Search results for: chaotic differential evolution (CDDE)
936 DOG1 Expression Is in Common Human Tumors: A Tissue Microarray Study on More than 15,000 Tissue Samples
Authors: Kristina Jansen, Maximilian Lennartz, Patrick Lebok, Guido Sauter, Ronald Simon, David Dum, Stefan Steurer
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DOG1 (Discovered on GIST1) is a voltage-gated calcium-activated chloride and bicarbonate channel that is highly expressed in interstitial cells of Cajal and in gastrointestinal stromal tumors (GIST) derived from Cajal cells. To systematically determine in what tumor entities and normal tissue types DOG1 may be further expressed, a tissue microarray (TMA) containing 15,965 samples from 121 different tumor types and subtypes as well as 608 samples of 76 different normal tissue types were analyzed by immunohistochemistry. DOG1 immunostaining was found in 67 tumor types, including GIST (95.7%), esophageal squamous cell carcinoma (31.9%), pancreatic ductal adenocarcinoma (33.6%), adenocarcinoma of the Papilla Vateri (20%), squamous cell carcinoma of the vulva (15.8%) and the oral cavity (15.3%), mucinous ovarian cancer (15.3%), esophageal adenocarcinoma (12.5%), endometrioid endometrial cancer (12.1%), neuroendocrine carcinoma of the colon (11.1%) and diffuse gastric adenocarcinoma (11%). Low level-DOG1 immunostaining was seen in 17 additional tumor entities. DOG1 expression was unrelated to histopathological parameters of tumor aggressiveness and/or patient prognosis in cancers of the breast (n=1,002), urinary bladder (975), ovary (469), endometrium (173), stomach (233), and thyroid gland (512). High DOG1 expression was linked to estrogen receptor expression in breast cancer (p<0.0001) and the absence of HPV infection in squamous cell carcinomas (p=0.0008). In conclusion, our data identify several tumor entities that can show DOG1 expression levels at similar levels as in GIST. Although DOG1 is tightly linked to a diagnosis of GIST in spindle cell tumors, the differential diagnosis is much broader in DOG1 positive epithelioid neoplasms.Keywords: biomarker, DOG1, immunohistochemistry, tissue microarray
Procedia PDF Downloads 216935 The Differentiation of Performances among Immigrant Entrepreneurs: A Biographical Approach
Authors: Daniela Gnarini
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This paper aims to contribute to the field of immigrants' entrepreneurial performance. The debate on immigrant entrepreneurship has been dominated by cultural explanations, which argue that immigrants’ entrepreneurial results are linked to groups’ characteristics. However, this approach does not consider important dimensions that influence entrepreneurial performances. Furthermore, cultural theories do not take into account the huge differences in performances also within the same ethnic group. For these reason, this study adopts a biographical approach, both at theoretical and at methodological level, which can allow to understand the main aspects that make the difference in immigrants' entrepreneurial performances, by exploring the narratives of immigrant entrepreneurs, who operate in the restaurant sector in two different Italian metropolitan areas: Milan and Rome. Through the qualitative method of biographical interviews, this study analyses four main dimensions and their combinations: a) individuals' entrepreneurial and migratory path: this aspect is particularly relevant to understand the biographical resources of immigrant entrepreneurs and their change and evolution during time; b) entrepreneurs' social capital, with a particular focus on their networks, through the adoption of a transnational perspective, that takes into account both the local level and the transnational connections. This study highlights that, though entrepreneurs’ connections are significant, especially as far as those with family members are concerned, often their entrepreneurial path assumes an individualised trajectory. c) Entrepreneurs' human capital, including both formal education and skills acquired through informal channels. The latter are particularly relevant since in the interviews and data collected the role of informal transmission emerges. d) Embeddedness within the social, political and economic context, to understand the main constraints and opportunities both at local and national level. The comparison between two different metropolitan areas within the same country helps to understand this dimension.Keywords: biographies, immigrant entrepreneurs, life stories, performance
Procedia PDF Downloads 226934 Microstructural Evolution of Maraging Steels from Powder Particles to Additively Manufactured Samples
Authors: Seyedamirreza Shamsdini, Mohsen Mohammadi
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In this research, 18Ni-300 maraging steel powder particles are investigated by studying particle size distribution along with their morphology and grain structure. The powder analysis shows mostly spherical morphologies with cellular structures. A laser-based additive manufacturing process, selective laser melting (SLM) is used to produce samples for further investigation of mechanical properties and microstructure. Several uniaxial tensile tests are performed on the as-built parts to evaluate the mechanical properties. The macroscopic properties, as well as microscopic studies, are then investigated on the printed parts. Hardness measurements, as well as porosity levels, are measured for each sample and are correlated with microstructures through electron microscopy techniques such as Scanning Electron Microscopy (SEM) and Transmission Electron Microscopy (TEM). The grain structure is studied for the as-printed specimens and compared to the powder particle microstructure. The cellular structure of the printed samples is observed to have dendritic forms with dendrite width dimensions similar to the powder particle cells. The process parameter is changed, and the study is performed for different powder layer thickness, and the resultant mechanical properties and grain structure are shown to be similar. A phase study is conducted both on the powder and the printed samples using X-Ray Diffraction (XRD) techniques, and the austenite phase is observed to at first decrease due to the manufacturing process and again during the uniaxial tensile deformation. The martensitic structure is formed in the first stage based on the heating cycles of the manufacturing process and the remaining austenite is shown to be transformed to martensite due to different deformation mechanisms.Keywords: additive manufacturing, maraging steel, mechanical properties, microstructure
Procedia PDF Downloads 159933 Spatial Interpolation of Intermediate Soil Properties to Enhance Geotechnical Surveying for Foundation Design
Authors: Yelbek B. Utepov, Assel T. Mukhamejanova, Aliya K. Aldungarova, Aida G. Nazarova, Sabit A. Karaulov, Nurgul T. Alibekova, Aigul K. Kozhas, Dias Kazhimkanuly, Akmaral K. Tleubayeva
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This research focuses on enhancing geotechnical surveying for foundation design through the spatial interpolation of intermediate soil properties. Traditional geotechnical practices rely on discrete data from borehole drilling, soil sampling, and laboratory analyses, often neglecting the continuous nature of soil properties and disregarding values in intermediate locations. This study challenges these omissions by emphasizing interpolation techniques such as Kriging, Inverse Distance Weighting, and Spline interpolation to capture the nuanced spatial variations in soil properties. The methodology is applied to geotechnical survey data from two construction sites in Astana, Kazakhstan, revealing continuous representations of Young's Modulus, Cohesion, and Friction Angle. The spatial heatmaps generated through interpolation offered valuable insights into the subsurface environment, highlighting heterogeneity and aiding in more informed foundation design decisions for considered cites. Moreover, intriguing patterns of heterogeneity, as well as visual clusters and transitions between soil classes, were explored within seemingly uniform layers. The study bridges the gap between discrete borehole samples and the continuous subsurface, contributing to the evolution of geotechnical engineering practices. The proposed approach, utilizing open-source software geographic information systems, provides a practical tool for visualizing soil characteristics and may pave the way for future advancements in geotechnical surveying and foundation design.Keywords: soil mechanical properties, spatial interpolation, inverse distance weighting, heatmaps
Procedia PDF Downloads 85932 Changing Geomorphosites in a Changing Lake: How Environmental Changes in Urmia Lake Have Been Driving Vanishing or Creating of Geomorphosites
Authors: D. Mokhtari
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Any variation in environmental characteristics of geomorphosites would lead to destabilisation of their geotouristic values all around the planet. The Urmia lake, with an area of approximately 5,500 km2 and a catchment area of 51,876 km2, and to which various reasons over time, especially in the last fifty years have seen a sharp decline and have decreased by about 93 % in two recent decades. These variations are not only driving significant changes in the morphology and ecology of the present lake landscape, but at the same time are shaping newly formed morphologies, which vanished some valuable geomorphosites or develop into smaller geomorphosites with significant value from a scientific and cultural point of view. This paper analyses and discusses features and evolution in several representative coastal and island geomorphosites. For this purpose, a total of 23 geomorphosites were studied in two data series (1963 and 2015) and the respective data were compared and analysed. The results showed, The total loss in geomorphosites area in a half century amounted to a loss of more than 90% of the valuable geomorphosites. Moreover, the comparison between the mean yearly value of coastal area lost over the entire period and the yearly average calculated for the shorter period (1998-2014) clearly indicates a pattern of acceleration. This acceleration in the rate of reduction in lake area was seen in most of the southern half of the lake. In the region as well, the general water-level falling is not only causing the loss of a significant water resource, which is followed by major impact on regional ecosystems, but is also driving the most marked recent (last century) changes in the geotouristic landscapes. In fact, the disappearance of geomorphosites means the loss of tourism phenomenon. In this context attention must be paid to the question of conservation. The action needed to safeguard geomorphosites includes: 1) Preventive action, 2) Corrective action, and 3) Sharing knowledge.Keywords: geomorphosite, environmental changes, changing lake, Urmia lake, northwest of Iran
Procedia PDF Downloads 378931 In Stemming Out Societal Depravity: Existentialism, Realism, and Contrapuntal Criticism in Nigerian Arabic Poetry: Ibn Yusuf’s Anthology as Paradigm
Authors: Izzudeen Adetunji
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The intrinsic nexus between man and society is apparently unknown to many people despite understanding the real responsibility and immense roles in society. Amongst the in-depth roles of a man as an agent of the societal reformer is to be a driven force towards installing normalcy and socio-cultural change in society. The paradoxical attitudes of man in engaging in social vices, illicit characters, and unwanted attitudes have given birth to decay and ill-society. However, the need for social change or socio-cultural evolution might be necessary to install normalcy and social order. Nigerian Arabic poets since the 19th century have tremendously engaged in utilizing their poetry for social change through socio-cultural, religious, economic, scientific, or technological forces. This engagement has hitherto yielded a positive outcome for societal reform. The anthology of Ibn Yusuf is one of the compendiums of poetries revealing societal depravity, man’s social vices, and atrocities; which later called to flawlessness. The theoretical framework would be examined through the Heraclitan model, focusing on a parallel to that of a living organism, which, in order to remain alive, must constantly change. Therefore, the thrust of this paper is to examine the societal maladies as elucidated in Ibn Yusuf’s anthology and proffer a contrapuntal criticism of it. Before delving into the main discussion, the paper will examine the concepts of existentialism and realism as a philosophical interface. Likewise, the issues of man and social change, an overview of Nigerian Arabic poetry, will be discussed. Ibn Yusuf’s biography and scholarship and the review of his anthology will be studied. The paper will conclude by critically examining the contrapuntal criticism of societal maladies through Ibn Yusuf’s anthology.Keywords: societal depravity, existentialism, realism, Nigeria Arabic poetry, Ibn Yusuf’s anthology, contrapuntal criticism
Procedia PDF Downloads 25930 Protein Feeding Pattern, Casein Feeding, or Milk-Soluble Protein Feeding did not Change the Evolution of Body Composition during a Short-Term Weight Loss Program
Authors: Solange Adechian, Michèle Balage, Didier Remond, Carole Migné, Annie Quignard-Boulangé, Agnès Marset-Baglieri, Sylvie Rousset, Yves Boirie, Claire Gaudichon, Dominique Dardevet, Laurent Mosoni
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Studies have shown that timing of protein intake, leucine content, and speed of digestion significantly affect postprandial protein utilization. Our aim was to determine if one can spare lean body mass during energy restriction by varying the quality and the timing of protein intake. Obese volunteers followed a 6-wk restricted energy diet. Four groups were compared: casein pulse, casein spread, milk-soluble protein (MSP, = whey) pulse, and MSP spread (n = 10-11 per group). In casein groups, caseins were the only protein source; it was MSP in MSP groups. Proteins were distributed in four meals per day in the proportion 8:80:4:8% in the pulse groups; it was 25:25:25:25% in the spread groups. We measured weight, body composition, nitrogen balance, 3-methylhistidine excretion, perception of hunger, plasma parameters, adipose tissue metabolism, and whole body protein metabolism. Volunteers lost 7.5 ± 0.4 kg of weight, 5.1 ± 0.2 kg of fat, and 2.2 ± 0.2 kg of lean mass, with no difference between groups. In adipose tissue, cell size and mRNA expression of various genes were reduced with no difference between groups. Hunger perception was also never different between groups. In the last week, due to a higher inhibition of protein degradation and despite a lower stimulation of protein synthesis, postprandial balance between whole body protein synthesis and degradation was better with caseins than with MSP. It seems likely that the positive effect of caseins on protein balance occurred only at the end of the experiment.Keywords: lean body mass, fat mass, casein, whey, protein metabolism
Procedia PDF Downloads 72929 When Your Change The Business Model ~ You Change The World
Authors: H. E. Amb. Terry Earthwind Nichols
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Over the years Ambassador Nichols observed that successful companies all have one thing in common - belief in people. His observations of people in many companies, industries, and countries have also concluded one thing - groups of achievers far exceed the expectations and timelines of their superiors. His experience with achieving this has brought forth a model for the 21st century that will not only exceed expectations of companies, but it will also set visions for the future of business globally. It is time for real discussion around the future of work and the business model that will set the example for the world. Methodologies: In-person observations over 40 years – Ambassador Nichols present during the observations. Audio-visual observations – TV, Cinema, social media (YouTube, etc.), various news outlet Reading the autobiography of some of successful leaders over the last 75 years that lead their companies from a distinct perspective your people are your commodity. Major findings: People who believe in the leader’s vision for the company so much so that they remain excited about the future of the company and want to do anything in their power to ethically achieve that vision. People who are achieving regularly in groups, division, companies, etcetera: Live more healthfully lowering both sick time off and on-the-job accidents. Cannot wait to physically get to work as much as they can to feed off the high energy present in these companies. They are fully respected and supported resulting in near zero attrition. Simply put – they do not “Burn Out”. Conclusion: To the author’s best knowledge, 20th century practices in business are no longer valid and people are not going to work in those environments any longer. The average worker in the post-covid world is better educated than 50 years ago and most importantly, they have real-time information about any subject and can stream injustices as they happen. The Consortium Model is just the model for the evolution of both humankind and business in the 21st century.Keywords: business model, future of work, people, paradigm shift, business management
Procedia PDF Downloads 78928 Factors Affecting Entrepreneurial Behavior and Performance of Youth Entrepreneurs in Malaysia
Authors: Mohd Najib Mansor, Nur Syamilah Md. Noor, Abdul Rahim Anuar, Shazida Jan Mohd Khan, Ahmad Zubir Ibrahim, Badariah Hj Din, Abu Sufian Abu Bakar, Kalsom Kayat, Wan Nurmahfuzah Jannah Wan Mansor
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This study aimed and focused on the behavior of youth entrepreneurs’ especially entrepreneurial self-efficacy and the performance in micro SMEs in Malaysia. Entrepreneurship development calls for support from various quarters, and mostly the need exists to initiate a youth entrepreneurship culture and drive amongst the youth in the society. Although backed up by the government and non-government organizations, micro-entrepreneurs are still facing challenges which greatly delay their progress, growth and consequently their input towards economic advancement. Micro-entrepreneurs are confronted with unique difficulties such as uncertainty, innovation, and evolution. Reviews on the development of entrepreneurial characteristics such as need for achievement, internal locus of control, risk-taking and innovation and have been recognized as highly associated with entrepreneurial behavior. The data in this study was obtained from the Department of Statistics, Malaysia. A random sampling of 830 respondents was distributed to 14 states that involve of micro-entrepreneurs. The study adopted a quantitative approach whereby a set of questionnaire was used to gather data. Multiple regression analysis was chosen as a method of analysis testing. The result of this study is expected to provide insight into the factor affecting entrepreneurial behavior and performance of youth entrepreneurs in micro SMEs. The finding showed that the Malaysian youth entrepreneurs do not have the entrepreneurial self-efficacy within themselves in order to accomplish greater success in their business venture. The establishment of entrepreneurial schools to allow our youth to be exposed to entrepreneurship from an early age and the development of special training focuses on the creation of business network so that the continuous entrepreneurial culture is crafted.Keywords: youth entrepreneurs, micro entrepreneurs, entrepreneurial self-efficacy, entrepreneurial performance
Procedia PDF Downloads 302927 Women Doing Leadership in Higher Education: Drawing on Individual Experiences to Analyse On-Going Gender Inequality in the Sector
Authors: Sarah Barnard, John Arnold, Fehmidah Munir, Sara Bosley
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Gender issues in higher education continue to represent a complex issue as institutions grapple with the role that organisations can play in combatting inequality. Schemes like Athena SWAN and the Aurora leadership programme in the UK context are attempting to tackle some of the issues around representation and the recognition of women in the sector. This paper is the first of its kind in reporting findings from a mixed-methods longitudinal study on both professional services and academic women in higher education in the UK. Online surveys have been completed by over 2,000 women in the sector. The qualitative elements include interviews with women and their mentors, and diaries with a select group of women. So far results have shown that contrary to the stereotype of women lacking leadership skills or having no desire to go into higher roles, women in the sector consistently assessed their leadership abilities positively, especially but not only regarding interpersonal interaction and facilitation. Over 80% of women agreed that they felt confident about putting themselves forward for positions of responsibility at work. However, qualitative data shows that confidence remains a salient term for how women talk about the challenges they have faced at work. This suggests that the work needed to challenge systemic gender issues requires action to be driven above the individual level. Overall, academics reported more negative experiences than professional services staff. Similarly BAME women’s responses are more negative. Therefore, the study offers some information on the differential experiences of women. In conclusion, women in higher education are undertaking considerable ‘below the radar’ leadership activities in what they perceive to be a somewhat inhospitable hostile workplace culture. The significant amount of effort expended in the sector is affecting slow, partial impacts on gender inequalities.Keywords: gender, higher education, leadership, longitudinal research
Procedia PDF Downloads 244926 Dual Metal Organic Framework Derived N-Doped Fe3C Nanocages Decorated with Ultrathin ZnIn2S4 Nanosheets for Efficient Photocatalytic Hydrogen Generation
Authors: D. Amaranatha Reddy
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Highly efficient and stable co-catalysts materials is of great important for boosting photo charge carrier’s separation, transportation efficiency, and accelerating the catalytic reactive sites of semiconductor photocatalysts. As a result, it is of decisive importance to fabricate low price noble metal free co-catalysts with high catalytic reactivity, but it remains very challenging. Considering this challenge here, dual metal organic frame work derived N-Doped Fe3C nanocages have been rationally designed and decorated with ultrathin ZnIn2S4 nanosheets for efficient photocatalytic hydrogen generation. The fabrication strategy precisely integrates co-catalyst nanocages with ultrathin two-dimensional (2D) semiconductor nanosheets by providing tightly interconnected nano-junctions and helps to suppress the charge carrier’s recombination rate. Furthermore, constructed highly porous hybrid structures expose ample active sites for catalytic reduction reactions and harvest visible light more effectively by light scattering. As a result, fabricated nanostructures exhibit superior solar driven hydrogen evolution rate (9600 µmol/g/h) with an apparent quantum efficiency of 3.6 %, which is relatively higher than the Pt noble metal co-catalyst systems and earlier reported ZnIn2S4 based nanohybrids. We believe that the present work promotes the application of sulfide based nanostructures in solar driven hydrogen production.Keywords: photocatalysis, water splitting, hydrogen fuel production, solar-driven hydrogen
Procedia PDF Downloads 133925 Experimental Study and Numerical Simulation of the Reaction and Flow on the Membrane Wall of Entrained Flow Gasifier
Authors: Jianliang Xu, Zhenghua Dai, Zhongjie Shen, Haifeng Liu, Fuchen Wang
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In an entrained flow gasifier, the combustible components are converted into the gas phase, and the mineral content is converted into ash. Most of the ash particles or droplets are deposited on the refractory or membrane wall and form a slag layer that flows down to the quenching system. The captured particle reaction process and slag flow and phase transformation play an important role in gasifier performance and safe and stable operation. The reaction characteristic of captured char particles on the molten slag had been studied by applied a high-temperature stage microscope. The gasification process of captured chars with CO2 on the slag surface was observed and recorded, compared to the original char gasification. The particle size evolution, heat transfer process are discussed, and the gasification reaction index of the capture char particle are modeled. Molten slag layer promoted the char reactivity from the analysis of reaction index, Coupled with heat transfer analysis, shrinking particle model (SPM) was applied and modified to predict the gasification time at carbon conversion of 0.9, and results showed an agreement with the experimental data. A comprehensive model with gas-particle-slag flow and reaction models was used to model the different industry gasifier. The carbon conversion information in the spatial space and slag layer surface are investigated. The slag flow characteristic, such as slag velocity, molten slag thickness, slag temperature distribution on the membrane wall and refractory brick are discussed.Keywords: char, slag, numerical simulation, gasification, wall reaction, membrane wall
Procedia PDF Downloads 307924 Application of Environmental Justice Concept in Urban Planning, The Peri-Urban Environment of Tehran as the Case Study
Authors: Zahra Khodaee
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Environmental Justice (EJ) concept consists of multifaceted movements, community struggles, and discourses in contemporary societies that seek to reduce environmental risks, increase environmental protections, and generally reduce environmental inequalities suffered by minority and poor communities; a term that incorporates ‘environmental racism’ and ‘environmental classism,’ captures the idea that different racial and socioeconomic groups experience differential access to environmental quality. This article explores environmental justice as an urban phenomenon in urban planning and applies it in peri-urban environment of a metropolis. Tehran peri-urban environments which are the result of meeting the city- village- nature systems or «city-village junction» have gradually faced effects such as accelerated environmental decline, changes without land-use plan, and severe service deficiencies. These problems are instances of environmental injustice which make the planners to adjust the problems and use and apply the appropriate strategies and policies by looking for solutions and resorting to theories, techniques and methods related to environmental justice. In order to access to this goal, try to define environmental justice through justice and determining environmental justice indices to analysis environmental injustice in case study. Then, make an effort to introduce some criteria to select case study in two micro and micro levels. Qiyamdasht town as the peri-urban environment of Tehran metropolis is chosen and examined to show the existence of environmental injustice by questionnaire analysis and SPSS software. Finally, use AIDA technique to design a strategic plan and reduce environmental injustice in case study by introducing the better scenario to be used in policy and decision making areas.Keywords: environmental justice, metropolis of Tehran, Qiyam, Dasht peri, urban settlement, analysis of interconnected decision area (AIDA)
Procedia PDF Downloads 490923 Hypotonia - A Concerning Issue in Neonatal Care
Authors: Eda Jazexhiu-Postoli, Gladiola Hoxha, Ada Simeoni, Sonila Biba
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Background Neonatal hypotonia represents a commonly encountered issue in the Neonatal Intensive Care Unit and newborn nursery. The differential diagnosis is broad, encompassing chromosome abnormalities, primary muscular dystrophies, neuropathies and inborn errors of metabolism. Aim of study Our study describes some of the main clinical features of hypotonia in newborns and presents clinical cases of neonatal hypotonia we treated in our Neonatal unit in the last 3 years. Case reports Four neonates born in our hospital presented with hypotonia after birth, one preterm newborn 35-36 weeks of gestational age and three other term newborns (38-39 weeks of gestational age). Prenatal data revealed a decrease in fetal movements in both cases. Intrapartum meconium-stained amniotic fluid was found in 75% of our hypotonic newborns. Clinical features included inability to establish effective respiratory movements and need for resuscitation in the delivery room, respiratory distress syndrome, feeding difficulties and need for oro-gastric tube feeding, dysmorphic features, hoarse voice and moderate to severe muscular hypotonia. The genetic workup revealed the diagnosis of Autosomal Recessive Congenital Myasthenic Syndrome 1-B, Sotos Syndrome, Spinal Muscular Atrophy Type 1 and Transient Hypotonia of the Newborn. Two out of four hypotonic neonates were transferred to the Pediatric Intensive Care Unit and died at the age of three to five months old. Conclusion Hypotonia is a concerning finding in neonatal care and it is suggested by decreased intrauterine fetal movements, failure to establish first breaths, respiratory distress and feeding difficulties in the neonate. Prognosis is determined by its etiology and time of diagnosis and intervention.Keywords: hypotonic neonate, respiratory distress, feeding difficulties, fetal movements
Procedia PDF Downloads 115922 Fabrication of Coatable Polarizer by Guest-Host System for Flexible Display Applications
Authors: Rui He, Seung-Eun Baik, Min-Jae Lee, Myong-Hoon Lee
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The polarizer is one of the most essential optical elements in LCDs. Currently, the most widely used polarizers for LCD is the derivatives of the H-sheet polarizer. There is a need for coatable polarizers which are much thinner and more stable than H-sheet polarizers. One possible approach to obtain thin, stable, and coatable polarizers is based on the use of highly ordered guest-host system. In our research, we aimed to fabricate coatable polarizer based on highly ordered liquid crystalline monomer and dichroic dye ‘guest-host’ system, in which the anisotropic absorption of light could be achieved by aligning a dichroic dye (guest) in the cooperative motion of the ordered liquid crystal (host) molecules. Firstly, we designed and synthesized a new reactive liquid crystalline monomer containing polymerizable acrylate groups as the ‘host’ material. The structure was confirmed by 1H-NMR and IR spectroscopy. The liquid crystalline behavior was studied by differential scanning calorimetry (DSC) and polarized optical microscopy (POM). It was confirmed that the monomers possess highly ordered smectic phase at relatively low temperature. Then, the photocurable ‘guest-host’ system was prepared by mixing the liquid crystalline monomer, dichroic dye and photoinitiator. Coatable polarizers were fabricated by spin-coating above mixture on a substrate with alignment layer. The in-situ photopolymerization was carried out at room temperature by irradiating UV light, resulting in the formation of crosslinked structure that stabilized the aligned dichroic dye molecules. Finally, the dichroic ratio (DR), order parameter (S) and polarization efficiency (PE) were determined by polarized UV/Vis spectroscopy. We prepared the coatable polarizers by using different type of dichroic dyes to meet the requirement of display application. The results reveal that the coatable polarizers at a thickness of 8μm exhibited DR=12~17 and relatively high PE (>96%) with the highest PE=99.3%, which possess potential for the LCD or flexible display applications.Keywords: coatable polarizer, display, guest-host, liquid crystal
Procedia PDF Downloads 251921 SUMOylation Enhances Nurr1/1a Mediated Transactivation in a Neuronal Cell Type
Authors: Jade Edey, Andrew Bennett, Gareth Hathway
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Nuclear receptor-related 1 protein (also known as Nurr1 or NR4A2) is an orphan nuclear receptor which plays a vital role in the development, survival and maintenance of dopaminergic (DA) neurons particularly in the substantia nigra (SN). Increasing research has investigated Nurr1’s additional role within microglia and astrocytes where it has been suggested to act as a negative regulator of inflammation; potentially offering neuroprotection. Considering both DA neurodegeneration and neuroinflammation are commonly accepted constituents of Parkinson’s Disease (PD), understanding the mechanisms by which Nurr1 regulates inflammatory processes could provide an attractive therapeutic target. Nurr1 regulates inflammation via a transrepressive mechanism possibly dependent upon SUMOylation. In addition, Nurr1 can transactivate numerous genes involved in DA synthesis, such as Tyrosine Hydroxylase (TH). A C-terminal splice variant of Nurr1, Nurr-1a, has been reported in both neuronal and glial cells. However, research into its transcriptional activity is minimal. We employed in vitro methods such as SUMO-Pulldown experiments alongside Luciferase reporter assays to investigate the SUMOylation status and transactivation capabilities of Nurr1 and Nurr-1a respectively. The SUMO-Pulldown assay demonstrated Nurr-1a undergoes significantly more SUMO modification than its full-length variant. Consequently, despite having less transcriptional activation than Nurr1, Nurr1a may play a more prominent role in repression of microglial inflammation. Contrary to published literature we also identified that SUMOylation enhances transcriptional activation by Nurr1 and Nurr1a. SUMOylation-dependent increases in Nurr1 and Nurr1a transcriptional activation were only evident in neuronal SHSY5Y cells but not in HEK293 cells. This research provides novel insight into the regulation of Nurr-1a and indicates differential effects of SUMOylation dependent regulation in neuronal and inflammatory cells.Keywords: nuclear receptors, Parkinson’s disease, inflammation, transcriptional regulation
Procedia PDF Downloads 154920 Relationship between Cinema and Culture: Reel and Real life in India
Authors: Prachi Chavda
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The world, as of today, is smaller than it was for those who lived few decades ago. Internet, media and telecommunications have impacted the world like never before. Culture is the pillar upon which a society mushrooms. A culture develops with human creativity over the years and also by the exchange and intermixing of ideas and way of life across different civilizations and we can say that one of the influencing medium of exchange and intermixing of these ideas is cinema. Cinema has been the wonderful as well as important medium of communication since it has been emerged. Change is the thumb rule of life and so have been Indian cinema. As society has evolved from time to time so has the stories of Indian Cinema and its characters, hence it directly effects to the Indian culture as cinema has been very strong mediator for information exchange. The paper tries to discuss deeply how Indian cinema (reel life) and Indian culture (real life) has been influencing each other that results into a constant modification in both. Moreover, the research tries to deal with the issue with some examples that as a outcome how movies impact the Indian culture positively and negatively on culture. Therefore, it spreads the wave of change in cultural settings of society. The paper also tries to light the psychology of youth of India. Today, children and youth greatly admire the ostentatious materialistic display of outfits and style of the actors in the movies. Also, the movies bearing romanticism and showcasing disputatious issues like pre-marital sex, live-in relationship, homo-sexuality etc. though without highlighting them extensively have indeed inspired the commoners. Pros and cons always exist. Such revelation of issues certainly give a spark in the minds of those who are in their formative years and the effect of which is seen with the passage of time Thus, we can say that emergence of cinema as a strong tool of social change as well as culture as a triggering factor for transformation in cinema. As, a finding we can say that culture and cinema of India are influencing factors for each other. Cinema and culture are two sides of a coin, where both are responsible for evolution of each other.Keywords: cinema, culture, influence, transformation
Procedia PDF Downloads 396919 The Structure of Southern Tunisian Atlas Deformation Front: Integrated Geological and Geophysical Interpretation
Authors: D. Manai, J. Alvarez-Marron, M. Inoubli
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The southern Tunisian Atlas is a part of the wide Cenozoic intracontinental deformation that affected North Africa as a result of convergence between African and Eurasian plates. The Southern Tunisian Atlas Front (STAF) corresponds to the chotts area that covers several hundreds of Km² and represents a 60 km wide transition between the deformed Tunisian Atlas to the North and the undeformed Saharan platform to the South. It includes three morphostructural alignments, a fold and thrust range in the North, a wide depression in the middle and a monocline to horizontal zone to the south. Four cross-sections have been constructed across the chotts area to illustrate the structure of the Southern Tunisian Atlas Front based on integrated geological and geophysical data including geological maps, petroleum wells, and seismic data. The fold and thrust zone of the northern chotts is interpreted as related to a detachment level near the Triassic-Jurassic contact. The displacement of the basal thrust seems to die out progressively under the Fejej antiform and it is responsible to the south dipping of the southern chotts range. The restoration of the cross-sections indicates that the Southern Tunisian Atlas front is a weakly deformed wide zone developed during the Cenozoic inversion with a maximum calculated shortening in the order of 1000 m. The wide structure of this STAF has been influenced by a pre-existing large thickness of upper Jurassic-Aptian sediments related to the rifting episodes associated to the evolution of Tethys in the Maghreb. During Jurassic to Aptian period, the chotts area corresponded to a highly subsiding basin.Keywords: Southern Tunisian Atlas Front, subsident sub- basin, wide deformation, balanced cross-sections.
Procedia PDF Downloads 149918 The Culex Pipiens Niche: Assessment with Climatic and Physiographic Variables via a Geographic Information System
Authors: Maria C. Proença, Maria T. Rebelo, Marília Antunes, Maria J. Alves, Hugo Osório, Sofia Cunha, João Casaca
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Using a geographic information system (GIS), the relations between a georeferenced data set of Culex pipiens sl. mosquitoes collected in Portugal mainland during seven years (2006-2012) and meteorological and physiographic parameters such as: air relative humidity, air temperature (minima, maxima and mean daily temperatures), daily total rainfall, altitude, land use/land cover and proximity to water bodies are evaluated. Focus is on the mosquito females; the characterization of its habitat is the key for the planning of chirurgical non-aggressive prophylactic countermeasures to avoid ambient degradation. The GIS allow for the spatial determination of the zones were the mosquito mean captures has been above average; using the meteorological values at these coordinates, the limits of each parameter are identified/computed. The meteorological parameters measured at the net of weather stations all over the country are averaged by month and interpolated to produce raster maps that can be segmented according to the thresholds obtained for each parameter. The intersection of the maps obtained for each month show the evolution of the area favorable to the species through the mosquito season, which is from May to October at these latitudes. In parallel, mean and above average captures were related to the physiographic parameters. Three levels of risk could be identified for each parameter, using above average captures as an index. The results were applied to the suitability meteorological maps of each month. The Culex pipiens critical niche is delimited, reflecting the critical areas and the level of risk for transmission of the pathogens to which they are competent vectors (West Nile virus, iridoviruses, rheoviruses and parvoviruses).Keywords: Culex pipiens, ecological niche, risk assessment, risk management
Procedia PDF Downloads 544917 Retrospective Statistical Study on the Evolution of Brucellosis during the Last Decade (2011-2021) in Medea, Algeria
Authors: Mammar Khames, Mustapha Oumouna
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Brucellosis is one of the most common zoonoses in the world. It represents a serious threat to human health; the existence of brucellosis in Algeria dates back to the beginning of the 19th century. Its transmission to humans is through coccobacilli of the genus Brucella following direct contact with contaminated animals or indirectly through the consumption of their unpasteurized dairy products. The present investigation covers a retrospective study on human brucellosis in the district of Medea over a period from 2011 to 2021 at the level of two public health establishments. In the first place, it is at the level of the Directorate of Public Health and in the infectious department level at Medea Hospital, and at the level of the directorate of agricultural services in the third place. The results showed that during these eleven years of study, 795 cases were collected from the department of health and population, and 141 cases were collected from the infectious department of the district of Medea. A total of 56 cases of bovine brucellosis were obtained from the directorate of agricultural services of the district of Medea. Human brucellosis affects all age groups with different percentages, but the rate has been higher in the 20-44 age group, with a predominance of men. However, the geographic distribution map of the cases shows that the western part of the district was the most affected. A cohort of 141 cases was hospitalized at the infectious service level of Medea Hospital. They were 89 men and 52 women. The most common age reached is [20-44] years. The majority were of rural origin. Two serological reactions were performed for diagnosis: the buffered antigen test and Wright's serodiagnosis. Bovine brucellosis affects all age groups with different percentages, but the rate was higher in the 2-to-4-year age group, with a predominance of females. From these data, we conclude that brucellosis has a strong spread in the region studied.Keywords: human brucellosis, serology, Medea, Algeria
Procedia PDF Downloads 63916 Using Large Databases and Interviews to Explore the Temporal Phases of Technology-Based Entrepreneurial Ecosystems
Authors: Elsie L. Echeverri-Carroll
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Entrepreneurial ecosystems have become an important concept to explain the birth and sustainability of technology-based entrepreneurship within regions. However, as a theoretical concept, the temporal evolution of entrepreneurship systems remain underdeveloped, making it difficult to understand their dynamic contributions to entrepreneurs. This paper argues that successful technology-based ecosystems go over three cumulative spawning stages: corporate spawning, entrepreneurial spawning, and community spawning. The importance of corporate incubation in vibrant entrepreneurial ecosystems is well documented in the entrepreneurial literature. Similarly, entrepreneurial spawning processes for venture capital-backed startups are well documented in the financial literature. In contrast, there is little understanding of both the third stage of entrepreneurial spawning (when a community of entrepreneurs become a source of firm spawning) and the temporal sequence in which spawning effects occur in a region. We test this three-stage model of entrepreneurial spawning using data from two large databases on firm births—the Secretary of State (160,000 observations) and the National Establishment Time Series (NEST with 150,000 observations)—and information collected from 60 1½-hour interviews with startup founders and representatives of key entrepreneurial organizations. This temporal model is illustrated with case study of Austin, Texas ranked by the Kauffman Foundation as the number one entrepreneurial city in the United States in 2015 and 2016. The 1½-year study founded by the Kauffman Foundation demonstrates the importance of taken into consideration the temporal contributions of both large and entrepreneurial firms in understanding the factors that contribute to the birth and growth of technology-based entrepreneurial regions. More important, these learnings could offer an important road map for regions that pursue to advance their entrepreneurial ecosystems.Keywords: entrepreneurial ecosystems, entrepreneurial industrial clusters, high-technology, temporal changes
Procedia PDF Downloads 272915 Study of Nanoclay Blends Based on PET/PEN Prepared by Reactive Extrusion
Authors: F. Zouai, F. Z. Benabid, S. Bouhelal, D. Benachour
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A new route of preparation of compatible blends, based on poly(ethylene terephthalate)(PET)/poly(ethylenenaphthalene2,6-dicarboxylate) (PEN)/clay nanocomposites has been successfully performed in one step by reactive melt extrusion. To achieve this, untreated clay was first purified and functionalized “in situ” with a compound based on an organic peroxide/sulfur mixture and (tetra methyl thiuram disulfide) TMTD as accelerator or activator for sulfur. The PET and PEN materials were first mixed separately in the melt state with different amounts of functionalized clay. It was observed that the compositions PET/4 wt% clay and PEN/7.5 wt% clay showed total exfoliation. These completely exfoliated compositions, called nPET and nPEN, respectively, were used to prepare new nPET/nPEN nanoblends in the same mixing batch. The nPET/nPEN nanoblends were compared to neat blends of PET/PEN. The blends and the nanocomposites were characterized by different techniques: differential scanning calorimetry (DSC) and wide-angle X-ray scattering (WAXS). The micro and nanostructure/properties relationships were investigated. The results of the WAXS measurements study showed that the exfoliation of tetrahedral nanolayers of clay was complete and the octahedral structure disappeared totally. From the different WAXS patterns, it is seen that all samples are amorphous phase. The thermal study showed that there are only one glass transition temperature Tg, one crystallization temperature Tc and one melting temperature Tm for every composition. This indicated that both PET/PEN blends and nPET/nPEN blends were compatible in the entire range of compositions. In addition, nPET/nPEN blends present lower Tc values and higher Tm values than the corresponding neat PET/PEN blends. The obtained results indicate that nPET/nPEN blends are somewhat different from the pure ones in nanostructure and behavior, thus showing the additional effect of nanolayers. The present study allowed establishing good correlations between the different measured properties.Keywords: PET, PEN, montmorillonite, nanocomposites, exfoliation, reactive melt-mixing
Procedia PDF Downloads 298914 ID + PD: Training Instructional Designers to Foster and Facilitate Learning Communities in Digital Spaces
Authors: Belkis L. Cabrera
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Contemporary technological innovations have reshaped possibility, interaction, communication, engagement, education, and training. Indeed, today, a high-quality technology enhanced learning experience can be transformative as much for the learner as for the educator-trainer. As innovative technologies continue to facilitate, support, foster, and enhance collaboration, problem-solving, creativity, adaptiveness, multidisciplinarity, and communication, the field of instructional design (ID) also continues to develop and expand. Shifting its focus from media to the systematic design of instruction, or rather from the gadgets and devices themselves to the theories, models, and impact of implementing educational technology, the evolution of ID marks a restructuring of the teaching, learning, and training paradigms. However, with all of its promise, this latter component of ID remains underdeveloped. The majority of ID models are crafted and guided by learning theories and, therefore, most models are constructed around student and educator roles rather than trainer roles. Thus, when these models or systems are employed for training purposes, they usually have to be re-fitted, tweaked, and stretched to meet the training needs. This paper is concerned with the training or professional development (PD) facet of instructional design and how ID models built on teacher-to-teacher interaction and dialogue can support the creation of professional learning communities (PLCs) or communities of practice (CoPs), which can augment learning and PD experiences for all. Just as technology is changing the face of education, so too can it change the face of PD within the educational realm. This paper not only provides a new ID model but using innovative technologies such as Padlet and Thinkbinder, this paper presents a concrete example of how a traditional body-to-body, brick, and mortar learning community can be transferred and transformed into the online context.Keywords: communities of practice, e-learning, educational reform, instructional design, professional development, professional learning communities, technology, training
Procedia PDF Downloads 340913 Vibration Analysis of FGM Sandwich Panel with Cut-Outs Using Refined Higher-Order Shear Deformation Theory (HSDT) Based on Isogeometric Analysis
Authors: Lokanath Barik, Abinash Kumar Swain
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This paper presents vibration analysis of FGM sandwich structure with a complex profile governed by refined higher-order shear deformation theory (RHSDT) using isogeometric analysis (IGA). Functionally graded sandwich plates provide a wide range of applications in aerospace, defence, and aircraft industries due to their ability to distribute material functions to influence the thermo-mechanical properties as desired. In practical applications, these structures generally have intrinsic profiles, and their response to loads is significantly affected due to cut-outs. IGA is primarily a NURBS-based technique that is effective in solving higher-order differential equations due to its inherent C1 continuity imposition in solution space for a single patch. Complex structures generally require multiple patches to accurately represent the geometry, and hence, there is a loss of continuity at adjoining patch junctions. Therefore, patch coupling is desired to maintain continuity requirements throughout the domain. In this work, a novel strong coupling approach is provided that generates a well-defined NURBS-based model while achieving continuity. The methodology is validated by free vibration analysis of sandwich plates with present literature. The results are in good agreement with the analytical solution for different plate configurations and power law indexes. Numerical examples of rectangular and annular plates are discussed with variable boundary conditions. Additionally, parametric studies are provided by varying the aspect ratio, porosity ratio and their influence on the natural frequency of the plate.Keywords: vibration analysis, FGM sandwich structure, multipatch geometry, patch coupling, IGA
Procedia PDF Downloads 82912 A Radiomics Approach to Predict the Evolution of Prostate Imaging Reporting and Data System Score 3/5 Prostate Areas in Multiparametric Magnetic Resonance
Authors: Natascha C. D'Amico, Enzo Grossi, Giovanni Valbusa, Ala Malasevschi, Gianpiero Cardone, Sergio Papa
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Purpose: To characterize, through a radiomic approach, the nature of areas classified PI-RADS (Prostate Imaging Reporting and Data System) 3/5, recognized in multiparametric prostate magnetic resonance with T2-weighted (T2w), diffusion and perfusion sequences with paramagnetic contrast. Methods and Materials: 24 cases undergoing multiparametric prostate MR and biopsy were admitted to this pilot study. Clinical outcome of the PI-RADS 3/5 was found through biopsy, finding 8 malignant tumours. The analysed images were acquired with a Philips achieva 1.5T machine with a CE- T2-weighted sequence in the axial plane. Semi-automatic tumour segmentation was carried out on MR images using 3DSlicer image analysis software. 45 shape-based, intensity-based and texture-based features were extracted and represented the input for preprocessing. An evolutionary algorithm (a TWIST system based on KNN algorithm) was used to subdivide the dataset into training and testing set and select features yielding the maximal amount of information. After this pre-processing 20 input variables were selected and different machine learning systems were used to develop a predictive model based on a training testing crossover procedure. Results: The best machine learning system (three-layers feed-forward neural network) obtained a global accuracy of 90% ( 80 % sensitivity and 100% specificity ) with a ROC of 0.82. Conclusion: Machine learning systems coupled with radiomics show a promising potential in distinguishing benign from malign tumours in PI-RADS 3/5 areas.Keywords: machine learning, MR prostate, PI-Rads 3, radiomics
Procedia PDF Downloads 188911 Dynamic and Thermal Characteristics of Three-Dimensional Turbulent Offset Jet
Authors: Ali Assoudi, Sabra Habli, Nejla Mahjoub Saïd, Philippe Bournot, Georges Le Palec
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Studying the flow characteristics of a turbulent offset jet is an important topic among researchers across the world because of its various engineering applications. Some of the common examples include: injection and carburetor systems, entrainment and mixing process in gas turbine and boiler combustion chambers, Thrust-augmenting ejectors for V/STOL aircrafts and HVAC systems, environmental dischargers, film cooling and many others. An offset jet is formed when a jet discharges into a medium above a horizontal solid wall parallel to the axis of the jet exit but which is offset by a certain distance. The structure of a turbulent offset-jet can be described by three main regions. Close to the nozzle exit, an offset jet possesses characteristic features similar to those of free jets. Then, the entrainment of fluid between the jet, the offset wall and the bottom wall creates a low pressure zone, forcing the jet to deflect towards the wall and eventually attaches to it at the impingement point. This is referred to as the Coanda effect. Further downstream after the reattachment point, the offset jet has the characteristics of a wall jet flow. Therefore, the offset jet has characteristics of free, impingement and wall jets, and it is relatively more complex compared to these types of flows. The present study examines the dynamic and thermal evolution of a 3D turbulent offset jet with different offset height ratio (the ratio of the distance from the jet exit to the impingement bottom wall and the jet nozzle diameter). To achieve this purpose a numerical study was conducted to investigate a three-dimensional offset jet flow through the resolution of the different governing Navier–Stokes’ equations by means of the finite volume method and the RSM second-order turbulent closure model. A detailed discussion has been provided on the flow and thermal characteristics in the form of streamlines, mean velocity vector, pressure field and Reynolds stresses.Keywords: offset jet, offset ratio, numerical simulation, RSM
Procedia PDF Downloads 304910 Normalized P-Laplacian: From Stochastic Game to Image Processing
Authors: Abderrahim Elmoataz
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More and more contemporary applications involve data in the form of functions defined on irregular and topologically complicated domains (images, meshs, points clouds, networks, etc). Such data are not organized as familiar digital signals and images sampled on regular lattices. However, they can be conveniently represented as graphs where each vertex represents measured data and each edge represents a relationship (connectivity or certain affinities or interaction) between two vertices. Processing and analyzing these types of data is a major challenge for both image and machine learning communities. Hence, it is very important to transfer to graphs and networks many of the mathematical tools which were initially developed on usual Euclidean spaces and proven to be efficient for many inverse problems and applications dealing with usual image and signal domains. Historically, the main tools for the study of graphs or networks come from combinatorial and graph theory. In recent years there has been an increasing interest in the investigation of one of the major mathematical tools for signal and image analysis, which are Partial Differential Equations (PDEs) variational methods on graphs. The normalized p-laplacian operator has been recently introduced to model a stochastic game called tug-of-war-game with noise. Part interest of this class of operators arises from the fact that it includes, as particular case, the infinity Laplacian, the mean curvature operator and the traditionnal Laplacian operators which was extensiveley used to models and to solve problems in image processing. The purpose of this paper is to introduce and to study a new class of normalized p-Laplacian on graphs. The introduction is based on the extension of p-harmonious function introduced in as discrete approximation for both infinity Laplacian and p-Laplacian equations. Finally, we propose to use these operators as a framework for solving many inverse problems in image processing.Keywords: normalized p-laplacian, image processing, stochastic game, inverse problems
Procedia PDF Downloads 512909 3-D Modeling of Particle Size Reduction from Micro to Nano Scale Using Finite Difference Method
Authors: Himanshu Singh, Rishi Kant, Shantanu Bhattacharya
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This paper adopts a top-down approach for mathematical modeling to predict the size reduction from micro to nano-scale through persistent etching. The process is simulated using a finite difference approach. Previously, various researchers have simulated the etching process for 1-D and 2-D substrates. It consists of two processes: 1) Convection-Diffusion in the etchant domain; 2) Chemical reaction at the surface of the particle. Since the process requires analysis along moving boundary, partial differential equations involved cannot be solved using conventional methods. In 1-D, this problem is very similar to Stefan's problem of moving ice-water boundary. A fixed grid method using finite volume method is very popular for modelling of etching on a one and two dimensional substrate. Other popular approaches include moving grid method and level set method. In this method, finite difference method was used to discretize the spherical diffusion equation. Due to symmetrical distribution of etchant, the angular terms in the equation can be neglected. Concentration is assumed to be constant at the outer boundary. At the particle boundary, the concentration of the etchant is assumed to be zero since the rate of reaction is much faster than rate of diffusion. The rate of reaction is proportional to the velocity of the moving boundary of the particle. Modelling of the above reaction was carried out using Matlab. The initial particle size was taken to be 50 microns. The density, molecular weight and diffusion coefficient of the substrate were taken as 2.1 gm/cm3, 60 and 10-5 cm2/s respectively. The etch-rate was found to decline initially and it gradually became constant at 0.02µ/s (1.2µ/min). The concentration profile was plotted along with space at different time intervals. Initially, a sudden drop is observed at the particle boundary due to high-etch rate. This change becomes more gradual with time due to declination of etch rate.Keywords: particle size reduction, micromixer, FDM modelling, wet etching
Procedia PDF Downloads 431908 Class Size Effects on Reading Achievement in Europe: Evidence from Progress in International Reading Literacy Study
Authors: Ting Shen, Spyros Konstantopoulos
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During the past three decades, class size effects have been a focal debate in education. The idea of having smaller class is enormously popular among parents, teachers and policy makers. The rationale of its popularity is that small classroom could provide a better learning environment in which there would be more teacher-pupil interaction and more individualized instruction. This early stage benefits would also have a long-term positive effect. It is a common belief that reducing class size may result in increases in student achievement. However, the empirical evidence about class-size effects from experimental or quasi-experimental studies has been mixed overall. This study sheds more light on whether class size reduction impacts reading achievement in eight European countries: Bulgaria, Germany, Hungary, Italy, Lithuania, Romania, Slovakia, and Slovenia. We examine class size effects on reading achievement using national probability samples of fourth graders. All eight European countries had participated in the Progress in International Reading Literacy Study (PIRLS) in 2001, 2006 and 2011. Methodologically, the quasi-experimental method of instrumental variables (IV) has been utilized to facilitate causal inference of class size effects. Overall, the results indicate that class size effects on reading achievement are not significant across countries and years. However, class size effects are evident in Romania where reducing class size increases reading achievement. In contrast, in Germany, increasing class size seems to increase reading achievement. In future work, it would be valuable to evaluate differential class size effects for minority or economically disadvantaged student groups or low- and high-achievers. Replication studies with different samples and in various settings would also be informative. Future research should continue examining class size effects in different age groups and countries using rich international databases.Keywords: class size, reading achievement, instrumental variables, PIRLS
Procedia PDF Downloads 291907 Orchids of Coastal Karnataka, India: Diversity, Trends in Population, Threats and Conservation Strategies
Authors: Sankaran Potti Narasimhan
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Costal Karnataka is sandwiched between Arabian Sea and the biodiversity hotspot of Western Ghats. This has provided a rich vegetation, canopy and humidity for the sustainable growth and evolution of many orchid populations. Similar to many other biodiversity hostpot regions of India and the world, this region also faces threat from anthropogenic activities and climate change. Hence, there is a need to study the current orchid diversity and trends in population as well as an effective conservation strategy. Costal belt of Karnataka state of India extends over 325 kilometers and an area of 18,000 km2. The region encompasses two national parks such as the Anshi National Park and the Kudremukh National Park. The study regions also include two Wild Life Sanctuaries such as the Someshwara Wildlife Sanctuary and Mookambika Wildlife Sanctuary. The estimated number of orchids in the region includes 30 genera and 45 species. Both terrestrial and epiphytic orchids are found in this region. The region contains many red listed orchids such as Trias stocksii (Critically endangered), Eriad alzellii (Lower risk vulnerable) and Dendrobnium ovatum (Vulnerable). The important terrestrial orchids of the region are Geodorum, Habenaria, Lipparis, Malaxis, Nervilia, Pachystoma, Pectelis, Peristylus, Tropidia and Zeuxine. The epiphytic forms includes Acampe, Aerides, Bulbophyllum, Cleisostoma, Conchidum, Cottonia, Cymbidium, Dendronium, Eria, Flickingeria, Gastrochilus, Kingidium, Luisia, Oberonia, Phalaenopsis, Pholidota, Porpax, Rhynchostylis, Sirhookera and Trias. The current paper discusses the population strength and changes in the population structure of these orchids along with proposed conservation strategies.Keywords: orchid diversity, bulbophyllum, dendrobium, orchid conservation
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