Search results for: experimental investigation

Authors: Reza Hadjiaghaie Vafaie, Sevda Givtaj

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Automation and control of biological samples and solutions at the microscale is a major advantage for biochemistry analysis and biological diagnostics. Despite the known potential of miniaturization in biochemistry and biomedical applications, comparatively little is known about fluid automation and control at the microscale. Here, we study the electric field effect inside a fluidic channel and proper electrode structures with different patterns proposed to form forward, reversal, and rotational flows inside the channel. The simulation results confirmed that the ac electro-thermal flow is efficient for the control and automation of high-conductive solutions. In this research, the fluid pumping and mixing effects were numerically studied by solving physic-coupled electric, temperature, hydrodynamic, and concentration fields inside a microchannel. From an experimental point of view, the electrode structures are deposited on a silicon substrate and bonded to a PDMS microchannel to form a microfluidic chip. The motions of fluorescent particles in pumping and mixing modes were captured by using a CCD camera. By measuring the frequency response of the fluid and exciting the electrodes with the proper voltage, the fluid motions (including pumping and mixing effects) are observed inside the channel through the CCD camera. Based on the results, there is good agreement between the experimental and simulation studies.

Keywords: microfluidic, nano/micro actuator, AC electrothermal, Reynolds number, micropump, micromixer, microfabrication, mass transfer, biomedical applications

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Authors: Kazuyoshi Mori

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In this paper, we consider the parametrization of Anantharam’s model within the framework of the factorization approach. In the parametrization, we investigate the number of required parameters of Anantharam’s model. We consider single-input single-output systems in this paper. By the investigation, we find three cases that are (1) there exist plants which require only one parameter and (2) two parameters, and (3) the number of parameters is at most three.

Keywords: linear systems, parametrization, coprime factorization, number of parameters

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Authors: S. Chaudhuri, P. A. Bhobe

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Fe₂TiSn is a non-magnetic full Heusler alloy with a small gap (~ 0.07 eV) at the Fermi level. The electronic structure is highly symmetric in both the spin bands and a small percentage of substitution of holes or electrons can push the system towards spin polarization. A stable 100% spin polarization or half-metallicity is very desirable in the field of spintronics, making Fe₂TiSn a highly attractive material. However, this composition suffers from an inherent anti-site disorder between Fe and Ti sites. This paper reports on the method adopted to control the anti-site disorder and the realization of the half-metallic ground state in Fe₂TiSn, achieved by chemical substitution. Here, Sb was substituted at Sn site to obtain Fe₂TiSn₁₋ₓSbₓ compositions with x = 0, 0.1, 0.25, 0.5 and 0.6. All prepared compositions with x ≤ 0.6 exhibit long-range L2₁ ordering and a decrease in Fe – Ti anti-site disorder. The transport and magnetic properties of Fe₂TiSn₁₋ₓSbₓ compositions were investigated as a function of temperature in the range, 5 K to 400 K. Electrical resistivity, magnetization, and Hall voltage measurements were carried out. All the experimental results indicate the presence of the half-metallic ground state in x ≥ 0.25 compositions. However, the value of saturation magnetization is small, indicating the presence of compensated magnetic moments. The observed magnetic moments' values are in close agreement with the Slater–Pauling rule in half-metallic systems. Magnetic interactions in Fe₂TiSn₁₋ₓSbₓ are understood from the local crystal structural perspective using extended X-ray absorption fine structure (EXAFS) spectroscopy. The changes in bond distances extracted from EXAFS analysis can be correlated with the hybridization between constituent atoms and hence the RKKY type magnetic interactions that govern the magnetic ground state of these alloys. To complement the experimental findings, first principle electronic structure calculations were also undertaken. The spin-polarized DOS complies with the experimental results for Fe₂TiSn₁₋ₓSbₓ. Substitution of Sb (an electron excess element) at Sn–site shifts the majority spin band to the lower energy side of Fermi level, thus making the system 100% spin polarized and inducing long-range magnetic order in an otherwise non-magnetic Fe₂TiSn. The present study concludes that a stable half-metallic system can be realized in Fe₂TiSn with ≥ 50% Sb – substitution at Sn – site.

Keywords: antisite disorder, EXAFS, Full Heusler alloy, half metallic ferrimagnetism, RKKY interactions

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Authors: Elachouri Mostafa, Fakchich Jamila, Lazaar Jamila, Elmadmad Mohammed, Marhom Mostafa

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Of course, there has been a great growth in scientific information about medicinal plants in recent decades, but in many ways this has proved poor compensation, because such information is accessible, in practice, only to a very few people and anyway, rather little of it is relevant to problems of management and utilization, as encountered in the field. Active compounds are used in most traditional medicines and play an important role in advancing sustainable rural livelihoods through their conservation, cultivation, propagation, marketing and commercialization. Medicinal herbs are great resources for various pharmaceutical compounds and urgent measures are required to protect these plant species from their natural destruction and disappearance. Indeed, there is a real danger of indigenous Arab medicinal practices and knowledge disappearing altogether, further weakening traditional Arab culture and creating more insecurity, as well as forsaking a resource of inestimable economic and health care importance. As scientific approach, the ethnopharmacological investigation remains the principal way to improve, evaluate, and increase the odds of finding of biologically active compounds derived from medicinal plants. As developing country, belonging to the Mediterranean basin, Morocco country is endowed with resources of medicinal and aromatic plants. These plants have been used over the millennia for human welfare, even today. Besides, Morocco has a large plant biodiversity, in fact, its medicinal flora account more than 4200 species growing on various bioclimatic zones from subhumide to arid and Saharan. Nevertheless, the human and animal pressure resulting from the increase of rural population needs has led to degradation of this patrimony. In this paper, we focus our attention on ethnopharmacological studies carried out in Morocco. The goal of this work is to clarify the importance of herbs as platform for drugs discovery and further development, to highlight the importance of ethnopharmacological study as approach on discovery of natural products in the health care field, and to discuss the limit of ethnopharmacological investigation of drug discovery in Morocco.

Keywords: Morocco, medicinal plants, ethnopharmacology, natural products, drug-discovery

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Authors: Emmanuel U. Unuafe, Oyegoke T. Bukoye, Sandhya Sastry, Yanqing Duan

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Globally, there is increasing interest in project management due to a shortage in infrastructure services supply capability. Hence, it is of utmost importance that organisations understand that choosing a particular project over another is an opportunity cost – tying up the organisations resources. In order to devise constructive ways to bring direction, structure, and oversight to the process of project selection has led to the development of tools and techniques by researchers and practitioners. However, despite the development of various frameworks to assist in the appraisal and selection of government projects, failures are still being recorded with government projects. In developing countries, where frameworks are rarely used, the problems are compounded. To improve the situation, this study will investigate the current practice of construction project selection processes within the Nigeria public sector in order to inform theories of decision making from the perspective of developing nations and project management practice. Unlike other research around construction projects in Nigeria this research concentrate on factors influencing the selection process within the Nigeria public sector, which has received limited study. The authors report the findings of semi-structured interviews of top management in the Nigerian public sector and draw conclusions in terms of decision making extant theory and current practice. Preliminary results from the data analysis show that groups make project selection decisions and this forces sub-optimal decisions due to pressure on time, clashes of interest, lack of standardised framework for selecting projects, lack of accountability and poor leadership. Consequently, because decision maker is usually drawn from different fields, religious beliefs, ethnic group and with different languages. The choice of a project by an individual will be greatly influence by experience, political precedence than by realistic investigation as well as his understanding of the desired outcome of the project, in other words, the individual’s ideology and their level of fairness.

Keywords: factors influencing project selection, public sector construction project selection, projects portfolio selection, strategic decision-making

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Authors: Meltem Betül Sağlam, Halil İbrahim Güler, Aykut Sağlam

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In this work, phthalocyanine compounds containing α-naphtholbenzeinunits have been synthesized. Mutagenicity and DNA binding properties of the compounds were investigated by Salmonella/Microsome Assay and spectrophotometer. According to the results of the preliminary range finding tests, the compounds gave no toxic effect to all tester strain S. typhimurium TA98 and TA100 at doses of 500, 1100, 350, 500 and 750 µg/plate in the presence and absence of S9, respectively. This study showed that all compounds exhibited efficient DNA-binding activity. In conclusion, these non-toxic compounds may be used as effective DNA dyes for molecular biology studies.

Keywords: dye, mutagenicity, phthalocyanine, toxicity

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Authors: Sebastiano Candamano, Antonio Iorfida, Patrizia Frontera, Anastasia Macario, Fortunato Crea

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Alkali-activated materials are promising binders obtained by an alkaline attack on fly-ashes, metakaolin, blast slag among others. In order to guarantee the highest ecological and cost efficiency, a proper selection of precursors and alkaline activators has to be carried out. These choices deeply affect the microstructure, chemistry and performances of this class of materials. Even if, in the last years, several researches have been focused on mix designs and curing conditions, the lack of exhaustive activation models, standardized mix design and curing conditions and an insufficient investigation on shrinkage behavior, efflorescence, additives and durability prevent them from being perceived as an effective and reliable alternative to Portland. The aim of this study is to develop alkali-activated cements mortars containing high amounts of industrial by-products and waste, such as ground granulated blast furnace slag (GGBFS) and ashes obtained from the combustion process of forest biomass in thermal power plants. In particular, the experimental campaign was performed in two steps. In the first step, research was focused on elucidating how the workability, mechanical properties and shrinkage behavior of produced mortars are affected by the type and fraction of each precursor as well as by the composition of the activator solutions. In order to investigate the microstructures and reaction products, SEM and diffractometric analyses have been carried out. In the second step, their durability in harsh environments has been evaluated. Mortars obtained using only GGBFS as binder showed mechanical properties development and shrinkage behavior strictly dependent on SiO2/Na2O molar ratio of the activator solutions. Compressive strengths were in the range of 40-60 MPa after 28 days of curing at ambient temperature. Mortars obtained by partial replacement of GGBFS with metakaolin and forest biomass ash showed lower compressive strengths (≈35 MPa) and shrinkage values when higher amount of ashes were used. By varying the activator solutions and binder composition, compressive strength up to 70 MPa associated with shrinkage values of about 4200 microstrains were measured. Durability tests were conducted to assess the acid and thermal resistance of the different mortars. They all showed good resistance in a solution of 5%wt of H2SO4 also after 60 days of immersion, while they showed a decrease of mechanical properties in the range of 60-90% when exposed to thermal cycles up to 700°C.

Keywords: alkali activated cement, biomass ash, durability, shrinkage, slag

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Authors: M. Salih Taci, N. Tayebi, I. Bozkır

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This paper investigates the operation of a sinusoidal supplied autotransformer on the different states of magnetic polarity of primary and secondary terminals for four different step-up and step-down analytical conditions. In this paper, a new analytical modeling and equations for dot-marked and polarity-based step-up and step-down autotransformer are presented. These models are validated by the simulation of current and voltage waveforms for each state. PSpice environment was used for simulation.

Keywords: autotransformer modeling, autotransformer simulation, step-up autotransformer, step-down autotransformer, polarity

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Authors: Nuri Başpınar, Abdullah Başoğlu, Özgür Özdemir, Çağlayan Özel, FundaTerzi, Özgür Yaman

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Current research is targeting new molecular mechanisms that underlie non-alcoholic fatty liver disease (NAFLD) and associated metabolic disorders like nonalcoholic steatohepatitis (NASH). Forty New Zealand White rabbits have been used and fed a high protein (HP) and energy diet based on grains and containing 11.76 MJ/kg. Boron added to 3 experimental groups’ drinking waters (30 mg boron/L) as boron compounds. Biochemical analysis including boron levels, and nuclear magnetic resonance (NMR) based metabolomics evaluation, and mRNA expression of peroxisome proliferator-activated receptor (PPAR) family were performed. LDL-cholesterol concentrations alone were decreased in all the experimental groups. Boron levels in serum and feces were increased. Content of acetate was in about 2x higher for anhydrous borax group, at least 3x higher for boric acid group. PPARα mRNA expression was significantly decreased in boric acid group. Anhydrous borax attenuated mRNA levels of PPARα, which was further suppressed by boric acid. Boron supplementation decreased the degenerative alterations in hepatocytes. Except borax group other boron groups did not have a pronounced change in tubular epithels of kidney. In conclusion, high protein and energy diet leads hepatocytes’ degenerative changes which can be prevented by boron supplementation. Boric acid seems to precede in this effectiveness.

Keywords: high protein and energy diet, boron, metabolomics, transcriptomic

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Authors: Yang Xiao-Jun, Yu Tian-Hao, Hu Ying-Qi

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Breathing in foreign objects during the operation of the aircraft engine, impurities in the aircraft fuel and products of incomplete combustion can produce deposits on the surface of the turbine blades. These deposits reduce not only the turbine's operating efficiency but also the life of the turbine blades. Based on the small open wind tunnel, the simulation of deposits on the leading edge of the turbine has been carried out in this work. The effect of film cooling on particulate deposition was investigated. Based on the analysis, the adhesive mechanism for the molten pollutants’ reaching to the turbine surface was simulated by matching the Stokes number, TSP (a dimensionless number characterizing particle phase transition) and Biot number of the test facility and that of the real engine. The thickness distribution and growth trend of the deposits have been observed by high power microscope and infrared camera under different temperature of the main flow, the solidification temperature of the particulate objects, and the blowing ratio. The experimental results from the leading edge particulate deposition demonstrate that the thickness of the deposition increases with time until a quasi-stable thickness is reached, showing a striking effect of the blowing ratio on the deposition. Under different blowing ratios, there exists a large difference in the thickness distribution of the deposition, and the deposition is minimal at the specific blow ratio. In addition, the temperature of main flow and the solidification temperature of the particulate have a great influence on the deposition.

Keywords: deposition, experiment, film cooling, leading edge, paraffin particles

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Authors: Dairi Sabri, Mrad Dounia, Djebbar Yassine, Abida Habib

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Food security, which may be ensured by important agricultural production, needs huge amounts of water for irrigation. Recognizing this, the Algerian government made enormous efforts to mobilize water resources. Every drop of water collected, regardless of its origin, is needed to strengthen agricultural production. The present irrigated area in Algeria is about 1 million hectares while the potential agricultural area all over the country exceeds 9 million ha. This clearly shows the need for non-conventional water resources in Algeria, especially treated wastewater reuse. The use of treated wastewater in agricultural irrigation is still at the experimental stage in Algeria. While 20 million hectares worldwide are irrigated with treated wastewater, only 2300 hectares in Algeria are irrigated on an experimental basis in the regions of Setif, Constantine, Mila Telemcen, Tougourt and Boumerdès. The volume of wastewater discharged nationwide is estimated to be around 750 million cubic meters and is expected to exceed 1.5 billion m3 in 2020. An ambitious program of providing treatment facilities has been initiated in this direction to increase the treatment capacity to 2.5 million m3 per day in 2030. In order to optimize the use of this resource, specific research actions interested in defining treated wastewater reuse opportunities and standards are undertaken. The objective of this study is basically to examine the different components of treated wastewater reuse, including standards, treatment processes, agricultural opportunities and potentials as well as technical and economic aspects governing the feasibility of this technology in Algeria based on Geographic Information System (GIS).

Keywords: wastewater reuse, integrated management, irrigation, GIS

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Authors: Miroslava Cuperlovic-Culf, Lipu Wang, Ketty Boyle, Nadine Makley, Ian Burton, Anissa Belkaid, Mohamed Touaibia, Marc E. Surrette

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Metabolic changes are one of the major factors in the development of a variety of diseases in various species. Metabolism of agricultural plants is altered the following infection with pathogens sometimes contributing to resistance. At the same time, pathogens use metabolites for infection and progression. In humans, metabolism is a hallmark of cancer development for example. Quantified metabolomics data combined with other omics or clinical data and analyzed using various unsupervised and supervised methods can lead to better diagnosis and prognosis. It can also provide information about resistance as well as contribute knowledge of compounds significant for disease progression or prevention. In this work, different methods for metabolomics quantification and analysis from Nuclear Magnetic Resonance (NMR) measurements that are used for investigation of disease development in wheat and human cells will be presented. One-dimensional 1H NMR spectra are used extensively for metabolic profiling due to their high reliability, wide range of applicability, speed, trivial sample preparation and low cost. This presentation will describe a new method for metabolite quantification from NMR data that combines alignment of spectra of standards to sample spectra followed by multivariate linear regression optimization of spectra of assigned metabolites to samples’ spectra. Several different alignment methods were tested and multivariate linear regression result has been compared with other quantification methods. Quantified metabolomics data can be analyzed in the variety of ways and we will present different clustering methods used for phenotype determination, network analysis providing knowledge about the relationships between metabolites through metabolic network as well as biomarker selection providing novel markers. These analysis methods have been utilized for the investigation of fusarium head blight resistance in wheat cultivars as well as analysis of the effect of estrogen receptor and carbonic anhydrase activation and inhibition on breast cancer cell metabolism. Metabolic changes in spikelet’s of wheat cultivars FL62R1, Stettler, MuchMore and Sumai3 following fusarium graminearum infection were explored. Extensive 1D 1H and 2D NMR measurements provided information for detailed metabolite assignment and quantification leading to possible metabolic markers discriminating resistance level in wheat subtypes. Quantification data is compared to results obtained using other published methods. Fusarium infection induced metabolic changes in different wheat varieties are discussed in the context of metabolic network and resistance. Quantitative metabolomics has been used for the investigation of the effect of targeted enzyme inhibition in cancer. In this work, the effect of 17 β -estradiol and ferulic acid on metabolism of ER+ breast cancer cells has been compared to their effect on ER- control cells. The effect of the inhibitors of carbonic anhydrase on the observed metabolic changes resulting from ER activation has also been determined. Metabolic profiles were studied using 1D and 2D metabolomic NMR experiments, combined with the identification and quantification of metabolites, and the annotation of the results is provided in the context of biochemical pathways.

Keywords: metabolic biomarkers, metabolic network, metabolomics, multivariate linear regression, NMR quantification, quantified metabolomics, spectral alignment

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Authors: Elizabeth Oyenike Abegunrin

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This study is borne out of the dire need to improve the academic achievement of pupils in social studies. The paper attempted to reconcile the lacuna in teacher’s gender and primary school pupils’ achievement. With specific reference to Social Studies classroom, the aim of this study was to detail how pupils’ achievement is a function of the teacher’s gender as well as to establish the link (if any) between teacher’s gender and pupils’ educational achievement. The significance of this was to create gender-template standard for teachers, school owners, administrators and policy makers to follow in the course of engendering pupils’ achievement in Social Studies. By adopting a quasi-experimental research design, a sample of two hundred pupils was selected across five primary schools in Education District I, Lagos State and assigned to experimental and control groups. A 40-item Gender and Social Studies Achievement Test (GSSAT) was used to obtain data from the pupils. Having analyzed the data collected using Pearson Product Moment Correlation (PPMC), a reliability of 0.78 was obtained. Result revealed that teacher’s gender (male/female) had no significant effect on pupils’ achievement in Social Studies and that there was significant interaction effect of teacher’s commitment devoid of gender on the general education output of pupils in Social Studies. Taken together, the results revealed that there is a high degree correlation between teacher’s commitment and pupils academic achievement in social studies, and not gender-based. The study recommended that social studies teachers should re-assess their classroom instructional strategies and use more innovative instructional methods and techniques that will give the pupils equal opportunities to excel in social studies, rather than their gender differences.

Keywords: gender, academic achievement, social studies, primary school

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Authors: Lauren Kathryn Stretch

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A study was conducted in the underprivileged setting of Nelson Mandela Bay, South Africa in order to monitor the progress of learners whose teachers receive training through the Early Inspiration Training Programme. Through tracking children’s growth & development, the effectiveness of the practitioner-training programme, which focuses on empowering women from underprivileged communities in South Africa, was analyzed. The aim was to identify impact & reach and to assess the effectiveness of this intervention programme through identifying impact on children’s growth and development. A Pre- and Post-Test was administered on about 850 young children in Pre-Grade R and Grade R classes in order to understand children’s ability level & the growth that would be evident as a result of effective teacher training. A pre-test evaluated the level of each child’s abilities, including physical-motor development, language, and speech development, cognitive development including visual perceptual skills, social-emotional development & play development. This was followed by a random selection of the classes of children into experimental and control groups. The experimental group’s teachers (practitioners) received 8-months of training & intervention, as well as mentorship & support. After the 8-month training programme, children from the experimental & control groups underwent post-assessment. The results indicate that the impact of effective practitioner training and enhancing a deep understanding of stimulation on young children, that this understanding is implemented in the classroom, highlighting the areas of growth & development in the children whose teachers received additional training & support, as compared to those who did not receive additional training. Monitoring & Evaluation systems not only track children’s ability levels, but also have a core focus on reporting systems, mentorship and providing ongoing support. As a result of the study, an Online Application (for Apple or Android Devices) was developed which is used to track children’s growth via age-appropriate assessments. The data is then statistically analysed to provide direction for relevant & impactful intervention. The App also focuses on effective reporting strategies, structures, and implementation to support organizations working with young children & maximize on outcomes.

Keywords: early childhood development, developmental child assessments, online application, monitoring and evaluating online

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Authors: Adekunle Adesina, Dorcas Adesina

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This Research investigated the influence of alcohol consumption on attention in Wister albino rats. It was designed to test whether or not alcohol consumption affected visual and auditory attention. The sample of this study comprise of 3males albino rats and 3 females albino rats which were randomly assigned to 3 (male/female each) groups, 1, 2 and 3. The first group which was experimental Group 1 received 4ml of alcohol ingestion with cannula twice daily (morning and evening). The second group which was experimental group 2 received 2ml of alcohol ingestion with cannula twice daily (morning and evening). Third group which was the control group only received water (placebo), all these happened within a period of 2 days. Three hypotheses were advanced and testedf in the study. Hypothesis 1 stated that there will be no significant difference between the response speed of albino rats that consume alcohol and those that consume water on visual attention using 5-CSRTT. This was confirmed (DF (2, 9) = 0.72, P <.05). Hypothesis 2 stated that albino rats who consumed alcohol will perform better than those who consume water on auditory accuracy using 5-CSRTT. This was also tested but not confirmed (DF (2, 9) = 2.10, P< .05). The third hypothesis which stated that female albino rats who consumed alcohol would not perform better than male albino rats who consumed alcohol on auditory accuracy using 5-CSRTT was tested and not confirmed. (DF (4) = 0.17, P < .05). Data was analyzed using one-way ANOVA and T-test for independent measures. It was therefore recommended that government policies and programs should be directed at reducing to the barest minimum the rate of alcohol consumption especially among males as it is detrimental to the human auditory attentional organ.

Keywords: alcohol, attention, influence, rats, Wistar

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Authors: A. O. Glazkov, A. S. Krylova, G. G. Nadareishvili, A. S. Terenchenko, S. I. Yudin

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The topic of the presented materials concerns the design of the exhaust system for a certain internal combustion engine. The exhaust system can be divided into two parts. The first is the engine exhaust manifold, turbocharger, and catalytic converters, which are called “hot part.” The second part is the gas exhaust system, which contains elements exclusively for reducing exhaust noise (mufflers, resonators), the accepted designation of which is the "cold part." The design of the exhaust system from the point of view of acoustics, that is, reducing the exhaust noise to a predetermined level, consists of working on the second part. Modern computer technology and software make it possible to design "cold part" with high accuracy in a given frequency range but with the condition of accurately specifying the input parameters, namely, the amplitude spectrum of the input noise and the acoustic impedance of the noise source in the form of an engine with a "hot part". Getting this data is a difficult problem: high temperatures, high exhaust gas velocities (turbulent flows), and high sound pressure levels (non-linearity mode) do not allow the calculated results to be applied with sufficient accuracy. The aim of this work is to obtain the most reliable acoustic output parameters of an engine with a "hot part" based on a complex of computational and experimental studies. The presented methodology includes several parts. The first part is a finite element simulation of the "cold part" of the exhaust system (taking into account the acoustic impedance of radiation of outlet pipe into open space) with the result in the form of the input impedance of "cold part". The second part is a finite element simulation of the "hot part" of the exhaust system (taking into account acoustic characteristics of catalytic units and geometry of turbocharger) with the result in the form of the input impedance of the "hot part". The next third part of the technique consists of the mathematical processing of the results according to the proposed formula for the convergence of the mathematical series of summation of multiple reflections of the acoustic signal "cold part" - "hot part". This is followed by conducting a set of tests on an engine stand with two high-temperature pressure sensors measuring pulsations in the nozzle between "hot part" and "cold part" of the exhaust system and subsequent processing of test results according to a well-known technique in order to separate the "incident" and "reflected" waves. The final stage consists of the mathematical processing of all calculated and experimental data to obtain a result in the form of a spectrum of the amplitude of the engine noise and its acoustic impedance.

Keywords: acoustic impedance, engine exhaust system, FEM model, test stand

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Authors: Verarisa Ujung

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The Anthropocene – as scientists define as a new geological epoch where human intervention has the dominant influence on the geological, atmospheric, and ecological processes challenges the contemporary discourse in architecture and interior. The dominant influence characterises the incapability to distinguish the notion of nature, subnature, human and non-human. Consequently, living in the Anthropocene demands sensitivity and responsiveness to heighten our sense of the rhythm of transformation and recognition of our environment as a product of natural, social and historical processes. The notion of subnature is particularly emphasised in this paper to investigate the poetic sense of living with subnature. It could be associated with the critical tool for exploring the aesthetic and programmatic implications of subnature on interiority. The ephemeral immaterial attached to subnature promotes the sense of atmospheric delineation of interiority, the very inner significance of body-surface interaction, which central to interior architecture discourse. This would then reflect human’s activities; examine the transformative change, the architectural motion and the traces that left between moments. In this way, engaging the notion of subnature enable us to better understand the critical subject on interiority and might provide an in-depth study on interior architecture. Incorporating the exploration on the form, materiality, and pattern of subnature, this research seeks to grasp the inner significance of micro to macro approaches so that the future of interior might be compelled to depend more on the investigation and development of responsive environment. To reflect upon the form, materiality and intensity of subnature that specifically characterized by the natural, social and historical processes, this research examines a volcanic land, White Island/Whakaari, New Zealand as the chosen site of investigation. Emitting various forms and intensities of subnatures - smokes, mud, sulphur gas, this volcanic land also open to the new inhabitation within the sulphur factory ruins that reflects human’s past occupation. In this way, temporal and natural selected manifestations of materiality, artefact, and performance can be traced out and might reveal the meaningful relations among space, inhabitation, and well-being of inhabitants in the Anthropocene.

Keywords: anthropocene, body, intensification, intensity, interior architecture, subnature, surface

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Authors: Li-Hua Luu, Alexis Doghmane, Abbas Farhat, Mohammad Sanayei, Pierre Philippe, Pablo Cuellar

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Suction buckets are promising innovative foundations for offshore wind turbines. They generally feature the shape of an inverted bucket and rely on a suction system as a driving agent for their installation into the seabed. Water is pumped out of the buckets that are initially placed to rest on the seabed, creating a net pressure difference across the lid that generates a seepage flow, lowers the soil resistance below the foundation skirt, and drives them effectively into the seabed. The stability of the suction mechanism as well as the possibility of a piping failure (i.e., localized fluidization within the internal soil plug) during their installation are some of the key questions that remain open. The present work deals with an experimental study of localized fluidization by suction within a fixed bucket partially embedded into a submerged artificial soil made of spherical beads. The transient process, from the onset of granular motion until reaching a stationary regime for the fluidization at the embedded bucket wall, is recorded using the combined optical techniques of planar laser-induced fluorescence and refractive index matching. To conduct a systematic study of the piping threshold for the seepage flow, we vary the beads size, the suction pressure, and the initial depth for the bucket. This experimental modelling, by dealing with erosion-related phenomena from a micromechanical perspective, shall provide qualitative scenarios for the local processes at work which are missing in the offshore practice so far.

Keywords: fluidization, micromechanical approach, offshore foundations, suction bucket

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Authors: Gokhan Egilmez, Erika Hatfield, Julie Turner

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In this study, we investigated the impacts of service-learning integration on an undergraduate level business analytics course from multiple perspectives, including academic proficiency, community awareness, engagement, social responsibility, and reflection. We assessed the impact of the service-learning experience by using a survey developed primarily based on the literature review and secondarily on an ad hoc group of researchers. Then, we implemented the survey in two sections, where one of the sections was a control group. We compared the results of the empirical survey visually and statistically.

Keywords: business analytics, service learning, experiential education, statistical analysis, survey research

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Authors: Mitchell J. Baum, Badin Gibbes, Greg Collecutt

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This study details a three-dimensional field-scale numerical investigation conducted for the Gold Coast Desalination Plant (GCDP) offshore multiport brine diffuser. Quantitative assessment of diffuser performance with regard to trajectory, dilution and mapping of seafloor concentration distributions was conducted for 100% plant operation. The quasi-steady Computational Fluid Dynamics (CFD) simulations were performed using the Reynolds averaged Navier-Stokes equations with a k-ω shear stress transport turbulence closure scheme. The study compliments a field investigation, which measured brine plume characteristics under similar conditions. CFD models used an iterative mesh in a domain with dimensions 400 m long, 200 m wide and an average depth of 24.2 m. Acoustic Doppler current profiler measurements conducted in the companion field study exhibited considerable variability over the water column. The effect of this vertical variability on simulated discharge outcomes was examined. Seafloor slope was also accommodated into the model. Ambient currents varied predominantly in the longshore direction – perpendicular to the diffuser structure. Under these conditions, the alternating port orientation of the GCDP diffuser resulted in simultaneous subjection to co-propagating and counter-propagating ambient regimes. Results from quiescent ambient simulations suggest broad agreement with empirical scaling arguments traditionally employed in design and regulatory assessments. Simulated dynamic ambient regimes showed the influence of ambient crossflow upon jet trajectory, dilution and seafloor concentration is significant. The effect of ambient flow structure and the subsequent influence on jet dynamics is discussed, along with the implications for using these different simulation approaches to inform regulatory decisions.

Keywords: computational fluid dynamics, desalination, field-scale simulation, multiport brine diffuser, negatively buoyant jet

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Authors: Diaa Ahmed Mohamed Ahmedien

Abstract:

Nowadays, it cannot be denied that the most important interactive arts trends have appeared as a result of significant scientific mutations in the modern sciences, and holographic art is not an exception, where it is considered as a one of the most important major contemporary interactive arts trends in visual arts. Holographic technique had been evoked through the modern physics application in late 1940s, for the improvement of the quality of electron microscope images by Denis Gabor, until it had arrived to Margaret Benyon’s art exhibitions, and then it passed through a lot of procedures to enhance its quality and artistic applications technically and visually more over 70 years in visual arts. As a modest extension to these great efforts, this research aimed to invoke extraordinary attempt to enroll sample of normal people in Egyptian community in holographic recording program to record their appreciated objects or antiques, therefore examine their abilities to interact with modern techniques in visual communication arts. So this research tried to answer to main three questions: 'can we use the analog holographic techniques to unleash new theoretical and practical knowledge in interactive arts for public in Egyptian community?', 'to what extent holographic art can be familiar with public and make them able to produce interactive artistic samples?', 'are there possibilities to build holographic interactive program for normal people which lead them to enhance their understanding to visual communication in public and, be aware of interactive arts trends?' This research was depending in its first part on experimental methods, where it conducted in Laser lab at Cairo University, using Nd: Yag Laser 532 nm, and holographic optical layout, with selected samples of Egyptian people that they have been asked to record their appreciated object, after they had already learned recording methods, and in its second part on a lot of discussion panel had conducted to discuss the result and how participants felt towards their holographic artistic products through survey, questionnaires, take notes and critiquing holographic artworks. Our practical experiments and final discussions have already lead us to say that this experimental research was able to make most of participants pass through paradigm shift in their visual and conceptual experiences towards more interaction with contemporary visual arts trends, as an attempt to emphasize to the role of mature relationship between the art, science and technology, to spread interactive arts out in our community through the latest scientific and artistic mutations around the world and the role of this relationship in our societies particularly with those who have never been enrolled in practical arts programs before.

Keywords: Egyptian community, holographic art, laser art, visual art

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Authors: Otokiti Mojeed Jimoh

Abstract:

This work investigates the possibility of using recycled polyethylene LDPE as a base polymer in production of different products (shoe sole, foot mat, and many more) using carbon black as a filler to improve its mechanical properties, like hardness, tensile stress properties and elongation at break properties, from the result so far gotten there is a possibility that there is an increase in the mechanical properties of the sample compare to natural rubber sample.

Keywords: recycled polyethylene, base polymer, hardness, stress properties

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Authors: Sally A. El Awdan, Gehad A. Abdel Jaleel, Dalia O Saleh, Manal Badawi

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Background: Diabetes is a metabolic disease that affects a wide range of people worldwide and results in serious complications. Streptozotocin (STZ) causes selective cytotoxicity in the pancreatic β-cell, and it has been extensively used to induce diabetes mellitus in rats. The present study investigated the effects of diosmin and chrysin alone or in combination with each other on glucose level and on liver in STZ diabetic rats. Methods: In this study, rats were divided into six experimental groups (normal, untreated STZ-diabetic (60 mg/kg B.W., IP), treated STZ-diabetic with glycazide (10 mg/kg B.W, oral), treated STZ-diabetic with diosmin (100 mg/kg B. W., oral), treated STZ-diabetic with chrysin (80 mg/kg B.W., oral), treated STZ-diabetic with diosmin (50 mg/kg B.W, oral) + chrysin (40 mg/kg B.W., oral). After 2 weeks blood samples were withdrawn and glucose was measured. Animals were anaesthetized with an intraperitoneal injection of sodium pentobarbital (60 mg/kg), and sacrificed for dissecting liver. Results: Throughout the experimental period, all treatments significantly (P<0.05) lowered serum glucose, AST, ALT, triglyceride, cholesterol, IL-6, TNF-α and IL-1β. Moreover, the treated diabetic rats showed higher levels of reduced glutathione (P<0.05) in the liver compared to the diabetic control rats and inhibited diabetes-induced elevation in the levels of malondialdehyde in liver. The results of this study clearly demonstrated that diosmin and chrysin possess several treatment-oriented properties, including the control of hyperglycemia, antioxidant effects and anti-inflammatory effects. Conclusion: Considering these observations, it appears that diosmin and chrysin may be a useful supplement to delay the developmentof diabetes and its complications.

Keywords: diabetes, streptozocin, chrysin, rat, diosmin, cytokines

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Authors: Olivier Delage, Hassan Bencherif, Alain Bourdier

Abstract:

Signal decomposition approaches represent an important step in time series analysis, providing useful knowledge and insight into the data and underlying dynamics characteristics while also facilitating tasks such as noise removal and feature extraction. As most of observational time series are nonlinear and nonstationary, resulting of several physical processes interaction at different time scales, experimental time series have fluctuations at all time scales and requires the development of specific signal decomposition techniques. Most commonly used techniques are data driven, enabling to obtain well-behaved signal components without making any prior-assumptions on input data. Among the most popular time series decomposition techniques, most cited in the literature, are the empirical mode decomposition and its variants, the empirical wavelet transform and singular spectrum analysis. With increasing popularity and utility of these methods in wide ranging applications, it is imperative to gain a good understanding and insight into the operation of these algorithms. In this work, we describe all of the techniques mentioned above as well as their ability to denoise signals, to capture trends, to identify components corresponding to the physical processes involved in the evolution of the observed system and deduce the dimensionality of the underlying dynamics. Results obtained with all of these methods on experimental total ozone columns and rainfall time series will be discussed and compared

Keywords: denoising, empirical mode decomposition, singular spectrum analysis, time series, underlying dynamics, wavelet analysis

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Authors: Arefeh Sabzipour

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In the present work, the effect of Lepidium meyenii on viability, motility, and sperm morphology in the treatment of infertility of adult male Wistar rats was evaluated. 21 male Wistar rats were adopted, fed and brought up in the same conditions to reach the weight of 230±5 g. after that, they were randomly divided into three groups, including two experimental groups and one control group, each group consisted of 7 rates. Lepidium meyenii was extracted and pulverized. Mice in the control group were treated with distilled water, and experimental groups were gavage with alcoholic juice extracted from Lepidium meyenii once a day for 10 consecutive days. After rates were killed, the testes were isolated. Different parameters includes semen volume in mice, sperm count, sperm motility, morphology, and viability, were evaluated. The results shows that sperm motility and sperm survival indices were significantly different between groups, and sperm count and sperm morphology indices were not significantly different. Sperm motility index in intervention group 1 was equal to 77.00±2.499 and was significantly higher than the one in intervention group two (70.14±3.579, P=0.018) and control group (69.43 ±7.323, P=0.018). Sperm survival index was 91.14 ± 2.410 in intervention group 1, 79.43± 5.062 in intervention group 2, and 76.71.6.651 in the control group (P<0.001). Based on the results of the present study, Lepidium meyenii had great effect on improving sperm indices of mice, especially sperm motility index and sperm survival index. Sperm count index and sperm morphology index, although increased, were not statistically significant.

Keywords: infertility, lepidium, sperm morphology, sperm survival

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Authors: Min Fang, Jiaxi Yang

Abstract:

Monetary policy could be less effective at stimulating investment during periods of elevated volatility than during normal times. In this paper, we argue that elevated volatility leads to a decrease in extensive margin investment incentive so that nominal stimulus generates less aggregate investment. To do this, we first empirically document that high volatility weakens firms’ investment responses to monetary stimulus. Such effects depend on the lumpiness nature of the firm-level investment. The findings are that the channel exists for all of the physical investment, innovation investment, and organization investment.

Keywords: investment, irreversibility, volatility, uncertainty, firm heterogeneity, monetary policy

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Authors: SeungHee Ryu, Junil Moon

Abstract:

The magnetic resonance wireless power transfer system is widely researched due to its benefits such as spatial freedom. In this paper, power transmitting unit and power receiving unit of wireless battery charger for mobile devices is presented. Power transmitting unit efficiency is measured under different test conditions with power receiving units.

Keywords: magnetic resonance coupling, wireless power transfer, power transfer efficiency.

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Authors: Erfan Niazi, Marianne Fenech

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Red Blood Cells (RBCs) or erythrocytes tend to form chain-like aggregates under low shear rate called rouleaux. This is a reversible process and rouleaux disaggregate in high shear rates. Therefore, RBCs aggregation occurs in the microcirculation where low shear rates are present but does not occur under normal physiological conditions in large arteries. Numerical modeling of RBCs interactions is fundamental in analytical models of a blood flow in microcirculation. Population Balance Modeling (PBM) is particularly useful for studying problems where particles agglomerate and break in a two phase flow systems to find flow characteristics. In this method, the elementary particles lose their individual identity due to continuous destructions and recreations by break-up and agglomeration. The aim of this study is to find RBCs aggregation in a dynamic situation. Simplified PBM was used previously to find the aggregation rate on a static observation of the RBCs aggregation in a drop of blood under the microscope. To find aggregation rate in a dynamic situation we propose an experimental set up testing RBCs sedimentation. In this test, RBCs interact and aggregate to form rouleaux. In this configuration, disaggregation can be neglected due to low shear stress. A high-speed camera is used to acquire video-microscopic pictures of the process. The sizes of the aggregates and velocity of sedimentation are extracted using an image processing techniques. Based on the data collection from 5 healthy human blood samples, the aggregation rate was estimated as 2.7x10³(±0.3 x10³) 1/s.

Keywords: red blood cell, rouleaux, microfluidics, image processing, population balance modeling

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Authors: Cheng Sheng, Yuemin Zhao, Chenlong Duan

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Air dense medium fluidized bed is a typical application of fluidization techniques for coal particle separation in arid areas, where it is costly to implement wet coal preparation technologies. In the last three decades, air dense medium fluidized bed, as an efficient dry coal separation technique, has been studied in many aspects, including energy and mass transfer, hydrodynamics, bubbling behaviors, etc. Despite numerous researches have been published, the fluidization features, especially dual dense medium fluidization features have been rarely reported. In dual dense medium fluidized beds, different combinations of different dense mediums play a significant role in fluidization quality variation, thus influencing coal separation efficiency. Moreover, to what extent different dense mediums mix and to what extent the two-component particulate mixture affects the fluidization performance and quality have been in suspense. The proposed work attempts to reveal underlying mechanisms of generation and evolution of two-component particulate mixture in the fluidization process. Based on computational fluid dynamics methods and discrete particle modelling, movement and evolution of dual dense mediums in air dense medium fluidized bed have been simulated. Dual dense medium fluidization experiments have been conducted. Electrical capacitance tomography was employed to investigate the distribution of two-component mixture in experiments. Underlying mechanisms involving two-component particulate fluidization are projected to be demonstrated with the analysis and comparison of simulation and experimental results.

Keywords: air dense medium fluidized bed, particle separation, computational fluid dynamics, discrete particle modelling

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Authors: Nabila Mohamed, Santiago Aparicio, Bahman Tohidi, Mert Atilhan

Abstract:

Qatar's one of the biggest problem in processing its natural resource, which is natural gas, is the often occurring blockage in the pipelines caused due to uncontrolled gas hydrate formation in the pipelines. Several millions of dollars are being spent at the process site to dehydrate the blockage safely by using chemical inhibitors. We aim to establish national database, which addresses the physical conditions that promotes Qatari natural gas to form gas hydrates in the pipelines. Moreover, we aim to design and test novel hydrate inhibitors that are suitable for Qatari natural gas and its processing facilities. From these perspectives we are aiming to provide more effective and sustainable reservoir utilization and processing of Qatari natural gas. In this work, we present the initial findings of a QNRF funded project, which deals with the natural gas hydrate formation characteristics of Qatari type gas in both experimental (PVTx) and computational (molecular simulations) methods. We present the data from the two fully automated apparatus: a gas hydrate autoclave and a rocking cell. Hydrate equilibrium curves including growth/dissociation conditions for multi-component systems for several gas mixtures that represent Qatari type natural gas with and without the presence of well known kinetic and thermodynamic hydrate inhibitors. Ionic liquids were designed and used for testing their inhibition performance and their DFT and molecular modeling simulation results were also obtained and compared with the experimental results. Results showed significant performance of ionic liquids with up to 0.5 % in volume with up to 2 to 4 0C inhibition at high pressures.

Keywords: gas hydrates, natural gas, ionic liquids, inhibition, thermodynamic inhibitors, kinetic inhibitors

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