Search results for: mass communication
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 7568

Search results for: mass communication

1778 Learning Outcomes Alignment across Engineering Core Courses

Authors: A. Bouabid, B. Bielenberg, S. Ainane, N. Pasha

Abstract:

In this paper, a team of faculty members of the Petroleum Institute in Abu Dhabi, UAE representing six different courses across General Engineering (ENGR), Communication (COMM), and Design (STPS) worked together to establish a clear developmental progression of learning outcomes and performance indicators for targeted knowledge, areas of competency, and skills for the first three semesters of the Bachelor of Sciences in Engineering curriculum. The sequences of courses studied in this project were ENGR/COMM, COMM/STPS, and ENGR/STPS. For each course’s nine areas of knowledge, competency, and skills, the research team reviewed the existing learning outcomes and related performance indicators with a focus on identifying linkages across disciplines as well as within the courses of a discipline. The team reviewed existing performance indicators for developmental progression from semester to semester for same discipline related courses (vertical alignment) and for different discipline courses within the same semester (horizontal alignment). The results of this work have led to recommendations for modifications of the initial indicators when incoherence was identified, and/or for new indicators based on best practices (identified through literature searches) when gaps were identified. It also led to recommendations for modifications of the level of emphasis within each course to ensure developmental progression. The exercise has led to a revised Sequence Performance Indicator Mapping for the knowledge, skills, and competencies across the six core courses.

Keywords: curriculum alignment, horizontal and vertical progression, performance indicators, skill level

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1777 Patient Service Improvement in Public Emergency Department Using Discrete Event Simulation

Authors: Dana Mohammed, Fatemah Abdullah, Hawraa Ali, Najat Al-Shaer, Rawan Al-Awadhi, , Magdy Helal

Abstract:

We study the patient service performance at the emergency department of a major Kuwaiti public hospital, using discrete simulation and lean concepts. In addition to the common problems in such health care systems (over crowdedness, facilities planning and usage, scheduling and staffing, capacity planning) the emergency department suffered from several cultural and patient behavioural issues. Those contributed significantly to the system problems and constituted major obstacles in maintaining the performance in control. This led to overly long waiting times and the potential of delaying providing help to critical cases. We utilized the visual management tools to mitigate the impact of the patients’ behaviours and attitudes and improve the logistics inside the system. In addition a proposal is made to automate the date collection and communication within the department using RFID-based barcoding system. Discrete event simulation models were developed as decision support systems; to study the operational problems and assess achieved improvements. The simulation analysis resulted in cutting the patient delays to about 35% of their current values by reallocating and rescheduling the medical staff. Combined with the application of the visual management concepts, this provided the basis to improving patient service without any major investments.

Keywords: simulation, visual management, health care system, patient

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1776 Polyphenol-Rich Aronia Melanocarpa Juice Consumption and Line-1 Dna Methylation in a Cohort at Cardiovascular Risk

Authors: Ljiljana Stojković, Manja Zec, Maja Zivkovic, Maja Bundalo, Marija Glibetić, Dragan Alavantić, Aleksandra Stankovic

Abstract:

Cardiovascular disease (CVD) is associated with alterations in DNA methylation, the latter modulated by dietary polyphenols. The present pilot study (part of the original clinical study registered as NCT02800967 at www.clinicaltrials.gov) aimed to investigate the impact of 4-week daily consumption of polyphenol-rich Aronia melanocarpa juice on Long Interspersed Nucleotide Element-1 (LINE-1) methylation in peripheral blood leukocytes, in subjects (n=34, age of 41.1±6.6 years) at moderate CVD risk, including an increased body mass index, central obesity, high normal blood pressure and/or dyslipidemia. The goal was also to examine whether factors known to affect DNA methylation, such as folate intake levels, MTHFR C677T gene variant, as well as the anthropometric and metabolic parameters, modulated the LINE-1 methylation levels upon consumption of polyphenol-rich Aronia juice. The experimental analysis of LINE-1 methylation was done by the MethyLight method. MTHFR C677T genotypes were determined by the polymerase chain reaction-restriction fragment length polymorphism method. Folate intake was assessed by processing the data from the food frequency questionnaire and repeated 24-hour dietary recalls. Serum lipid profile was determined by using Roche Diagnostics kits. The statistical analyses were performed using the Statistica software package. In women, after vs. before the treatment period, a significant decrease in LINE-1 methylation levels was observed (97.54±1.50% vs. 98.39±0.86%, respectively; P=0.01). The change (after vs. before treatment) in LINE-1 methylation correlated directly with MTHFR 677T allele presence, average daily folate intake and the change in serum low-density lipoprotein cholesterol, while inversely with the change in serum triacylglycerols (R=0.72, R2=0.52, adjusted R2=0.36, P=0.03). The current results imply potential cardioprotective effects of habitual polyphenol-rich Aronia juice consumption achieved through the modifications of DNA methylation pattern in subjects at CVD risk, which should be further confirmed. Hence, the precision nutrition-driven modulations of DNA methylation may become targets for new approaches in the prevention and treatment of CVD.

Keywords: Aronia melanocarpa, cardiovascular risk, LINE-1, methylation, peripheral blood leukocytes, polyphenol

Procedia PDF Downloads 200
1775 Experimental Design in Extraction of Pseudomonas sp. Protease from Fermented Broth by Polyethylene Glycol/Citrate Aqueous Two-Phase System

Authors: Omar Pillaca-Pullo, Arturo Alejandro-Paredes, Carol Flores-Fernandez, Marijuly Sayuri Kina, Amparo Iris Zavaleta

Abstract:

Aqueous two-phase system (ATPS) is an interesting alternative for separating industrial enzymes due to it is easy to scale-up and low cost. Polyethylene glycol (PEG) mixed with potassium phosphate or magnesium sulfate is one of the most frequently polymer/salt ATPS used, but the consequences of its use is a high concentration of phosphates and sulfates in wastewater causing environmental issues. Citrate could replace these inorganic salts due to it is biodegradable and does not produce toxic compounds. On the other hand, statistical design of experiments is widely used for ATPS optimization and it allows to study the effects of the involved variables in the purification, and to estimate their significant effects on selected responses and interactions. The 24 factorial design with four central points (20 experiments) was employed to study the partition and purification of proteases produced by Pseudomonas sp. in PEG/citrate ATPS system. ATPS was prepared with different sodium citrate concentrations [14, 16 and 18% (w/w)], pH values (7, 8 and 9), PEG molecular weight (2,000; 4,000 and 6,000 g/mol) and PEG concentrations [18, 20 and 22 % (w/w)]. All system components were mixed with 15% (w/w) of the fermented broth and deionized water was added to a final weight of 12.5 g. Then, the systems were mixed and kept at room temperature until to reach two-phases separation. Volumes of the top and bottom phases were measured, and aliquots from both phases were collected for subsequent proteolytic activity and total protein determination. Influence of variables such as PEG molar mass (MPEG), PEG concentration (CPEG), citrate concentration (CSal) and pH were evaluated on the following responses: purification factor (PF), activity yield (Y), partition coefficient (K) and selectivity (S). STATISTICA program version 10 was used for the analysis. According to the obtained results, higher levels of CPEG and MPEG had a positive effect on extraction, while pH did not influence on the process. On the other hand, the CSal could be related with low values of Y because of the citrate ions have a negative effect on solubility and enzymatic structure. The optimum values of Y (66.4 %), PF (1.8), K (5.5) and S (4.3) were obtained at CSal (18%), MPEG (6,000 g/mol), CPEG (22%) and pH 9. These results indicated that the PEG/citrate system is accurate to purify these Pseudomonas sp. proteases from fermented broth as a first purification step.

Keywords: citrate, polyethylene glycol, protease, Pseudomonas sp

Procedia PDF Downloads 200
1774 Traditional Women's Clothes at Tekirdağ Region

Authors: E. Elhan Özus, Melek Tufan, Filiz Erden

Abstract:

Cloth is a special wearing style of a society for a period or of a profession. Clothes reflect the social status difference than the fashion. Within this context, society forms a wearing style in the direction of its customs, usage, traditions and social structure. One of the properties of a society indicating the social levels and cultural differences differing the societies from each other is clothing style. Clothing is one of the most important needs in life depending on the individual and social attributes. The clothing which first emerged as protection means is a social fact complementing the physical and psychological existence of human being, changing forms depending on technological developments and phases, and continuously changing under the affect of fashion today. Clothing is an aesthetic value fed by the feelings of individuals. So, clothing has an indispensable place in the structure and communication of cultural and social identity within this direction. The traditional Turkish clothing has a rich ethnography. It is also possible to see the winds coming from our predecessors in these cultural assets reflecting the feelings and thoughts of Anatolian women. When the long history of our nation and the cultures interacted by our nation are taken into account, it is seen that the magnificence of our nation has also reflected into the clothing culture.For this reason, we tried to keep the traditional women’s clothing of Tekirdağ region alive by investigating and documenting them. In this study, it is purposed to contribute a little bit to protect our culture and form a source for the future generations, to carry our national cultural values from the past up to now and to the future and deliver to the young people.

Keywords: Turkish, traditional, culture, clothing

Procedia PDF Downloads 345
1773 3D Multiuser Virtual Environments in Language Teaching

Authors: Hana Maresova, Daniel Ecler

Abstract:

The paper focuses on the use of 3D multi-user virtual environments (MUVE) in language teaching and presents the results of four years of research at the Faculty of Education, Palacký University in Olomouc (Czech Republic). In the form of an experiment, mother tongue language teaching in the 3D virtual worlds Second Life and Kitely (experimental group) and parallel traditional teaching on identical topics representing teacher's interpretation using a textbook (control group) were implemented. The didactic test, which was presented to the experimental and control groups in an identical form before and after the instruction, verified the effect of the instruction in the experimental group by comparing the results obtained by both groups. Within the three components of mother-tongue teaching (vocabulary, literature, style and communication education), the students in the literature group achieved partially better results (statistically significant in the case of items devoted to the area of visualization of the learning topic), while in the case of grammar and style education the respondents of the control group achieved better results. On the basis of the results obtained, we can conclude that the most appropriate use of MUVE can be seen in the teaching of those topics that provide the possibility of dramatization, experiential learning and group involvement and cooperation, on the contrary, with regard to the need to divide students attention between the topic taught and the control of avatar and movement in virtual reality as less suitable for teaching in the area of memorization of the topic or concepts.

Keywords: distance learning, 3D virtual environments, online teaching, language teaching

Procedia PDF Downloads 165
1772 Feasibility Study and Experiment of On-Site Nuclear Material Identification in Fukushima Daiichi Fuel Debris by Compact Neutron Source

Authors: Yudhitya Kusumawati, Yuki Mitsuya, Tomooki Shiba, Mitsuru Uesaka

Abstract:

After the Fukushima Daiichi nuclear power reactor incident, there are a lot of unaccountable nuclear fuel debris in the reactor core area, which is subject to safeguard and criticality safety. Before the actual precise analysis is performed, preliminary on-site screening and mapping of nuclear debris activity need to be performed to provide a reliable data on the nuclear debris mass-extraction planning. Through a collaboration project with Japan Atomic Energy Agency, an on-site nuclear debris screening system by using dual energy X-Ray inspection and neutron energy resonance analysis has been established. By using the compact and mobile pulsed neutron source constructed from 3.95 MeV X-Band electron linac, coupled with Tungsten as electron-to-photon converter and Beryllium as a photon-to-neutron converter, short-distance neutron Time of Flight measurement can be performed. Experiment result shows this system can measure neutron energy spectrum up to 100 eV range with only 2.5 meters Time of Flightpath in regards to the X-Band accelerator’s short pulse. With this, on-site neutron Time of Flight measurement can be used to identify the nuclear debris isotope contents through Neutron Resonance Transmission Analysis (NRTA). Some preliminary NRTA experiments have been done with Tungsten sample as dummy nuclear debris material, which isotopes Tungsten-186 has close energy absorption value with Uranium-238 (15 eV). The results obtained shows that this system can detect energy absorption in the resonance neutron area within 1-100 eV. It can also detect multiple elements in a material at once with the experiment using a combined sample of Indium, Tantalum, and silver makes it feasible to identify debris containing mixed material. This compact neutron Time of Flight measurement system is a great complementary for dual energy X-Ray Computed Tomography (CT) method that can identify atomic number quantitatively but with 1-mm spatial resolution and high error bar. The combination of these two measurement methods will able to perform on-site nuclear debris screening at Fukushima Daiichi reactor core area, providing the data for nuclear debris activity mapping.

Keywords: neutron source, neutron resonance, nuclear debris, time of flight

Procedia PDF Downloads 241
1771 Ab Initio Calculations of Structure and Elastic Properties of BexZn1−xO Alloys

Authors: S. Lakel, F. Elhamra, M. Ibrir, K. Almi

Abstract:

There is a growing interest in Zn1-xBexO (ZBO)/ZnO hetero structures and quantum wells since the band gap energy of Zn1-xBexO solid solutions can be turned over a very large range (3.37–10.6 eV) as a function of the Be composition. ZBO/ZnO has been utilized in ultraviolet light emission diodes and lasers, and may find applications as active elements of various other electronic and optoelectronic devices. Band gap engineering by Be substitution enables the facile preparation of barrier layers and quantum wells in device structures. In addition, ZnO and its ternary alloys, as piezoelectric semiconductors, have been used for high-frequency surface acoustic wave devices in wireless communication systems due to their high acoustic velocities and large electromechanical coupling. However, many important parameters such as elastic constants, bulk modulus, Young’s modulus and band-gap bowing. First-principles calculations of the structural, electrical and elastic properties of Zn1-xBexO as a function of the Be concentration x have been performed within density functional theory using norm-conserving pseudopotentials and local density approximation (LDA) for the exchange and correlation energy. The alloys’ lattice constants may deviate from the Vegard law. As Be concentration increases, the elastic constants, the bulk modulus and Young’s modulus of the alloys increase, the band gap increases with increasing Be concentration and Zn1-xBexO alloys have direct band. Our calculated results are in good agreement with experimental data and other theoretical calculations.

Keywords: DFT calculation, norm-conserving pseudopotentials, ZnBeO alloys, ZnO

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1770 The Analysis of Internet and Social Media Behaviors of the Students in Vocational High School

Authors: Mehmet Balci, Sakir Tasdemir, Mustafa Altin, Ozlem Bozok

Abstract:

Our globalizing world has become almost a small village and everyone can access any information at any time. Everyone lets each other know who does whatever in which place. We can learn which social events occur in which place in the world. From the perspective of education, the course notes that a lecturer use in lessons in a university in any state of America can be examined by a student studying in a city of Africa or the Far East. This dizzying communication we have mentioned happened thanks to fast developments in computer technologies and in parallel with this, internet technology. While these developments in the world, has a very large young population and a rapidly evolving electronic communications infrastructure Turkey has been affected by this situation. Researches has shown that almost all young people in Turkey has an account in a social network. Especially becoming common of mobile devices causes data traffic in social networks to increase. In this study, has been surveyed on students in the different age groups and at the Selcuk University Vocational School of Technical Sciences Department of Computer Technology. Student’s opinions about the use of internet and social media has been gotten. Using the Internet and social media skills, purposes, operating frequency, access facilities and tools, social life and effects on vocational education etc. have been explored. Both internet and use of social media positive and negative effects on this department students results have been obtained by the obtained findings evaluating from various aspects. Relations and differences have been found out with statistic.

Keywords: computer technologies, internet use, social network, higher vocational school

Procedia PDF Downloads 546
1769 Visual Design of Walkable City as Sidewalk Integration with Dukuh Atas MRT Station in Jakarta

Authors: Nadia E. Christiana, Azzahra A. N. Ginting, Ardhito Nurcahya, Havisa P. Novira

Abstract:

One of the quickest ways to do a short trip in urban areas is by walking, either individually, in couple or groups. Walkability nowadays becomes one of the parameters to measure the quality of an urban neighborhood. As a Central Business District and public transport transit hub, Dukuh Atas area becomes one of the highest numbers of commuters that pass by the area and interchange between transportation modes daily. Thus, as a public transport hub, a lot of investment should be focused to speed up the development of the area that would support urban transit activity between transportation modes, one of them is revitalizing pedestrian walkways. The purpose of this research is to formulate the visual design concept of 'Walkable City' based on the results of the observation and a series of rankings. To achieve this objective, it is necessary to accomplish several stages of the research that consists of (1) Identifying the system of pedestrian paths in Dukuh Atas area using descriptive qualitative method (2) Analyzing the sidewalk walkability rate according to the perception and the walkability satisfaction rate using the characteristics of pedestrians and non-pedestrians in Dukuh Atas area by using Global Walkability Index analysis and Multicriteria Satisfaction Analysis (3) Analyzing the factors that determine the integration of pedestrian walkways in Dukuh Atas area using descriptive qualitative method. The results achieved in this study is that the walkability level of Dukuh Atas corridor area is 44.45 where the value is included in the classification of 25-49, which is a bit of facility that can be reached by foot. Furthermore, based on the questionnaire, satisfaction rate of pedestrian walkway in Dukuh Atas area reached a number of 64%. It is concluded that commuters have not been fully satisfied with the condition of the sidewalk. Besides, the factors that influence the integration in Dukuh Atas area have been reasonable as it is supported by the utilization of land and modes such as KRL, Busway, and MRT. From the results of all analyzes conducted, the visual design and the application of the concept of walkable city along the pathway pedestrian corridor of Dukuh Atas area are formulated. Achievement of the results of this study amounted to 80% which needs to be done further review of the results of the analysis. The work of this research is expected to be a recommendation or input for the government in the development of pedestrian paths in maximizing the use of public transportation modes.

Keywords: design, global walkability index, mass rapid transit, walkable city

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1768 Optimizing Cell Culture Performance in an Ambr15 Microbioreactor Using Dynamic Flux Balance and Computational Fluid Dynamic Modelling

Authors: William Kelly, Sorelle Veigne, Xianhua Li, Zuyi Huang, Shyamsundar Subramanian, Eugene Schaefer

Abstract:

The ambr15™ bioreactor is a single-use microbioreactor for cell line development and process optimization. The ambr system offers fully automatic liquid handling with the possibility of fed-batch operation and automatic control of pH and oxygen delivery. With operating conditions for large scale biopharmaceutical production properly scaled down, micro bioreactors such as the ambr15™ can potentially be used to predict the effect of process changes such as modified media or different cell lines. In this study, gassing rates and dilution rates were varied for a semi-continuous cell culture system in the ambr15™ bioreactor. The corresponding changes to metabolite production and consumption, as well as cell growth rate and therapeutic protein production were measured. Conditions were identified in the ambr15™ bioreactor that produced metabolic shifts and specific metabolic and protein production rates also seen in the corresponding larger (5 liter) scale perfusion process. A Dynamic Flux Balance model was employed to understand and predict the metabolic changes observed. The DFB model-predicted trends observed experimentally, including lower specific glucose consumption when CO₂ was maintained at higher levels (i.e. 100 mm Hg) in the broth. A Computational Fluid Dynamic (CFD) model of the ambr15™ was also developed, to understand transfer of O₂ and CO₂ to the liquid. This CFD model predicted gas-liquid flow in the bioreactor using the ANSYS software. The two-phase flow equations were solved via an Eulerian method, with population balance equations tracking the size of the gas bubbles resulting from breakage and coalescence. Reasonable results were obtained in that the Carbon Dioxide mass transfer coefficient (kLa) and the air hold up increased with higher gas flow rate. Volume-averaged kLa values at 500 RPM increased as the gas flow rate was doubled and matched experimentally determined values. These results form a solid basis for optimizing the ambr15™, using both CFD and FBA modelling approaches together, for use in microscale simulations of larger scale cell culture processes.

Keywords: cell culture, computational fluid dynamics, dynamic flux balance analysis, microbioreactor

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1767 An Assessment of Factors Affecting the Cost and Time Performance of Subcontractors

Authors: Adedayo Jeremiah Adeyekun, Samuel Oluwagbemiga Ishola,

Abstract:

This paper is an assessment of factors influencing the cost and time performance of subcontractors and the need for effective performance of subcontractors at the project sites. The factors influencing the performance of subcontractors are grouped, similar to those identified with the project or an organization and on another hand, there are significant factors influencing the performance of the subcontractors. These factors incorporate management level leadership, time required to complete the project, profit, staff capability/expertise, reputation, installment method, organization history, and project procurement method strategy, security, bidding technique, insurance, bond and relationship with the major contractors. The factors influencing the management of subcontractors in building development projects includes performance of significant past projects, standard of workmanship, consistence with guidelines, regular payment to labourers, adherence to program, regularity and viability of communication with main contractor, adherence to subcontract necessities. Other factors comprise adherence to statutory environmental regulations, number of experienced sites administrative staff, inspection and maintenance of good workplace, number of artisans and workers, quality of as-built and shop drawings and ability to carry out the quantity of work and so on. This study also aimed to suggest a way forward to improve the performance of subcontractors which is the reason for exceeding budget at the project sites. To carry out this study, a questionnaire was drafted to derive information on the causes of low performance of subcontractors and the implication to cost.

Keywords: performance, contractor, subcontractors, construction

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1766 Modeling the Effects of Leachate-Impacted Groundwater on the Water Quality of a Large Tidal River

Authors: Emery Coppola Jr., Marwan Sadat, Il Kim, Diane Trube, Richard Kurisko

Abstract:

Contamination sites like landfills often pose significant risks to receptors like surface water bodies. Surface water bodies are often a source of recreation, including fishing and swimming, which not only enhances their value but also serves as a direct exposure pathway to humans, increasing their need for protection from water quality degradation. In this paper, a case study presents the potential effects of leachate-impacted groundwater from a large closed sanitary landfill on the surface water quality of the nearby Raritan River, situated in New Jersey. The study, performed over a two year period, included in-depth field evaluation of both the groundwater and surface water systems, and was supplemented by computer modeling. The analysis required delineation of a representative average daily groundwater discharge from the Landfill shoreline into the large, highly tidal Raritan River, with a corresponding estimate of daily mass loading of potential contaminants of concern. The average daily groundwater discharge into the river was estimated from a high-resolution water level study and a 24-hour constant-rate aquifer pumping test. The significant tidal effects induced on groundwater levels during the aquifer pumping test were filtered out using an advanced algorithm, from which aquifer parameter values were estimated using conventional curve match techniques. The estimated hydraulic conductivity values obtained from individual observation wells closely agree with tidally-derived values for the same wells. Numerous models were developed and used to simulate groundwater contaminant transport and surface water quality impacts. MODFLOW with MT3DMS was used to simulate the transport of potential contaminants of concern from the down-gradient edge of the Landfill to the Raritan River shoreline. A surface water dispersion model based upon a bathymetric and flow study of the river was used to simulate the contaminant concentrations over space within the river. The modeling results helped demonstrate that because of natural attenuation, the Landfill does not have a measurable impact on the river, which was confirmed by an extensive surface water quality study.

Keywords: groundwater flow and contaminant transport modeling, groundwater/surface water interaction, landfill leachate, surface water quality modeling

Procedia PDF Downloads 265
1765 Effects of Work Load and Surface Acting on Emotional Exhaustion and Work Satisfaction of Social Worker Students: Chinese Indigenous Ren-Qing Shi-Ku Trait as Moderator

Authors: Chung-Kwei Wang, Kuo-Ying Lo

Abstract:

The study is aimed to examine main and moderation effect of Chinese traditional social wisdom ‘Ren-qing Shi-kuon' the adjustment of social worker students during their practicum. Ren-qing Shi-ku as a social wisdom has been emphasized by collective-oriented Chinese society for thousand years. Based on interview and literature review, we operationalized the concept as four factors, including ‘harmonious interaction’, ‘understanding and tolerance’, ‘empathetic communication’ and ‘rule abiding’. We administer the scale to 96 social worker senior students before their summer practicums begins and collect their response on emotion labor, emotional exhaustion, work load, work satisfaction. We also ask their supervisors rated their performance on empathy, interpersonal relationships, performance on practicum and their Ren-qing Shi-ku performance. Results indicated that self-ratings of students on Ren-qing Shi-ku scale are correlated with rating from their supervisors. Students who have higher Ren-qing Shi-ku have better adjustment and higher ratings from their supervisor. Ren-qing Shi-ku also moderate effects of surface acting labor and work load on emotional exhaustion and work satisfaction. However, Ren-qing Shi-ku seems more beneficial under low work load situations. The finding of this study suggested traditional social skill training might be very effective for social service providers in a collective-oriented culture.

Keywords: emotion labor, ren-qing shi-ku, emotional exhaustion, work satisfaction and performance

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1764 Microwave Dielectric Properties and Microstructures of Nd(Ti₀.₅W₀.₅)O₄ Ceramics for Application in Wireless Gas Sensors

Authors: Yih-Chien Chen, Yue-Xuan Du, Min-Zhe Weng

Abstract:

Carbon monoxide is a substance produced by the incomplete combustion. It is toxic even at concentrations of less than 100ppm. Since it is colorless and odorless, it is difficult to detect. CO sensors have been developed using a variety of physical mechanisms, including semiconductor oxides, solid electrolytes, and organic semiconductors. Many works have focused on using semiconducting sensors composed of sensitive layers such as ZnO, TiO₂, and NiO with high sensitivity for gases. However, these sensors working at high temperatures increased their power consumption. On the other hand, the dielectric resonator (DR) is attractive for gas detection due to its large surface area and sensitivity for external environments. Materials that are to be employed in sensing devices must have a high-quality factor. Numerous researches into the fergusonite-type structure and related ceramic systems have explored. Extensive research into RENbO₄ ceramics has explored their potential application in resonators, filters, and antennas in modern communication systems, which are operated at microwave frequencies. Nd(Ti₀.₅W₀.₅)O₄ ceramics were synthesized herein using the conventional mixed-oxide method. The Nd(Ti₀.₅W₀.₅)O₄ ceramics were prepared using the conventional solid-state method. Dielectric constants (εᵣ) of 15.4-19.4 and quality factor (Q×f) of 3,600-11,100 GHz were obtained at sintering temperatures in the range 1425-1525°C for 4 h. The dielectric properties of the Nd(Ti₀.₅W₀.₅)O₄ ceramics at microwave frequencies were found to vary with the sintering temperature. For a further understanding of these microwave dielectric properties, they were analyzed by densification, X-ray diffraction (XRD), and by making microstructural observations.

Keywords: dielectric constant, dielectric resonators, sensors, quality factor

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1763 Employee Job Performance and Supervisor Workplace Gossip Employee Job Engagement's Mediation Effect

Authors: Pphakamani Irvine Dlamini

Abstract:

The impact of supervisory gossip on subordinate work performance was investigated in this paper. The paper postulated that supervisory gossip, both bad and positive, has an impact on employee job engagement, which in turn has an impact on employee job performance. Data was collected from 238 employees and supervisors from the Mpumalanga Government Municipality in South Africa using a dyadic study approach. Employees responded to questions on supervisor gossip and job engagement, while supervisors responded to questions about employee work performance. Three waves of data gathering were carried out. Favourable superior gossip had a positive and substantial effect on employee job engagement, which increased employee job performance, according to the study, but negative superior gossip had a positive but insignificant effect on employee job engagement. The multicultural aspect of the municipality, as well as causation concerns and frequent method biases connected with research design, hampered the study. After successfully disentangling the supervisor-subordinate reciprocal communication web using Social Exchange Theory (SET), the study suggests that managers should instil effective ways for using both positive and negative gossip in the workplace to achieve favourable employee outcomes. Positive gossip creates workplace rivalry and competition, but negative gossip creates tension, stress, and mistrust among employees. This study attempted to assess the implication of supervisor gossip on employee job engagement and performance in the public service sector, whose employees are characterised by high job security as compared to their peers in the private sector.

Keywords: worlplace gossip, supervisor, employee engagement, LMX

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1762 Effect of Women`s Autonomy on Unmet Need for Contraception and Family Size in India

Authors: Anshita Sharma

Abstract:

India is one of the countries to initiate family planning with intention to control the growing population by reducing fertility. In effort to this, India had introduced the National family planning programme in 1952. The level of unmet need in India shows a reducing trend with increasing effectiveness of family planning services as in NFHS-1 the unmet need for limiting, spacing and total was 46 percent, 14 percent & 9 percent, respectively. The demand for spacing has reduced to at 8 percent, 8 percent for limiting and total unmet need was 16 percent in NFHS-2. The total unmet need has reduced to 13 percent in NFHS-3 for all currently married women and the demand for limiting and spacing is 7 percent and 6 percent respectively. The level of unmet need in India shows a reducing trend with increasing effectiveness of family planning services. Despite the progress, there is chunk of women who are deprived of controlling unintended and unwanted pregnancies. The present paper examines the socio-cultural and economic and demographic correlates of unmet need for contraception in India. It also examines the effect of women’s autonomy and unmet need for contraception on family size among different socio-economic groups of population. It uses data from national family health survey-3 carried out in 2005-06 and employs bi-variate techniques and multivariate techniques for analysis. The multiple regression analysis has done to seek the level and direction of relationship among various socio-economic and demographic factors. The result reveals that women with higher level of education and economic status have low level of unmet need for family planning. Women living in non-nuclear family have high unmet need for spacing and women living in nuclear family have high unmet need for limiting and family size is slightly higher of women of nuclear family. In India, the level of autonomy varies at different life point; usually women with higher age enjoy higher autonomy than their junior female member in the family. The finding shows that women with higher autonomy have large family size counter to women with low autonomy have low family size. Unmet need for family planning decrease with women’s increasing exposure to mass- media. The demographic factors like experience of child loss are directly related to family size. Women who experience higher child loss have low unmet need for spacing and limiting. Thus, It is established with the help that women’s autonomy status play substantial role in fulfilling demand of contraception for limiting and spacing which affect the family size.

Keywords: family size, socio-economic correlates, unmet need for limiting, unmet need for spacing, women`s autonomy

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1761 Current Concepts of Male Aesthetics: Facial Areas to Be Focused and Prioritized with Botulinum Toxin and Hyaluronic Acid Dermal Fillers Combination Therapies, Recommendations on Asian Patients

Authors: Sadhana Deshmukh

Abstract:

Objective: Men represent only a fraction of the medical aesthetic practice. They are increasingly becoming more cosmetically-inclined. The primary objective is to harmonize facial proportion by prioritizing and focusing on forehead nose, cheek and chin complex. Introduction: Despite tremendous variability, diverse population of the Indian subcontinent, the male skull is unique in its overall larger size, and shape. Men tend to have a large forehead with prominent supraorbital ridges, wide glabella, square orbit, and a prominent protruding mandible. Men have increased skeletal muscle mass, with less facial subcutaneous fat. Facial aesthetics is evolving rapidly. Commonly published canons of facial proportions usually represent feminine standards and are not applicable to males. Strict adherence to these norms is therefore not necessary to obtain satisfying results in male patients. Materials and Methods: Male patients age group 30-60 years have been enrolled. Botulinum toxin and hyaluronic acid fillers were used to update consensus recommendations for facial rejuvenation using these two types of products alone and in combination. Results: There are specific recommendations by facial area, focusing on relaxing musculature, restoring volume, recontouring using toxin and dermal fillers alone and in combination. For upper face, though botulinum toxin remains the cornerstone of treatment, temples and forehead fillers are recommended for optimal results. In Mid face, these fillers are placed more laterally to maintain the masculine look. Botulinum toxin and fillers in combination can improve outcomes in the lower face. Chin augmentation remains the center point for lower face. Conclusions: Males are more likely to have shorter doctor visits, less likely to ask questions, have a lower attention to bodily changes. The physician must patiently gauge male patients’ aging and cosmetic goals. Clinicians can also benefit from ongoing guidance on products, tailoring treatments, treating multiple facial areas, and using combinations of products. An appreciation that rejuvenation is 3-dimensional process involving muscle control, volume restoration and recontouring helps.

Keywords: male aesthetics, botulinum toxin, hyaluronic acid dermal fillers, Asian patients

Procedia PDF Downloads 161
1760 Utilizing the RhlR/RhlI Quorum Sensing System to Express the ß-Galactosidase Reporter Gene by Using the N-Butanoyl Homoserine Lactone and N-Hexanoyl Homoserine Lactone

Authors: Ngoc Tu Truong, Nuong T. Bui, Ben Rao, Ya L. Shen

Abstract:

Quorum sensing is a phenomenon present in many gram-negative bacteria that allows bacterial communication and controlled expression of a large suite of genes through quorum sensing signals - N-acyl homoserine lactones (AHLs). In order to investigate the ability of the rhlR/rhlI quorum sensing system in Pseudomonas aeruginosa to express the ß-Galactosidase reporter gene, an engineered E. coli strain EpHL02, was genetically engineered. This engineered E. coli strain EpHL02 responded to the presence of the N-butanoyl homoserine lactone and N-hexanoyl homoserine lactone to express the ß-Galactosidase reporter gene at a concentration limit of 5x10⁻⁸ M. This was also found to be comparable to AHLs extraction from Serratia marcescens H31. Moreover, we examined this ability of this engineered E. coli strain for respond of AHLs from extractions of Pseudomonas aeruginosa ATCC9027. The results demonstrated that the rhlR/rhlI quorum sensing system can express the ß-Galactosidase reporter gene by using the N-butanoyl homoserine lactone, N-hexanoyl homoserine lactone and AHLs from extractions of Serratia marcescens H31 and Pseudomonas aeruginosa ATCC9027 in the engineered E. coli strain EpHL02.

Keywords: N-butanoyl homoserine lactone, C4-HSL, N-hexanoyl homoserine lactone, C6-HSL, Pseudomonas aeruginosa, quorum sensing, Serratia marcescens, ß-galactosidase reporter gene

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1759 The Effect of Nanoclay on the Hydraulic Conductivity of Clayey Sand Soils

Authors: Javad Saeidaskari, Mohammad Hassan Baziar

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Soil structures have been frequently damaged during piping, earthquake and other types of failures. As far as adverse circumstances were developed subsequent to piping or other similar failure types, hydraulic parameters of soil such as hydraulic conductivity should be considered. As a result, acquiring an approach to diminish soil permeability is inevitable. There are many ground improvement methods to reduce seepage, which are classified under soil treatment and stabilization methods. Recently, one of the soil improvement methods is known as nanogeotechnology. This study aims to investigate the influence of Cloisite 30B nanoclay on permeability of compacted clayey sand soils. The samples are prepared by mixing two soil types, including Kaolin clay and Firouzkooh sand, in 1:9 and 1:5 clay:sand (by mass) proportions. In experimental procedure, initially, the optimum water content and maximum dry unit weight of each samples were obtained for compaction. Then, series of permeability tests were conducted by triaxial apparatus on prepared specimens with identical relative density of 95% of maximum dry density and water content of 1% wet of optimum for different weight percentages of nanoclay (1% to 4%). Therefore, in this paper, the effect of time on treated specimen was appraised, as well as two approaches of manual mixing and ball milling were compared to reveal the importance of dispersion issue. The results show that adding nanoclay up to 3%, as its optimum content, causes notable reduction in permeability (1.60e-03 to 5.51e-05 cm/s and 3.32e-04 to 8.44e-07 cm/s in samples with 1:9 and 1:5 mixture proportions, respectively). The hydraulic conductivity of treated clayey sand (1:5 mixture proportion with 3% nanoclay) decreases gradually from 8.44e-07 to 3.00e-07 cm/s within 90 days and then tends to be consistent. The influence of mixing method on permeability results shows that the utilization of ball mill mixing effectively leads to lower values than those of manual mixing, in other words, by adding 3% nanoclay, hydraulic conductivity of specimen declines from 8.44e-07 to 2.00e-07 cm/s. In order to evaluate the interaction between soil particles and, to ensure proper dispersion of nanoparticles through clayey sand mixture, they were magnified by means of scanning electron microscope (SEM). In conclusion, the nanoclay particles in vicinity of moisture can cause soil stabilization to prevent water penetration, which eventually result in lower usage of clay and operation costs.

Keywords: nanoclay, cloisite 30b, clayey sand, hydraulic conductivity

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1758 Investor Sentiment and Satisfaction in Automated Investment: A Sentimental Analysis of Robo-Advisor Platforms

Authors: Vertika Goswami, Gargi Sharma

Abstract:

The rapid evolution of fintech has led to the rise of robo-advisor platforms that utilize artificial intelligence (AI) and machine learning to offer personalized investment solutions efficiently and cost-effectively. This research paper conducts a comprehensive sentiment analysis of investor experiences with these platforms, employing natural language processing (NLP) and sentiment classification techniques. The study investigates investor perceptions, engagement, and satisfaction, identifying key drivers of positive sentiment such as clear communication, low fees, consistent returns, and robust security. Conversely, negative sentiment is linked to issues like inconsistent performance, hidden fees, poor customer support, and a lack of transparency. The analysis reveals that addressing these pain points—through improved transparency, enhanced customer service, and ongoing technological advancements—can significantly boost investor trust and satisfaction. This paper contributes valuable insights into the fields of behavioral finance and fintech innovation, offering actionable recommendations for stakeholders, practitioners, and policymakers. Future research should explore the long-term impact of these factors on investor loyalty, the role of emerging technologies, and the effects of ethical investment choices and regulatory compliance on investor sentiment.

Keywords: artificial intelligence in finance, automated investment, financial technology, investor satisfaction, investor sentiment, robo-advisors, sentimental analysis

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1757 The Prevalence of Obesity among a Huge Sample of 5-20 Years Old Jordanian Children and Adolescents Based on CDC Criteria

Authors: Walid Al-Qerem, Ruba Zumot

Abstract:

Background: The rise of obesity among children and adolescents remains a primary challenge for healthcare providers globally and in the Middle East. The aim of the present study is to determine the prevalence of obesity among 5-20 years old Jordanians based on CDC criteria. Method: A total of 5722 Jordanians (37% males; 63% females) aged 5-20 years data were retrieved from the Jordanian Ministry of Health electronic database (Hakeem). As per the CDC selection criteria, the chosen data pertains exclusively to healthy Jordanian children and adolescents who are medically sound, not suffering from health conditions, and not undergoing any treatments that could hinder normal growth patterns, such as severe infection, chronic kidney disease (CKD), Down’s syndrome, attention deficit hyperactivity disorder, cancer, heart disease, lung disease, cystic fibrosis, Crohn’s disease, type 1 diabetes, hormonal disturbances, any stress-related conditions, hormonal therapy such as corticosteroids, Growth hormones (GHS) or gonadotropin-releasing hormone agonists, insulin, and amphetamines or any other stimulants. In addition, participants with missing or invalid data values for anthropometric measurements were excluded from the study. Weight for age and body mass index for age were analyzed comparatively for Jordanian children and adolescents against the international growth standards. The Z-score for each record was computed based on CDC equations. As per CDC classifications, BMI for age percentiles, values ≥85th and < 95th are classified as overweight, and value at ≥ 95th is classified as obesity. Results: The average age of the evaluated sample was 12.33 ±4.39 years (10.79 ±3.39 for males and 13.23 ± 4.66 for females). The mean weight for males and females were 33.16±14.17 Kg and 133.54±17.17 cm for males, 43.86 ±18.82 Kg, and 142.19±18.35 for females, while for BMI the mean was for boys and girls 17.81±3.88 and 20.52±5.03 respectively. The results indicated that based on CDC criteria, 8.9% of males were classified as children/adolescents with overweight, and 9.7% were classified as children/adolescents with obesity, while in females, 17.8% were classified as children/adolescents with overweight and 10.2% were classified as children/adolescents with obesity. Discussion: The high prevalence of obesity reported in the present study emphasizes the importance of applying different strategies to prevent childhood obesity, including encouraging physical activity, promoting healthier food options, and behavioral changes. Conclusion: The results presented in this study indicated the high prevalence of overweight/obesity among Jordanian adolescents and children, which must be tagged by healthcare planners and providers.

Keywords: CDC, obesity, childhood, Jordan

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1756 Niche Authorities and Social Activism: Interrogating the Activities of Selected Bloggers in Ghana

Authors: Akosua Asantewaa Anane

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Social media and its networking sites have become beneficial to society. With the advent of Web 2.0, many people are becoming technologically savvy and attracted to internet-based activities. With the click of a button, users are now sharing more information on topics, events and issues than before. A new phenomenon in the Ghanaian journalism sphere is the advent of blogger and citizen journalism, some of whom have become niche authorities. Niche authorities have emerged through the habitual and persistent curation of news on specific topics, resulting in the steady growth and emergence of valuable contributions to news sharing. Minimal studies have been conducted on niche authorities and their role in social activism in Ghana. This study, anchored on Cialdini’s Six Principles of Persuasion (reciprocation, consistency, social proof, liking, authority and scarcity), explores the features of niche authorities, their areas of expertise, as well as their authoritative voices in the curation of news stories. Using qualitative content analysis, cyber ethnography and thematic analysis of purposively sampled social media posts of five niche authorities, the study interrogates how these niche authorities employ the six principles of persuasion on their platforms to spark conversations on development, social inclusion and gender-based issues in the country. The study discusses how niche authorities deploy the principles in social activism and further recommends nurturing and mentoring communication strategies to progressively guide the youth to become future niche authorities in news curation and news sharing.

Keywords: social activism, cialdini’s six principles of persuasion, news curation, niche authorities

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1755 Higher Education Internationalisation: The Case of Indonesia

Authors: Agustinus Bandur, Dyah Budiastuti

Abstract:

With the rapid development of information and communication technology (ICT) in globalisation era, higher education (HE) internationalisation has become a worldwide phenomenon. However, even though various studies have been widely published in existing literature, the settings of these studies were taken places in developed countries. Accordingly, the major purpose of this article is to explore the current trends of higher education internationalisation programs with particular reference to identify the benefits and challenges confronted by participating staff and students. For these purposes, ethnographic qualitative study with the usage of NVivo 11 software was applied in coding, analyzing, and visualization of non-numeric data gathered from interviews, videos, web contents, social media, and relevant documents. Purposive sampling technique was applied in this study with a total of ten high-ranked accredited government and private universities in Indonesia. On the basis of thematic and cross-case analyses, this study indicates that while Australia has led other countries in dual-degree programs, partner universities from Japan and Korea have the most frequent collaboration on student exchange programs. Meanwhile, most visiting scholars who have collaborated with the universities in this study came from the US, the UK, Japan, Australia, Netherlands, and China. Other European countries such as Germany, French, and Norway have also conducted joint research with Indonesian universities involved in this study. This study suggests that further supports of government policy and grants are required to overcome the challenges as well as strategic leadership and management roles to achieve high impacts of such programs on higher education quality.

Keywords: higher education, internationalisation, challenges, Indonesia

Procedia PDF Downloads 273
1754 Coalescence of Insulin and Triglyceride/High Density Lipoprotein Cholesterol Ratio for the Derivation of a Laboratory Index to Predict Metabolic Syndrome in Morbid Obese Children

Authors: Orkide Donma, Mustafa M. Donma

Abstract:

Morbid obesity is a health threatening condition particularly in children. Generally, it leads to the development of metabolic syndrome (MetS) characterized by central obesity, elevated fasting blood glucose (FBG), triglyceride (TRG), blood pressure values and suppressed high density lipoprotein cholesterol (HDL-C) levels. However, some ambiguities exist during the diagnosis of MetS in children below 10 years of age. Therefore, clinicians are in the need of some surrogate markers for the laboratory assessment of pediatric MetS. In this study, the aim is to develop an index, which will be more helpful during the evaluation of further risks detected in morbid obese (MO) children. A total of 235 children with normal body mass index (N-BMI), with varying degrees of obesity; overweight (OW), obese (OB), MO as well as MetS participated in this study. The study was approved by the Institutional Ethical Committee. Informed consent forms were obtained from the parents of the children. Obesity states of the children were classified using BMI percentiles adjusted for age and sex. For the purpose, tabulated data prepared by WHO were used. MetS criteria were defined. Systolic and diastolic blood pressure values were measured. Parameters related to glucose and lipid metabolisms were determined. FBG, insulin (INS), HDL-C, TRG concentrations were determined. Diagnostic Obesity Notation Model Assessment Laboratory (DONMALAB) Index [ln TRG/HDL-C*INS] was introduced. Commonly used insulin resistance (IR) indices such as Homeostatic Model Assessment for IR (HOMA-IR) as well as ratios such as TRG/HDL-C, TRG/HDL-C*INS, HDL-C/TRG*INS, TRG/HDL-C*INS/FBG, log, and ln versions of these ratios were calculated. Results were interpreted using statistical package program (SPSS Version 16.0) for Windows. The data were evaluated using appropriate statistical tests. The degree for statistical significance was defined as 0.05. 35 N, 20 OW, 47 OB, 97 MO children and 36 with MetS were investigated. Mean ± SD values of TRG/HDL-C were 1.27 ± 0.69, 1.86 ± 1.08, 2.15 ± 1.22, 2.48 ± 2.35 and 4.61 ± 3.92 for N, OW, OB, MO and MetS children, respectively. Corresponding values for the DONMALAB index were 2.17 ± 1.07, 3.01 ± 0.94, 3.41 ± 0.93, 3.43 ± 1.08 and 4.32 ± 1.00. TRG/HDL-C ratio significantly differed between N and MetS groups. On the other hand, DONMALAB index exhibited statistically significant differences between N and all the other groups except the OW group. This index was capable of discriminating MO children from those with MetS. Statistically significant elevations were detected in MO children with MetS (p < 0.05). Multiple parameters are commonly used during the assessment of MetS. Upon evaluation of the values obtained for N, OW, OB, MO groups and for MO children with MetS, the [ln TRG/HDL-C*INS] value was unique in discriminating children with MetS.

Keywords: children, index, laboratory, metabolic syndrome, obesity

Procedia PDF Downloads 154
1753 The Implementation of an E-Government System in Developing Countries: A Case of Taita Taveta County, Kenya

Authors: Tabitha Mberi, Tirus Wanyoike, Joseph Sevilla

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The use of Information and Communication Technology (ICT) in Government is gradually becoming a major requirement to transform delivery of services to its stakeholders by improving quality of service and efficiency. In Kenya, the devolvement of government from local authorities to county governments has resulted in many counties adopting online revenue collection systems which can be easily accessed by its stakeholders. Strathmore Research and Consortium Centre (SRCC) implemented a revenue collection system in Taita Taveta, a County in coastal Kenya. It consisted of two systems that are integrated; an online system dubbed “CountyPro” for processing county services such as Business Permit applications, General Billing, Property Rates Payments and any other revenue streams from the county. The second part was a Point of Sale(PoS) system used by the county revenue collectors to charge for market fees and vehicle parking fees. This study assesses the success and challenges in adoption of the integrated system. Qualitative and quantitative data collection methods were used to collect data on the adoption of the system with the researcher using focus groups, interviews, and questionnaires to collect data from various users of the system An analysis was carried out and revealed that 87% of the county revenue officers who are situated in county offices describe the system as efficient and has made their work easier in terms of processing of transactions for customers.

Keywords: e-government, counties, information technology, online system, point of sale

Procedia PDF Downloads 253
1752 From CBGB to F21: The Ramone's Band T-Shirt and Its Representations in the Mainstream Culture

Authors: Cláudia Pereira, Lívia Boeschenstein

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This article aims to present an analysis of rock band t-shirts as an element that claims a certain identity in modern-contemporary culture. This work focuses on the study of t-shirts that display the name, related elements and the logo of punk band The Ramones, because of its strong presence in the collective mind along the last decades. As we shall see, it is possible to observe a phenomenon of symbolic transition from the original cultural place of that object. At first, it was a piece of cloth that had been part of a specific subculture and then it became just a generic item diluted by the mainstream. This symbolic transitional phenomenon is significant in many ways and will be discussed furthermore. For the analysis, we begin with a brief introduction to the history of the band, followed by the study about the vintage rock band T-shirts and their meanings. From there, we will turn to a historical contextualization of band T-shirts as a subcultural item and to its redefinition after the appropriation made by the mainstream. To guide this reasoning, it will be used theories about the styles, subcultures and youth culture and about material culture from an anthropological perspective. In addition, we shall see the theories and concepts of social representations in order to understand the ways of using the Ramones’s T-shirt as a representative element of a fashionable style. This T-shirt, after being resignified by the standardization and the massive consumption, no longer symbolizes the punk movement, its behavioral motivations and original policies. Also has little to do with the rage the working class suburbs of London or New York. It seems to be a mute and vague sign of a restricted rebellion, foreseen and framed establishing a stylistic contrast to the designer clothes and good behavior predicted by establishment. It's an item that composes a specific style available on the market, but at the same time is accepted by the mainstream and provides a subcultural association that has some prestige in society. Another perspective is that of resignification loop. As the same way that punk resignified the conventional goods for their own social standards, fashion resignifies what was said to be an object of a subculture and absorbs in their own mass culture standards. Therefore, outsiders to the punk phenomenon wearing Ramones’s T-shirts can be perceived negatively by subcultural members, but at the same time are well received by those who are partially unaware or completely out of subcultural context. For the general public, the stamp of the Ramones’s logo happens to be appreciated as a diffuse allusion to a punk style, since its original meaning has being entirely neutralized.

Keywords: social representations, subcultures, material culture, punk

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1751 Extraction of Scandium (Sc) from an Ore with Functionalized Nanoporous Silicon Adsorbent

Authors: Arezoo Rahmani, Rinez Thapa, Juha-Matti Aalto, Petri Turhanen, Jouko Vepsalainen, Vesa-PekkaLehto, Joakim Riikonen

Abstract:

Production of Scandium (Sc) is a complicated process because Sc is found only in low concentrations in ores and the concentration of Sc is very low compared with other metals. Therefore, utilization of typical extraction processes such as solvent extraction is problematic in scandium extraction. The Adsorption/desorption method can be used, but it is challenging to prepare materials, which have good selectivity, high adsorption capacity, and high stability. Therefore, efficient and environmentally friendly methods for Sc extraction are needed. In this study, the nanoporous composite material was developed for extracting Sc from an Sc ore. The nanoporous composite material offers several advantageous properties such as large surface area, high chemical and mechanical stability, fast diffusion of the metals in the material and possibility to construct a filter out of the material with good flow-through properties. The nanoporous silicon material was produced by first stabilizing the surfaces with a silicon carbide layer and then functionalizing the surface with bisphosphonates that act as metal chelators. The surface area and porosity of the material were characterized by N₂ adsorption and the morphology was studied by scanning electron microscopy (SEM). The bisphosphonate content of the material was studied by thermogravimetric analysis (TGA). The concentration of metal ions in the adsorption/desorption experiments was measured with inductively coupled plasma mass spectrometry (ICP-MS). The maximum capacity of the material was 25 µmol/g Sc at pH=1 and 45 µmol/g Sc at pH=3, obtained from adsorption isotherm. The selectivity of the material towards Sc in artificial solutions containing several metal ions was studied at pH one and pH 3. The result shows good selectivity of the nanoporous composite towards adsorption of Sc. Scandium was less efficiently adsorbed from solution leached from the ore of Sc because of excessive amounts of iron (Fe), aluminum (Al) and titanium (Ti) which disturbed the adsorption process. For example, the concentration of Fe was more than 4500 ppm, while the concentration of Sc was only three ppm, approximately 1500 times lower. Precipitation methods were developed to lower the concentration of the metals other than Sc. Optimal pH for precipitation was found to be pH 4. The concentration of Fe, Al and Ti were decreased by 99, 70, 99.6%, respectively, while the concentration of Sc decreased only 22%. Despite the large reduction in the concentration of other metals, more work is needed to further increase the relative concentration of Sc compared with other metals to efficiently extract it using the developed nanoporous composite material. Nevertheless, the developed material may provide an affordable, efficient and environmentally friendly method to extract Sc on a large scale.

Keywords: adsorption, nanoporous silicon, ore solution, scandium

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1750 The Impact of Cooperative Learning on EFL Learners Oral Performance

Authors: Narimen Hamdini

Abstract:

The mastery of a foreign language often implies adequate speaking competency and communication. However, it has been marked that the Algerian students’ oral performance is affected by the lack of language practice opportunities. The present study aims at investigating the impact of cooperative learning strategies on the learners’ oral performance through integrating some learning strategies in oral expression classes. Thus, a quasi-experimental study with one group pretest-posttest design was conducted. A convenience sample of 27 second-year students from the University of Jijel, Algeria, was taught during three consecutive weeks through cooperative learning activities in conjunction with regular language instruction in oral expression classes. Regarding data collection, the study makes use of students’ questionnaire, a semi-structured interview with the teachers of oral expression, and orally scored pre-posttest. While the students’ questionnaire aims at exploring the learners ‘speaking difficulties and attitudes towards the implementation of the strategy, the semi-structured interview aims at revealing the teachers’ instructional practices and attitudes toward the integration of CL activities. Finally, the oral tests were conducted before and after the intervention to measure the effect of the strategy on the learners’ oral production. The findings showed that the experimental group scored higher in the posttest. Cooperative learning promotes not only the learner’s oral performances, but also motivation and social skills. Consequently, its implementation in the oral expression classes is validated and recommended.

Keywords: cooperative learning, learning, oral performance, teaching

Procedia PDF Downloads 134
1749 An Investigation of Performance Versus Security in Cognitive Radio Networks with Supporting Cloud Platforms

Authors: Kurniawan D. Irianto, Demetres D. Kouvatsos

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The growth of wireless devices affects the availability of limited frequencies or spectrum bands as it has been known that spectrum bands are a natural resource that cannot be added. Many studies about available spectrum have been done and it shows that licensed frequencies are idle most of the time. Cognitive radio is one of the solutions to solve those problems. Cognitive radio is a promising technology that allows the unlicensed users known as secondary users (SUs) to access licensed bands without making interference to licensed users or primary users (PUs). As cloud computing has become popular in recent years, cognitive radio networks (CRNs) can be integrated with cloud platform. One of the important issues in CRNs is security. It becomes a problem since CRNs use radio frequencies as a medium for transmitting and CRNs share the same issues with wireless communication systems. Another critical issue in CRNs is performance. Security has adverse effect to performance and there are trade-offs between them. The goal of this paper is to investigate the performance related to security trade-off in CRNs with supporting cloud platforms. Furthermore, Queuing Network Models with preemptive resume and preemptive repeat identical priority are applied in this project to measure the impact of security to performance in CRNs with or without cloud platform. The generalized exponential (GE) type distribution is used to reflect the bursty inter-arrival and service times at the servers. The results show that the best performance is obtained when security is disable and cloud platform is enable.

Keywords: performance vs. security, cognitive radio networks, cloud platforms, GE-type distribution

Procedia PDF Downloads 350