Search results for: queue size distribution at a random epoch
4860 Deciphering Tumor Stroma Interactions in Retinoblastoma
Authors: Rajeswari Raguraman, Sowmya Parameswaran, Krishnakumar Subramanian, Jagat Kanwar, Rupinder Kanwar
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Background: Tumor microenvironment has been implicated in several cancers to regulate cell growth, invasion and metastasis culminating in outcome of therapy. Tumor stroma consists of multiple cell types that are in constant cross-talk with the tumor cells to favour a pro-tumorigenic environment. Not much is known about the existence of tumor microenvironment in the pediatric intraocular malignancy, Retinoblastoma (RB). In the present study, we aim to understand the multiple stromal cellular subtypes and tumor stromal interactions expressed in RB tumors. Materials and Methods: Immunohistochemistry for stromal cell markers CD31, CD68, alpha-smooth muscle (α-SMA), vimentin and glial fibrillary acidic protein (GFAP) was performed on formalin fixed paraffin embedded tissues sections of RB (n=12). The differential expression of stromal target molecules; fibroblast activation protein (FAP), tenascin-C (TNC), osteopontin (SPP1), bone marrow stromal antigen 2 (BST2), stromal derived factor 2 and 4 (SDF2 and SDF4) in primary RB tumors (n=20) and normal retina (n=5) was studied by quantitative reverse transcriptase polymerase chain reaction (qRT-PCR) and Western blotting. The differential expression was correlated with the histopathological features of RB. The interaction between RB cell lines (Weri-Rb-1, NCC-RbC-51) and Bone marrow stromal cells (BMSC) was also studied using direct co-culture and indirect co-culture methods. The functional effect of the co-culture methods on the RB cells was evaluated by invasion and proliferation assays. Global gene expression was studied by using Affymetrix 3’ IVT microarray. Pathway prediction was performed using KEGG and the key molecules were validated using qRT-PCR. Results: The immunohistochemistry revealed the presence of several stromal cell types such as endothelial cells (CD31+;Vim+/-); macrophages (CD68+;Vim+/-); Fibroblasts (Vim+; CD31-;CD68- );myofibroblasts (α-SMA+/ Vim+) and invading retinal astrocytes/ differentiated retinal glia (GFAP+; Vim+). A characteristic distribution of these stromal cell types was observed in the tumor microenvironment, with endothelial cells predominantly seen in blood vessels and macrophages near actively proliferating tumor or necrotic areas. Retinal astrocytes and glia were predominant near the optic nerve regions in invasive tumors with sparse distribution in tumor foci. Fibroblasts were widely distributed with rare evidence of myofibroblasts in the tumor. Both gene and protein expression revealed statistically significant (P<0.05) up-regulation of FAP, TNC and BST2 in primary RB tumors compared to the normal retina. Co-culture of BMSC with RB cells promoted invasion and proliferation of RB cells in direct and indirect contact methods respectively. Direct co-culture of RB cell lines with BMSC resulted in gene expression changes in ECM-receptor interaction, focal adhesion, IL-8 and TGF-β signaling pathways associated with cancer. In contrast, various metabolic pathways such a glucose, fructose and amino acid metabolism were significantly altered under the indirect co-culture condition. Conclusion: The study suggests that the close interaction between RB cells and the stroma might be involved in RB tumor invasion and progression which is likely to be mediated by ECM-receptor interactions and secretory factors. Targeting the tumor stroma would be an attractive option for redesigning treatment strategies for RB.Keywords: gene expression profiles, retinoblastoma, stromal cells, tumor microenvironment
Procedia PDF Downloads 3864859 Raman and Dielectric Relaxation Investigations of Polyester-CoFe₂O₄ Nanocomposites
Authors: Alhulw H. Alshammari, Ahmed Iraqi, S. A. Saad, T. A. Taha
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In this work, we present for the first time the study of Raman spectra and dielectric relaxation of polyester polymer-CoFe₂O₄ (5.0, 10.0, 15.0, and 20.0 wt%) nanocomposites. Raman spectroscopy was applied as a sensitive structural identification technique to characterize the polyester-CoFe₂O₄ nanocomposites. The images of AFM confirmed the uniform distribution of CoFe₂O₄ inside the polymer matrix. Dielectric relaxation was employed as an important analytical technique to obtain information about the ability of the polymer nanocomposites to store and filter electrical signals. The dielectric relaxation analyses were carried out on the polyester-CoFe₂O₄ nanocomposites at different temperatures. An increase in dielectric constant ε₁ was observed for all samples with increasing temperatures due to the alignment of the electric dipoles with the applied electric field. In contrast, ε₁ decreased with increasing frequency. This is attributed to the difficulty for the electric dipoles to follow the electric field. The α relaxation peak that appeared at a high frequency shifted to higher frequencies when increasing the temperature. The activation energies for Maxwell-Wagner Sillar (MWS) changed from 0.84 to 1.01 eV, while the activation energies for α relaxations were 0.54 – 0.94 eV. The conduction mechanism for the polyester- CoFe₂O₄ nanocomposites followed the correlated barrier hopping (CBH) model.Keywords: AC conductivity, activation energy, dielectric permittivity, polyester nanocomposites
Procedia PDF Downloads 1204858 Perception and Effect of Gender-Based Violence on Sustainable Development and Education of Girl-Child in Southwestern Nigeria
Authors: Afolabi Comfort Yemisi
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Gender-based violence remains a serious threat to the growth, health, and safety of women and girls globally, including Nigeria. The rising violence of various shades of violence, especially against women and girls in the guise of cultural preservation, raised serious concerns. The challenge of this harmful gender narrative is more critical in attaining the Sustainable Development Goals and Goal 4 (Quality Education) in Nigeria. The study investigated the perception and effects of gender-based violence on sustainable development and education of the girl-child in Southwestern Nigeria. Primary and Secondary data were used for the study. Primary data were obtained using a structured questionnaire administered to young females in tertiary institutions, secondary schools, non-governmental organizations, and government institutions dealing with gender-based violence in the study area, while the secondary data were sourced from journals, books and dailies. A multistage random sampling technique was employed to select a sample of 360 respondents who completed the questionnaire for the study. Descriptive statistics and regression analysis were applied to the data collected. The result revealed a high prevalence of gender-based violence, and it was perceived to be culturally motivated. Sexual violence, sexual harassment and psychological violence were the significant forms of gender-based violence that adversely affected the Sustainable Development Goal 4. The result further revealed that loss of concentration, shame and depression, school drop-out, poor academic performance and inferiority complex were the major effects of gender-based violence on the education of girl-child in the study area. The study recommended that to avert catastrophic damages and adverse effects of gender-based violence on the girl-child, there is a need for thorough awareness and sensitization programmes to build their resilience. Also, enforcement of established laws against gender-based violence by both government and non-governmental institutions is sacrosanct.Keywords: perception, effects, gender-based violence, sustainable development, education, girl-child, sensitisation
Procedia PDF Downloads 204857 Modeling Competition Between Subpopulations with Variable DNA Content in Resource-Limited Microenvironments
Authors: Parag Katira, Frederika Rentzeperis, Zuzanna Nowicka, Giada Fiandaca, Thomas Veith, Jack Farinhas, Noemi Andor
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Resource limitations shape the outcome of competitions between genetically heterogeneous pre-malignant cells. One example of such heterogeneity is in the ploidy (DNA content) of pre-malignant cells. A whole-genome duplication (WGD) transforms a diploid cell into a tetraploid one and has been detected in 28-56% of human cancers. If a tetraploid subclone expands, it consistently does so early in tumor evolution, when cell density is still low, and competition for nutrients is comparatively weak – an observation confirmed for several tumor types. WGD+ cells need more resources to synthesize increasing amounts of DNA, RNA, and proteins. To quantify resource limitations and how they relate to ploidy, we performed a PAN cancer analysis of WGD, PET/CT, and MRI scans. Segmentation of >20 different organs from >900 PET/CT scans were performed with MOOSE. We observed a strong correlation between organ-wide population-average estimates of Oxygen and the average ploidy of cancers growing in the respective organ (Pearson R = 0.66; P= 0.001). In-vitro experiments using near-diploid and near-tetraploid lineages derived from a breast cancer cell line supported the hypothesis that DNA content influences Glucose- and Oxygen-dependent proliferation-, death- and migration rates. To model how subpopulations with variable DNA content compete in the resource-limited environment of the human brain, we developed a stochastic state-space model of the brain (S3MB). The model discretizes the brain into voxels, whereby the state of each voxel is defined by 8+ variables that are updated over time: stiffness, Oxygen, phosphate, glucose, vasculature, dead cells, migrating cells and proliferating cells of various DNA content, and treat conditions such as radiotherapy and chemotherapy. Well-established Fokker-Planck partial differential equations govern the distribution of resources and cells across voxels. We applied S3MB on sequencing and imaging data obtained from a primary GBM patient. We performed whole genome sequencing (WGS) of four surgical specimens collected during the 1ˢᵗ and 2ⁿᵈ surgeries of the GBM and used HATCHET to quantify its clonal composition and how it changes between the two surgeries. HATCHET identified two aneuploid subpopulations of ploidy 1.98 and 2.29, respectively. The low-ploidy clone was dominant at the time of the first surgery and became even more dominant upon recurrence. MRI images were available before and after each surgery and registered to MNI space. The S3MB domain was initiated from 4mm³ voxels of the MNI space. T1 post and T2 flair scan acquired after the 1ˢᵗ surgery informed tumor cell densities per voxel. Magnetic Resonance Elastography scans and PET/CT scans informed stiffness and Glucose access per voxel. We performed a parameter search to recapitulate the GBM’s tumor cell density and ploidy composition before the 2ⁿᵈ surgery. Results suggest that the high-ploidy subpopulation had a higher Glucose-dependent proliferation rate (0.70 vs. 0.49), but a lower Glucose-dependent death rate (0.47 vs. 1.42). These differences resulted in spatial differences in the distribution of the two subpopulations. Our results contribute to a better understanding of how genomics and microenvironments interact to shape cell fate decisions and could help pave the way to therapeutic strategies that mimic prognostically favorable environments.Keywords: tumor evolution, intra-tumor heterogeneity, whole-genome doubling, mathematical modeling
Procedia PDF Downloads 784856 Non-Equilibrium Synthesis and Structural Characterization of Magnetic FeCoPt Nanocrystalline Alloys
Authors: O. Crisan, A. D. Crisan, I. Mercioniu, R. Nicula, F. Vasiliu
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FePt-based systems are currently under scrutiny for their possible use as future materials for perpendicular magnetic recording. Another possible application is in the field of permanent magnets without rare-earths, magnets that are capable to operate at higher temperatures than the classic Nd-Fe-B magnets. Within this work, FeCoPt alloys prepared by rapid solidification from the melt are structurally and magnetically characterized. Extended transmission electron microscopy analysis shows the high degree of L10 ordering. X-ray diffraction is used to characterize the phase structure and to obtain the structural parameters of interest for L10 ordering. Co-existence of hard CoFePt and CoPt L10 phases with the soft fcc FePt phase is obtained within a refined microstructure made of alternatively disposed grains of around 5 to 20 nm in size. Magnetic measurements show increased remanence close to the parent L10 FePt phase and not so high coercivity due to the significant presence of the soft magnetic constituent phase. A Curie temperature of about 820K is reported for the FeCoPt alloy.Keywords: melt-spinning, FeCoPt alloys, high-resolution electron microscopy (HREM), ordered L10 structure
Procedia PDF Downloads 3224855 Influence of Shield Positions on Thermo/Fluid Performance of Pin Fin Heat Sink
Authors: Ramy H. Mohammed
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In heat sinks, the flow within the core exhibits separation and hence does not lend itself to simple analytical boundary layer or duct flow analysis of the wall friction. In this paper, I present some findings from an experimental and numerical study aimed to obtain physical insight into the influence of the presence of the shield and its position on the hydraulic and thermal performance of square pin fin heat sink without top by-pass. The variations of the Nusselt number and friction factor are obtained under varied parameters, such as the Reynolds number and the shield position. The numerical code is validated by comparing the numerical results with the available experimental data. It is shown that, there is a good agreement between the temperature predictions based on the model and the experimental data. Results show that, as the presence of the shield, the heat transfer of fin array is enhanced and the flow resistance increased. The surface temperature distribution of the heat sink base is more uniform when the dimensionless shield position equals to 1/3 or 2/3. The comprehensive performance evaluation approach based on identical pumping power criteria is adopted and shows that the optimum shield position is at x/l=0.43 where energy is saved.Keywords: shield, fin array, performance evaluation, heat transfer, energy
Procedia PDF Downloads 3104854 Viscoelastic Separation and Concentration of Candida Using a Low Aspect Ratio Microchannel
Authors: Seonggil Kim, Jeonghun Nam, Chae Seung Lim
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Rapid diagnosis of fungal infections is critical for rapid antifungal therapy. However, it is difficult to detect extremely low concentration fungi in blood sample. To address the limitation, separation and concentration of fungi in blood sample are required to enhance the sensitivity of PCR analysis. In this study, we demonstrated a sheathless separation and concentration of fungi, candida cells using a viscoelastic fluid. To validate the performance of the device, microparticle mixture (2 and 13 μm) was used, and those particles were successfully separated based on the size difference at high flow rate of 100 μl/min. For the final application, successful separation of the Candida cells from the white blood cells (WBCs) was achieved. Based on the viscoelastic lateral migration toward the equilibrium position, Candida cells were separated and concentrated by center focusing, while WBCs were removed by patterning into two streams between the channel center and the sidewalls. By flow cytometric analysis, the separation efficiency and the purity were evaluated as ~99% and ~ 97%, respectively. From the results, the device can be the powerful tool for detecting extremely rare disease-related cells.Keywords: candida cells, concentration, separation, viscoelastic fluid
Procedia PDF Downloads 1984853 Gel-Based Autologous Chondrocyte Implantation (GACI) in the Knee: Multicentric Short Term Study
Authors: Shaival Dalal, Nilesh Shah, Dinshaw Pardiwala, David Rajan, Satyen Sanghavi, Charul Bhanji
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Autologous Chondrocyte Implantation (ACI) is used worldwide since 1998 to treat cartilage defect. GEL based ACI is a new tissue-engineering technique to treat full thickness cartilage defect with fibrin and thrombin as scaffold for chondrocytes. Purpose of this study is to see safety and efficacy of gel based ACI for knee cartilage defect in multiple centres with different surgeons. Gel-based Autologous Chondrocyte Implantation (GACI) has shown effectiveness in treating isolated cartilage defect of knee joint. Long term results are still needed to be studied. This study was followed-up up to two years and showed benefit to patients. All enrolled patients with a mean age of 28.5 years had an average defect size of3 square centimeters, and were grade IV as per ICRS grading. All patients were followed up several times and at several intervals at 6th week, 8th week, 11th week, 17th week, 29th week, 57th week after surgery. The outcomes were measured based on the IKDC (subjective and objective) and MOCART scores.Keywords: knee, chondrocyte, autologous chondrocyte implantation, fibrin gel based
Procedia PDF Downloads 3854852 Influence of Machining Process on Surface Integrity of Plasma Coating
Authors: T. Zlámal, J. Petrů, M. Pagáč, P. Krajkovič
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For the required function of components with the thermal spray coating, it is necessary to perform additional machining of the coated surface. The paper deals with assessing the surface integrity of Metco 2042, a plasma sprayed coating, after its machining. The selected plasma sprayed coating serves as an abradable sealing coating in a jet engine. Therefore, the spray and its surface must meet high quality and functional requirements. Plasma sprayed coatings are characterized by lamellar structure, which requires a special approach to their machining. Therefore, the experimental part involves the set-up of special cutting tools and cutting parameters under which the applied coating was machined. For the assessment of suitably set machining parameters, selected parameters of surface integrity were measured and evaluated during the experiment. To determine the size of surface irregularities and the effect of the selected machining technology on the sprayed coating surface, the surface roughness parameters Ra and Rz were measured. Furthermore, the measurement of sprayed coating surface hardness by the HR 15 Y method before and after machining process was used to determine the surface strengthening. The changes of strengthening were detected after the machining. The impact of chosen cutting parameters on the surface roughness after the machining was not proven.Keywords: machining, plasma sprayed coating, surface integrity, strengthening
Procedia PDF Downloads 2714851 Transnationalization Strategies of Danish Cinema: Susanne Bier, Lone Scherfig
Authors: Ebru Thwaites Diken
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This article analyzes the works of certain directors in Danish cinema, namely Susanne Bier and Lone Sherfig, in the context of transnationalisation of Danish cinema. It looks at how the films' narratives negotiate and reconstruct the local / national / regional and the global. Scholars such as Nestingen & Elkington (2005), Hjort (2010), Higbee and Lim (2010), Bondebjerg and Redvall (2011) address transnationalism of Danish cinema in terms of production and distribution processes and how film making trascends national boundaries. This paper employs a particular understanding of transnationalism - in terms of how ideas and characters travel - to analyze how the storytelling and style has evolved to connect the national, the regional and the global on the basis of the works of these two directors. Strategies such as Hollywoodization - i.e. focus on stardom and classical narration, adhering to conventional European genre formulas, producing Danish films in English language have been identifiable strategies in Danish cinema in the period after the 2000s. Susanne Bier and Lone Scherfig are significant for employing some of these strategies simultaneously. For this reason, this article will look at how these two directors have employed these strategies and negotiated the cultural boundaries and exchanges.Keywords: danish cinema, transnational cinema, susanne bier, lone scherfig, national cinema
Procedia PDF Downloads 734850 The Applicability of Western Environmental Criminology Theories to the Arabic Context
Authors: Nawaf Alotaibi, Andy Evans, Alison Heppenstall, Nick Malleson
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Throughout the last two decades, motor vehicle theft (MVT) has accounted for the largest proportion of property crime incidents in Saudi Arabia (SA). However, to date, few studies have investigated SA’s MVT problem. Those that have are primarily focused on the characteristics of car thieves, and most have overlooked any spatial-temporal distribution of MVT incidents and the characteristics of victims. This paper represents the first step in understanding this problem by reviewing the existing MVT studies contextualised within the theoretical frameworks developed in environmental criminology theories – originating in the West – and exploring to what extent they are relevant to the SA context. To achieve this, the paper has identified a range of key features in SA that are different from typical Western contexts, that could limit the appropriateness and capability of applying existing environmental criminology theories. Furthermore, despite these Western studies reviewed so far having introduced a number of explanatory variables for MVT rates, a range of significant elements are apparently absent in the current literature and this requires further analysis. For example, almost no attempts have been made to quantify the associations between the locations of vehicle theft, recovery of stolen vehicles, joyriding and traffic volume.Keywords: environmental criminology theories, motor vehicle theft, Saudi Arabia, spatial analysis
Procedia PDF Downloads 3014849 The Effect of Computerized Systems of Office Automation on Employees' Productivity Efficiency
Authors: Mohammad Hemmati, Mohammad Taban, Ali Yasini
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One of the factors that can play an important role in increasing productivity is the optimal use of information technology, which in this area today has a significant role to play in computer systems of office automation in organizations and companies. Therefore, this research has been conducted with the aim of investigating the effect of the relationship between computerized systems of office automation and the productivity of employees in the municipality of Ilam city. The statistical population of this study was 110 people. Using Cochran formula, the minimum sample size is 78 people. The present research is a descriptive-looking research in terms of the type of objective view. A questionnaire was used to collect data. To assess the reliability of variables, Cornbrash’s alpha coefficient was used, which was equal to 0.85; SPSS19 and Pearson test were used to analyze the data and test the hypothesis of the research. In this research, three hypotheses of the relationship between office automation with efficiency, performance, and effectiveness were investigated. The results showed a direct and positive relationship between the office automation system and the increase in the efficiency, effectiveness, and efficiency of employees, and there was no reason to reject these hypotheses.Keywords: efficiency, performance, effectiveness, automation
Procedia PDF Downloads 2204848 An Empirical Analysis of the Perception of First Time Voters in Pakistan on the Upcoming General Election 2018, Relationships between Voters and Factors That Affect Voter Priorities
Authors: Syed Muhammad Wajih ul Hassan
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This research looks at the perception of first-time voters in Pakistan on the political dynamics of the country. This paper shall review the researches that were conducted by Gallup Pakistan and compare it with our findings regarding the voter behavior and factors that affect the priorities of the voters. A country where democracy has just completed its 2 consecutive tenures for the first time, one would always want to know about the voting trends among youth where young population makes 60% of the population in the country. In that case, it is not only a big task to find out voter patterns and trends voters might adhere to while a general election is approaching. Also, the paper discovers the psychology of young Pakistani voters on the upcoming election of 2018 but also the factors that influence the voting decisions of a voter. This research tries to study the relations among voters and how they view each other in general. The paper also explores the views of voters on the factors that impact decision making of a voter while casting his/her vote in Pakistan. The paper thoroughly studies the expectations of the voters from the current system that prevails in the country. The reason this research was conducted is that this kind of positive approach towards finding out the voter perception is heavily untouched in Pakistani academia. This study can benefit a lot of institutions and professions in the future too. The constraints and obstacles that came while this research was being conducted are also identified in the paper. The mode of research is primary research as it was impossible to find out the perceptions of first-time voters without going on the field and carrying out the research. The research was conducted in one of the most reputable and liberal educational institutions of Pakistan. This research is based on a survey that was conducted through questionnaires where responses were collected through a mix process of random and convenient sampling. The major findings of the study show that young voters have a realistic perspective about the electoral process in the country. The research also articulates the factors that affect the priorities of young voters, and also how young voters view other voters that belong from other sections of the society. To conclude, we can say that this research will give us a perspective that can define and identify the voter priorities of the future in Pakistan.Keywords: first time voters, general election 2018, Pakistan, young
Procedia PDF Downloads 2284847 Numerical Simulation of External Flow Around D-Shaped Cylinders
Authors: Ouldouz Nourani Zonouz, Mehdi Salmanpour
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Investigation and analysis of flow behavior around different shapes bluff bodies is one of the reputed topics for several years. The importance of these researches is about the unwanted phenomena called flow separation. The location of separation and the size of the wake region should be considered in different industrial designs. In this research a bluff body with D-shaped cross section has been analyzed. In circular cylinder flow separation point changes with Reynolds number but in D-Shaped cylinder there is fix flow separation point. So there is more wake steadiness in D-Shaped cylinder as compared to Circular cylinder and drag reduction because of wake steadiness. In the present work CFD simulation is carried out for flow past a D-Shaped cylinder to see the wake behavior. The Reynolds number regime currently studied corresponds to low Reynolds number and nominally two-dimensional wake. Also the effect of D-Shaped cylinders on the rate of heat transfer has been considered. Various results such as velocity, pressure and temperature contours and also some dimensionless numbers like drag coefficient, pressure coefficient and Nusselt number calculated for different cases.Keywords: D-shaped, CFD, external flow, low Reynolds number, square cylinder
Procedia PDF Downloads 4664846 Experimental Investigation of Heat Transfer and Scale Growth Characteristics of Crystallisation Scale in Agitation Tank
Authors: Prasanjit Das, M .M. K. Khan, M. G. Rasul, Jie Wu, I. Youn
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Crystallisation scale occurs when dissolved minerals precipitate from an aqueous solution. To investigate the crystallisation scale growth of normal solubility salt, a lab-scale agitation tank with and without baffles were used as a benchmark using potassium nitrate as the test fluid. Potassium nitrate (KNO3) solution in this test leads to crystallisation scale on heat transfer surfaces. This experimental investigation has focused on the effect of surface crystallisation of potassium nitrate on the low-temperature heat exchange surfaces on the wall of the agitation tank. The impeller agitation rate affects the scaling rate at the low-temperature agitation wall and it shows a decreasing scaling rate with an increasing agitation rate. It was observed that there was a significant variation of heat transfer coefficients and scaling resistance coefficients with different agitation rate as well as with varying impeller size, tank with and without baffles and solution concentration.Keywords: crystallisation, heat transfer coefficient, scale, resistance
Procedia PDF Downloads 1914845 Study of Strontium Sorption onto Indian Bentonite
Authors: Pankaj Pathak, Susmita Sharma
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Incessant industrial growth fulfill the energy demand of present day society, at the same time it produces huge amount of waste which could be hazardous or non-hazardous in nature. These wastes are coming out from different sources viz, nuclear power, thermal power, coal mines which contain different types of contaminants and one of the emergent contaminant is strontium, used in the present study. The isotope of strontium (Sr90) is radioactive in nature with half-life of 28.8 years and permissible limit of strontium in drinking water is 1.5 ppm. Above the permissible limit causes several types of diseases in human being. Therefore, safe disposal of strontium into ground becomes a biggest challenge for the researchers. In this context, bentonite is being used as an efficient material to retain strontium onto ground due to its specific physical, chemical and mineralogical properties which exhibits higher cation exchange capacity and specific surface area. These properties influence the interaction between strontium and bentonite, which is quantified by employing a parameter known as distribution coefficient. Batch test was conducted, and sorption isotherms were modelled at different interaction time. The pseudo first-order and pseudo second order kinetic models have been used to fit experimental data, which helps to determine the sorption rate and mechanism.Keywords: bentonite, interaction time, sorption, strontium
Procedia PDF Downloads 3104844 Association between Caries Status of First Permanent Molar with Oral Health Care Practice in Children Aged 9-12 Years in Lubuk Kilangan, Padang City
Authors: Cytha Nilam Chairani, Ditha Noviantika, Hidayati Amir, Nurul Khairiyah, Siti Rahmadita, Fadila Khairani
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Background: Dental caries is one of the most common diseases with high prevalence in children. The first permanent molar (FPM) has an essential role in establishing the occlusion. Nevertheless, FPM is very prone to caries because of various factors, such as their anatomical structure and early emergence in oral cavity. It is due to the little knowledge from parents and children regarding the timing of emergence of FPM in oral cavity which is still considered as primary teeth. Furthermore, the lack of knowledge from parents and children may affect their oral hygiene practice resulting to carious process. Objective: The aim of this study was to assess the status of FPM caries and its association with children’s oral hygiene practice in 9-12-year-old school children in Lubuk Kilangan Community Health Centre, Padang City. Methods: A cross-sectional study was performed in 50 school children (9-12 years old) using random sampling technique from two randomly selected schools in Lubuk Kilangan Community Health Centre, Padang City. A questionnaire was developed from other studies consisting of four closed ended questions regarding oral health practice. The data obtained were analyzed statistically using Mann-Whitney Test to assess the status of FPM caries and its association with children’s oral hygiene practice. Results: The results showed that 32% of children had FPMs sound and the remaining 68% had FPMs carious which were grouped into 1-2 FPMs carious (60%) and 3-4 FPMs carious (8%). The caries status of mandibular FPM (64%) was higher compared to maxillary FPM (10%). Conclusion: There was significant association in subject who did not visit dentist in the last 6 months which had more carious FPMs compared to subject who visited dentist (p < 0.05). There was no significant association between the status of FPM caries and knowledge of the timing eruption of FPM, oral hygiene instruction from parents and tooth brushing (p > 0.05).Keywords: dental caries, children, first permanent molar, oral hygiene practice
Procedia PDF Downloads 2774843 Battery State of Charge Management Algorithm for Photovoltaic Ramp Rate Control
Authors: Nam Kyu Kim, Hee Jun Cha, Jae Jin Seo, Dong Jun Won
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Output power of a photovoltaic (PV) generator depends on incident solar irradiance. If the clouds pass or the climate condition is bad, the PV output fluctuates frequently. When PV generator is connected to the grid, these fluctuations adversely affect power quality. Thus, ramp rate control with battery energy storage system (BESS) is needed to reduce PV output fluctuations. At the same time, for effective BESS operation and sizing the optimal BESS capacity, managing state of charge (SOC) is the most important part. In addition, managing SOC helps to avoid violating the SOC operating range of BESS when performing renewable integration (RI) continuously. As PV and BESS increase, the SOC management of BESS will become more important in the future. This paper presents the SOC management algorithm which helps to operate effectively BESS, and has focused on method to manage SOC while reducing PV output fluctuations. A simulation model is developed in PSCAD/EMTDC software. The simulation results show that the SOC is maintained within the operating range by adjusting the output distribution according to the SOC of the BESS.Keywords: battery energy storage system, ramp rate control, renewable integration, SOC management
Procedia PDF Downloads 1834842 The Impact on the Composition of Survey Refusals΄ Demographic Profile When Implementing Different Classifications
Authors: Eva Tsouparopoulou, Maria Symeonaki
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The internationally documented declining survey response rates of the last two decades are mainly attributed to refusals. In fieldwork, a refusal may be obtained not only from the respondent himself/herself, but from other sources on the respondent’s behalf, such as other household members, apartment building residents or administrator(s), and neighborhood residents. In this paper, we investigate how the composition of the demographic profile of survey refusals changes when different classifications are implemented and the classification issues arising from that. The analysis is based on the 2002-2018 European Social Survey (ESS) datasets for Belgium, Germany, and United Kingdom. For these three countries, the size of selected sample units coded as a type of refusal for all nine under investigation rounds was large enough to meet the purposes of the analysis. The results indicate the existence of four different possible classifications that can be implemented and the significance of choosing the one that strengthens the contrasts of the different types of respondents' demographic profiles. Since the foundation of social quantitative research lies in the triptych of definition, classification, and measurement, this study aims to identify the multiplicity of the definition of survey refusals as a methodological tool for the continually growing research on non-response.Keywords: non-response, refusals, European social survey, classification
Procedia PDF Downloads 904841 Based on MR Spectroscopy, Metabolite Ratio Analysis of MRI Images for Metastatic Lesion
Authors: Hossain A, Hossain S.
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Introduction: In a small cohort, we sought to assess the magnetic resonance spectroscopy's (MRS) ability to predict the presence of metastatic lesions. Method: A Popular Diagnostic Centre Limited enrolled patients with neuroepithelial tumors. The 1H CSI MRS of the brain allows us to detect changes in the concentration of specific metabolites caused by metastatic lesions. Among these metabolites are N-acetyl-aspartate (NNA), creatine (Cr), and choline (Cho). For Cho, NAA, Cr, and Cr₂, the metabolic ratio was calculated using the division method. Results: The NAA values were 0.63 and 5.65 for tumor cells, 1.86 and 5.66 for normal cells, and 1.86 and 5.66 for normal cells 2. NAA values for normal cells 1 were 1.84, 10.6, and 1.86 for normal cells 2, respectively. Cho levels were as low as 0.8 and 10.53 in the tumor cell, compared to 1.12 and 2.7 in the normal cell 1 and 1.24 and 6.36 in the normal cell 2. Cho/Cr₂ barely distinguished itself from the other ratios in terms of significance. For tumor cells, the ratios of Cho/NAA, Cho/Cr₂, NAA/Cho, and NAA/Cr₂ were significant. Normal cell 1 had significant Cho/NAA, Cho/Cr, NAA/Cho, and NAA/Cr ratios. Conclusion: The clinical result can be improved by using 1H-MRSI to guide the size of resection for metastatic lesions. Even though it is non-invasive and doesn't present any difficulties during the procedure, MRS has been shown to predict the detection of metastatic lesions.Keywords: metabolite ratio, MRI images, metastatic lesion, MR spectroscopy, N-acetyl-aspartate
Procedia PDF Downloads 1024840 Intestacy and Business Continuity among Entrepreneurs in Ondo State, Nigeria
Authors: Igbekoyi Olusola Esther, Olurankinse Felix
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This paper examined the factors that militate against Will writing among entrepreneurs in Ondo State Nigeria and the effect of intestate death on business continuity after the exit of the entrepreneurs. The paper was written with a view to providing information on the reasons why intestate death is common among entrepreneurs in Ondo State and the effects on continuity of business after death of the initial owners. Data were obtained from primary source through the administration of questionnaires to entrepreneurs drawn from 50 registered manufacturing companies. These companies have been in existence for a minimum of 10 years with minimum staff strength of 20 workers each. These companies were selected using the purposive random sampling technique in order to capture firms that meet the requirements of this paper. Data obtained were analyzed using descriptive statistics, chi-square and regression analysis. The findings of the paper revealed that administration of Will, traditional beliefs, Will execution procedures, age and non- admissibility of Wills in court are the major factors that militates against Will writing among entrepreneurs in Ondo State. It was also discovered that chaos and instability in business, reduction in sales and productivity, poor succession planning, polygamous nature of marriages, difficulty in sourcing for funds and gender preference are joint predictors of business continuity in event intestate death which is evident in the result where R2 =.954;(F 6, 26)= 89.644; (P < 0.01). The individual beta co-efficient, t- statistics and significance of each variable revealed that gender preference (.735; 7.031; .000) and poor succession plan (.402; 2.840; .009) have significant positive effect on business continuity; while reduction in sales and productivity (-.059; -.335; .740) and difficulty in sourcing for funds (-.217; -1.367; .188) have negative effect; other variables also have positive relationship but they are not significant. It is therefore concluded that business continuity after the exit of the entrepreneur is highly dependent on the rebuilding of confidence on Wills administration in ondo state Nigeria, proper succession planning and elimination of gender preferences.Keywords: intestacy, business continuity, entrepreneurs, will, succession planning
Procedia PDF Downloads 3344839 Exploring Sexual Behavior among Unmarried Male Youth in Bangladesh: A Cross-Sectional Study
Authors: Subas Chandra Biswas, Kazi Sameen Naser, Farzana Misha
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Little is known about the sexual behavior of male youth, particularly unmarried young men in Bangladesh as most of the sexual and reproductive health and rights-related research and intervention are mainly focused on females and married couples. To understand the unmarried youth’s sexual behavior, data from a nationwide survey conducted in all 64 districts of Bangladesh were analyzed. Using multistage systematic random sampling, a survey was conducted among 11,113 male youth aged 15-24 years from May-August, 2019. This article analyzed and presented findings of the sexual behavior of unmarried respondents based on the data collected from 10,026 unmarried male youth. Findings showed that 18% had ever experience of sexual relationship, and the reported mean age of first sexual intercourse was 16.5years. For unmarried male youth, those who had a sexual experience, their first sexual partners were female friends/classmate (57%), female neighbors (16%), and female sex workers (12%), relatives (6%) and girlfriends with whom they had love relationship (4%). However, about 36% reported that they had a love relationship with girlfriends, and among them, 23% reported that they had sexual intercourse with their girlfriend. Those who had sexual relations with their girlfriend, 47% reported that they did not use the condom in their last sex with their girlfriend. Furthermore, 29% reported that they had sexual relationships with others besides their girlfriends. Other reported partners were female sex workers (32%), neighbors (29%), female friends (19%), relatives (12%), and cousins (5%). Also, 46% reported that they did not even use the condom during sex with other partners. About 9% used some sort of sexual stimulant to increase their libido. Among the respondents, 376 reported that they bought sex in the last six months, and the mean expenditure of buying sex for the respondent was 1,140 Taka (13.46 US Dollar). Though premarital sexual relations are not socially accepted, findings showed a large portion of male youth are engaged in these relationships and risky sexual behavior. Lack of awareness of sexual and reproductive health, unprotected sexual intercourse, use of the drug during sexual intercourse also increase the threats to health. Thus these findings are important to understand the sexual behavior of male youth in policy and programmatic implications. Therefore, to ensure a healthy sexual life and wellbeing, an immediate and culturally sensitive sexual health promotion intervention is needed for male youth in Bangladesh.Keywords: Bangladesh, male youth, sexual and reproductive health, sexual behavior
Procedia PDF Downloads 1434838 Effects of Breed and Number of Embryos Transferred on the Efficacy of MOET in Sheep
Authors: Ayman A. Swelum, Abdullah N. Al-Owaimer, Mohamed A. Abouheif
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This study aimed to evaluate the effects of sheep breed and the number of embryos transferred on the success of multiple ovulation and embryo transfer (MOET). Sixteen Najdi and Naeimi ewes were used as donors. Multiple ovulation was achieved using equine chorionic gonadotropin (eCG). Thirty-five recipient ewes were divided into four groups: Najdi or Naeimi ewes that received either one or two embryos. After lambing, the gestation length, litter size, and sex of the lambs were recorded. The rates of pregnancy, lambing, and embryo survival were lower in the recipient Najdi than Naeimi ewes when two embryos were transferred. In contrast, the Naeimi ewes that received one embryo had a significantly lower embryo transfer success. In conclusion, the response of ewes to multiple ovulation stimulation using eCG was significantly high in Naeimi ewes (9.8±1.17). Moreover, transferring one embryo resulted in a significantly high pregnancy rate in the Najdi sheep (60%).Keywords: embryo transfer, multiple ovulation, Najdi, Naeimi, sheep
Procedia PDF Downloads 7324837 Screen Method of Distributed Cooperative Navigation Factors for Unmanned Aerial Vehicle Swarm
Authors: Can Zhang, Qun Li, Yonglin Lei, Zhi Zhu, Dong Guo
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Aiming at the problem of factor screen in distributed collaborative navigation of dense UAV swarm, an efficient distributed collaborative navigation factor screen method is proposed. The method considered the balance between computing load and positioning accuracy. The proposed algorithm utilized the factor graph model to implement a distributed collaborative navigation algorithm. The GNSS information of the UAV itself and the ranging information between the UAVs are used as the positioning factors. In this distributed scheme, a local factor graph is established for each UAV. The positioning factors of nodes with good geometric position distribution and small variance are selected to participate in the navigation calculation. To demonstrate and verify the proposed methods, the simulation and experiments in different scenarios are performed in this research. Simulation results show that the proposed scheme achieves a good balance between the computing load and positioning accuracy in the distributed cooperative navigation calculation of UAV swarm. This proposed algorithm has important theoretical and practical value for both industry and academic areas.Keywords: screen method, cooperative positioning system, UAV swarm, factor graph, cooperative navigation
Procedia PDF Downloads 844836 Conductivity-Depth Inversion of Large Loop Transient Electromagnetic Sounding Data over Layered Earth Models
Authors: Ravi Ande, Mousumi Hazari
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One of the common geophysical techniques for mapping subsurface geo-electrical structures, extensive hydro-geological research, and engineering and environmental geophysics applications is the use of time domain electromagnetic (TDEM)/transient electromagnetic (TEM) soundings. A large transmitter loop for energising the ground and a small receiver loop or magnetometer for recording the transient voltage or magnetic field in the air or on the surface of the earth, with the receiver at the center of the loop or at any random point inside or outside the source loop, make up a large loop TEM system. In general, one can acquire data using one of the configurations with a large loop source, namely, with the receiver at the center point of the loop (central loop method), at an arbitrary in-loop point (in-loop method), coincident with the transmitter loop (coincidence-loop method), and at an arbitrary offset loop point (offset-loop method), respectively. Because of the mathematical simplicity associated with the expressions of EM fields, as compared to the in-loop and offset-loop systems, the central loop system (for ground surveys) and coincident loop system (for ground as well as airborne surveys) have been developed and used extensively for the exploration of mineral and geothermal resources, for mapping contaminated groundwater caused by hazardous waste and thickness of permafrost layer. Because a proper analytical expression for the TEM response over the layered earth model for the large loop TEM system does not exist, the forward problem used in this inversion scheme is first formulated in the frequency domain and then it is transformed in the time domain using Fourier cosine or sine transforms. Using the EMLCLLER algorithm, the forward computation is initially carried out in the frequency domain. As a result, the EMLCLLER modified the forward calculation scheme in NLSTCI to compute frequency domain answers before converting them to the time domain using Fourier Cosine and/or Sine transforms.Keywords: time domain electromagnetic (TDEM), TEM system, geoelectrical sounding structure, Fourier cosine
Procedia PDF Downloads 964835 Corrosion Characterization of Al6061, Quartz Metal Matrix Composites in Alkali Medium
Authors: Radha H. R., Krupakara P. V.
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Metal matrix composites are attracting today's manufacturers of many automobile parts so that they lost longer and their properties can be tailored according to the requirement. In this paper an attempt has been made to study the corrosion characteristics of Aluminium 6061 / quartz metal matrix composites in alkali medium like sodium hydroxide solutions. Metal matrix composites are heterogeneous mixtures of a matrix and reinforcement. In this work the matrix selected is Aluminium 6061 alloy which is commercially available and the reinforcement selected is quartz particulates of 50-80 micron size which is available in plenty in and around Bangalore district, India. Composites containing Aluminium 6061 with 2, 4 and 6 weight percent of quartz are manufactured by liquid melt metallurgy technique using vortex method. Corrosion tests like static weight loss and open circuit potential tests are conducted in different concentrated solutions of sodium hydroxide. To compare the results the matrix Aluminium 6061 is also casted in the same way. Specimens for the test are prepared according to ASTM standards. In all the tests the metal matrix composites showed better corrosion resistance than matrix alloy.Keywords: aluminium 6061, corrosion, quartz, vortex
Procedia PDF Downloads 4134834 Integrated Vegetable Production Planning Considering Crop Rotation Rules Using a Mathematical Mixed Integer Programming Model
Authors: Mohammadali Abedini Sanigy, Jiangang Fei
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In this paper, a mathematical optimization model was developed to maximize the profit in a vegetable production planning problem. It serves as a decision support system that assists farmers in land allocation to crops and harvest scheduling decisions. The developed model can handle different rotation rules in two consecutive cycles of production, which is a common practice in organic production system. Moreover, different production methods of the same crop were considered in the model formulation. The main strength of the model is that it is not restricted to predetermined production periods, which makes the planning more flexible. The model is classified as a mixed integer programming (MIP) model and formulated in PYOMO -a Python package to formulate optimization models- and solved via Gurobi and CPLEX optimizer packages. The model was tested with secondary data from 'Australian vegetable growing farms', and the results were obtained and discussed with the computational test runs. The results show that the model can successfully provide reliable solutions for real size problems.Keywords: crop rotation, harvesting, mathematical model formulation, vegetable production
Procedia PDF Downloads 1934833 Energy-Efficient Contact Selection Method for CARD in Wireless Ad-Hoc Networks
Authors: Mehdi Assefi, Keihan Hataminezhad
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One of the efficient architectures for exploring the resources in wireless ad-hoc networks is contact-based architecture. In this architecture, each node assigns a unique zone for itself and each node keeps all information from inside the zone, as well as some from outside the zone, which is called contact. Reducing the overlap between different zones of a node and its contacts increases its performance, therefore Edge Method (EM) is designed for this purpose. Contacts selected by EM do not have any overlap with their sources, but for choosing the contact a vast amount of information must be transmitted. In this article, we will offer a new protocol for contact selection, which is called PEM. The objective would be reducing the volume of transmitted information, using Non-Uniform Dissemination Probabilistic Protocols. Consumed energy for contact selection is a function of the size of transmitted information between nodes. Therefore, by reducing the content of contact selection message using the PEM will decrease the consumed energy. For evaluation of the PEM we applied the simulation method. Results indicated that PEM consumes less energy compared to EM, and by increasing the number of nodes (level of nodes), performance of PEM will improve in comparison with EM.Keywords: wireless ad-hoc networks, contact selection, method for CARD, energy-efficient
Procedia PDF Downloads 2944832 The Effects of Siltation in Seagrass along Claver Surigao Del Norte
Authors: Dawn Rosarie M. Fajardo
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Seagrass plays a crucial role in sustaining marine ecosystem. In this investigation two areas (Panyug and Kinalablaban) were studied to assess the effect of siltation in seagrass condition. The size of the sediment was also examined. Data analysis showed that Panyug had higher level of silt compared to Kinalablaban. The results indicate that seagrass is vulnerable to environmental disturbances. The results also indicate that plants grown in undisturbed natural sediments were more successful than plants in sediments which were disturbed. In addition to that, there are total of seven species of seagrass that are found tolerant with siltation it includes Enhalus acoroides, Cymodocea rotundata, Halophila minor, Halodule pinifolia, Halodule uninervis, Syringodium isoetifolium, and Thalassia hemprichii. The results were given emphasis especially for the five representative quadrats in each area. Among these species of seagrass Cymodocea rotundata is the most tolerant to siltation. There is also no significant relationships between silt and seagrass percent cover which had r² = 0.192, Panyug and r² = 0.145, at Kinalablaban at P> 0.05. The data showed that Panyug (area 1) was characterized with high level of silt compared to that of Kinalablaban that contains more granulated sediments.Keywords: seagrass, siltation, cymodocea rotundata, sediments, environmental issues
Procedia PDF Downloads 5334831 TiO2 Adsorbed on Cement Balls for Effective Photomineralization of Organic Pollutants under UV Light Irradiation
Authors: Tarun Jain, Lovnish Gupta, Soumen Basu
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Organic pollutants like phenols and organic dyes present in industrial waste water are posing a hazardous threat to aquatic ecosystem. Several measures have been adopted for the neutralization and photodecomposition of these harmful organic moieties, among these semiconductor photocatalysis has been provided a major thrust after the discovery of Honda-Fujishema effect. Present study demonstrates the adsorption of TiO2- P25 in nano size (~36 nm) on cement balls for effective photodegradation of Alizarin and penta chlorophenol (PCP) under UV light illumination. Triton-X was used as a stabilizer for effective adsorption of TiO2 on cement balls (TCB) followed by calcination at ~300oC for 4 h. The TCB’s were dispersed randomly in a self designed reactor for phototcatalytic performance as shown in scheme 1. The change in concentration of alizarin and PCP was observed under UV-Vis spectroscopy, PCP was detoxified within 40 min while alizarin photodecomposed within 15 min of UV light irradiation. Taking into consideration the go green slogan and future prospective this technique can be also utilized under visible light and on mass scale because this is an effective tool for environmental remediation and waste water treatment.Keywords: organic pollutants, TiO2 cement balls, photodegradation, UV light irradiation
Procedia PDF Downloads 267