas development, sustainable

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12585 English Theticity and Focus Expression in Spanish Heritage Speakers

Authors: Sebastian Leal-Arenas

Abstract:

English uses in-situ Nuclear Stress (NS) to express the meanings of theticity and focus. The NS is phonetically represented by an increase in duration, intensity, and pitch range. On the other hand, Spanish conveys the same meanings by aligning the constituent that carries the NS to the end of the sentence via word-order movement. However, little is known about heritage speakers’ production of theticity and focus in English or Spanish. The present study investigates heritage speakers’ production of thetic and subject focus statements. Participants (n = 11) were heritage speakers of Spanish with varying proficiency enrolled in a writing course at a university in the United States. In the production task, participants observed contextualized images and uttered a sentence to answer a provided question. Duration, intensity, and F0 peak were the correlates to stress considered in this investigation. Results indicated that participants tended to present an intonation closer to what is expected in English monolinguals in subject-focus statements than in thetic sentences. However, participants with lower Spanish proficiency used in-situ NS placement in thetic statements more often than those with higher proficiency. Results are discussed in terms of the production patterns observed in heritage speakers with emphasis on the role of language dominance.

Keywords: focus, heritage speakers, prosody, theticity

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12584 Use of Chemical Extractions to Estimate the Metals Availability in Bricks Made of Dredged Sediments

Authors: Fabienne Baraud, Lydia Leleyter, Sandra Poree, Melanie Lemoine

Abstract:

SEDIBRIC (valorization de SEDIments en BRIQues et tuiles) is a French project that aims to replace a part of natural clays with dredged sediments in the preparation of fired bricks in order to propose an alternative solution for the management of harbor dredged sediments. The feasibility of such re-use is explored from a technical, economic, and environmental point of view. The present study focuses on the potential environmental impact of various chemical elements (Al, Ca, Cd, Co, Cr, Cu, Fe, Ni, Mg, Mn, Pb, Ti, and Zn) that are initially present in the dredged sediments. The total content (after acid digestion) and the environmental availability (estimated by single extractions with various extractants) of these elements are determined in the raw sediments and in the obtained fired bricks. The possible influence of some steps of the manufacturing process (sediment pre-treatment, firing) is also explored. The first results show that the pre-treatment step, which uses tap water to desalinate the raw sediment, does not influence the environmental availability of the studied elements. However, the firing process, performed at 900°C, can affect the amount of some elements detected in the bricks, as well as their environmental availability. We note that for Cr, or Ni, the HCl or EDTA availability was increased in the brick (compared to the availability in the raw sediment). For Cd, Cu, Pb, and Zn, the HCl and EDTA availability was reduced in the bricks, meaning that these elements were stabilized within the bricks.

Keywords: bricks, chemical extraction, metals, sediment

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12583 An Analysis of the Regression Hypothesis from a Shona Broca’s Aphasci Perspective

Authors: Esther Mafunda, Simbarashe Muparangi

Abstract:

The present paper tests the applicability of the Regression Hypothesis on the pathological language dissolution of a Shona male adult with Broca’s aphasia. It particularly assesses the prediction of the Regression Hypothesis, which states that the process according to which language is forgotten will be the reversal of the process according to which it will be acquired. The main aim of the paper is to find out whether mirror symmetries between L1 acquisition and L1 dissolution of tense in Shona and, if so, what might cause these regression patterns. The paper also sought to highlight the practical contributions that Linguistic theory can make to solving language-related problems. Data was collected from a 46-year-old male adult with Broca’s aphasia who was receiving speech therapy at St Giles Rehabilitation Centre in Harare, Zimbabwe. The primary data elicitation method was experimental, using the probe technique. The TART (Test for Assessing Reference Time) Shona version in the form of sequencing pictures was used to access tense by Broca’s aphasic and 3.5-year-old child. Using the SPSS (Statistical Package for Social Studies) and Excel analysis, it was established that the use of the future tense was impaired in Shona Broca’s aphasic whilst the present and past tense was intact. However, though the past tense was intact in the male adult with Broca’s aphasic, a reference to the remote past was made. The use of the future tense was also found to be difficult for the 3,5-year-old speaking child. No difficulties were encountered in using the present and past tenses. This means that mirror symmetries were found between L1 acquisition and L1 dissolution of tense in Shona. On the basis of the results of this research, it can be concluded that the use of tense in a Shona adult with Broca’s aphasia supports the Regression Hypothesis. The findings of this study are important in terms of speech therapy in the context of Zimbabwe. The study also contributes to Bantu linguistics in general and to Shona linguistics in particular. Further studies could also be done focusing on the rest of the Bantu language varieties in terms of aphasia.

Keywords: Broca’s Aphasia, regression hypothesis, Shona, language dissolution

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12582 Cameroon’s State Bilingualism: Mending Fences between Linguistic Communities

Authors: Charles Esambe Alobwede

Abstract:

From the time of the biblical story of the Tower of Babel, languages as well as people have learnt to co-exist. It is obvious that when languages co-exist, there is the inevitable tendency of linguistic influence. This is because a language can either be a unifying factor or a factor of division within a given community, especially in a multicultural and multi-linguistic community where such a situation has led to socio-political and economic tension. Thus, leaders of such communities have a duty to plan and implement a language policy that will meet the needs of all members of the community in order to enhance its corporateness. The present article will focus on some of the major reasons that prompted the government of Cameroon to embark on an official bilingual policy after independence in 1961 and then evaluate the evolution of the linguistic situation. The article will equally look at the consequences, especially on a socio-political platform and what today has been termed 'the Anglophone problem' in Cameroon which has caused a fuse between the country’s minority Anglophone population and the majority Francophone administration. Data for the present article is collected from literature on the state of official bilingualism in Cameroon, newspapers articles on the prevailing situation in the country and interviews with actors on the field.

Keywords: language policy, linguistic influence, multicultural, official bilingualism, socio-political tension

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12581 Iranian Students’ and Teachers’ Perceptions of Effective Foreign Language Teaching

Authors: Mehrnoush Tajnia, Simin Sadeghi-Saeb

Abstract:

Students and teachers have different perceptions of effectiveness of instruction. Comparing students’ and teachers’ beliefs and finding the mismatches between them can increase L2 students’ satisfaction. Few studies have taken into account the beliefs of both students and teachers on different aspects of pedagogy and the effect of learners’ level of education and contexts on effective foreign language teacher practices. Therefore, the present study was conducted to compare students’ and teachers’ perceptions on effective foreign language teaching. A sample of 303 learners and 54 instructors from different private language institutes and universities participated in the study. A questionnaire was developed to elicit participants’ beliefs on effective foreign language teaching and learning. The analysis of the results revealed that: a) there is significant difference between the students’ beliefs about effective teacher practices and teachers’ belief, b) Class level influences students’ perception of effective foreign language teacher, d) There is a significant difference of opinion between those learners who study foreign languages at university and those who study foreign language in private institutes with respect to effective teacher practices. The present paper concludes that finding the gap between students’ and teachers’ beliefs would help both of the groups to enhance their learning and teaching.

Keywords: effective teacher, effective teaching, students’ beliefs, teachers’ beliefs

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12580 Utilising Sociodrama as Classroom Intervention to Develop Sensory Integration in Adolescents who Present with Mild Impaired Learning

Authors: Talita Veldsman, Elzette Fritz

Abstract:

Many children attending special education present with sensory integration difficulties that hamper their learning and behaviour. These learners can benefit from therapeutic interventions as part of their classroom curriculum that can address sensory development and allow for holistic development to take place. A research study was conducted by utilizing socio-drama as a therapeutic intervention in the classroom in order to develop sensory integration skills. The use of socio-drama as therapeutic intervention proved to be a successful multi-disciplinary approach where education and psychology could build a bridge of growth and integration. The paper describes how socio-drama was used in the classroom and how these sessions were designed. The research followed a qualitative approach and involved six Afrikaans-speaking children attending special secondary school in the age group 12-14 years. Data collection included observations during the session, reflective art journals, semi-structured interviews with the teacher and informal interviews with the adolescents. The analysis found improved self-confidence, better social relationships, sensory awareness and self-regulation in the participants after a period of a year.

Keywords: education, sensory integration, sociodrama, classroom intervention, psychology

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12579 Effect of Piston and its Weight on the Performance of a Gun Tunnel via Computational Fluid Dynamics

Authors: A. A. Ahmadi, A. R. Pishevar, M. Nili

Abstract:

As the test gas in a gun tunnel is non-isentropically compressed and heated by a light weight piston. Here, first consideration is the optimum piston weight. Although various aspects of the influence of piston weight on gun tunnel performance have been studied, it is not possible to decide from the existing literature what piston weight is required for optimum performance in various conditions. The technique whereby the piston is rapidly brought to rest at the end of the gun tunnel barrel, and the resulted peak pressure is equal in magnitude to the final equilibrium pressure, is called the equilibrium piston technique. The equilibrium piston technique was developed to estimate the equilibrium piston mass; but this technique cannot give an appropriate estimate for the optimum piston weight. In the present work, a gun tunnel with diameter of 3 in. is described and its performance is investigated numerically to obtain the effect of piston and its weight. Numerical results in the present work are in very good agreement with experimental results. Significant influence of the existence of a piston is shown by comparing the gun tunnel results with results of a conventional shock tunnel in the same dimension and same initial condition. In gun tunnel, an increase of around 250% in running time is gained relative to shock tunnel. Also, Numerical results show that equilibrium piston technique is not a good way to estimate suitable piston weight and there will be a lighter piston which can increase running time of the gun tunnel around 60%.

Keywords: gun tunnel, hypersonic flow, piston, shock tunnel

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12578 Kinetics and Specificity of Drosophila melanogaster Molybdo-Flavoenzymes towards Their Substrates

Authors: Khaled S. Al Salhen

Abstract:

Aldehyde oxidase (AO) and xanthine oxidoreductase (XOR) catalyze the oxidation of many different N-heterocyclic compounds as well as aliphatic and aromatic aldehydes to their corresponding lactam and carboxylic acids respectively. The present study examines the oxidation of dimethylamino-cinnamaldehyde (DMAC), vanillin and phenanthridine by AO and xanthine by XOR from Drosophila cytosol. Therefore, the results obtained in the present study showed the DMAC, vanillin and phenanthridine substrates used were found to be good substrates of Drosophila AO and xanthine is the preferred substrate for Drosophila XOR. Km values of AO substrates were observed with DMAC (50±5.4 µM), phenanthridine (80±9.1 µM) and vanillin (303±11.7 µM) respectively for Drosophila cytosol. The Km values for DMAC and phenanthridine were ~6 and ~4 fold lower than that for vanillin as a substrate. The Km for XOR with xanthine using NAD+ as an electron acceptor was 27±4.1 µM. Relatively low Vmax values were obtained with phenanthridine (1.78±0.38 nmol/min/mg protein) and DMAC (1.80±0.35 nmol/min/mg protein). The highest Vmax was obtained from Drosophila cytosol with vanillin (7.58±2.11 nmol/min/mg protein). It is concluded these results that AO and XOR in Drosophila were able to catalyse the biotransformation of numerous substrates of the well-characterised mammalian AO and XOR. The kinetic parameters have indicated that the activity of AO of Drosophila may be a significant factor the oxidation of aromatic aldehyde compounds.

Keywords: aldehyde oxidase, xanthine oxidoreductase, dimethylamino-cinnamaldehyde, vanillin, phenanthridine, Drosophila melanogaster

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12577 Role of Matric Suction in Mechanics behind Swelling Characteristics of Expansive Soils

Authors: Saloni Pandya, Nikhil Sharma, Ajanta Sachan

Abstract:

Expansive soils in the unsaturated state are part of vadose zone and encountered in several arid and semi-arid parts of the world. Influence of high temperature, low precipitation and alternate cycles of wetting and drying are responsible for the chemical weathering of rocks, which results in the formation of expansive soils. Shrinkage-swelling (expansive) soils cover a substantial portion of area in India. Damages caused by expansive soils to various geotechnical structures are alarming. Matric suction develops in unsaturated soil due to capillarity and surface tension phenomena. Matric suction influences the geometric arrangement of soil skeleton, which induces the volume change behaviour of expansive soil. In the present study, an attempt has been made to evaluate the role of matric suction in the mechanism behind swelling characteristics of expansive soil. Four different soils have been collected from different parts of India for the current research. Soil sample S1, S2, S3 and S4 were collected from Nagpur, Bharuch, Bharuch-Dahej highway and Ahmedabad respectively. DFSI (Differential Free Swell Index) of these soils samples; S1, S2, S3, and S4; were determined to be 134%, 104%, 70% and 30% respectively. X-ray diffraction analysis of samples exhibited that percentage of Montmorillonite mineral present in the soils reduced with the decrease in DFSI. A series of constant volume swell pressure tests and in-contact filter paper tests were performed to evaluate swelling pressure and matric suction of all four soils at 30% saturation and 1.46 g/cc dry density. Results indicated that soils possessing higher DFSI exhibited higher matric suction as compared to lower DFSI expansive soils. Significant influence of matric suction on swelling pressure of expansive soils was observed with varying DFSI values. Higher matric suction of soil might govern the water uptake in the interlayer spaces of Montmorillonite mineral present in expansive soil leading to crystalline swelling.

Keywords: differential free swell index, expansive soils, matric suction, swelling pressure

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12576 Incorporating Spatial Selection Criteria with Decision-Maker Preferences of A Precast Manufacturing Plant

Authors: M. N. A. Azman, M. S. S. Ahamad

Abstract:

The Construction Industry Development Board of Malaysia has been actively promoting the use of precast manufacturing in the local construction industry over the last decade. In an era of rapid technological changes, precast manufacturing significantly contributes to improving construction activities and ensuring sustainable economic growth. Current studies on the location decision of precast manufacturing plants aimed to enhanced local economic development are scarce. To address this gap, the present research establishes a new set of spatial criteria, such as attribute maps and preference weights, derived from a survey of local industry decision makers. These data represent the input parameters for the MCE-GIS site selection model, for which the weighted linear combination method is used. Verification tests on the model were conducted to determine the potential precast manufacturing sites in the state of Penang, Malaysia. The tests yield a predicted area of 12.87 acres located within a designated industrial zone. Although, the model is developed specifically for precast manufacturing plant but nevertheless it can be employed to other types of industries by following the methodology and guidelines proposed in the present research.

Keywords: geographical information system, multi criteria evaluation, industrialised building system, civil engineering

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12575 Using Scrum in an Online Smart Classroom Environment: A Case Study

Authors: Ye Wei, Sitalakshmi Venkatraman, Fahri Benli, Fiona Wahr

Abstract:

The present digital world poses many challenges to various stakeholders in the education sector. In particular, lecturers of higher education (HE) are faced with the problem of ensuring that students are able to achieve the required learning outcomes despite rapid changes taking place worldwide. Different strategies are adopted to retain student engagement and commitment in classrooms to address the differences in learning habits, preferences, and styles of the digital generation of students recently. Further, the onset of the coronavirus disease (COVID-19) pandemic has resulted in online teaching being mandatory. These changes have compounded the problems in the learning engagement and short attention span of HE students. New agile methodologies that have been successfully employed to manage projects in different fields are gaining prominence in the education domain. In this paper, we present the application of Scrum as an agile methodology to enhance student learning and engagement in an online smart classroom environment. We demonstrate the use of our proposed approach using a case study to teach key topics in information technology that require students to gain technical and business-related data analytics skills.

Keywords: agile methodology, Scrum, online learning, smart classroom environment, student engagement, active learning

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12574 The Imperative of Adult Education in the Knowledge Society

Authors: Najim Akorede Babalola

Abstract:

Adult Education is a multi and interdisciplinary in nature that cut across different fields of study which includes education, social sciences, engineering even information technologies that dominate the contemporary world among others. In the past, Adult Education has been used as an instrument of civilization by teaching people how to read and write as well as earning a better living. The present world has witnessed a transition from industrial age to information age which is also known as knowledge society needs Adult Education for knowledge acquisition and update of existing knowledge. An individual needs Adult Education in either of its various forms (on-the-job-training, in-service training, extramural classes, vocational education, continuing education among others) in order to develop towards the information society trends; this is because Adult Education is a process of transforming an individual through acquisition of relevant skills and knowledge for personal as well as societal development. Evidence abounds in the literature that Adult Education has not only assisted people in the medieval period but still assisting people in this modern society in changing and transforming their lives for a better living. This study, therefore, raised a salient question that with different ideas and innovations brought by the contemporary world, is Adult Education relevant? It is on this basis that this study intends to examine the relevance of Adult Education in the past and present in order to determine its future relevance.

Keywords: adult education, multi and inter-disciplinary, knowledge society, skill acquisition

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12573 The Effect of Protexin and Curcuma Longa on Growth Performance, Serum Lipid and Immune Organ Weight of Broilers at Starter Period

Authors: Farhad Ahmadi, Mehran Mohammadi Khah, Fariba Rahimi, N. Vejdani Far

Abstract:

The aim of present research was to investigate the effect of different levels of protexin (PRT) and Curcuma longa (CUR) on performance, serum lipid and indices of immune system in broiler chickens at the starter stage. A total of 300, one-day-old male broiler (Ross-308) were allotted, in a 2×2+1 factorial design contain 2 levels of protexin (10 and 40 mg/kg diet) and 2 levels of Curcuma longa (200 and 400 mg/kg diet) with four replicate and 15 birds per pens. Experimental diets were: T1 control (basal diet); T2 (2g/kg CUR+0.1g PRT/kg diet), T3 (2g CUR/kg+0.2g PRT/kg diet), T4 (4g CUR/kg+0.1g PRT/kg) and T5 (4g CUR/kg+0.2g PRT/kg). Results indicated that body weight gain and feed conversion ratio had significantly improved (P < 0.05) in birds that fed diet inclusion any levels of additive. The highest BWG and lowest FCR observed in T5 birds group as compared to control (P < 0.05). Relative bursa of Fabricius and spleen weight in T5 and T3 birds groups were higher than control (P > 0.05). The serum of cholesterol, TG, LDL had significantly decreased (P < 0.05). As well, HDL was higher (P < 0.05) in T5 birds group compared to control. In conclusion, results of present trial indicated that blend of mention additive was better than using individual of those and improved performance traits.

Keywords: broiler, Curcuma longa, performance, protexin, serum

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12572 An Approach to Consumption of Exhaustible Resources Based on Islamic Justice and Hartwick Criteria

Authors: Hamed Najafi, Ghasem Nikjou

Abstract:

Nowadays, there is an increasing attention to the resources scarcity issues. Because of failure in present patterns in the field of the allocation of exhaustible resources between generations and the challenges related to economic justice supply, it is supposed, to present a pattern from the Islamic perspective in this essay. By using content analysis of religious texts, we conclude that governments should remove the gap which is exists between the per capita income of the poor and their minimum consumption (necessary consumption). In order to preserve the exhaustible resources for poor people) not for all), between all generations, government should invest exhaustible resources on endless resources according to Hartwick’s criteria and should spend these benefits for poor people. But, if benefits did not cover the gap between minimum consumption and per capita income of poor levels in one generation, in this case, the government is responsible for covering this gap through the direct consumption of exhaustible resources. For an exact answer to this question, ‘how much of exhaustible resources should expense to maintain justice between generations?’ The theoretical and mathematical modeling has been used and proper function has been provided. The consumption pattern is presented for economic policy makers in Muslim countries, and non-Muslim even, it can be useful.

Keywords: exhaustible resources, Islamic justice, intergenerational justice, distribution of resources, Hartwick criteria

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12571 Application of the Piloting Law Based on Adaptive Differentiators via Second Order Sliding Mode for a Fixed Wing Aircraft

Authors: Zaouche Mohammed, Amini Mohammed, Foughali Khaled, Hamissi Aicha, Aktouf Mohand Arezki, Boureghda Ilyes

Abstract:

In this paper, we present a piloting law based on the adaptive differentiators via high order sliding mode controller, by using an aircraft in virtual simulated environment. To deal with the design of an autopilot controller, we propose a framework based on Software in the Loop (SIL) methodology and we use MicrosoftTM Flight Simulator (FS-2004) as the environment for plane simulation. The aircraft dynamic model is nonlinear, Multi-Input Multi-Output (MIMO) and tightly coupled. The nonlinearity resides in the dynamic equations and also in the aerodynamic coefficients' variability. In our case, two (02) aircrafts are used in the flight tests, the Zlin-142 and MQ-1 Predator. For both aircrafts and in a very low altitude flight, we send the piloting control inputs to the aircraft which has stalled due to a command disconnection. Then, we present the aircraft’s dynamic behavior analysis while reestablishing the command transmission. Finally, a comparative study between the two aircraft’s dynamic behaviors is presented.

Keywords: adaptive differentiators, second order sliding modes, dynamic adaptation of the gains, microsoft flight simulator, Zlin-142, MQ-1 predator

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12570 ISSR Based Molecular Phylogeny in Naturally Growing Suaeda Populations of Saudi Arabia

Authors: Mohammed Abdullah Basahi

Abstract:

The objective of the present study was to identify the phylogenetic relationships and determine genetic diversity among Suaeda genotypes growing in Saudi Arabia and to find out whether these could be a potential source for genetic diversity. A set of nineteen genotypes was analyzed using twenty-four ISSR primers. Clear amplified polymorphic DNA products were obtained from the screening of twenty-four ISSR primers on nineteen genotypes that allowed selection of ten primers and the results were reproducible. Nineteen genotypes were revealed a unique profile with ten ISSR primers and thus it can be used for the DNA fingerprinting. Different primers produced a different level of polymorphism among the nineteen genotypes. The number of polymorphic bands per primer varied from 5 to 14 with an average of 8 bands per primer. The results revealed that the genotypes differed for ISSR markers. The genetic similarity based on Nei and Li’s ranged from 0.450 to 0.930. Cluster analysis was conducted based on ISSR data to group the Suaeda genotypes and to construct a dendrogram. Four groups can be distinguished by truncating the dendrogram at GS value of 0.54. ISSR markers showed high level of polymorphism among the genotypes examined. The present study indicates that ISSR markers could be successfully used in genetic characterization and diversity in Suaeda.

Keywords: suaeda, DNA fingerprinting, ISSR, Saudi Arabia

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12569 Maturity Status of Male Boys in Punjab - India

Authors: Parminder K. Laroiya, Sukhdeep S. Kang

Abstract:

The Present cross-sectional study was conducted on 610 boys (ranging in age bracket of 11 to 17 years) to assess their developmental age to check percentage of early, normal and late maturity among them, and to check whether there is any significant difference in their calendar age and developmental age. Developmental age of these subjects has been accessed by TW2 method (using hand wrist X-rays) and their chronological age was checked from their date of birth certificate. Developmental status of subjects i.e. early, normal or late mature was considered with +2 years or -2 years from their calendar age. Results of this study shows that 50% boys were normal in their maturity status in all age brackets and rest of subjects were either early maturers 24.92% or late maturers 25.08%. When pattern of maturity was studied in each age group it has been found that till the age of 15 years, percentage of normal maturity was less than 50 % whereas in 16 and 17 years age groups, this percentage of normal maturity increased to 60% - 65 % ( this may be because at this age mostly boys attain adolescence) Further investigation of each age group showed that till the age of 14 years percentage of late maturity among these boys were approximately 35% to 40% whereas early maturity lies between 15% to 20%. It has been found from the present study that at the age of 15 years, there is a twist among percentage of late and early maturity among boys-early maturers are 38.61% and late maturers are 16.84%. At the age of 16 and 17 years percentage of late maturity has been decreased to 3% to 6%, whereas percentage of early maturity increased to 35.64 % and 30.69 % respectively.

Keywords: maturity status, developmental age, chronological age, X-rays

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12568 Mechanical and Tribological Properties of Al7075 Reinforced with Graphene-Beryl Hybrid Metal Matrix Composites

Authors: Mohamed Haneef, Shanawaz Patil, Syed Zameer, Mohammed Mohsin Ali

Abstract:

The emerging technologies and trends of present generation requires downsizing the unwieldy structures to light weight structures on one hand and integration of varied properties on other hand to meet the application demands. In the present investigation an attempt is made to familiarize and best possibilities of reinforcing agent in aluminum 7075 matrix with naturally occurring beryl (Be) and graphene (Gr) to develop a new hybrid composite material. A stir casting process was used to fabricate with fixed volume fraction of 6wt% weight beryl and various volume fractions of 0.5wt%, 1wt%, 1.5wt% and 2wt% of graphene. The properties such as tensile strength, hardness and dry sliding wear behavior of hybrid composites were examined. The crystallite size and morphology of the graphene and beryl particles were analyzed with X-ray diffraction (XRD) and scanning electron microscopy (SEM) respectively. It was observed that ultimate tensile strength and hardness of the hybrid composite increased with increasing reinforcement volume fraction as compared to specimen without reinforcement additions. The dry sliding wear behavior of the hybrid composites decreases as compared to Al7075 alloy without reinforcement.

Keywords: Al7075, beryl, graphene, TEM, wear

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12567 Torsional Rigidities of Reinforced Concrete Beams Subjected to Elastic Lateral Torsional Buckling

Authors: Ilker Kalkan, Saruhan Kartal

Abstract:

Reinforced concrete (RC) beams rarely undergo lateral-torsional buckling (LTB), since these beams possess large lateral bending and torsional rigidities owing to their stocky cross-sections, unlike steel beams. However, the problem of LTB is becoming more and more pronounced in the last decades as the span lengths of concrete beams increase and the cross-sections become more slender with the use of pre-stressed concrete. The buckling moment of a beam mainly depends on its lateral bending rigidity and torsional rigidity. The nonhomogeneous and elastic-inelastic nature of RC complicates estimation of the buckling moments of concrete beams. Furthermore, the lateral bending and torsional rigidities of RC beams and the buckling moments are affected from different forms of concrete cracking, including flexural, torsional and restrained shrinkage cracking. The present study pertains to the effects of concrete cracking on the torsional rigidities of RC beams prone to elastic LTB. A series of tests on rather slender RC beams indicated that torsional cracking does not initiate until buckling in elastic LTB, while flexural cracking associated with lateral bending takes place even at the initial stages of loading. Hence, the present study clearly indicated that the un-cracked torsional rigidity needs to be used for estimating the buckling moments of RC beams liable to elastic LTB.

Keywords: lateral stability, post-cracking torsional rigidity, uncracked torsional rigidity, critical moment

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