Search results for: formation and concentration and growth of TiC
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 13098

Search results for: formation and concentration and growth of TiC

5328 Study of Pipes Scaling of Purified Wastewater Intended for the Irrigation of Agadir Golf Grass

Authors: A. Driouiche, S. Mohareb, A. Hadfi

Abstract:

In Morocco’s Agadir region, the reuse of treated wastewater for irrigation of green spaces has faced the problem of scaling of the pipes of these waters. This research paper aims at studying the phenomenon of scaling caused by the treated wastewater from the Mzar sewage treatment plant. These waters are used in the irrigation of golf turf for the Ocean Golf Resort. Ocean Golf, located about 10 km from the center of the city of Agadir, is one of the most important recreation centers in Morocco. The course is a Belt Collins design with 27 holes, and is quite open with deep challenging bunkers. The formation of solid deposits in the irrigation systems has led to a decrease in their lifetime and, consequently, a loss of load and performance. Thus, the sprinklers used in golf turf irrigation are plugged in the first weeks of operation. To study this phenomenon, the wastewater used for the irrigation of the golf turf was taken and analyzed at various points, and also samples of scale formed in the circuits of the passage of these waters were characterized. This characterization of the scale was performed by X-ray fluorescence spectrometry, X-ray diffraction (XRD), thermogravimetric analysis (TGA), differential thermal analysis (DTA), and scanning electron microscopy (SEM). The results of the physicochemical analysis of the waters show that they are full of bicarbonates (653 mg/L), chloride (478 mg/L), nitrate (412 mg/L), sodium (425 mg/L) and calcium (199mg/L). Their pH is slightly alkaline. The analysis of the scale reveals that it is rich in calcium and phosphorus. It is formed of calcium carbonate (CaCO₃), silica (SiO₂), calcium silicate (Ca₂SiO₄), hydroxylapatite (Ca₁₀P₆O₂₆), calcium carbonate and phosphate (Ca₁₀(PO₄) 6CO₃) and silicate calcium and magnesium (Ca₅MgSi₃O₁₂).

Keywords: Agadir, irrigation, scaling water, wastewater

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5327 The Role of Entrepreneurship Education in Enhancing Self-Employment: Students' Perspective

Authors: Stanley Fore, Gaetan Ngabonziza

Abstract:

In spite of the need for skilled labour in South Africa, tertiary education graduates are increasingly faced with unemployment, which poses a serious obstacle to the economic growth of the country. This paper is an outcome of the study that investigated students’ perceptions on the role of entrepreneurship education in enhancing graduates’ self-employment. The study was descriptive in nature and used a survey questionnaire to answer questions pertaining to the extent to which entrepreneurship education is important in enhancing self-employment endeavours. Collected data were analysed using of the statistical software for social science (SPSS) for descriptive statistics in the form of tables and charts. The study found that entrepreneurship education is critical in providing knowledge and skills that are required to succeed in self-employment. As one module of entrepreneurship does not ensure self-employment orientation or more positive expectations about entrepreneurial abilities and careers, this study suggests that students, irrespective of their field of study, should be given entrepreneurship modules in every academic year. This will help in reminding them that their success does not solely rely on their ability to find a better-paying employment but also on their ability to employ themselves.

Keywords: entrepreneurship, education, self-employment, students

Procedia PDF Downloads 239
5326 Design and Development of Power Sources for Plasma Actuators to Control Flow Separation

Authors: Himanshu J. Bahirat, Apoorva S. Janawlekar

Abstract:

Plasma actuators are essential for aerodynamic flow separation control due to their lack of mechanical parts, lightweight, and high response frequency, which have numerous applications in hypersonic or supersonic aircraft. The working of these actuators is based on the formation of a low-temperature plasma between a pair of parallel electrodes by the application of a high-voltage AC signal across the electrodes, after which air molecules from the air surrounding the electrodes are ionized and accelerated through the electric field. The high-frequency operation is required in dielectric discharge barriers to ensure plasma stability. To carry out flow separation control in a hypersonic flow, the optimal design and construction of a power supply to generate dielectric barrier discharges is carried out in this paper. In this paper, it is aspired to construct a simplified circuit topology to emulate the dielectric barrier discharge and study its various frequency responses. The power supply can generate high voltage pulses up to 20kV at the repetitive frequency range of 20-50kHz with an input power of 500W. The power supply has been designed to be short circuit proof and can endure variable plasma load conditions. Its general outline is to charge a capacitor through a half-bridge converter and then later discharge it through a step-up transformer at a high frequency in order to generate high voltage pulses. After simulating the circuit, the PCB design and, eventually, lab tests are carried out to study its effectiveness in controlling flow separation.

Keywords: aircraft propulsion, dielectric barrier discharge, flow separation control, power source

Procedia PDF Downloads 116
5325 Analyzing the Investment Decision and Financing Method of the French Small and Medium-Sized Enterprises

Authors: Eliane Abdo, Olivier Colot

Abstract:

SMEs are always considered as a national priority due to their contribution to job creation, innovation and growth. Once the start-up phase is crossed with encouraging results, the company enters the phase of growth. In order to improve its competitiveness, maintain and increase its market share, the company is in the necessity even the obligation to develop its tangible and intangible investments. SMEs are generally closed companies with special and critical financial situation, limited resources and difficulty to access the capital markets; their shareholders are always living in a conflict between their independence and their need to increase capital that leads to the entry of new shareholder. The capital structure was always considered the core of research in corporate finance; moreover, the financial crisis and its repercussions on the credit’s availability, especially for SMEs make SME financing a hot topic. On the other hand, financial theories do not provide answers to capital structure’s questions; they offer tools and mode of financing that are more accessible to larger companies. Yet, SME’s capital structure can’t be independent of their governance structure. The classic financial theory supposes independence between the investment decision and the financing decision. Thus, investment determines the volume of funding, but not the split between internal or external funds. In this context, we find interesting to study the hypothesis that SMEs respond positively to the financial theories applied to large firms and to check if they are constrained by conventional solutions used by large companies. In this context, this research focuses on the analysis of the resource’s structure of SME in parallel with their investments’ structure, in order to highlight a link between their assets and liabilities structure. We founded our conceptual model based on two main theoretical frameworks: the Pecking order theory, and the Trade Off theory taking into consideration the SME’s characteristics. Our data were generated from DIANE database. Five hypotheses were tested via a panel regression to understand the type of dependence between the financing methods of 3,244 French SMEs and the development of their investment over a period of 10 years (2007-2016). The results show dependence between equity and internal financing in case of intangible investments development. Moreover, this type of business is constraint to financial debts since the guarantees provided are not sufficient to meet the banks' requirements. However, for tangible investments development, SMEs count sequentially on internal financing, bank borrowing, and new shares issuance or hybrid financing. This is compliant to the Pecking Order Theory. We, therefore, conclude that unlisted SMEs incur more financial debts to finance their tangible investments more than their intangible. However, they always prefer internal financing as a first choice. This seems to be confirmed by the assumption that the profitability of the company is negatively related to the increase of the financial debt. Thus, the Pecking Order Theory predictions seem to be the most plausible. Consequently, SMEs primarily rely on self-financing and then go, into debt as a priority to finance their financial deficit.

Keywords: capital structure, investments, life cycle, pecking order theory, trade off theory

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5324 Recovery of Wastewater Treated of Boumerdes Step for Irrigation

Authors: N. Ouslimani, M. T. Abadlia, S. Yakoub, F. Tebbani

Abstract:

Water has always been synonymous with life and growth. Blue gold is first essential to the survival of the human being whose body consists of more than 65% with the development of industrialization and consumption patterns; volumes of wastewater discharges have increased considerably whether industrial or domestic, waste water must be purified before discharge. Treatment, therefore, aims to reduce the pollution load which contain. The resources in Algeria are limited and unevenly distributed. Thus, to meet all the water needs of the country and to preserve the waters of good quality drinking water supply, one solution would be to use them according to their quality and to irrigate crops for the food or be directed to the irrigation of green areas or sports complex. The purification performance of this STEP has been established since the pH analyzed pollution criteria (7.36) and temperature (16°C), MES (10 mg / l), electrical conductivity (1122 / µs / cm), DBO5 (6mg / l), DCO (15mg / l) meet the discharge standards. Arguably the purified water discharged out of the boumerdes STEP comply with Algerian regulations and can be reused in agriculture. COD biodegradability of the coefficient / BOD5 is 2.5 (less than 3) indicates that of the effluent are biodegradable hence their urban origin.

Keywords: irrigation, recovery, treated, wastewater

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5323 Identification and Isolation of E. Coli O₁₅₇:H₇ From Water and Wastewater of Shahrood and Neka Cities by PCR Technique

Authors: Aliasghar Golmohammadian, Sona Rostampour Yasouri

Abstract:

One of the most important intestinal pathogenic strains is E. coli O₁₅₇:H₇. This pathogenic bacterium is transmitted to humans through water and food. E. coli O₁₅₇:H₇ is the main cause of Hemorrhagic colitis (HC), Hemolytic Uremic Syndrome (HUS), Thrombotic Thrombocytopenic Purpura (TTP) and in some cases death. Since E. coli O₁₅₇:H₇ can be transmitted through the consumption of different foods, including vegetables, agricultural products, and fresh dairy products, this study aims to identify and isolate E. coli O₁₅₇:H₇ from wastewater by PCR technique. One hundred twenty samples of water and wastewater were collected by Falcom Sterile from Shahrood and Neka cities. The samples were checked for colony formation after appropriate centrifugation and cultivation in the specific medium of Sorbitol MacConkey Agar (SMAC) and other diagnostic media of E. coli O₁₅₇:H₇. Also, the plates were observed macroscopically and microscopically. Then, the necessary phenotypic tests were performed on the colonies, and finally, after DNA extraction, the PCR technique was performed with specific primers related to rfbE and stx2 genes. The number of 5 samples (6%) out of all the samples examined were determined positive by PCR technique with observing the bands related to the mentioned genes on the agarose gel electrophoresis. PCR is a fast and accurate method to identify the bacteria E. coli O₁₅₇:H₇. Considering that E. coli bacteria is a resistant bacteria and survives in water and food for weeks and months, the PCR technique can provide the possibility of quick detection of contaminated water. Moreover, it helps people in the community control and prevent the transfer of bacteria to healthy and underground water and agricultural and even dairy products.

Keywords: E. coli O₁₅₇:H₇, PCR, water, wastewater

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5322 Tryptophan and Its Derivative Oxidation via Heme-Dioxygenase Enzyme

Authors: Ali Bahri Lubis

Abstract:

Tryptophan oxidation by Heme-dioxygenase enzyme is the initial rate-limiting step in the kynurenine pathway, which leads to the formation of NADH and dangerous metabolites, implicating several severe diseases such as Parkinson’s Disease, Huntington's Disease, poliomyelitis and cataract. This oxidation, generally, allows tryptophan to convert to N-Formylkynurenine (NFK). Observing the catalytic mechanism of Heme dioxygenase in tryptophan oxidation has been a debatably scientific interest since no one has yet proven the mechanism obviously. In this research we have attempted to prove mechanistic steps of tryptophan oxidation via human indoleamine dioxygenase (h-IDO) utilising various substrates: L-tryptophan, L-tryptophan (indole-ring-2-¹³C), L-fully-labelled¹³C-tryptophan, L-N-methyl-tryptophan, L-tryptophanol and 2-amino-3-(benzo(b)thiophene-3-yl) propanoic acid. All enzyme assay experiments were measured using a UV-Vis spectrophotometer, LC-MS, 1H-NMR and HSQC. We also successfully synthesised enzyme products as our control in NMR measurements. The result exhibited that all substrates produced N-formyl kynurenine (NFK), and a side, the minor product of hydroxypyrrolloindoleamine carboxylic acid (HPIC) in cis and trans isomer, except 1-methyl tryptophan only generating cis HPIC. Interestingly, L- tryptophanol was oxidised to form HPIC derivative as a major product and 5-hydroxy tryptophan was converted to NFK derivative instead without any HPIC derivative. The bizarre result of oxidation underwent in 2-amino-3-(benzo(b)thiophene-3-yl) propanoic acid, which produced epoxide cyclic. Those phenomena have been explainable in our research based on the proposed mechanism of how tryptophan is oxidised by human indoleamine dioxygenase.

Keywords: tryptophan oxidation, heme-dioxygenases, human indoleamine dioxygenases, N-formylkynurenine, hydroxypyrroloindoleamine carboxylic acid

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5321 A Conceptual Approach for Evaluating the Urban Renewal Process

Authors: Muge Unal, Ahmet Cilek

Abstract:

Urban identity, having a dynamic characteristic spatial and semantic aspects, is a phenomenon in an ever-changing. Urban identity formation includes not only a process of physical nature but also development and change processes that take place in the political, economic, social and cultural values, whether national and international level. Although the concept of urban transformation is basically regarded as the spatial transformation; in fact, it reveals a holistic perspective and transformation based on dialectical relationship existing between the spatial and social relationship. For this reason, urban renewal needs to address as not only spatial but also the impact of spatial transformation on social, cultural and economic. Implementation tools used in the perception of urban transformation are varied concepts such as urban renewal, urban resettlement, urban rehabilitation, urban redevelopment, and urban revitalization. The phenomenon of urban transformation begins with the Industrial Revolution. Until the 1980s, it was interpreted as reconsidering physical fossil on urban environment factor like occurring in rapid urbanization, changing in the spatial structure of the city, concentrating of the population in urban areas. However, after the 1980s, it has resided in a conceptual structure which requires to be addressed physical, economic, social, technological and integrity of information. In conclusion, urban transformation, when it enter the literature as a practice of planning, has been up to date in terms of the conceptual structure and content and also hasn’t remained behind converting itself. Urban transformation still maintains its simplest expression, while it transforms so fast converts the contents. In this study, the relationship between urban design and components of urban transformation were discussed with strategies used as a place in the historical process of urban transformation besides a general evaluation of the concept of urban renewal.

Keywords: conceptual approach, urban identity, urban regeneration, urban renewal

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5320 Qatari Licensure System: Giving Voice to Educators at Government-Funded Schools

Authors: Abdullah Abu-Tineh, Hissa Sadiq, Fatma Al-Mutawah, Youmen Chabaan

Abstract:

The current study examined the experiences of educators in Qatar with the licensure process currently implemented at government schools. Using a survey study design, a total of 1,669 participants expressed their perceptions on the strengths and weaknesses of the licensure system, the professional standards, and the professional portfolio. Findings included participants’ beliefs on the importance of the licensure system in improving their performance, the necessity of using the professional standards as tools for professional growth and development, the importance of refining the professional portfolio for authenticity and reliability, and the inclusion of multiple sources of evidence, such as classroom observations, interviews, student learning outcomes, and surveys. Documenting teachers’ and school leaders’ voices was fundamental in finding ways to successfully drive future developments of the licensure system. The findings may also provide implications for other countries interested in developing or refining their own appraisal systems.

Keywords: licensure system, educator voice, professional standards, professional portfolio

Procedia PDF Downloads 186
5319 Comparative Literature, Postcolonialism and the “African World” in Wole Soyinka’s Myth, Literature and the African World

Authors: Karen de Andrade

Abstract:

Literature is generally understood as an aesthetic creation, an artistic object that relates to the history and sociocultural paradigms of a given era. Moreover, through it, we can dwell on the deepest reflections on the human condition. It can also be used to propagate projects of domination, as Edward Said points out in his book Culture and Imperialism, connecting narrative, history and land conquest. Having said that, the aim of this paper is to analyse how Wole Soyinka elaborated his main theoretical work, Myth, Literature and African World, a collection of essays published in 1976, by comparing the philosophical, ideological and aesthetic practices of African, diasporic and European writers from the point of view of the Yoruba tradition, to which he belongs. Moreover, Soyinka believes that (literary) art has an important function in the formation of a people, in the construction of its political identity and in cultural regeneration, especially after the independence. The author's critical endeavour is that of attempting to construct a past. For him, the "African World" is not a mere allegory of the continent, and to understand it in this way would be to perpetuate a colonialist vision that would deny the subjectivities that cross black cultures, history and bodies. For him, comparative literature can be used not to "equate" local African texts with the European canon; but rather to recognise that they have aesthetic value and socio-cultural importance. Looking at the local, the particular and specific to each culture is, according to Soyinka, appropriate for dealing with African cultures, as opposed to abstractions of dialectical materialism or capitalist nationalism. In view of this, in his essays, the author creates a possibility for artistic and social reflection beyond the logic of Western politics.

Keywords: comparative literature, African Literature, Literary Theory, Yoruba Mythology, Wole Soyinka, Afrodiaspora

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5318 Relationship between Hepatokines and Insulin Resistance in Childhood Obesity

Authors: Mustafa Metin Donma, Orkide Donma

Abstract:

Childhood obesity is an important clinical problem because it may lead to chronic diseases during the adulthood period of the individual. Obesity is a metabolic disease associated with low-grade inflammation. The liver occurs at the center of metabolic pathways. Adropin, fibroblast growth factor-21 (FGF-21), and fetuin-A are hepatokines. Due to the immense participation of the liver in glucose metabolism, these liver-derived factors may be associated with insulin resistance (IR), which is a phenomenon discussed within the scope of obesity problems. The aim of this study is to determine the concentrations of adropin, FGF-21, and fetuin-A in childhood obesity, to point out possible differences between the obesity groups, and to investigate possible associations among these three hepatokines in obese and morbidly obese children. A total of one hundred and thirty-two children were included in the study. Two obese groups were constituted. The groups were matched in terms of mean ± SD values of ages. Body mass index values of obese and morbidly obese groups were 25.0 ± 3.5 kg/m² and 29.8 ± 5.7 kg/m², respectively. Anthropometric measurements including waist circumference, hip circumference, head circumference, and neck circumference were recorded. Informed consent forms were taken from the parents of the participants. The ethics committee of the institution approved the study protocol. Blood samples were obtained after overnight fasting. Routine biochemical tests, including glucose- and lipid-related parameters, were performed. Concentrations of the hepatokines (adropin, FGF-21, fetuin A) were determined by enzyme-linked immunosorbent assay. Insulin resistance indices such as homeostasis model assessment for IR (HOMA-IR), alanine transaminase-to aspartate transaminase ratio (ALT/AST), diagnostic obesity notation model assessment laboratory index, diagnostic obesity notation model assessment metabolic syndrome index as well as obesity indices such as diagnostic obesity notation model assessment-II index, and fat mass index were calculated using the previously derived formulas. Statistical evaluation of the study data as well as findings of the study was performed by SPSS for Windows. Statistical difference was accepted significant when p is smaller than 0.05. Statistically significant differences were found for insulin, triglyceride, high-density lipoprotein cholesterol levels of the groups. A significant increase was observed for FGF-21 concentrations in the morbidly obese group. Higher adropin and fetuin-A concentrations were observed in the same group in comparison with the values detected in the obese group (p > 0.05). There was no statistically significant difference between the ALT/AST values of the groups. In all of the remaining IR and obesity indices, significantly increased values were calculated for morbidly obese children. Significant correlations were detected between HOMA-IR and each of the hepatokines. The highest one was the association with fetuin-A (r=0.373, p=0.001). In conclusion, increased levels observed in adropin, FGF-21, and fetuin-A have shown that these hepatokines possess increasing potential going from obese to morbid obese state. Out of the correlations found with the IR index, the most affected hepatokine was fetuin-A, the parameter possibly used as the indicator of the advanced obesity stage.

Keywords: adropin, fetuin A, fibroblast growth factor-21, insulin resistance, pediatric obesity

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5317 Interaction of Metals with Non-Conventional Solvents

Authors: Evgeny E. Tereshatov, C. M. Folden

Abstract:

Ionic liquids and deep eutectic mixtures represent so-called non-conventional solvents. The former, composed of discrete ions, is a salt with a melting temperature below 100°С. The latter, consisting of hydrogen bond donors and acceptors, is a mixture of at least two compounds, resulting in a melting temperature depression in comparison with that of the individual moiety. These systems also can be water-immiscible, which makes them applicable for metal extraction. This work will cover interactions of In, Tl, Ir, and Rh in hydrochloric acid media with eutectic mixtures and Er, Ir, and At in a gas phase with chemically modified α-detectors. The purpose is to study chemical systems based on non-conventional solvents in terms of their interaction with metals. Once promising systems are found, the next step is to modify the surface of α-detectors used in the online element production at cyclotrons to get the detector chemical selectivity. Initially, the metal interactions are studied by means of the liquid-liquid extraction technique. Then appropriate molecules are chemisorbed on the surrogate surface first to understand the coating quality. Finally, a detector is covered with the same molecule, and the metal sorption on such detectors is studied in the online regime. It was found that chemical treatment of the surface can result in 99% coverage with a monolayer formation. This surface is chemically active and can adsorb metals from hydrochloric acid solutions. Similarly, a detector surface was modified and tested during cyclotron-based experiments. Thus, a procedure of detectors functionalization has been developed, and this opens an interesting opportunity of studying chemisorption of elements which do not have stable isotopes.

Keywords: mechanism, radioisotopes, solvent extraction, gas phase sorption

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5316 Bifunctional Electrospun Fibers Based on Poly(Lactic Acid)/Calcium Oxide Nanocomposites as a Potential Scaffold for Bone Tissue Engineering

Authors: Daniel Canales, Fabián Alvarez, Pablo Varela, Marcela Saavedra, Claudio García, Paula Zapata

Abstract:

Calcium oxide nanoparticles (n-CaO) ca. 8 nm were obtained from eggshell waste. The n-CaO was incorporated into Poly(lactic acid) PLA matrix in 10 and 20 wt.% of filler content by electrospinning process to obtain PLA/n-CaO nanocomposite fibers as a potential use in scaffold for bone tissue regeneration. The fibers morphology and diameter were homogeneity, the PLA had a diameter of 2.2 ± 0.8 µm and, with the nanoparticles incorporation (20wt.%), reached ca. 2.9 ± 0.9 µm. The PLA/n-CaO nanocomposites fibers showed in vitro bioactivity, capable of inducing the precipitation of hydroxyapatite (HA) layer in the fiber surface after 7 days in Simulated Body Solution (SBF). The biocidal and biological properties of PLA/n-Cao with 20 wt.% were evaluated, showing a 30% reduction in bacterial viability against S. aureus and 11% for E. coli after 6 hours of bacterial suspensions exposure. Furthermore, the fibers did not show a cytotoxic effect on the bone marrow ST-2 cell line, permitting the cell adhesion and proliferation in Roswell Park Memorial Institute medium (RPMI). The PLA/n-CaO with 20 wt.% of nanoparticles showed a higher capacity to promote the osteogenic differentiation, significantly increasing the alkaline phosphatase (ALP) expression after 7 days compared to PLA and cell control. The in vivo analysis corroborated the biocompatibility of scaffolds prepared, the presence of n-CaO in PLA reduced the formation of fibrous encapsulation of the material improve the healing process.

Keywords: electrospun scaffolds, PLA based nanocomposites, calcium oxide nanoparticles, bioactive materials, tissue engineering

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5315 Comparison between Simulation and Experimentally Observed Interactions between Two Different Sized Magnetic Beads in a Fluidic System

Authors: Olayinka Oduwole, Steve Sheard

Abstract:

The magnetic separation of biological cells using super-magnetic beads has been used widely for various bioassays. These bioassays can further be integrated with other laboratory components to form a biosensor which can be used for cell sorting, mixing, purification, transport, manipulation etc. These bio-sensing applications have also been facilitated by the wide availability of magnetic beads which range in size and magnetic properties produced by different manufacturers. In order to improve the efficiency and separation capabilities of these biosensors, it is important to determine the magnetic force induced velocities and interaction of beads within the magnetic field; this will help biosensor users choose the desired magnetic bead for their specific application. This study presents for the first time the interaction between a pair of different sized super-paramagnetic beads suspended in a static fluid moving within a uniform magnetic field using a modified finite-time-finite-difference scheme. A captured video was used to record the trajectory pattern and a good agreement was obtained between the simulated trajectories and the video data. The model is, therefore, a good approximation for predicting the velocities as well as the interaction between various magnetic particles which differ in size and magnetic properties for bio-sensing applications requiring a low concentration of magnetic beads.

Keywords: biosensor, magnetic field, magnetic separation, super-paramagnetic bead

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5314 Electrochemical Determination of Caffeine Content in Ethiopian Coffee Samples Using Lignin Modified Glassy Carbon Electrode

Authors: Meareg Amare, Senait Aklog

Abstract:

Lignin film was deposited at the surface of the glassy carbon electrode potential-statically. In contrast to the unmodified glassy carbon electrode, an oxidative peak with an improved current and overpotential for caffeine at the modified electrode showed catalytic activity of the modifier towards oxidation of caffeine. Linear dependence of peak current on caffeine concentration in the range 6 × 10⁻⁶ to 100 × 10⁻⁶ mol L⁻¹ with determination coefficient and method detection limit (LoD = 3 s/slope) of 0.99925 and 8.37 × 10⁻⁷ mol L⁻¹, respectively, supplemented by recovery results of 93.79–102.17%, validated the developed method. An attempt was made to determine the caffeine content of aqueous coffee extracts of Ethiopian coffees grown in four coffee cultivating localities (Wonbera, Wolega, Finoteselam, and Zegie) and hence to evaluate the correlation between users preference and caffeine content. In agreement with reported works, caffeine contents (w/w%) of 0.164 in Wonbera coffee; 0.134 in Wolega coffee; 0.097 in Finoteselam coffee; and 0.089 in Zegie coffee were detected, confirming the applicability of the developed method for determination of caffeine in a complex matrix environment. The result indicated that users’ highest preference for Wonbera and least preference for Zegie cultivated coffees are in agreement with the caffeine content.

Keywords: electrochemical, lignin, caffeine, electrode

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5313 Feasibility Study of Implementing Electronic Commerce in Food Industries with a Case Study

Authors: Maryam Safarirad

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Fast and increasing growth of electronic commerce (e-commerce) in developed countries and its resulting competitive advantages mean that those countries should revise dramatically their trade and commercial strategies and policies. Regarding the importance of food industry in Iran, the current paper studies the feasibility of implementing the e-commerce system in Shiraz’s petrochemical unit. The statistical population of the study includes 29 senior managers and experts of the food industries. In the present Feasibility study of implementing electronic commerce 249 research, senior managers and experts’ opinions on feasibility have been examined and some feedbacks have resulted in from the opinions. The current research concludes that the organization under study does not have favorable state either in software or in hardware. Implementation of the e-commerce system in food industries would reduce the average value of the transaction costs.

Keywords: electronic trading, electronic commerce, electronic exchange of information, feasibility study, information technology, virtual shopping, computer networks, electronic commerce laws, food industry

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5312 Role of Hyperbaric Oxygen Therapy in Management of Diabetic Foot

Authors: Magdy Al Shourbagi

Abstract:

Diabetes mellitus is the commonest cause of neuropathy. The common pattern is a distal symmetrical sensory polyneuropathy, associated with autonomic disturbances. Less often, Diabetes mellitus is responsible for a focal or multifocal neuropathy. Common causes for non-healing of diabetic foot are the infection and ischemia. Diabetes mellitus is associated with a defective cellular and humoral immunity. Particularly, decreased phagocytosis, decreased chemotaxis, impaired bacterial killing and abnormal lymphocytic function resulting in a reduced inflammatory reaction and defective wound healing. Hyperbaric oxygen therapy is defined by the Undersea and Hyperbaric Medical Society as a treatment in which a patient intermittently breathes 100% oxygen and the treatment chamber is pressurized to a pressure greater than sea level (1 atmosphere absolute). The pressure increase may be applied in mono-place (single person) or multi-place chambers. Multi-place chambers are pressurized with air, with oxygen given via face mask or endotracheal tube; while mono-place chambers are pressurized with oxygen. Oxygen gas plays an important role in the physiology of wound healing. Hyperbaric oxygen therapy can raise tissue oxygen tensions to levels where wound healing can be expected. HBOT increases the killing ability of leucocytes also it is lethal for certain anaerobic bacteria and inhibits toxin formation in many other anaerobes. Multiple anecdotal reports and studies in HBO therapy in diabetic patients report that HBO can be an effective adjunct therapy in the management of diabetic foot wounds and is associated with better functional outcomes.

Keywords: hyperbari oxygen therapy, diabetic foot, neuropathy, multiplace chambers

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5311 Real-Time Classification of Hemodynamic Response by Functional Near-Infrared Spectroscopy Using an Adaptive Estimation of General Linear Model Coefficients

Authors: Sahar Jahani, Meryem Ayse Yucel, David Boas, Seyed Kamaledin Setarehdan

Abstract:

Near-infrared spectroscopy allows monitoring of oxy- and deoxy-hemoglobin concentration changes associated with hemodynamic response function (HRF). HRF is usually affected by natural physiological hemodynamic (systemic interferences) which occur in all body tissues including brain tissue. This makes HRF extraction a very challenging task. In this study, we used Kalman filter based on a general linear model (GLM) of brain activity to define the proportion of systemic interference in the brain hemodynamic. The performance of the proposed algorithm is evaluated in terms of the peak to peak error (Ep), mean square error (MSE), and Pearson’s correlation coefficient (R2) criteria between the estimated and the simulated hemodynamic responses. This technique also has the ability of real time estimation of single trial functional activations as it was applied to classify finger tapping versus resting state. The average real-time classification accuracy of 74% over 11 subjects demonstrates the feasibility of developing an effective functional near infrared spectroscopy for brain computer interface purposes (fNIRS-BCI).

Keywords: hemodynamic response function, functional near-infrared spectroscopy, adaptive filter, Kalman filter

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5310 New Challenge: Reduction of Aflatoxin M1 Residues in Cow’s Milk by MilBond Dietary Hydrated Sodium Calcium Aluminosilicate (HSCAS) and Its Effect on Milk Composition

Authors: A. Aly Salwa, H. Diekmann, S. Hafiz Ragaa, DG Abo Elhassan

Abstract:

This study was aimed to evaluate the effect of Milbond (HSCAS) on aflatoxin M1 in artificially contaminated cows milk. Chemisorption compounds used in this experiment were MIlBond, hydrated sodium calcium aluminosilicate (HSCAS). Raw cow milk were artificially exposed to aflatoxin M1 in a concentration of 100 ppb) with addition of Nilbond at 0.5, 1, 2 and 3 % at room temperature for 30 minutes. Aflatoxin M1 was decreased more than 95% by HSCAS at 2%. Milk composition consist of protein, fat, lactose, solid non fat and total solid were affected by addition of some adsorbents were not significantly affected (p 0.05). Tthis method did not involve degrading the toxin, milk may be free from toxin degradation products and is safe for consumption. In addition, the added material may be easily separated from milk after the substance adsorbs the toxin. Thus, this method should be developed by further researches for determining effects of these compounds on functional properties of milk. The ability of hydrated sodium calcium aluminosilicate to prevent or reduce the level of aflatoxin MI residues in milk is critically needed. This finding has important implications, because milk is ultimately consumed by humans and animals, and the reduction of aflatoxin contamination in the milk could have an important impact on their health.

Keywords: aflatoxin M1, Hydrated sodium calcium aluminium silicate, detoxification, raw cow milk

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5309 Purification, Biochemical Characterization and Application of an Extracellular Alkaline Keratinase Produced by Aspergillus sp. DHE7

Authors: Dina Helmy El-Ghonemy, Thanaa Hamed Ali

Abstract:

The aim of this study was to purify and characterize a keratinolytic enzyme produced by Aspergillus sp. DHE7 cultured in basal medium containing chicken feather as substrate. The enzyme was purified through ammonium sulfate saturation of 60%, followed by gel filtration chromatography in Sephadex G-100, with a 16.4-purification fold and recovery yield of 52.2%. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis revealed that the purified enzyme is a monomeric enzyme with an apparent molecular mass of 30 kDa — the purified keratinase of Aspergillus sp. DHE7 exhibited activity in a broad range of pH (7- 9) and temperature (40℃-60℃) profiles with an optimal activity at pH eight and 50℃. The keratinolytic activity was inhibited by protease inhibitors such as phenylmethylsulfonyl fluoride and ethylenediaminetetraacetate, while no reduction of activity was detected by the addition of dimethyl sulfoxide (DMSO). Bivalent cations, Ca²⁺ and Mn²⁺, were able to greatly enhance the activity of keratinase by 125.7% and 194.8%, respectively, when used at one mM final concentration. On the other hand, Cu²⁺ and Hg²⁺ inhibited the enzyme activity, which might be indicative of essential vicinal sulfhydryl groups of the enzyme for productive catalysis. Furthermore, the purified keratinase showed significant stability and compatibility against the tested commercial detergents at 37ºC. Therefore, these results suggested that the purified keratinase from Aspergillus sp. DHE7 may have potential use in the detergent industry and should be of interest in the processing of poultry feather waste.

Keywords: Aspergillus sp. DHE7, biochemical characterization, keratinase, purification, waste management

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5308 Analysis of Dust Particles in Snow Cover in the Surroundings of the City of Ostrava: Particle Size Distribution, Zeta Potential and Heavy Metal Content

Authors: Roman Marsalek

Abstract:

In this paper, snow samples containing dust particles from several sampling points around the city of Ostrava were analyzed. The pH values of sampled snow were measured and solid particles analyzed. Particle size, zeta potential and content of selected heavy metals were determined in solid particles. The pH values of most samples lay in the slightly acid region. Mean values of particle size ranged from 290.5 to 620.5 nm. Zeta potential values varied between -5 and -26.5 mV. The following heavy metal concentration ranges were found: copper 0.08-0.75 mg/g, lead 0.05-0.9 mg/g, manganese 0.45-5.9 mg/g and iron 25.7-280.46 mg/g. The highest values of copper and lead were found in the vicinity of busy crossroads, and on the contrary, the highest levels of manganese and iron were detected close to a large steelworks. The proportion between pH values, zeta potentials, particle sizes and heavy metal contents was established. Zeta potential decreased with rising pH values and, simultaneously, heavy metal content in solid particles increased. At the same time, higher metal content corresponded to lower particle size.

Keywords: dust, snow, zeta potential, particles size distribution, heavy metals

Procedia PDF Downloads 353
5307 CFD Analysis of Multi-Phase Reacting Transport Phenomena in Discharge Process of Non-Aqueous Lithium-Air Battery

Authors: Jinliang Yuan, Jong-Sung Yu, Bengt Sundén

Abstract:

A computational fluid dynamics (CFD) model is developed for rechargeable non-aqueous electrolyte lithium-air batteries with a partial opening for oxygen supply to the cathode. Multi-phase transport phenomena occurred in the battery are considered, including dissolved lithium ions and oxygen gas in the liquid electrolyte, solid-phase electron transfer in the porous functional materials and liquid-phase charge transport in the electrolyte. These transport processes are coupled with the electrochemical reactions at the active surfaces, and effects of discharge reaction-generated solid Li2O2 on the transport properties and the electrochemical reaction rate are evaluated and implemented in the model. The predicted results are discussed and analyzed in terms of the spatial and transient distribution of various parameters, such as local oxygen concentration, reaction rate, variable solid Li2O2 volume fraction and porosity, as well as the effective diffusion coefficients. It is found that the effect of the solid Li2O2 product deposited at the solid active surfaces is significant on the transport phenomena and the overall battery performance.

Keywords: Computational Fluid Dynamics (CFD), modeling, multi-phase, transport phenomena, lithium-air battery

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5306 Antioxidant and Anticancer Activities of Ethanolic Extract from Monascus purpureus

Authors: M. Pourshirazi, M. Esmaelifar, A. Aliahmadi, F. Yazdian, A. S. Hatamian Zarami, S. J. Ashrafi

Abstract:

Medicinal fungi are the new potential source of drugs to improve the treatment of diseases with association to oxidative agents such as cancers. Monascus purpureus contains functional components potentially effective in improving human health. In the present work, ethanolic extract of Monascus purpureus (EEM) was evaluated for health improving potential mainly focusing on antioxidant and anticancer activities. Ferric ion reducing power (FRAP), scavenging of DPPH radicals and determining viability of breast carcinoma MCF-7 and cervical carcinoma HeLa cells with MTT assay were evaluated. Our data showed a significant antioxidant activity of EEM with 142.45 µg/ml inhibition concentration of 50% DPPH radicals and 2112.33 µg eq.Fe2+/mg extract of FRAP assay. These results might be caused by antioxidant components such as pigments and phenolic compounds. Further, the results demonstrated that EEM caused significant reduction in the viability of MCF-7 with IC50 of 7 µg/ml but not have good effect against viability of HeLa cells. Accordingly, Monascus purpureus is presented as a strong potential of breast cancer treatment. In further study, the mechanistic studies are needed to determine the mechanisms of anticancer activity of EEM.

Keywords: Monascus purpureus, antioxidant, cancer, ethanolic extract

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5305 Investigations on the Cytotoxicity and Antimicrobial Activities of Terezine E and 14-Hydroxyterezine D

Authors: Mariam Mojally, Randa Abdou, Wisal Bokhari, Sultan Sab, Mohammed Dawoud, Amjad Albohy

Abstract:

Secondary metabolites produced by endophytes are an excellent source of biologically active compounds. In our current study, we evaluated terezine E and 14-hydroxyterezine D for binding to the active site of histone deacetylase (PDB ID: 4CBT) and matrix metalloproteinase 9 (PDB ID: 4H3X) by molecular docking using AutoDock Vina software after having tested their cytotoxic activities on three cell lines (human ductal breast epithelial tumor cells (T47D)-HCC1937), human hepatocarcinoma cell line (HepG2)-HB8065), and human colorectal carcinoma cells (HCT-116)-TCP1006, purchased from ATCC, USA)). Additionally, their antimicrobial activities were investigated, and their minimum inhibitory concentration (MIC) values were determined against P. notatum and S. aureus by the broth microdilution method. Higher cytotoxicity was observed for terezine E against all tested cell lines compared to 14-hydroxyterezine D. Molecular docking results supported the high cytotoxicity of terezine E and showed higher binding affinity with 4CBT with an energy score of 9 kcal/mol. Terezine E showed higher antibacterial and antifungal activities than 14-hydroxyrerezine D: MIC values were 15.45 and 21.73 mg/mL against S. aureus and 8.61 and 11.54 mg/mL against P. notatum, respectively

Keywords: Terezine E, 14-Hydroxyterezine D, cytotoxicity, antimicrobial activity, molecular docking

Procedia PDF Downloads 53
5304 Establishments of an Efficient Platform for Genome Editing in Grapevine

Authors: S. Najafi, E. Bertini, M. Pezzotti, G.B. Tornielli, S. Zenoni

Abstract:

Grapevine is an important agricultural fruit crop plant consumed worldwide and with a key role in the global economy. Grapevine is strongly affected by both biotic and abiotic stresses, which impact grape growth at different stages, such as during plant and berry development and pre- and post-harvest, consequently causing significant economic losses. Recently global warming has propelled the anticipation of the onset of berry ripening, determining the reduction of a grape color and increased volatilization of aroma compounds. Climate change could negatively alter the physiological characteristics of the grape and affect the berry and wine quality. Modern plant breeding can provide tools such as genome editing for improving grape resilience traits while maintaining intact the viticultural and oenological quality characteristics of the genotype. This study aims at developing a platform for genome editing application in grapevine plants with the final goal to improve berry quality, biotic, and abiotic resilience traits. We chose to directly deliver ribonucleoproteins (RNP, preassembled Cas protein and guide RNA) into plant protoplasts, and, from these cell structures, regenerate grapevine plants edited in specific selected genes controlling traits of interest. Edited plants regenerated by somatic embryogenesis from protoplasts will then be sequenced and molecularly characterized. Embryogenic calli of Sultana and Shiraz cultivars were initiated from unopened leaves of in-vitro shoot tip cultures and from stamens, respectively. Leaves were placed on NB2 medium while stamens on callus initiation medium (PIV) medium and incubated in the dark at 28 °C for three months. Viable protoplasts, tested by FDA staining, isolated from embryogenic calli were cultured by disc method at 1*105 protoplasts/ml. Mature well-shaped somatic embryos developed directly in the protoplast culture medium two months later and were transferred in the light into to shooting medium for further growth. Regenerated plants were then transferred to the greenhouse; no phenotypic alterations were observed when compared to non in-vitro cultured plants. The performed experiments allowed to established an efficient protocol of embryogenic calli production, protoplast isolation, and regeneration of the whole plant through somatic embryogenesis in both Sultana and Shiraz. Regenerated plants, through direct somatic embryogenesis deriving from a single cell, avoid the risk of chimerism during the regeneration process, therefore improving the genome editing process. As pre-requisite of genome editing, an efficient method for transfection of protoplast by yellow fluorescent protein (YFP) marker genes was also established and experiments of direct delivery of CRISPR–Cas9 ribonucleoproteins (RNPs) in protoplasts to achieve efficient DNA-free targeted mutations are in progress.

Keywords: CRISPR-cas9, plant regeneration, protoplast isolation, Vitis vinifera

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5303 Electrochemical Performance of Carbon Nanotube Based Supercapacitor

Authors: Jafar Khan Kasi, Ajab Khan Kasi, Muzamil Bokhari

Abstract:

Carbon nanotube is one of the most attractive materials for the potential applications of nanotechnology due to its excellent mechanical, thermal, electrical and optical properties. In this paper we report a supercapacitor made of nickel foil electrodes, coated with multiwall carbon nanotubes (MWCNTs) thin film using electrophoretic deposition (EPD) method. Chemical vapor deposition method was used for the growth of MWCNTs and ethanol was used as a hydrocarbon source. High graphitic multiwall carbon nanotube was found at 750 C analyzing by Raman spectroscopy. We observed the electrochemical performance of supercapacitor by cyclic voltammetry. The electrodes of supercapacitor fabricated from MWCNTs exhibit considerably small equivalent series resistance (ESR), and a high specific power density. Electrophoretic deposition is an easy method in fabricating MWCNT electrodes for high performance supercapacitor.

Keywords: carbon nanotube, chemical vapor deposition, catalyst, charge, cyclic voltammetry

Procedia PDF Downloads 543
5302 Insecticide Efficacy against Jassids in Egg Plants

Authors: Zunnu Raen Akhtar, Farhan Ali, Muhammad Saeed-Ur-Rehman

Abstract:

Jassids are considered as serious sucking pests in eggplants. Jassids can be controlled using imidacloprid, but it can also result in non-target ecological impacts on eco-system. It can also result in reduced population of predators of jassids in the field. An experiment was conducted on jassids, Amrasca sp. reared on eggplant leaves were treated with insecticide imidacloprid at lower, recommended and higher doses including 1L, 2L, 3L respectively. 3rd instar larvae and adults of jassids were exposed to lower, recommended, higher doses. Mortality tests were repeated three times for each dose and insect growth stage. Imidacloprid was sprayed on the leaves followed by drying. Data was recorded for 4, 8, 12, 16, 20, 24 hours after spraying insecticide on the leaves. Results showed that higher mortality was observed in higher and recommended doses, while slow mortality was observed in the case of lower dose. It can be asserted that higher and recommended doses causing immediate mortality of insects are better to control Amrasca sp. in the field, it will not cause immediate resistance development in insects against imidacloprid.

Keywords: Amrasca sp., imidacloprid, egg plant, efficacy

Procedia PDF Downloads 211
5301 The Effect of Potassium Hydroxide on Fine Soil Treated with Olivine

Authors: Abdelmaoula Mahamoud Tahir, Sedat Sert

Abstract:

The possibility of improving the shear strength of unsaturated clayey soil with the addition of olivine was investigated in this paper. Unconsolidated undrained triaxial tests (UU), under different cell pressures (namely: 100 kPa and 200 kPa), with varying percentages of olivine (10% and 20% by weight) and with one day, 28 days, and 56 days curing times, were performed to determine the shear strength of the soil. The increase in strength was observed as a function of the increase in olivine content. An olivine content of 25% was determined as the optimum value to achieve the targeted improvement for both cure times. A comparative study was also conducted between clay samples treated with only olivine and others in the presence of potassium hydroxide (KOH). Clay samples treated with olivine and activated with potassium hydroxide (KOH) had higher shear strength than non-activated olivine-treated samples. It was determined that the strength of the clay samples treated with only olivine did not increase over time and added resistance only with the high specific gravity of olivine. On the other hand, the samples activated with potassium hydroxide (KOH) added to the resistance with high specific gravity and the chemical bonds of olivine. Morphological and mineralogical analyzes were carried out in this study to see and analyze the chemical bonds formed after the reaction. The main components of this improvement were the formation of magnesium-aluminate-hydrate and magnesium-silicate-hydrate. Compared to older methods such as cement addition, these results show that in stabilizing clayey soils, olivine additive offers an energy-efficient alternative for reducing carbon dioxide emissions.

Keywords: ground stabilization, clay, olivine additive, KOH, microstructure

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5300 Residual Stress Around Embedded Particles in Bulk YBa2Cu3Oy Samples

Authors: Anjela Koblischka-Veneva, Michael R. Koblischka

Abstract:

To increase the flux pinning performance of bulk YBa2Cu3O7-δ (YBCO or Y-123) superconductors, it is common to employ secondary phase particles, either Y2BaCuO5 (Y-211) particles created during the growth of the samples or additionally added (nano)particles of various types, embedded in the superconducting Y-123 matrix. As the crystallographic parameters of all the particles indicate a misfit to Y-123, there will be residual strain within the Y-123 matrix around such particles. With a dedicated analysis of electron backscatter diffraction (EBSD) data obtained on various bulk, Y-123 superconductor samples, the strain distribution around such embedded secondary phase particles can be revealed. The results obtained are presented in form of Kernel Average Misorientation (KAM) mappings. Around large Y-211 particles, the strain can be so large that YBCO subgrains are formed. Therefore, it is essential to properly control the particle size as well as their distribution within the bulk sample to obtain the best performance. The impact of the strain distribution on the flux pinning properties is discussed.

Keywords: Bulk superconductors, EBSD, Strain, YBa2Cu3Oy

Procedia PDF Downloads 139
5299 Introduction of a Medicinal Plants Garden to Revitalize a Botany Curriculum for Non-Science Majors

Authors: Rosa M. Gambier, Jennifer L. Carlson

Abstract:

In order to revitalize the science curriculum for botany courses for non-science majors, we have introduced the use of the medicinal plants into a first-year botany course. We have connected the use of scientific method, scientific inquiry and active learning in the classroom with the study of Western Traditional Medical Botany. The students have researched models of Botanical medicine and have designed a sustainable medicinal plants garden using native medicinal plants from the northeast. Through the semester, the students have researched their chosen species, planted seeds in the college greenhouse, collected germination ratios, growth ratios and have successfully produced a beginners medicinal plant garden. Phase II of the project will be to tie in SCCCs community outreach goals by involving the public in the expanded development of the garden as a way of sharing learning about medicinal plants and traditional medicine outside the classroom.

Keywords: medicinal plant garden, botany curriculum, active learning, community outreach

Procedia PDF Downloads 289