Search results for: glass structure and properties
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 15403

Search results for: glass structure and properties

4693 Mining the Proteome of Fusobacterium nucleatum for Potential Therapeutics Discovery

Authors: Abdul Musaweer Habib, Habibul Hasan Mazumder, Saiful Islam, Sohel Sikder, Omar Faruk Sikder

Abstract:

The plethora of genome sequence information of bacteria in recent times has ushered in many novel strategies for antibacterial drug discovery and facilitated medical science to take up the challenge of the increasing resistance of pathogenic bacteria to current antibiotics. In this study, we adopted subtractive genomics approach to analyze the whole genome sequence of the Fusobacterium nucleatum, a human oral pathogen having association with colorectal cancer. Our study divulged 1499 proteins of Fusobacterium nucleatum, which has no homolog in human genome. These proteins were subjected to screening further by using the Database of Essential Genes (DEG) that resulted in the identification of 32 vitally important proteins for the bacterium. Subsequent analysis of the identified pivotal proteins, using the KEGG Automated Annotation Server (KAAS) resulted in sorting 3 key enzymes of F. nucleatum that may be good candidates as potential drug targets, since they are unique for the bacterium and absent in humans. In addition, we have demonstrated the 3-D structure of these three proteins. Finally, determination of ligand binding sites of the key proteins as well as screening for functional inhibitors that best fitted with the ligands sites were conducted to discover effective novel therapeutic compounds against Fusobacterium nucleatum.

Keywords: colorectal cancer, drug target, Fusobacterium nucleatum, homology modeling, ligands

Procedia PDF Downloads 388
4692 Faster, Lighter, More Accurate: A Deep Learning Ensemble for Content Moderation

Authors: Arian Hosseini, Mahmudul Hasan

Abstract:

To address the increasing need for efficient and accurate content moderation, we propose an efficient and lightweight deep classification ensemble structure. Our approach is based on a combination of simple visual features, designed for high-accuracy classification of violent content with low false positives. Our ensemble architecture utilizes a set of lightweight models with narrowed-down color features, and we apply it to both images and videos. We evaluated our approach using a large dataset of explosion and blast contents and compared its performance to popular deep learning models such as ResNet-50. Our evaluation results demonstrate significant improvements in prediction accuracy, while benefiting from 7.64x faster inference and lower computation cost. While our approach is tailored to explosion detection, it can be applied to other similar content moderation and violence detection use cases as well. Based on our experiments, we propose a "think small, think many" philosophy in classification scenarios. We argue that transforming a single, large, monolithic deep model into a verification-based step model ensemble of multiple small, simple, and lightweight models with narrowed-down visual features can possibly lead to predictions with higher accuracy.

Keywords: deep classification, content moderation, ensemble learning, explosion detection, video processing

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4691 Improvement of Analysis Vertical Oil Exploration Wells (Case Study)

Authors: Azza Hashim Abbas, Wan Rosli Wan Suliman

Abstract:

The old school of study, well testing reservoir engineers used the transient pressure analyses to get certain parameters and variable factors on the reservoir's physical properties, such as, (permeability-thickness). Recently, the difficulties facing the newly discovered areas are the convincing fact that the exploration and production (E&p) team should have sufficiently accurate and appropriate data to work with due to different sources of errors. The well-test analyst does the work without going through well-informed and reliable data from colleagues which may consequently cause immense environmental damage and unnecessary financial losses as well as opportunity losses to the project. In 2003, new potential oil field (Moga) face circulation problem well-22 was safely completed. However the high mud density had caused an extensive damage to the nearer well area which also distracted the hypothetical oil rate of flow that was not representive of the real reservoir characteristics This paper presents methods to analyze and interpret the production rate and pressure data of an oil field. Specifically for Well- 22 using the Deconvolution technique to enhance the transient pressure .Applying deconvolution to get the best range of certainty of results needed for the next subsequent operation. The range determined and analysis of skin factor range was reasonable.

Keywords: well testing, exploration, deconvolution, skin factor, un certainity

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4690 Dielectric Spectroscopy Investigation of Hydrophobic Silica Aerogel

Authors: Deniz Bozoglu, Deniz Deger, Kemal Ulutas, Sahin Yakut

Abstract:

In recent years, silica aerogels have attracted great attention due to their outstanding properties, and their wide variety of potential applications such as microelectronics, nuclear and high-energy physics, optics and acoustics, superconductivity, space-physics. Hydrophobic silica aerogels were successfully synthesized in one-step by surface modification at ambient pressure. FT-IR result confirmed that Si-OH groups were successfully converted into hydrophobic and non-polar Si-CH3 groups by surface modification using trimethylchloro silane (TMCS) as co-precursor. Using Alpha-A High-Resolution Dielectric, Conductivity and Impedance Analyzer, AC conductivity of samples were examined at temperature range 293-423 K and measured over frequency range between 1-106 Hz. The characteristic relaxation time decreases with increasing temperature. The AC conductivity follows σ_AC (ω)=σ_t-σ_DC=Aω^s relation at frequencies higher than 10 Hz, and the dominant conduction mechanism is found to obey the Correlated Barrier Hopping (CBH) mechanism. At frequencies lower than 10 Hz, the electrical conduction is found to be in accordance with DC conduction mechanism. The activation energies obtained from AC conductivity results and it was observed two relaxation regions.

Keywords: aerogel, synthesis, dielectric constant, dielectric loss, relaxation time

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4689 Detection of Cytotoxicity of Green Synthesized Silver, Gold, and Silver/Gold Bimetallic on Baby Hamster Kidney-21 Cells Using MTT Assay

Authors: Naila Sher, Mushtaq Ahmed, Nadia Mushtaq, Rahmat Ali Khan

Abstract:

In cancer therapy, nanoparticles (NPs) shall be applied possibly by inoculation in the veins of humans. This action will connect them with white (WBCs) and red blood cells (RBCs) in the bloodstream before they reach their main targeted cancer cells. However, possible effects of silver, gold, and silver/gold bimetallic NPs (Ag, Au, and Ag/Au BNPs) on baby hamster kidney-21 (BHK-21) cells were studied by MTT assay. Here, Ag, Au, and their Ag/Au BNPs (bimetallic nanoparticles) were synthesized by using Hippeastrum hybridum (HH) extract. These NPs were characterized by UV-visible spectroscopy, FT-IR, XRD, and EDX, and SEM analysis. XRD analysis conferring the crystal structure with an average size of 13.3, 10.72, and 8.34nm of Ag, Au, and Ag/Au BNPs, respectively. SEM showed that Ag, Au, and Ag/Au BNPs had irregular morphologies, with nano measures calculated sizes of 40, 30, and 20 nm respectively. EDX spectrometers confirmed the presence of elemental Ag signal of the AgNPs with 22.75%, Au signal of the AuNPs with 48.08%, Ag signal with 12%, and Au signal with 38.26% of the Ag/Au BNPs. The BHK-21cells were incubated in the existence of doxorubicin, plant extract, Ag, Au, and Ag/Au BNPs. The cytotoxic effects could be observed in a dose-dependent mode; doxorubicin and Ag/Au BNPs were more toxic than plant extract, Ag, and Au NPs. It is demonstrated that NPs interact with BHK-21cells and significantly reduce cell viability in a concentration-dependent manner. However, to reduce the potential threats of NPs further studies are recommended.

Keywords: hippeastrum hybridum, nanoparticle, BHK-21cells

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4688 Influence of Thermal Treatments on Ovomucoid as Allergenic Protein

Authors: Nasser A. Al-Shabib

Abstract:

Food allergens are most common non-native form when exposed to the immune system. Most food proteins undergo various treatments (e.g. thermal or proteolytic processing) during food manufacturing. Such treatments have the potential to impact the chemical structure of food allergens so as to convert them to more denatured or unfolded forms. The conformational changes in the proteins may affect the allergenicity of treated-allergens. However, most allergenic proteins possess high resistance against thermal modification or digestive enzymes. In the present study, ovomucoid (a major allergenic protein of egg white) was heated in phosphate-buffered saline (pH 7.4) at different temperatures, aqueous solutions and on different surfaces for various times. The results indicated that different antibody-based methods had different sensitivities in detecting the heated ovomucoid. When using one particular immunoassay‚ the immunoreactivity of ovomucoid increased rapidly after heating in water whereas immunoreactivity declined after heating in alkaline buffer (pH 10). Ovomucoid appeared more immunoreactive when dissolved in PBS (pH 7.4) and heated on a stainless steel surface. To the best of our knowledge‚ this is the first time that antibody-based methods have been applied for the detection of ovomucoid adsorbed onto different surfaces under various conditions. The results obtained suggest that use of antibodies to detect ovomucoid after food processing may be problematic. False assurance will be given with the use of inappropriate‚ non-validated immunoassays such as those available commercially as ‘Swab’ tests. A greater understanding of antibody-protein interaction after processing of a protein is required.

Keywords: ovomucoid, thermal treatment, solutions, surfaces

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4687 Numerical Investigation of Static and Dynamic Responses of Fiber Reinforced Sand

Authors: Sandeep Kumar, Mahesh Kumar Jat, Rajib Sarkar

Abstract:

Soil reinforced with randomly distributed fibers is an attractive means to improve the performance of soil in a cost effective manner. Static and dynamic characterization of fiber reinforced soil have become important to evaluate adequate performance for all classes of geotechnical engineering problems. Present study investigates the behaviour of fiber reinforced cohesionless soil through numerical simulation of triaxial specimen. The numerical model has been validated with the existing literature of laboratory triaxial compression testing. A parametric study has been done to find out optimum fiber content for shear resistance. Cyclic triaxial testing has been simulated and the stress-strain response of fiber-reinforced sand has been examined considering different combination of fiber contents. Shear modulus values and damping values of fiber-reinforced sand are evaluated. It has been observed from results that for 1.0 percent fiber content shear modulus increased 2.28 times and damping ratio decreased 4.6 times. The influence of amplitude of cyclic strain, confining pressure and frequency of loading on the dynamic properties of fiber reinforced sand has been investigated and presented.

Keywords: damping, fiber reinforced soil, numerical modelling, shear modulus

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4686 A Structural and Magnetic Investigation of the Inversion Degree in Spinel NiFe2O4, ZnFe2O4 and Ni0.5Zn0.5Fe2O4 Ferrites Prepared by Soft Mechanochemical Synthesis

Authors: Z. Ž. Lazarević, D. L. Sekulić, V. N. Ivanovski, N. Ž. Romčević

Abstract:

NiFe2O4 (nickel ferrite), ZnFe2O4 (zinc ferrite) and Ni0.5Zn0.5Fe2O4 (nickel-zinc ferrite) were prepared by mechanochemical route in a planetary ball mill starting from mixture of the appropriate quantities of the Ni(OH)2/Fe(OH)3, Zn(OH)2/Fe(OH)3 and Ni(OH)2/Zn(OH)2/Fe(OH)3 hydroxide powders. In order to monitor the progress of chemical reaction and confirm phase formation, powder samples obtained after 25 h, 18 h and 10 h of milling were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), IR, Raman and Mössbauer spectroscopy. It is shown that the soft mechanochemical method, i.e. mechanochemical activation of hydroxides, produces high quality single phase ferrite samples in much more efficient way. From the IR spectroscopy of single phase samples it is obvious that energy of modes depends on the ratio of cations. It is obvious that all samples have more than 5 Raman active modes predicted by group theory in the normal spinel structure. Deconvolution of measured spectra allows one to conclude that all complex bands in the spectra are made of individual peaks with the intensities that vary from spectrum to spectrum. The deconvolution of Raman spectra allows to separate contributions of different cations to a particular type of vibration and to estimate the degree of inversion.

Keywords: ferrites, Raman spectroscopy, IR spectroscopy, Mössbauer measurements

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4685 Synthesis of Biofuels of New Generation

Authors: Selena Gutiérrez, Araceli Martínez

Abstract:

One of the most important challenges worldwide, scientific and technological, is to have a sustainable energy source; friendly to the environment and widely available. Currently, the 85% of the energy used comes from the fossil sources. Another important environmental problem is that several rubber products (tires, gloves, hoses, among others) are discarded practically without any treatment. In nature, the degradation of such products will take at least 500 years. In 2009, the worldwide rubber production was about 23.6 million tons. In order to solve this problems, our research focus in an alternative synthesis of biofuels in a two-step approach: The metathesis degradation of industrial rubber (models of rubber waste), and the oligomers transesterification. Thus, cis-1,4-polybutadiene (Mn= 9.1x105, Mw/Mn= 2.2) and styrene-butadiene block copolymers with 30% (Mn= 1.61x105; Mw/Mn= 1.3) and 21% wt styrene (Mn= 1.92x105; Mw/Mn= 1.4) were degraded via metathesis with soybean oil as chain transfer agent (CTA) and green solvent; using [(PCy3)2Cl2Ru=CHPh] and [(1,3-diphenyl-4,5-dihydroimidazol-2-ylidene)(PCy3)Ru=CHPh] catalysts. Afterwards, the products were transesterified by basic homogeneous catalysis. Before transesterification, the polystyrene microblocks (Mn= 16,761; Mw/Mn= 1.2) were isolated. Finally, the biofuels obtained (BO) were purified, characterized and showed similar properties to standards biodiesel (SB) (Norms: EN 14214-03 and ASTM D6751-02), i.e. (SB / BO): molecular weight [Daltons] (570 / 543-596), density [g/cm3] (0.86-0.90 / 0.88), kinematic viscosity [mm2/s] (1.90-6.0 / 3.5-4.5), iodine (97 / 97-98) and cetane number (Min.47 / 56-58).

Keywords: biofuels, industrial rubber, metathesis, vegetable oils

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4684 Essential Oil Composition and Antimicrobial Activity of Rosmarinus officinalis L. Grown in Algeria (Djelfa)

Authors: Samah Lakehal, A. Meliani, F. Z. Benrebiha, C. Chaouia

Abstract:

In the last few years, due to the misuse of antibiotics and an increasing incidence of immunodeficiency-related diseases, the development of microbial drug resistance has become more and more of a pressing problem. Recently, natural products from medicinal plants represent a fertile ground for the development of novel antibacterial agents. Plants essential oils have come more into the focus of phytomedicine. The present study describes antimicrobial activity of Rosmarinus officinalis L. essential oil known medicinally for its powerful antibacterial properties. The essential oil of rosemary obtained by hydrodistillation (using Clevenger type apparatus) growing in Algeria (Djelfa city of south Algeria) was investigated by GC-MS. The essential oil yield of the study was 1.4 %. The major components were found to be camphor, camphene, 1,8-cineole. The essential oil has been tested for antimicrobial activity against eight bacteria (Gram-negative and Gram-positive), and three fungi including Candida albicans. Inhibition of growth was tested by the agar diffusion method based on the determination of the diameter of inhibition. The oil was found to have significant antibacterial activity and therefore can be used as a natural antimicrobial agent for the treatment of several infectious diseases caused by those germs, which have developed resistance to antibiotics.

Keywords: antimicrobial activity, Rosmarinus officinalis L., essential oils, GC/MS, camphor

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4683 Illegitimate Pain and Ideology: Building a Theoretical Model for Future Analyses

Authors: J. Scott Kenney

Abstract:

Not all pain is created equal. In recent decades, the concept of Illegitimate pain has begun to shed light on the phenomena of emotional and physical pain that is misunderstood, neglected, or stigmatized, broadly conceptualized along dimensions of relative legitimation and physicality. Yet, beyond a pioneering study of the suffering of closeted LGBTQ + individuals, along with an analysis of the pains experienced by students at a religious boarding school, there has been insufficient attention to what lies behind such marginalized suffering beyond the original claim that it relates to broad interpretive standards and structured power relations, mediated through interaction in various groups/settings. This paper seeks to delve theoretically into this underdeveloped terrain. Building on earlier work, it takes direct aim at the definitional aspect that lies analytically prior to such matters, theoretically unpacking the role of ideology. Following a general introduction focused on theoretical relationships between social structure, power, and ideas, the paper reviews a range of sociological literature on relevant matters. After condensing the insights from these various literatures into a series of theoretical statements, the paper analytically engages with these to articulate a series of theoretical and methodological elaborations intended to practically assist researchers in empirically examining such matters in today's complex social environment.

Keywords: deviance, ideology, illegitimate pain, social theory, victimization

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4682 The Characteristics of the Chairman of Board of Directors That Are Associated with Better Levels of Performance

Authors: Abilio Pires Zacarias

Abstract:

Analyzing company boards of directors is a relevant and timely topic. As the representative of shareholders, the board is the most senior management body of this type of company. Therefore, ascertaining the best kind of candidates to nominate, namely the most appropriate characteristics for leading the board to achieve better levels of performance, is certainly of great interest. The companies selected for this study were the 1,000 largest non-financial companies and the 100 largest financial companies in Portugal according to the Instituto Nacional de Estatística for 2010. The information stemmed from a questionnaire addressed to the person in charge of daily company management and then processed through STATA 17 with the multivariate analysis of variables - MANOVA. The study may correspondingly report that the vast majority of boards in the sample operate a dual leadership structure. By in terms of its prevalence, unitary leadership represents only a minority. Agency theory and stewardship theory postulate different characteristics for the ideal chairman but neither receive confirmation from our results. On the other hand, our findings do validate the behavioral theory of firms (BToF), concluding that experience is associated with organizational performance. This study is also relevant due to its analysis of companies not listed on the financial markets not only because of their weighting in the economy but also because they remain only very poorly studied in this field and thus also correspondingly contributing to deepening the literature.

Keywords: agency theory, behavioral theory of the firm, board of directors, corporate governance, stewardship theory

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4681 Production of Lignocellulosic Enzymes by Bacillus safensis LCX Using Agro-Food Wastes in Solid State Fermentation

Authors: Abeer A. Q. Ahmed, Tracey McKay

Abstract:

The increasing demand for renewable fuels and chemicals is pressuring manufacturing industry toward finding more sustainable cost-effective resources. Lignocellulose, such as agro-food wastes, is a suitable equivalent to petroleum for fine chemicals and fuels production. The complex structure of lignocellulose, however, requires a variety of enzymes in order to degrade its components into their respective building blocks that can be used further for the production of various value added products. This study aimed to isolate bacterial strain with the ability to produce a variety of lignocellulosic enzymes. One bacterial isolate was identified by 16S rRNA gene sequencing and phylogenetic analysis as Bacillus safensis LCX found to have CMCase, xylanase, manganese peroxidase, lignin peroxidase, and laccase activities. The enzymes production was induced by growing Bacillus safensis LCX in solid state fermentation using wheat straw, wheat bran, and corn stover. The activities of enzymes were determined by specific colorimetric assays. This study presents Bacillus safensis LCX as a promising source for lignocellulosic enzymes. These findings can extend the knowledge on agro-food wastes valorization strategies toward a sustainable production of fuels and chemicals.

Keywords: Bacillus safensis LCX, high valued chemicals, lignocellulosic enzymes, solid state fermentation

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4680 Design of Cylindrical Crawler Robot Inspired by Amoeba Locomotion

Authors: Jun-ya Nagase

Abstract:

Recently, the need of colonoscopy is increasing because of the rise of colonic disorder including cancer of the colon. However, current colonoscopy depends on doctor's skill strongly. Therefore, a large intestine endoscope that does not depend on the techniques of a doctor with high safety is required. In this research, we aim at development a novel large intestine endoscope that can realize safe insertion without specific techniques. A wheel movement type robot, a snake-like robot and an earthworm-like robot are all described in the relevant literature as endoscope robots that are currently studied. Among them, the tracked crawler robot can travel by traversing uneven ground flexibly with a crawler belt attached firmly to the ground surface. Although conventional crawler robots have high efficiency and/or high ground-covering ability, they require a comparatively large space to move. In this study, a small cylindrical crawler robot inspired by amoeba locomotion, which does not need large space to move and which has high ground-covering ability, is proposed. In addition, we developed a prototype of the large intestine endoscope using the proposed crawler mechanism. Experiments have demonstrated smooth operation and a forward movement of the robot by application of voltage to the motor. This paper reports the structure, drive mechanism, prototype, and experimental evaluation.

Keywords: tracked-crawler, endoscopic robot, narrow path, amoeba locomotion.

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4679 Sustainable Balanced Scorecard for Kaizen Evaluation: Comparative Study between Egypt and Japan

Authors: Ola I. S. El Dardery, Ismail Gomaa, Adel R.M. Rayan, Ghada El Khayat, Sara H. Sabry

Abstract:

Continuous improvement activities are becoming a key factor of the success of any organization, those improvement activities include but not limited to kaizen, six sigma, lean projects, and continuous improvement projects. Kaizen is a Japanese philosophy of continuous improvement by making small incremental changes to improve an organization’s performance, reduce costs, reduce delay time, reduce waste in production, etc. This study aims at proposing a new measuring technique for kaizen activities using a Sustainable balanced scorecard structure. A survey questionnaire was developed and introduced to kaizen participants in both Egypt and Japan with the purpose of allocating key performance indicators for both kaizen process (critical success factors) and result (kaizen benefits) into the five perspectives of sustainable balanced scorecard. The study contributes to the literature by presenting a new kaizen measurement of both kaizen process and results, that will illuminate the benefits of using kaizen. Also, the presented measurement can help in the sustainability of kaizen implementation. Determining the combination of the proper kaizen measures could be used by any industry whether service or manufacturing to better measure kaizen activates. The comparison between Japanese measures, as the leaders of kaizen philosophy, and Egyptian measures will help recommending better practices of kaizen in Egypt, and contributing to the 2030 sustainable development goals.

Keywords: continuous improvements, kaizen, performance, sustainable balanced scorecard

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4678 Acoustic Analysis of Ball Bearings to Identify Localised Race Defect

Authors: M. Solairaju, Nithin J. Thomas, S. Ganesan

Abstract:

Each and every rotating part of a machine element consists of bearings within its structure. In particular, the rolling element bearings such as cylindrical roller bearing and deep groove ball bearings are frequently used. Improper handling, excessive loading, improper lubrication and sealing cause bearing damage. Hence health monitoring of bearings is an important aspect for radiation pattern of bearing vibration is computed using the dipole model. Sound pressure level for defect-free and race defect the prolonged life of machinery and auto motives. This paper presents modeling and analysis of Acoustic response of deep groove ball bearing with localized race defects. Most of the ball bearings, especially in machine tool spindles and high-speed applications are pre-loaded along an axial direction. The present study is carried out with axial preload. Based on the vibration response, the orbit motion of the inner race is studied, and it was found that the oscillation takes place predominantly in the axial direction. Simplified acoustic is estimated. Acoustic response shows a better indication in identifying the defective bearing. The computed sound signal is visualized in diagrammatic representation using Symmetrised Dot Pattern (SDP). SDP gives better visual distinction between the defective and defect-free bearing

Keywords: bearing, dipole, noise, sound

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4677 Reduction of Aerodynamic Drag Using Vortex Generators

Authors: Siddharth Ojha, Varun Dua

Abstract:

Classified as one of the most important reasons of aerodynamic drag in the sedan automobiles is the fluid flow separation near the vehicle’s rear end. To retard the separation of flow, bump-shaped vortex generators are being tested for its implementation to the roof end of a sedan vehicle. Frequently used in the aircrafts to prevent the separation of fluid flow, vortex generators themselves produce drag, but they also substantially reduce drag by preventing flow separation at the downstream. The net effects of vortex generators can be calculated by summing the positive and negative impacts and effects. Since this effect depends on dimensions and geometry of vortex generators, those present on the vehicle roof are optimized for maximum efficiency and performance. The model was tested through ANSYS CFD analysis and modeling. The model was tested in the wind tunnel for observing it’s properties such as aerodynamic drag and flow separation and a major time lag was gained by employing vortex generators in the scaled model. Major conclusions which were recorded during the analysis were a substantial 24% reduction in the aerodynamic drag and 14% increase in the efficiency of the sedan automobile as the flow separation from the surface is delayed. This paper presents the results of optimization, the effect of vortex generators in the flow field and the mechanism by which these effects occur and are regulated.

Keywords: aerodynamics, aerodynamic devices, body, computational fluid dynamics (CFD), flow visualization

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4676 An Assessment of the Effects of Social Conflicts on Tourism in Plateau State, Nigeria: Case Study of Jos Crisis on Hill Station Hotel

Authors: Audu Aly Fada, Adejoh Apeh Matthew

Abstract:

This research assesses the effects of social conflicts on tourism products in Plateau State. It was specifically set out to find out the major causes of social conflicts in Jos, evaluate the effects of social conflicts on the influx of tourists to Hill station hotel Jos, and the impact on revenue generation of the hotel. To achieve these objectives research questions were formulated and a sample of 30 hotel staff was selected as the respondents. Data collected were organized and analyzed using tables, percentages and mean statistics. It was found that the hospitality and tourism industry was adversely affected. The crisis brought about a decline in the number of tourist arrivals, increase in cancelled bookings, a decrease in the average length of stay of tourists and the average room occupancy. Peace is the best friend of travel and tourism, while war and insecurity are among its worst enemies. It is recommended that all stakeholders involved in tourism administration should device safer environment that supports continued patronage by providing modern security apparatus. In the same spirit, government as the main stake-holder in security provision should do more than paying lip service to guarantee security and safety of lives and properties.

Keywords: social conflict, crisis, security, tourism development

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4675 Impact of Different Tillage Practices on Soil Health Status: Carbon Storage and Pools, Soil Aggregation, and Nutrient Use

Authors: Denis Constantin Topa, Irina Gabriela Cara, Gerard Jitareanu

Abstract:

Tillage is a fundamental soil practice with different soil disturbance intensities and unique implications in soil organic carbon, soil structure, and nutrient dynamics. However, the implication of tillage practice on soil organic carbon and soil health is complex and specific to the context. it study evaluated soil health status based on soil carbon sequestration and pools, soil aggregation, and nutrient use under two different tillage practices: conventional and minimum tillage. The results of our study are consistent with the hypothesis that, over time, minimum tillage typically boosts soil health in the 0-10 cm soil layer. Compared to the conventional practice (19.36 t C ha-1) there was a significant accumulation of soil organic carbon (0-30 cm) in the minimum-tillage practice (23.21 t C ha-1). Below 10 cm depth, the soil organic carbon stocks are close to that of the conventional layer (0-30 cm). Soil aggregate stability was improved under conservative tillage, due to soil carbon improvement which facilitated a greater volume of mesopores and micropores. Total nitrogen (TN), available potassium (AK) and phosphorus (AP) content in 0-10 cm depth under minimum-tillage practice were 26%, 6% and 32%, greater respectively, compared to the conventional treatment. Overall, the TN, AP and AK values decreased with depth within the soil profiles as a consequence of soil practice and minimum disturbance. The data show that minimum tillage is a sustainable and effective management practice that maintain soil health with soil carbon increase and efficient nutrient use.

Keywords: minimum tillage, conventional tillage, soil organic carbon, nutrients, soil aggregation, soil health

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4674 Effect of Pomegranate (Punica granatum) Seed Oil on Keratinocytes in Patients with Atopic Dermatitis

Authors: Fardis Teifoori, Mehdi Dehghani, Idoia Postigo, Jorge Martinez

Abstract:

Introduction: Many skin disorders, such as atopic dermatitis (AD), is characterized by inflammation, infection, and hyperplasia. In this work, keratinocytes from AD patients are used to study the pomegranate seed oil properties for skin care. Material and methods: Isolated keratinocytes from patients with AD were cultured and stimulated by IL-9 (20 ng/ml) and TNF-α (50ng/ml) for 48h to induce vascular endothelial growth factor (VEGF) and Regulated upon activation, normal T cell expressed and secreted (RANTES) production, respectively, in the presence of different concentrations of pomegranate seed oil (20, 50, 100, and 200 µM). Finally, the concentrations of RANTES and VEGF in the cell culture supernatant were quantified according to the standard protocol of commercial ELISA kits. Results: The results indicated that pomegranate seed oil concentrations of 50, 100, and 200 µM could significantly inhibit the production of VEGF and RANTES by stimulating keratinocytes with IL-9 (20 ng/ml) and TNF-α (50ng/ml), respectively. The decrease in VEGF and RANTES concentration in the presence of the pomegranate seed oil concentrations of 20 and 50 uM was not significant. Conclusion: It was concluded that pomegranate seed oil (PSO) counteracts atopic dermatitis conditions dose-dependently: with the highest effect at the concentration of 200 µM. We suggest that the inexpensive and easily available pomegranate seed oil is a good candidate for cosmetics and clinical utilization for skin care.

Keywords: atopic dermatitis, pomegranate, Punica granatum, RANTES, VEGF

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4673 Thymoquinone Prevented the Development of Symptoms in Animal Model of Parkinson’s Disease

Authors: Kambiz Hassanzadeh, Seyedeh Shohreh Ebrahimi, Shahrbanoo Oryan, Arman Rahimmi, Esmael Izadpanah

Abstract:

Parkinson’s disease is one of the most prevalent neurodegenerative diseases which occurs in elderly. There are convincing evidences that oxidative stress has an important role in both the initiation and progression of Parkinson’s disease. Thymoquinone (TQ) is shown to have antioxidant and anti-inflammatory properties in invitro and invivo studies. It is well documented that TQ acts as a free radical scavenger and prevents the cell damage. Therefore this study aimed to evaluate the effect of TQ on motor and non-motor symptoms in animal model of Parkinson’s disease. Male Wistar rats (10-12 months) received rotenone (1mg/kg/day, sc) to induce Parkinson’s disease model. Pretreatment with TQ (7.5 and 15 mg/kg/day, po) was administered one hour before the rotenone injection. Three motor tests (rotarod, rearing and bar tests) and two non-motor tests (forced swimming and elevated plus maze) were performed for behavioral assessment. Our results indicated that TQ significantly ameliorated the rotenone-induced motor dysfunction in rotarod and rearing tests also it could prevent the non-motor dysfunctions in forced swimming and elevated plus maze tests. In conclusion we found that TQ delayed the Parkinson's disease induction by rotenone and this effect might be related to its proved antioxidant effect.

Keywords: Parkinson's disease, thymoquinone, motor and non-motor symptoms, neurodegenerative disease

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4672 QSRR Analysis of 17-Picolyl and 17-Picolinylidene Androstane Derivatives Based on Partial Least Squares and Principal Component Regression

Authors: Sanja Podunavac-Kuzmanović, Strahinja Kovačević, Lidija Jevrić, Evgenija Djurendić, Jovana Ajduković

Abstract:

There are several methods for determination of the lipophilicity of biologically active compounds, however chromatography has been shown as a very suitable method for this purpose. Chromatographic (C18-RP-HPLC) analysis of a series of 24 17-picolyl and 17-picolinylidene androstane derivatives was carried out. The obtained retention indices (logk, methanol (90%) / water (10%)) were correlated with calculated physicochemical and lipophilicity descriptors. The QSRR analysis was carried out applying principal component regression (PCR) and partial least squares regression (PLS). The PCR and PLS model were selected on the basis of the highest variance and the lowest root mean square error of cross-validation. The obtained PCR and PLS model successfully correlate the calculated molecular descriptors with logk parameter indicating the significance of the lipophilicity of compounds in chromatographic process. On the basis of the obtained results it can be concluded that the obtained logk parameters of the analyzed androstane derivatives can be considered as their chromatographic lipophilicity. These results are the part of the project No. 114-451-347/2015-02, financially supported by the Provincial Secretariat for Science and Technological Development of Vojvodina and CMST COST Action CM1105.

Keywords: androstane derivatives, chromatography, molecular structure, principal component regression, partial least squares regression

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4671 The Diffusion of Membrane Nanodomains with Specific Ganglioside Composition

Authors: Barbora Chmelova, Radek Sachl

Abstract:

Gangliosides are amphipathic membrane lipids. Due to the composition of bulky oligosaccharide chains containing one or more sialic acids linked to the hydrophobic ceramide base, gangliosides are classified among glycosphingolipids. This unique structure induces a high self-aggregating tendency of gangliosides and, therefore, the formation of nanoscopic clusters called nanodomains. Gangliosides are preferentially present in an extracellular membrane leaflet of all human tissues and thus have an impact on a huge number of biological processes, such as intercellular communication, cell signalling, membrane trafficking, and regulation of receptor activity. Defects in their metabolism, impairment of proper ganglioside function, or changes in their organization lead to serious health conditions such as Alzheimer´s and Parkinson´s diseases, autoimmune diseases, tumour growth, etc. This work mainly focuses on ganglioside organization into nanodomains and their dynamics within the plasma membrane. Current research investigates static ganglioside nanodomains characterization; nevertheless, the information about their diffusion is missing. In our study, fluorescence correlation spectroscopy is implemented together with stimulated emission depletion (STED-FCS), which combines the diffraction-unlimited spatial resolution with high temporal resolution. By comparison of the experiments performed on model vesicles containing 4 % of either GM1, GM2, or GM3 and Monte Carlo simulations of diffusion on the plasma membrane, the description of ganglioside clustering, diffusion of nanodomains, and even diffusion of ganglioside molecules inside investigated nanodomains are described.

Keywords: gangliosides, nanodomains, STED-FCS, flourescence microscopy, membrane diffusion

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4670 Synthesis of Polyvinyl Alcohol Encapsulated Ag Nanoparticle Film by Microwave Irradiation for Reduction of P-Nitrophenol

Authors: Supriya, J. K. Basu, S. Sengupta

Abstract:

Silver nanoparticles have caught a lot of attention because of its unique physical and chemical properties. Silver nanoparticles embedded in polyvinyl alcohol (PVA/Ag) free-standing film have been prepared by microwave irradiation in few minutes. PVA performed as a reducing agent, stabilizing agents as well as support for silver nanoparticles. UV-Vis spectrometry, scanning transmission electron (SEM) and transmission electron microscopy (TEM) techniques affirmed the reduction of silver ion to silver nanoparticles in the polymer matrix. Effect of irradiation time, the concentration of PVA and concentration of silver precursor on the synthesis of silver nanoparticle has been studied. Particles size of silver nanoparticles decreases with increase in irradiation time. Concentration of silver nanoparticles increases with increase in concentration of silver precursor. Good dispersion of silver nanoparticles in the film has been confirmed by TEM analysis. Particle size of silver nanoparticle has been found to be in the range of 2-10nm. Catalytic property of prepared silver nanoparticles as a heterogeneous catalyst has been studied in the reduction of p-Nitrophenol (a water pollutant) with >98% conversion. From the experimental results, it can be concluded that PVA encapsulated Ag nanoparticles film as a catalyst shows better efficiency and reusability in the reduction of p-Nitrophenol.

Keywords: biopolymer, microwave irradiation, silver nanoparticles, water pollutant

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4669 Motion Detection Method for Clutter Rejection in the Bio-Radar Signal Processing

Authors: Carolina Gouveia, José Vieira, Pedro Pinho

Abstract:

The cardiopulmonary signal monitoring, without the usage of contact electrodes or any type of in-body sensors, has several applications such as sleeping monitoring and continuous monitoring of vital signals in bedridden patients. This system has also applications in the vehicular environment to monitor the driver, in order to avoid any possible accident in case of cardiac failure. Thus, the bio-radar system proposed in this paper, can measure vital signals accurately by using the Doppler effect principle that relates the received signal properties with the distance change between the radar antennas and the person’s chest-wall. Once the bio-radar aim is to monitor subjects in real-time and during long periods of time, it is impossible to guarantee the patient immobilization, hence their random motion will interfere in the acquired signals. In this paper, a mathematical model of the bio-radar is presented, as well as its simulation in MATLAB. The used algorithm for breath rate extraction is explained and a method for DC offsets removal based in a motion detection system is proposed. Furthermore, experimental tests were conducted with a view to prove that the unavoidable random motion can be used to estimate the DC offsets accurately and thus remove them successfully.

Keywords: bio-signals, DC component, Doppler effect, ellipse fitting, radar, SDR

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4668 The Postcolonial Everyday: the Construction of Daily Barriers in the Experience of Asylum Seekers and Refugees in the UK

Authors: Sarah Elmammeri

Abstract:

This paper will represent the postcolonial every day in the journey of asylum seekers through the asylum process in the UK. It represents everyday borders, which are defined as everyday barriers, and obstacles facing asylum seekers and refugees in the host country. These everyday barriers can be legal, financial, social and educational under the umbrella of the racialized administrative border creating a package. The arguments build on a set of 21 semi-structured interviews in English and Arabic. The interviews were conducted in the UK, online via zoom lasting between 25 minutes and 2 hours with asylum seekers, refugees, Non-governmental organisations workers and volunteers. The interviews focus on the meaning of borders both physical and metaphorical and ways to challenge the ongoing postcolonial everyday border practices. The findings conclude that these barriers are there deliberately and intentionally to target asylum seekers and limit their legal right to claim asylum in a form of policy and regulations. People in the asylum process, NGO workers, and refugees relate to this aspect of the everyday borders. Second, these barriers come intertwined together creating a structure that interferes with the daily life of an asylum seeker and later affects people with refugee status creating racialised barriers starting with the structural and official form of it: the asylum process. These structural barriers will be linked forming a multi-level barrier enhancing the racialisation of people who are categorised and selected.

Keywords: everyday borders, asylum policies, inclusion and exclusion, refugees and asylum seekers

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4667 Numerical Study on the Performance of Upgraded Victorian Brown Coal in an Ironmaking Blast Furnace

Authors: Junhai Liao, Yansong Shen, Aibing Yu

Abstract:

A 3D numerical model is developed to simulate the complicated in-furnace combustion phenomena in the lower part of an ironmaking blast furnace (BF) while using pulverized coal injection (PCI) technology to reduce the consumption of relatively expensive coke. The computational domain covers blowpipe-tuyere-raceway-coke bed in the BF. The model is validated against experimental data in terms of gaseous compositions and coal burnout. Parameters, such as coal properties and some key operational variables, play an important role on the performance of coal combustion. Their diverse effects on different combustion characteristics are examined in the domain, in terms of gas compositions, temperature, and burnout. The heat generated by the combustion of upgraded Victorian brown coal is able to meet the heating requirement of a BF, hence making upgraded brown coal injected into BF possible. It is evidenced that the model is suitable to investigate the mechanism of the PCI operation in a BF. Prediction results provide scientific insights to optimize and control of the PCI operation. This model cuts the cost to investigate and understand the comprehensive combustion phenomena of upgraded Victorian brown coal in a full-scale BF.

Keywords: blast furnace, numerical study, pulverized coal injection, Victorian brown coal

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4666 Domain Switching Characteristics of Lead Zirconate Titanate Piezoelectric Ceramic

Authors: Mitsuhiro Okayasu

Abstract:

To better understand the lattice characteristics of lead zirconate titanate (PZT) ceramics, the lattice orientations and domain-switching characteristics have been directly examined during loading and unloading using various experimental techniques. Upon loading, the PZT ceramics are fractured linear and nonlinearly during the compressive loading process. The strain characteristics of the PZT ceramic were directly affected by both the lattice and domain switching strain. Due to the piezoelectric ceramic, electrical activity of lightning-like behavior occurs in the PZT ceramics, which attributed to the severe domain-switching leading to weak piezoelectric property. The characteristics of domain-switching and reverse switching are detected during the loading and unloading processes. The amount of domain-switching depends on the grain, due to different stress levels. In addition, two patterns of 90˚ domain-switching systems are characterized, namely (i) 90˚ turn about the tetragonal c-axis and (ii) 90˚ rotation of the tetragonal a-axis. In this case, PZT ceramic was loaded by the thermal stress at 80°C. Extent of domain switching is related to the direction of c-axis of the tetragonal structure, e.g., that axis, orientated close to the loading direction, makes severe domain switching. It is considered that there is 90˚ domain switching, but in actual, the angle of domain switching is less than 90˚, e.g., 85.4° ~ 90.0°. In situ TEM observation of the domain switching characteristics of PZT ceramic has been conducted with increasing the sample temperature from 25°C to 300°C, and the domain switching like behavior is directly observed from the lattice image, where the severe domain switching occurs less than 100°C.

Keywords: PZT, lead zirconate titanate, piezoelectric ceramic, domain switching, material property

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4665 Effective Governance and Administrative Structures for Virile Trade Unions and Cordial Labour Relations

Authors: Theophilius Adekunle Tinuoye

Abstract:

Trade unions are groups formed essentially to promote, articulate and enhance the welfare of workers. They are expected to defend the workers interests and participate actively in workplace exchanges. But for trade unions to function effectively and actualize their lofty aspirations in the context of the current dynamic and ever-changing industrial relations context, they must not only have qualified and competent leaders, but also flexible and effective structure, systems, organograms, constitution, and administrative processes in place to compliment their policies and programmes. An important aspect of industrial relations is the existence of cordial tripartite or bipartite interactions between stakeholders and other social partners that are indispensable to the creation of positive and mutually beneficial exchanges and outcomes. This paper canvassed that unions must be structurally viable and administratively cohesive in order to be effective, pragmatic, functional and remain relevant. It also argued that weak, structurally deficient and less organized unions often find it immensely difficult to actualize workers goals. Finally, it outlined basic principles that will enhance union administration, guarantee that unions will continue to satisfy the yearnings of its members in these trying times and finally foster peaceful industrial relations climate and cordial labor relations between trade unions, employers /management and government.

Keywords: governance, labor relations, trade unions, workers

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4664 Cladding Technology for Metal-Hybrid Composites with Network-Structure

Authors: Ha-Guk Jeong, Jong-Beom Lee

Abstract:

Cladding process is very typical technology for manufacturing composite materials by the hydrostatic extrusion. Because there is no friction between the metal and the container, it can be easily obtained in uniform flow during the deformation. The general manufacturing process for a metal-matrix composite in the solid state, mixing metal powders and ceramic powders with a suited volume ratio, prior to be compressed or extruded at the cold or hot condition in a can. Since through a plurality of unit processing steps of dispersing the materials having a large difference in their characteristics and physical mixing, the process is complicated and leads to non-uniform dispersion of ceramics. It is difficult and hard to reach a uniform ideal property in the coherence problems at the interface between the metal and the ceramic reinforcements. Metal hybrid composites, which presented in this report, are manufactured through the traditional plastic deformation processes like hydrostatic extrusion, caliber-rolling, and drawing. By the previous process, the realization of uniform macro and microstructure is surely possible. In this study, as a constituent material, aluminum, copper, and titanium have been used, according to the component ratio, excellent characteristics of each material were possible to produce a metal hybrid composite that appears to maximize. MgB₂ superconductor wire also fabricated via the same process. It will be introduced to their unique artistic and thermal characteristics.

Keywords: cladding process, metal-hybrid composites, hydrostatic extrusion, electronic/thermal characteristics

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