Search results for: texture profiles
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 1653

Search results for: texture profiles

303 Beyond Geometry: The Importance of Surface Properties in Space Syntax Research

Authors: Christoph Opperer

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Space syntax is a theory and method for analyzing the spatial layout of buildings and urban environments to understand how they can influence patterns of human movement, social interaction, and behavior. While direct visibility is a key factor in space syntax research, important visual information such as light, color, texture, etc., are typically not considered, even though psychological studies have shown a strong correlation to the human perceptual experience within physical space – with light and color, for example, playing a crucial role in shaping the perception of spaciousness. Furthermore, these surface properties are often the visual features that are most salient and responsible for drawing attention to certain elements within the environment. This paper explores the potential of integrating these factors into general space syntax methods and visibility-based analysis of space, particularly for architectural spatial layouts. To this end, we use a combination of geometric (isovist) and topological (visibility graph) approaches together with image-based methods, allowing a comprehensive exploration of the relationship between spatial geometry, visual aesthetics, and human experience. Custom-coded ray-tracing techniques are employed to generate spherical panorama images, encoding three-dimensional spatial data in the form of two-dimensional images. These images are then processed through computer vision algorithms to generate saliency-maps, which serve as a visual representation of areas most likely to attract human attention based on their visual properties. The maps are subsequently used to weight the vertices of isovists and the visibility graph, placing greater emphasis on areas with high saliency. Compared to traditional methods, our weighted visibility analysis introduces an additional layer of information density by assigning different weights or importance levels to various aspects within the field of view. This extends general space syntax measures to provide a more nuanced understanding of visibility patterns that better reflect the dynamics of human attention and perception. Furthermore, by drawing parallels to traditional isovist and VGA analysis, our weighted approach emphasizes a crucial distinction, which has been pointed out by Ervin and Steinitz: the difference between what is possible to see and what is likely to be seen. Therefore, this paper emphasizes the importance of including surface properties in visibility-based analysis to gain deeper insights into how people interact with their surroundings and to establish a stronger connection with human attention and perception.

Keywords: space syntax, visibility analysis, isovist, visibility graph, visual features, human perception, saliency detection, raytracing, spherical images

Procedia PDF Downloads 49
302 Exercise and Social Activities for Elderly with an Impairment Who Are Living Alone in the Community: Effects and Influencing Factors of a Dutch Program

Authors: Renate Verkaik, Mieke Rijken, Hennie Boeije

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Elderly who are living alone and who are having one or more impairments are vulnerable for a loss of wellbeing and institutionalization. Physical exercise and social activities together with peers have the potential to make them more resilient. The Dutch program ‘More Resilience, Longer at Home’ initiated by FNO funded 126 local projects to stimulate vulnerable older citizens to participate in exercise and social activities, and as such to improve wellbeing and independent living. The program evaluation addressed the following questions: (1) what are the effects of the program on older (65+) participants exercise behavior, social activities and what is the relationship with wellbeing?, (2) which factors contribute to successful implementation of the projects and their outcomes? A mixed method approach was used. Effects on participants were assessed with a short survey, containing questions on exercise, social engagement, daily functioning, loneliness and life satisfaction. Results of the participants were compared with those of a reference group from the Dutch national population. Perceived influencing factors were investigated with a questionnaire for project leaders. This questionnaire was based on site visits and interviews with project leaders, volunteers and participating elderly. Preliminary results show that social engagement of the participating elderly rises significantly (p ≤ .05) as do their exercise levels and daily functioning. They experience less social loneliness, but not less emotional loneliness. Additionally, there is a positive association between daily functioning and life satisfaction and between exercise and life satisfaction. Perceived influencing factors that contribute to successful implementation of the projects can be categorized in 4 types: (1) characteristics of the activities; (2) profiles of the involved staff (professionals and volunteers), (3) characteristics of the organization, (4) the social political environment. Conclusions are that local projects have been successful in stimulating older citizens to participate in exercise and social activities. Multiple factors need to be addressed to ensure sustainability and scaling-up of the good practices.

Keywords: elderly living alone in the community, exercise and social activities, resilience, quality of life

Procedia PDF Downloads 112
301 Site Specific Nutrient Management Need in India Now

Authors: A. H. Nanher, N. P. Singh, Shashidhar Yadav, Sachin Tyagi

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Agricultural production system is an outcome of a complex interaction of seed, soil, water and agro-chemicals (including fertilizers). Therefore, judicious management of all the inputs is essential for the sustainability of such a complex system. Precision agriculture gives farmers the ability to use crop inputs more effectively including fertilizers, pesticides, tillage and irrigation water. More effective use of inputs means greater crop yield and/or quality, without polluting the environment the focus on enhancing the productivity during the Green Revolution coupled with total disregard of proper management of inputs and without considering the ecological impacts, has resulted into environmental degradation. To evaluate a new approach for site-specific nutrient management (SSNM). Large variation in initial soil fertility characteristics and indigenous supply of N, P, and K was observed among Field- and season-specific NPK applications were calculated by accounting for the indigenous nutrient supply, yield targets, and nutrient demand as a function of the interactions between N, P, and K. Nitrogen applications were fine-tuned based on season-specific rules and field-specific monitoring of crop N status. The performance of SSNM did not differ significantly between high-yielding and low-yielding climatic seasons, but improved over time with larger benefits observed in the second year Future, strategies for nutrient management in intensive rice systems must become more site-specific and dynamic to manage spatially and temporally variable resources based on a quantitative understanding of the congruence between nutrient supply and crop demand. The SSNM concept has demonstrated promising agronomic and economic potential. It can be used for managing plant nutrients at any scale, i.e., ranging from a general recommendation for homogenous management of a larger domain to true management of between-field variability. Assessment of pest profiles in FFP and SSNM plots suggests that SSNM may also reduce pest incidence, particularly diseases that are often associated with excessive N use or unbalanced plant nutrition.

Keywords: nutrient, pesticide, crop, yield

Procedia PDF Downloads 408
300 Effects of Spectrotemporal Modulation of Music Profiles on Coherence of Cardiovascular Rhythms

Authors: I-Hui Hsieh, Yu-Hsuan Hu

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The powerful effect of music is often associated with changes in physiological responses such as heart rate and respiration. Previous studies demonstrate that Mayer waves of blood pressure, the spontaneous rhythm occurring at 0.1 Hz, corresponds to a progressive crescendo of the musical phrase. However, music contain dynamic changes in temporal and spectral features. As such, it remains unclear which aspects of musical structures optimally affect synchronization of cardiovascular rhythms. This study investigates the independent contribution of spectral pattern, temporal pattern, and dissonance level on synchronization of cardiovascular rhythms. The regularity of acoustical patterns occurring at a periodic rhythm of 0.1 Hz is hypothesized to elicit the strongest coherence of cardiovascular rhythms. Music excerpts taken from twelve pieces of Western classical repertoire were modulated to contain varying degrees of pattern regularity of the acoustic envelope structure. Three levels of dissonance were manipulated by varying the harmonic structure of the accompanying chords. Electrocardiogram and photoplethysmography signals were recorded for 5 minutes of baseline and simultaneously while participants listen to music excerpts randomly presented over headphones in a sitting position. Participants were asked to indicate the pleasantness of each music excerpt by adjusting via a slider presented on screen. Analysis of the Fourier spectral power of blood pressure around 0.1 Hz showed a significant difference between music excerpts characterized by spectral and temporal pattern regularity compared to the same content in random pattern. Phase coherence between heart rate and blood pressure increased significantly during listening to spectrally-regular phrases compared to its matched control phrases. The degree of dissonance of the accompanying chord sequence correlated with level of coherence between heart rate and blood pressure. Results suggest that low-level auditory features of music can entrain coherence of autonomic physiological variables. These findings have potential implications for using music as a clinical and therapeutic intervention for regulating cardiovascular functions.

Keywords: cardiovascular rhythms, coherence, dissonance, pattern regularity

Procedia PDF Downloads 127
299 Enhanced Cytotoxic Effect of Expanded NK Cells with IL12 and IL15 from Leukoreduction Filter on K562 Cell Line Exhibits Comparable Cytotoxicity to Whole Blood

Authors: Abdulbaset Mazarzaei

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Natural killer (NK) cells are innate immune effectors that play a pivotal role in combating tumors and infected cells. In recent years, the therapeutic potential of NK cells has gained significant attention due to their remarkable cytotoxic ability. This study focuses on investigating the cytotoxic effect of expanded NK cells enriched with interleukin 12 (IL12) and interleukin 15 (IL15), derived from the leukoreduction filter, on the K562 cell line. Firstly, NK cells were isolated from whole blood samples obtained from healthy volunteers. These cells were subsequently expanded ex vivo using a combination of feeder cells, IL12, and IL15. The expanded NK cells were then harvested and assessed for their cytotoxicity against K562, a well-established human chronic myelogenous leukemia cell line. The cytotoxicity was evaluated using flow cytometry assay. Results demonstrate that the expanded NK cells significantly exhibited enhanced cytotoxicity against K562 cells compared to non-expanded NK cells. Interestingly, the expanded NK cells derived specifically from IL12 and IL15-enriched leukoreduction filters showed a robust cytotoxic effect similar to the whole blood-derived NK cells. These findings suggest that IL12 and IL15 in the leukoreduction filter are crucial in promoting NK cell cytotoxicity. Furthermore, the expanded NK cells displayed relatively similar cytotoxicity profiles to whole blood-derived NK cells, indicating their comparable capability in targeting and eliminating tumor cells. This observation is of significant relevance as expanded NK cells from the leukoreduction filter could potentially serve as a readily accessible and efficient source for adoptive immunotherapy. In conclusion, this study highlights the significant cytotoxic effect of expanded NK cells enriched with IL12 and IL15 obtained from the leukoreduction filter on the K562 cell line. Moreover, it emphasizes that these expanded NK cells exhibit comparable cytotoxicity to whole blood-derived NK cells. These findings reinforce the potential clinical utility of using expanded NK cells from the leukoreduction filter as an effective strategy in adoptive immunotherapy for the treatment of cancer. Further studies are warranted to explore the broader implications of this approach in clinical settings.

Keywords: natural killer (NK) cells, Cytotoxicity, Leukoreduction filter, IL-12 and IL-15 Cytokines

Procedia PDF Downloads 45
298 The Importance of Working Memory, Executive and Attention Functions in Attention Deficit Hyperactivity Disorder and Learning Disabilities Diagnostics

Authors: Dorottya Horváth, Tímea Harmath-Tánczos

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Attention deficit hyperactivity disorder (ADHD) and learning disabilities are common neurocognitive disorders that can have a significant impact on a child's academic performance. ADHD is characterized by inattention, hyperactivity, and impulsivity, while learning disabilities are characterized by difficulty with specific academic skills, such as reading, writing, or math. The aim of this study was to investigate the working memory, executive, and attention functions of neurotypical children and children with ADHD and learning disabilities in order to fill the gaps in the Hungarian mean test scores of these cognitive functions in children with neurocognitive disorders. Another aim was to specify the neuropsychological differential diagnostic toolkit in terms of the relationships and peculiarities between these cognitive functions. The research question addressed in this study was: How do the working memory, executive, and attention functions of neurotypical children compare to those of children with ADHD and learning disabilities? A self-administered test battery was used as a research tool. Working memory was measured with the Non-Word Repetition Test, the Listening Span Test, the Digit Span Test, and the Reverse Digit Span Test; executive function with the Letter Fluency, Semantic Fluency, and Verb Fluency Tests; and attentional concentration with the d2-R Test. The data for this study was collected from 115 children aged 9-14 years. The children were divided into three groups: neurotypical children (n = 44), children with ADHD without learning disabilities (n = 23), and children with ADHD with learning disabilities (n = 48). The data was analyzed using a variety of statistical methods, including t-tests, ANOVAs, and correlational analyses. The results showed that the performance of children with neurocognitive involvement in working memory, executive functions, and attention was significantly lower than the performance of neurotypical children. However, the results of children with ADHD and ADHD with learning disabilities did not show a significant difference. The findings of this study are important because they provide new insights into the cognitive profiles of children with ADHD and learning disabilities and suggest that working memory, executive functions, and attention are all impaired in children with neurocognitive involvement, regardless of whether they have ADHD or learning disabilities. This information can be used to develop more effective diagnostic and treatment strategies for these disorders.

Keywords: ADHD, attention functions, executive functions, learning disabilities, working memory

Procedia PDF Downloads 71
297 Responsive Integrative Therapeutic Method: Paradigm for Addressing Core Deficits in Autism by Balkibekova

Authors: Balkibekova Venera Serikpaevna

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Background: Autism Spectrum Disorder (ASD) poses significant challenges in both diagnosis and treatment. Existing therapeutic interventions often target specific symptoms, necessitating the exploration of alternative approaches. This study investigates the RITM (Rhythm Integration Tapping Music) developed by Balkibekova, aiming to create imitation, social engagement and a wide range of emotions through brain development. Methods: A randomized controlled trial was conducted with 100 participants diagnosed with ASD, aged 1 to 4 years. Participants were randomly assigned to either the RITM therapy group or a control group receiving standard care. The RITM therapy, rooted in tapping rhythm to music such as: marche on the drums, waltz on bells, lullaby on musical triangle, dancing on tambourine, polka on wooden spoons. Therapy sessions were conducted over a 3 year period, with assessments at baseline, midpoint, and post-intervention. Results: Preliminary analyses reveal promising outcomes in the RITM therapy group. Participants demonstrated significant improvements in social interactions, speech understanding, birth of speech, and adaptive behaviors compared to the control group. Careful examination of subgroup analyses provides insights into the differential effectiveness of the RITM approach across various ASD profiles. Conclusions: The findings suggest that RITM therapy, as developed by Balkibekova, holds promise as intervention for ASD. The integrative nature of the approach, addressing multiple domains simultaneously, may contribute to its efficacy. Further research is warranted to validate these preliminary results and explore the long-term impact of RITM therapy on individuals with ASD. This abstract presents a snapshot of the research, emphasizing the significance, methodology, key findings, and implications of the RITM therapy method for consideration in an autism conference.

Keywords: RITM therapy, tapping rhythm, autism, mirror neurons, bright emotions, social interactions, communications

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296 Poly(N-Vinylcaprolactam-Co-Itaconic Acid-Co-Ethylene Glycol Dimethacrylate)-Based Microgels Embedded in Chitosan Matrix for Controlled Release of Ketoprofen

Authors: Simone F. Medeiros, Jessica M. Fonseca, Gizelda M. Alves, Danilo M. Santos, Sérgio P. Campana-Filho, Amilton M. Santos

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Stimuli responsive and biocompatible hydrogel nanoparticles have gained special attention as systems for potential applications in controlled release of drugs to improve their therapeutic efficacy while minimizing side effects. In this work, novel solid dispersions based on thermo- and pH-responsive poly(N-vinylcaprolactam-co-itaconic acid-co-ethylene- glycol dimethacrylate) hydrogel nanoparticles embedded in chitosan matrices were prepared via spray drying for controlled release of ketoprofen. Firstly, the hydrogel nanoparticles containing ketoprofen were prepared via precipitation polymerization and their stimuli-responsive behavior, thermal properties, chemical composition, encapsulation efficiency and morphology were characterized. Then, hydrogel nanoparticles with different particles size were embedded into chitosan matrices via spray-drying. Scanning electron microscopy (SEM) analyses were performed to investigate the particles size, dispersity and morphology. Finally, ketoprofen release profiles were studied as a function of pH and temperature. Chitosan/poly(NVCL-co-IA-co-EGDMA)-ketoprofen microparticles presented spherical shape, rough surface and pronounced agglomeration, indicating that hydrogels nanoparticles loaded with ketoprofen modified the surface of chitosan matrix. The maximum encapsulation efficiency of ketoprofen into hydrogel nanoparticles was 57.8% and the electrostatic interactions between amino groups from chitosan and carboxylic groups from hydrogel nanoparticles were able to control ketoprofen release. The hydrogel nanoparticles themselves were capable to retard the release of ketoprofen-loaded until 48h of in vitro release tests, while their incorporation into chitosan matrix achieved a maximum percentage of drug release of 45%, using a mass ratio of chitosan: poly(NVCL-co-IA-co-EGDMA equal to 10:7, and 69%, using a mass ratio of chitosan: poly(NVCL-co-IA-co-EGDMA equal to 5:2.

Keywords: hydrogel nanoparticles, poly(N-vinylcaprolactam-co-itaconic acid-co-ethylene- glycol dimethacrylate), chitosan, ketoprofen, spray-drying

Procedia PDF Downloads 237
295 Carl Wernicke and the Origin of Neurolinguistics in Breslau: A Case Study in the Domain of the History of Linguistics

Authors: Aneta Daniel

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The subject of the study is the exploration of the origins and dynamics of the development of language studies, which have been labelled as neurolinguistics. It is worth mentioning that the origins of neurolinguistics are to be found in the research conducted by German scientists before the Second World War in Breslau Universität (presently Wroclaw). The dominant figure in these studies was professor Carl Wernicke, whose students continued and creatively developed projects of their master within this area. Professor Carl Wernicke, a German physician, anatomist, psychiatrist, and neuropathologist, is primarily known for his influential research on aphasia. His research, as well as those conducted by professor Paul Broca, has led to breakthroughs in the location of brain functions, particularly speech. Years later the theses of the pioneers of cognitive neurology (Carl Wernicke and Paul Broca) were developed by other neurolinguists. The main objective of the investigation is the reconstruction of the group of scientists –the students of Carl Wernicke– who contributed to the development of neurolinguistics. The scholars were mainly neurologists and psychiatrists and dealt with the branch of science that had not been named neurolinguistics at that time. The profiles of the scholars will be analysed and presented as the members of the group of researchers who have contributed to the breakthroughs in psychology and neuroscience. The research material consists of archival records documenting the research of professor Carl Wernicke and the researchers from Breslau (presently Wroclaw) which is one of the fastest growing cities in Europe. In 1870, when Carl Wernicke became the medical doctor, Breslau was full of cultural events: festivals and circus shows were held in the city center. Today we can come back to these events due to 'Breslauer Zeitung (1870)', which precisely describes all the events that took place on particular days. It is worth noting that those were the beginnings of antisemitism in Breslau. Many theses and articles that have survived in the libraries in Wroclaw and all over the world contribute to the development of neuroscience. The history of research on the brain and speech analysis, including the history of psychology and neuroscience, areas from which neurolinguistics is derived, will be presented.

Keywords: Aphasia, brain injury, Carl Wernicke, language, neurolinguistics

Procedia PDF Downloads 351
294 Cellular RNA-Binding Domains with Distant Homology in Viral Proteomes

Authors: German Hernandez-Alonso, Antonio Lazcano, Arturo Becerra

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Until today, viruses remain controversial and poorly understood; about their origin, this problem represents an enigma and one of the great challenges for the contemporary biology. Three main theories have tried to explain the origin of viruses: regressive evolution, escaped host gene, and pre-cellular origin. Under the perspective of the escaped host gene theory, it can be assumed a cellular origin of viral components, like protein RNA-binding domains. These universal distributed RNA-binding domains are related to the RNA metabolism processes, including transcription, processing, and modification of transcripts, translation, RNA degradation and its regulation. In the case of viruses, these domains are present in important viral proteins like helicases, nucleases, polymerases, capsid proteins or regulation factors. Therefore, they are implicated in the replicative cycle and parasitic processes of viruses. That is why it is possible to think that those domains present low levels of divergence due to selective pressures. For these reasons, the main goal for this project is to create a catalogue of the RNA-binding domains found in all the available viral proteomes, using bioinformatics tools in order to analyze its evolutionary process, and thus shed light on the general virus evolution. ProDom database was used to obtain larger than six thousand RNA-binding domain families that belong to the three cellular domains of life and some viral groups. From the sequences of these families, protein profiles were created using HMMER 3.1 tools in order to find distant homologous within greater than four thousand viral proteomes available in GenBank. Once accomplished the analysis, almost three thousand hits were obtained in the viral proteomes. The homologous sequences were found in proteomes of the principal Baltimore viral groups, showing interesting distribution patterns that can contribute to understand the evolution of viruses and their host-virus interactions. Presence of cellular RNA-binding domains within virus proteomes seem to be explained by closed interactions between viruses and their hosts. Recruitment of these domains is advantageous for the viral fitness, allowing viruses to be adapted to the host cellular environment.

Keywords: bioinformatics tools, distant homology, RNA-binding domains, viral evolution

Procedia PDF Downloads 363
293 Effect of Different Sterilization Processes on Drug Loaded Silicone-Hydrogel

Authors: Raquel Galante, Marina Braga, Daniela Ghisleni, Terezinha J. A. Pinto, Rogério Colaço, Ana Paula Serro

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The sensitive nature of soft biomaterials, such as hydrogels, renders their sterilization a particularly challenging task for the biomedical industry. Widely used contact lenses are now studied as promising platforms for topical corneal drug delivery. However, to the best of the authors knowledge, the influence of sterilization methods on these systems has yet to be evaluated. The main goal of this study was to understand how different pairs drug-hydrogel would interact under an ozone-based sterilization method in comparison with two conventional processes (steam heat and gamma irradiation). For that, Si-Hy containing hydroxylethyl methacrylate (HEMA) and [tris(trimethylsiloxy)silyl]propyl methacrylate (TRIS) was produced and soaked in different drug solutions, commonly used for the treatment of ocular diseases (levofloxacin, chlorhexidine, diclofenac and timolol maleate). The drug release profiles and main material properties were evaluated before and after the sterilization. Namely, swelling capacity was determined by water uptake studies, transparency was accessed by UV-Vis spectroscopy, surface topography/morphology by scanning electron microscopy (SEM) and mechanical properties by performing tensile tests. The drug released was quantified by high performance liquid chromatography (HPLC). The effectiveness of the sterilization procedures was assured by performing sterility tests. Ozone gas method led to a significant reduction of drug released and to the formation of degradation products specially for diclofenac and levofloxacin. Gamma irradiation led to darkening of the loaded Si-Hys and to the complete degradation of levofloxacin. Steam heat led to smoother surfaces and to a decrease of the amount of drug released, however, with no formation of degradation products. This difference in the total drug released could be the related to drug/polymer interactions promoted by the sterilization conditions in presence of the drug. Our findings offer important insights that, in turn, could be a useful contribution to the safe development of actual products.

Keywords: drug delivery, silicone hydrogels, sterilization, gamma irradiation, steam heat, ozone gas

Procedia PDF Downloads 289
292 Activation of NLRP3 Inflammasomes by Helicobacter pylori Infection in Innate Cellular Model and Its Correlation to IL-1β Production

Authors: Islam Nowisser, Noha Farag, Mohamed El Azizi

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Helicobacter pylori is a highly important human pathogen which inhabits about 50% of the population worldwide. Infection with this bacteria is very hard to treat, with high probability of recurrence. H. pylori causes severe gastric diseases, including peptic ulcer, gastritis, and gastric cancer, which has been linked to chronic inflammation. The infection has been reported to be associated with high levels of pro-inflammatory cytokines, especially IL-1β and TNF-α. The aim of the current study is to investigate the molecular mechanisms by which H. pylori activates NLRP3 inflammasome and its contribution to Il-1 β production in an innate cellular model. H. pylori PMSS1 and G27 standard strains, as well as the PMSS1 isogenic mutant strain PMSS1ΔVacA and G27ΔVacA, G27ΔCagA in addition to clinical isolates obtained from biopsy samples from the antrum and corpus mucosa of chronic gastritis patients, were used to establish infection in RAW-264.7 macrophages. The production levels of TNF-α and IL-1β was assessed using ELISA. Since expression of these cytokines is often regulated by the transcription factor complex, nuclear factor-kB (NF-kB), the activation of NF-κB in H. pylori infected cells was also evaluated by luciferase assay. Genomic DNA was extracted from bacterial cultures of H. pylori clinical isolates as well as the standard strains and their corresponding mutants, where they were evaluated for the cagA pathogenicity island and vacA expression. The correlation between these findings and expression of the cagA Pathogenicity Island and vacA in the bacteria was also investigated. The results showed IL-1β, and TNF-α production significantly increased in raw macrophages following H. pylori infection. The cagA+ and vacA+ H. pylori strains induced significant production of IL-1β compared to cagA- and vacA- strains. The activation pattern of NF-κB was correlated in the isolates to their cagA and vacA expression profiles. A similar finding could not be confirmed for TNF-α production. Our study shows the ability of H. pylori to activate NF-kB and induce significant IL-1β production as a possible mechanism for the augmented inflammatory response seen in subjects infected with cagA+ and vacA+ H. pylori strains that would lead to the progression to more severe form of the disease.

Keywords: Helicobacter pylori, IL-1β, inflammatory cytokines, nuclear factor KB, TNF-α

Procedia PDF Downloads 104
291 Multi-omics Integrative Analysis with Genome-Scale Metabolic Model Simulation Reveals Reaction Essentiality data in Human Astrocytes Under the Lipotoxic Effect of Palmitic Acid

Authors: Janneth Gonzalez, Andres Pinzon Velasco, Maria Angarita, Nicolas Mendoza

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Astrocytes play an important role in various processes in the brain, including pathological conditions such as neurodegenerative diseases. Recent studies have shown that the increase in saturated fatty acids such as palmitic acid (PA) triggers pro-inflammatory pathways in the brain. The use of synthetic neurosteroids such as tibolone has demonstrated neuro-protective mechanisms. However, there are few studies on the neuro-protective mechanisms of tibolone, especially at the systemic (omic) level. In this study, we performed the integration of multi-omic data (transcriptome and proteome) into a human astrocyte genomic scale metabolic model to study the astrocytic response during palmitate treatment. We evaluated metabolic fluxes in three scenarios (healthy, induced inflammation by PA, and tibolone treatment under PA inflammation). We also use control theory to identify those reactions that control the astrocytic system. Our results suggest that PA generates a modulation of central and secondary metabolism, showing a change in energy source use through inhibition of folate cycle and fatty acid β-oxidation and upregulation of ketone bodies formation.We found 25 metabolic switches under PA-mediated cellular regulation, 9 of which were critical only in the inflammatory scenario but not in the protective tibolone one. Within these reactions, inhibitory, total, and directional coupling profiles were key findings, playing a fundamental role in the (de)regulation in metabolic pathways that increase neurotoxicity and represent potential treatment targets. Finally, this study framework facilitates the understanding of metabolic regulation strategies, andit can be used for in silico exploring the mechanisms of astrocytic cell regulation, directing a more complex future experimental work in neurodegenerative diseases.

Keywords: astrocytes, data integration, palmitic acid, computational model, multi-omics, control theory

Procedia PDF Downloads 99
290 Investigation of Heat Conduction through Particulate Filled Polymer Composite

Authors: Alok Agrawal, Alok Satapathy

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In this paper, an attempt to determine the effective thermal conductivity (keff) of particulate filled polymer composites using finite element method (FEM) a powerful computational technique is made. A commercially available finite element package ANSYS is used for this numerical analysis. Three-dimensional spheres-in-cube lattice array models are constructed to simulate the microstructures of micro-sized particulate filled polymer composites with filler content ranging from 2.35 to 26.8 vol %. Based on the temperature profiles across the composite body, the keff of each composition is estimated theoretically by FEM. Composites with similar filler contents are than fabricated using compression molding technique by reinforcing micro-sized aluminium oxide (Al2O3) in polypropylene (PP) resin. Thermal conductivities of these composite samples are measured according to the ASTM standard E-1530 by using the Unitherm™ Model 2022 tester, which operates on the double guarded heat flow principle. The experimentally measured conductivity values are compared with the numerical values and also with those obtained from existing empirical models. This comparison reveals that the FEM simulated values are found to be in reasonable good agreement with the experimental data. Values obtained from the theoretical model proposed by the authors are also found to be in even closer approximation with the measured values within percolation limit. Further, this study shows that there is gradual enhancement in the conductivity of PP resin with increase in filler percentage and thereby its heat conduction capability is improved. It is noticed that with addition of 26.8 vol % of filler, the keff of composite increases to around 6.3 times that of neat PP. This study validates the proposed model for PP-Al2O3 composite system and proves that finite element analysis can be an excellent methodology for such investigations. With such improved heat conduction ability, these composites can find potential applications in micro-electronics, printed circuit boards, encapsulations etc.

Keywords: analytical modelling, effective thermal conductivity, finite element method, polymer matrix composite

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289 An Analytical Formulation of Pure Shear Boundary Condition for Assessing the Response of Some Typical Sites in Mumbai

Authors: Raj Banerjee, Aniruddha Sengupta

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An earthquake event, associated with a typical fault rupture, initiates at the source, propagates through a rock or soil medium and finally daylights at a surface which might be a populous city. The detrimental effects of an earthquake are often quantified in terms of the responses of superstructures resting on the soil. Hence, there is a need for the estimation of amplification of the bedrock motions due to the influence of local site conditions. In the present study, field borehole log data of Mangalwadi and Walkeswar sites in Mumbai city are considered. The data consists of variation of SPT N-value with the depth of soil. A correlation between shear wave velocity (Vₛ) and SPT N value for various soil profiles of Mumbai city has been developed using various existing correlations which is used further for site response analysis. MATLAB program is developed for studying the ground response analysis by performing two dimensional linear and equivalent linear analysis for some of the typical Mumbai soil sites using pure shear (Multi Point Constraint) boundary condition. The model is validated in linear elastic and equivalent linear domain using the popular commercial program, DEEPSOIL. Three actual earthquake motions are selected based on their frequency contents and durations and scaled to a PGA of 0.16g for the present ground response analyses. The results are presented in terms of peak acceleration time history with depth, peak shear strain time history with depth, Fourier amplitude versus frequency, response spectrum at the surface etc. The peak ground acceleration amplification factors are found to be about 2.374, 3.239 and 2.4245 for Mangalwadi site and 3.42, 3.39, 3.83 for Walkeswar site using 1979 Imperial Valley Earthquake, 1989 Loma Gilroy Earthquake and 1987 Whitter Narrows Earthquake, respectively. In the absence of any site-specific response spectrum for the chosen sites in Mumbai, the generated spectrum at the surface may be utilized for the design of any superstructure at these locations.

Keywords: deepsoil, ground response analysis, multi point constraint, response spectrum

Procedia PDF Downloads 162
288 Blood Profile, Organs, and Carcass Analysis and Performance of Broilers Fed Cowpea Testa Based Diet

Authors: O. J. Osunkeye, P. O. Fakolade, B. E. Olorede

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Broilers productions depend on the provision of adequate and goo quality feed containing all the nutrients, including proteins, carbohydrate, fats, vitamins, minerals and water. All these nutrients have to be provided at a required amount to support maximum productivity and normal physiological functions and demands. Among these nutrients proteins are particularly important, since they are essential for meat and muscle production, optimum growth and health status. Poultry production industry in the developing countries is been threatened because of the over dependency on Soybean meal as one of the key/major conventional protein stuff for feeding livestock. Even the competition between man and livestock for Soybean and other protein sources made the price of this feed stuff to be on the increase. Hence the needs to seek for an alternative feed stuff which is cheap and less competitive. This study showed the blood profile, organ and carcass characteristics and performance of broilers fed with Cowpea Testa Meal (CTM) based diets. Four diets were formulated with Cowpea Testa replacing Soybean at 0%, 15%, 30%, and 50% graded levels. One hundred and twenty day-old unsexed broiler birds were allotted to these four treatments with 3 replicates of 10 birds per replicate. The results showed no significant differences in all the haematological parameters measured (P>0.05), the serum metabolites analysis revealed significant different in Cholesterol (99.8 mg/dl, 112.84 mg/dl, 131.07 mg/dl and 97.66 mg/dl respectively) (P<0.05) among others. There were significant differences within the diets for average daily weight gain, average feed intake and feed to gain ratio. The birds on control (0%) and CTM gained more weight than those fed with 30% and 50% CTM diets. The organs and carcass primal cuts of the broilers expressed significant different for the spleen (0.12 g, 0.09 g, 0.11 g and 0.14 g respectively), lungs (0.97 g, 0.72 g, 0.77 g and 1.01g respectively) and proventriculus (0.96 g, 0.99 g, 0.81 g and 0.85 g respectively) (P<0.05). For the carcass, there were no significant differences (P<0.05) in the breast, thigh, drumstick, wing and neck except for the Back (21.27 g, 21.04 g, 17.71 g, and 17.89 g respectively). In conclusion, CTM inclusion in broiler’s diet could be used as an alternative feed stuff in replacement of Soybean meal up to 15% without any adverse effects as revealed by the blood profile and to increase the growth performance of the birds.

Keywords: physiological functions, cholesterol, blood profiles, CTM and carcass analysis

Procedia PDF Downloads 590
287 Association of 105A/C IL-18 Gene Single Nucleotide Polymorphism with House Dust Mite Allergy in an Atopic Filipino Population

Authors: Eisha Vienna M. Fernandez, Cristan Q. Cabanilla, Hiyasmin Lim, John Donnie A. Ramos

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Allergy is a multifactorial disease affecting a significant proportion of the population. It is developed through the interaction of allergens and the presence of certain polymorphisms in various susceptibility genes. In this study, the correlation of the 105A/C single nucleotide polymorphism (SNP) of the IL-18 gene and house dust mite-specific IgE among Filipino allergic and non-allergic population was investigated. Atopic status was defined by serum total IgE concentration of ≥100 IU/mL, while house dust mite allergy was defined by specific IgE value ≥ +1SD of IgE of nonatopic participants. Two hundred twenty match-paired Filipino cases and controls aged 6-60 were the subjects of this investigation. The level of total IgE and Specific IgE were measured using Enzyme-Linked Immunosorbent Assay (ELISA) while Polymerase Chain Reaction – Restriction Fragment Length Polymorphism (PCR-RFLP) analysis was used in the SNP detection. Sensitization profiles of the allergic patients revealed that 97.3% were sensitized to Blomia tropicalis, 40.0% to Dermatophagoides farinae, and 29.1% to Dermatophagoides pteronyssinus. Multiple sensitization to HDMs was also observed among the 47.27% of the atopic participants. Any of the allergy classes of the atopic triad were exhibited by the cases (allergic asthma: 48.18%; allergic rhinitis: 62.73%; atopic dermatitis: 19.09%), and two or all of these atopic states are concurrently occurring in 26.36% of the cases. A greater proportion of the atopic participants with allergic asthma and allergic rhinitis were sensitized to D. farinae, and D. pteronyssinus, while more of those with atopic dermatitis were sensitized to D. pteronyssinus than D. farinae. Results show that there is overrepresentation of the allele “A” of the 105A/C IL-18 gene SNP in both cases and control groups of the population. The genotype that predominate the population is the heterozygous “AC”, followed by the homozygous wild “AA”, and the homozygous variant “CC” being the least. The study confirmed a positive association between serum specific IgE against B. tropicalis and D. pteronyssinus and the allele “C” (Bt P=0.021, Dp P=0.027) and “AC” (Bt P=0.003, Dp P=0.026) genotype. Findings also revealed that the genotypes “AA” (OR:1.217; 95% CI: 0.701-2.113) and “CC” (OR, 3.5; 95% CI: 0.727-16.849) increase the risk of developing allergy. This indicates that the 105A/C IL-18 gene SNP is a candidate genetic marker for HDM allergy among Filipino patients.

Keywords: house dust mite allergy, interleukin-18 (IL-18), single nucleotide polymorphism,

Procedia PDF Downloads 440
286 The Impacts of the Sit-Stand Workplace Intervention on Cardiometabolic Risk

Authors: Rebecca M. Dagger, Katy Hadgraft, Matthew Teggart, Peter Angell

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Background: There is a growing body of evidence that demonstrates the association between sedentary behaviour, cardiometabolic risk and all-cause mortality. Since full time working adults spend approximately 8 hours per day in the workplace, interventions to reduce sedentary behaviour at work may alleviate some of the negative health outcomes associated with sedentary behaviour. The aims of this pilot study were to assess the impacts of using a Sit-Stand workstation on markers of cardiometabolic health in a cohort of desk workers. Methods: Twenty eight participants were recruited and randomly assigned to a control (n=5 males, 9 females, mean age 37 years ± 9.4 years) or intervention group (n= 5 males, 9 females, mean age 42 years ± 12.7 years). All participants attended the labs on 2 occasion’s pre and post intervention, following baseline measurements the intervention participants had the Sit Stand Workstations (Ergotron, USA) installed for a 10 week intervention period. The Sit Stand workstations allow participants to stand or sit at their usual workstation and participants were encouraged to the use the desk in a standing position at regular intervals throughout the working day. Cardiometabolic risk markers assessed were body mass, body composition (using bio impedance analysis; Tanita, Tokyo), fasting blood Total Cholesterol (TC), lipid profiles (HDL-C, LDL-C, TC: HDL-C ratio), triglycerides and fasting glucose (Cholestech LDX), resting systolic and diastolic blood pressure and resting heart rate. ANCOVA controlling for baseline values was used to assess the group difference in changes in risk markers between pre and post intervention. Results: The 10 week intervention was associated with significant reductions in some cardiometabolic risk factors. There were significant group effects on change in body mass (F (1,25)=5.915, p<0.05), total body fat percentage (F(1,25)=12.615, p<0.01), total fat mass (F (1,25)=6.954, p<0.05), and systolic blood pressure (F (1,25)=5.012, p<0.05). There were no other significant group effects on changes in other cardiometabolic risk markers. Conclusion: This pilot study highlights the importance of reducing sedentary behaviour in the workplace for reduction in cardiometabolic risk markers. Further research is required to support these findings.

Keywords: sedentary behaviour, caridometabolic risk, evidence, risk makers

Procedia PDF Downloads 419
285 Development and Characterization of Expandable TPEs Compounds for Footwear Applications

Authors: Ana Elisa Ribeiro Costa, Sónia Daniela Ferreira Miranda, João Pedro De Carvalho Pereira, João Carlos Simões Bernardo

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Elastomeric thermoplastics (TPEs) have been widely used in the footwear industry over the years. Recently this industry has been requesting materials that can combine lightweight and high abrasion resistance. Although there are blowing agents on the market to improve the lightweight, when these are incorporated into molten polymers during the extrusion or injection molding, it is necessary to have some specific processing conditions (e.g. effect of temperature and hydrodynamic stresses) to obtain good properties and acceptable surface appearance on the final products. Therefore, it is a great advantage for the compounder industry to acquire compounds that already include the blowing agents. In this way, they can be handled and processed under the same conditions as a conventional raw material. In this work, the expandable TPEs compounds, namely a TPU and a SEBS, with the incorporation of blowing agents, have been developed through a co-rotating modular twin-screw parallel extruder. Different blowing agents such as thermo-expandable microspheres and an azodicarbonamide were selected and different screw configurations and temperature profiles were evaluated since these parameters have a particular influence on the expansion inhibition of the blowing agents. Furthermore, percentages of incorporation were varied in order to investigate their influence on the final product properties. After the extrusion of these compounds, expansion was tested by the injection process. The mechanical and physical properties were characterized by different analytical methods like tensile, flexural and abrasive tests, determination of hardness and density measurement. Also, scanning electron microscopy (SEM) was performed. It was observed that it is possible to incorporate the blowing agents on the TPEs without their expansion on the extrusion process. Only with reprocessing (injection molding) did the expansion of the agents occur. These results are corroborated by SEM micrographs, which show a good distribution of blowing agents in the polymeric matrices. The other experimental results showed a good mechanical performance and its density decrease (30% for SEBS and 35% for TPU). This study suggested that it is possible to develop optimized compounds for footwear applications (e.g., sole shoes), which only will be able to expand during the injection process.

Keywords: blowing agents, expandable thermoplastic elastomeric compounds, low density, footwear applications

Procedia PDF Downloads 176
284 Reactive Transport Modeling in Carbonate Rocks: A Single Pore Model

Authors: Priyanka Agrawal, Janou Koskamp, Amir Raoof, Mariette Wolthers

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Calcite is the main mineral found in carbonate rocks, which form significant hydrocarbon reservoirs and subsurface repositories for CO2 sequestration. The injected CO2 mixes with the reservoir fluid and disturbs the geochemical equilibrium, triggering calcite dissolution. Different combinations of fluid chemistry and injection rate may therefore result in different evolution of porosity, permeability and dissolution patterns. To model the changes in porosity and permeability Kozeny-Carman equation K∝〖(∅)〗^n is used, where K is permeability and ∅ is porosity. The value of n is mostly based on experimental data or pore network models. In pore network models, this derivation is based on accuracy of relation used for conductivity and pore volume change. In fact, at a single pore scale, this relationship is the result of the pore shape development due to dissolution. We have prepared a new reactive transport model for a single pore which simulates the complex chemical reaction of carbonic-acid induced calcite dissolution and subsequent pore-geometry evolution at a single pore scale. We use COMSOL Multiphysics package 5.3 for the simulation. COMSOL utilizes the arbitary-Lagrangian Eulerian (ALE) method for the free-moving domain boundary. We examined the effect of flow rate on the evolution of single pore shape profiles due to calcite dissolution. We used three flow rates to cover diffusion dominated and advection-dominated transport regimes. The fluid in diffusion dominated flow (Pe number 0.037 and 0.37) becomes less reactive along the pore length and thus produced non-uniform pore shapes. However, for the advection-dominated flow (Pe number 3.75), the fast velocity of the fluid keeps the fluid relatively more reactive towards the end of the pore length, thus yielding uniform pore shape. Different pore shapes in terms of inlet opening vs overall pore opening will have an impact on the relation between changing volumes and conductivity. We have related the shape of pore with the Pe number which controls the transport regimes. For every Pe number, we have derived the relation between conductivity and porosity. These relations will be used in the pore network model to get the porosity and permeability variation.

Keywords: single pore, reactive transport, calcite system, moving boundary

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283 Screening of Phytochemicals Compounds from Chasmanthera dependens and Carissa edulis as Potential Inhibitors of Carbonic Anhydrases CA II (3HS4) Receptor using a Target-Based Drug Design

Authors: Owonikoko Abayomi Dele

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Epilepsy is an unresolved disease that needs urgent attention. It is a brain disorder that affects over sixty-five (65) million people around the globe. Despite the availability of commercial anti-epileptic drugs, the war against this unmet condition is yet to be resolved. Most epilepsy patients are resistant to available anti-epileptic medications thus the need for affordable novel therapy against epilepsy is a necessity. Numerous phytochemicals have been reported for their potency, efficacy and safety as therapeutic agents against many diseases. This study investigated 99 isolated phytochemicals from Chasmanthera dependens and Carissa edulis against carbonic anhydrase (ii) drug target. The absorption, distribution, metabolism, excretion and toxicity (ADMET) of the isolated compounds were examined using admet SAR-2 web server while Swiss ADME was used to analyze the oral bioavailability, drug-likeness and lead-likeness properties of the selected leads. PASS web server was used to predict the biological activities of selected leads while other important physicochemical properties and interactions of the selected leads with the active site of the target after successful molecular docking simulation with the pyrx virtual screening tool were also examined. The results of these study identified seven lead compounds; C49- alpha-carissanol (-7.6 kcal/mol), C13- Catechin (-7.4 kcal/mol), C45- Salicin (-7.4 kcal/mol), C6- Bisnorargemonine (-7.3 kcal/mol), C36- Pallidine (-7.1 kcal/mol), S4- Lacosamide (-7.1 kcal/mol), and S7- Acetazolamide (-6.4 kcal/mol) for CA II (3HS4 receptor). These leads compounds are probable inhibitors of this drug target due to the observed good binding affinities and favourable interactions with the active site of the drug target, excellent ADMET profiles, PASS Properties, drug-likeness, lead-likeness and oral bioavailability properties. The identified leads have better binding energies as compared to the binding energies of the two standards. Thus, seven identified lead compounds can be developed further towards the development of new anti-epileptic medications.

Keywords: drug-likeness, phytochemicals, carbonic anhydrases, metalloeazymes, active site, ADMET

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282 Organic Matter Distribution in Bazhenov Source Rock: Insights from Sequential Extraction and Molecular Geochemistry

Authors: Margarita S. Tikhonova, Alireza Baniasad, Anton G. Kalmykov, Georgy A. Kalmykov, Ralf Littke

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There is a high complexity in the pore structure of organic-rich rocks caused by the combination of inter-particle porosity from inorganic mineral matter and ultrafine intra-particle porosity from both organic matter and clay minerals. Fluids are retained in that pore space, but there are major uncertainties in how and where the fluids are stored and to what extent they are accessible or trapped in 'closed' pores. A large degree of tortuosity may lead to fractionation of organic matter so that the lighter and flexible compounds would diffuse to the reservoir whereas more complicated compounds may be locked in place. Additionally, parts of hydrocarbons could be bound to solid organic matter –kerogen– and mineral matrix during expulsion and migration. Larger compounds can occupy thin channels so that clogging or oil and gas entrapment will occur. Sequential extraction of applying different solvents is a powerful tool to provide more information about the characteristics of trapped organic matter distribution. The Upper Jurassic – Lower Cretaceous Bazhenov shale is one of the most petroliferous source rock extended in West Siberia, Russia. Concerning the variable mineral composition, pore space distribution and thermal maturation, there are high uncertainties in distribution and composition of organic matter in this formation. In order to address this issue geological and geochemical properties of 30 samples including mineral composition (XRD and XRF), structure and texture (thin-section microscopy), organic matter contents, type and thermal maturity (Rock-Eval) as well as molecular composition (GC-FID and GC-MS) of different extracted materials during sequential extraction were considered. Sequential extraction was performed by a Soxhlet apparatus using different solvents, i.e., n-hexane, chloroform and ethanol-benzene (1:1 v:v) first on core plugs and later on pulverized materials. The results indicate that the studied samples are mainly composed of type II kerogen with TOC contents varied from 5 to 25%. The thermal maturity ranged from immature to late oil window. Whereas clay contents decreased with increasing maturity, the amount of silica increased in the studied samples. According to molecular geochemistry, stored hydrocarbons in open and closed pore space reveal different geochemical fingerprints. The results improve our understanding of hydrocarbon expulsion and migration in the organic-rich Bazhenov shale and therefore better estimation of hydrocarbon potential for this formation.

Keywords: Bazhenov formation, bitumen, molecular geochemistry, sequential extraction

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281 12 Real Forensic Caseworks Solved by the DNA STR-Typing of Skeletal Remains Exposed to Extremely Environment Conditions without the Conventional Bone Pulverization Step

Authors: Chiara Della Rocca, Gavino Piras, Andrea Berti, Alessandro Mameli

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DNA identification of human skeletal remains plays a valuable role in the forensic field, especially in missing persons and mass disaster investigations. Hard tissues, such as bones and teeth, represent a very common kind of samples analyzed in forensic laboratories because they are often the only biological materials remaining. However, the major limitation of using these compact samples relies on the extremely time–consuming and labor–intensive treatment of grinding them into powder before proceeding with the conventional DNA purification and extraction step. In this context, a DNA extraction assay called the TBone Ex kit (DNA Chip Research Inc.) was developed to digest bone chips without powdering. Here, we simultaneously analyzed bone and tooth samples that arrived at our police laboratory and belonged to 15 different forensic casework that occurred in Sardinia (Italy). A total of 27 samples were recovered from different scenarios and were exposed to extreme environmental factors, including sunlight, seawater, soil, fauna, vegetation, and high temperature and humidity. The TBone Ex kit was used prior to the EZ2 DNA extraction kit on the EZ2 Connect Fx instrument (Qiagen), and high-quality autosomal and Y-chromosome STRs profiles were obtained for the 80% of the caseworks in an extremely short time frame. This study provides additional support for the use of the TBone Ex kit for digesting bone fragments/whole teeth as an effective alternative to pulverization protocols. We empirically demonstrated the effectiveness of the kit in processing multiple bone samples simultaneously, largely simplifying the DNA extraction procedure and the good yield of recovered DNA for downstream genetic typing in highly compromised forensic real specimens. In conclusion, this study turns out to be extremely useful for forensic laboratories, to which the various actors of the criminal justice system – such as potential jury members, judges, defense attorneys, and prosecutors – required immediate feedback.

Keywords: DNA, skeletal remains, bones, tbone ex kit, extreme conditions

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280 Bifurcations of the Rotations in the Thermocapillary Flows

Authors: V. Batishchev, V. Getman

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We study the self-similar fluid flows in the Marangoni layers with the axial symmetry. Such flows are induced by the radial gradients of the temperatures whose distributions along the free boundary obey some power law. The self-similar solutions describe thermo-capillar flows both in the thin layers and in the case of infinite thickness. We consider both positive and negative temperature gradients. In the former case the cooling of free boundary nearby the axis of symmetry gives rise to the rotation of fluid. The rotating flow concentrates itself inside the Marangoni layer while outside of it the fluid does not revolve. In the latter case we observe no rotating flows at all. In the layers of infinite thickness the separation of the rotating flow creates two zones where the flows are directed oppositely. Both the longitudinal velocity and the temperature have exactly one critical point inside the boundary layer. It is worth to note that the profiles are monotonic in the case of non-swirling flows. We describe the flow outside the boundary layer with the use of self-similar solution of the Euler equations. This flow is slow and non-swirling. The introducing of an outer flow gives rise to the branching of swirling flows from the non-swirling ones. There is such the critical velocity of the outer flow that a non-swirling flow exists for supercritical velocities and cannot be extended to the sub-critical velocities. For the positive temperature gradients there are two non-swirling flows. For the negative temperature gradients the non-swirling flow is unique. We determine the critical velocity of the outer flow for which the branching of the swirling flows happens. In the case of a thin layer confined within free boundaries we show that the cooling of the free boundaries near the axis of symmetry leads to the separating of the layer and creates two sub-layers with opposite rotations inside. This makes sharp contrast with the case of infinite thickness. We show that such rotation arises provided the thickness of the layer exceed some critical value. In the case of a thin layer confined within free and rigid boundaries we construct the branching equation and the asymptotic approximation for the secondary swirling flows near the bifurcation point. It turns out that the bifurcation gives rise to one pair of the secondary swirling flows with different directions of swirl.

Keywords: free surface, rotation, fluid flow, bifurcation, boundary layer, Marangoni layer

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279 Numerical Investigation of Turbulent Flow Control by Suction and Injection on a Subsonic NACA23012 Airfoil by Proper Orthogonal Decomposition Analysis and Perturbed Reynolds Averaged Navier‐Stokes Equations

Authors: Azam Zare

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Separation flow control for performance enhancement over airfoils at high incidence angle has become an increasingly important topic. This work details the characteristics of an efficient feedback control of the turbulent subsonic flow over NACA23012 airfoil using forced reduced‐order model based on the proper orthogonal decomposition/Galerkin projection and perturbation method on the compressible Reynolds Averaged Navier‐Stokes equations. The forced reduced‐order model is used in the optimal control of the turbulent separated flow over a NACA23012 airfoil at Mach number of 0.2, Reynolds number of 5×106, and high incidence angle of 24° using blowing/suction controlling jets. The Spallart-Almaras turbulence model is implemented for high Reynolds number calculations. The main shortcoming of the POD/Galerkin projection on flow equations for controlling purposes is that the blowing/suction controlling jet velocity does not show up explicitly in the resulting reduced order model. Combining perturbation method and POD/Galerkin projection on flow equations introduce a forced reduced‐order model that can predict the time-varying influence of the blowing/suction controlling jet velocity. An optimal control theory based on forced reduced‐order system is used to design a control law for a nonlinear reduced‐order model, which attempts to minimize the vorticity content in the turbulent flow field over NACA23012 airfoil. Numerical simulations were performed to help understand the behavior of the controlled suction jet at 12% to 18% chord from leading edge and a pair of blowing/suction jets at 15% to 18% and 24% to 30% chord from leading edge, respectively. Analysis of streamline profiles indicates that the blowing/suction jets are efficient in removing separation bubbles and increasing the lift coefficient up to 22%, while the perturbation method can predict the flow field in an accurate Manner.

Keywords: flow control, POD, Galerkin projection, separation

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278 Occupational Health Services (OHS) in Hong Kong Hospitals and the Experience of Nurses: A Mixed Methods Study

Authors: Wong Yat Cheung Maggie

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Occupational Safety and Health Ordinance (OS&HO) (Chap 509) was enacted in 1997, OHS in HK should be growing and maturing, with a holistic approach to occupational health and safety in the workplace including physical, mental, social and spiritual well-being. The question is “How effective are OHSPs in meeting the current needs of HK health workers?” This study was designed to explore the issue for the first time, to empirically analyse the views of those who work in the system. The study employed a mixed method approach to collect various data from Occupational Health Service Providers (OHSPs), Occupational Health Service Consumers (OHSC): Registered nurses working in the hospital setting. This study was designed in two phases and two stages. Phase I Stage I was a paper survey to collect the data on OHSP. Then Phase I Stage II was a follow-up interview. Phase II Stage I was a paper survey to collect the data on OHSC. Then Phase II Stage II was a follow-up focus group study on OHSC for further clarification of the Phase II and Stage I result. The Phase I result reflects HK OHSPs point of view and their experience in the existing OHS practice in the local hospitals. It reflects various styles of reporting systems, staff profiles background and resource in providing OHS in HK hospitals. However, the basic OHS concern is similar between hospitals. In general, the OHS policies and procedures are available on site even though they may have different foci. The Phase II result is reflecting the HKs OHSCs echoes the OHSP feedback at providing of OHS, OHS concern and related policies and procedure are available on site. However, the most significant feedback from the OHSC at Phase II Stage II shows, nurses experienced various OHS concern most commonly work stress, workplace harassment and back strain without formal or official report to the related parties. The lack of reporting was due to the management handling attitude, stakeholders’ compliance and term of definition still have room to be improved even the related policies and procedures are available on site.

Keywords: occupational health service, registered nurse, Hong Kong hospital, mixed method

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277 Sensory Characteristics of White Chocolate Enriched with Encapsulated Raspberry Juice

Authors: Ivana Loncarevic, Biljana Pajin, Jovana Petrovic, Danica Zaric, Vesna Tumbas Saponjac, Aleksandar Fistes

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Chocolate is a food that activates pleasure centers in the human brain. In comparison to black and milk chocolate, white chocolate does not contain fat-free cocoa solids and thus lacks bioactive components. The aim of this study was to examine the sensory characteristics of enriched white chocolate with the addition of 10% of raspberry juice encapsulated in maltodextrins (denoted as encapsulate). Chocolate is primarily intended for enjoyment, and therefore, the sensory expectation is a critical factor for consumers when selecting a new type of chocolate. Consumer acceptance of chocolate depends primarily on the appearance and taste, but also very much on the mouthfeel, which mainly depends on the particle size of chocolate. Chocolate samples were evaluated by a panel of 8 trained panelists, food technologists, trained according to ISO 8586 (2012). Panelists developed the list of attributes to be used in this study: intensity of red color (light to dark); glow on the surface (mat to shiny); texture on snap (appearance of cavities or holes on the snap surface that are seen - even to gritty); hardness (hardness felt during the first bite of chocolate sample in half by incisors - soft to hard); melting (the time needed to convert solid chocolate into a liquid state – slowly to quickly); smoothness (perception of evenness of chocolate during melting - very even to very granular); fruitiness (impression of fruity taste - light fruity notes to distinct fruity notes); sweetness (organoleptic characteristic of pure substance or mixture giving sweet taste - lightly sweet to very sweet). The chocolate evaluation was carried out 24 h after sample preparation in the sensory laboratory, in partitioned booths, which were illuminated with fluorescent lights (ISO 8589, 2007). Samples were served in white plastic plates labeled with three-digit codes from a random number table. Panelist scored the perceived intensity of each attribute using a 7-point scale (1 = the least intensity and 7 = the most intensity) (ISO 4121, 2002). The addition of 10% of encapsulate had a big influence on chocolate color, where enriched chocolate got a nice reddish color. At the same time, the enriched chocolate sample had less intensity of gloss on the surface. The panelists noticed that addition of encapsulate reduced the time needed to convert solid chocolate into a liquid state, increasing its hardness. The addition of encapsulate had a significant impact on chocolate flavor. It reduced the sweetness of white chocolate and contributed to the fruity raspberry flavor.

Keywords: white chocolate, encapsulated raspberry juice, color, sensory characteristics

Procedia PDF Downloads 146
276 Scale-Up Study of Gas-Liquid Two Phase Flow in Downcomer

Authors: Jayanth Abishek Subramanian, Ramin Dabirian, Ilias Gavrielatos, Ram Mohan, Ovadia Shoham

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Downcomers are important conduits for multiphase flow transfer from offshore platforms to the seabed. Uncertainty in the predictions of the pressure drop of multiphase flow between platforms is often dominated by the uncertainty associated with the prediction of holdup and pressure drop in the downcomer. The objectives of this study are to conduct experimental and theoretical scale-up study of the downcomer. A 4-in. diameter vertical test section was designed and constructed to study two-phase flow in downcomer. The facility is equipped with baffles for flow area restriction, enabling interchangeable annular slot openings between 30% and 61.7%. Also, state-of-the-art instrumentation, the capacitance Wire-Mesh Sensor (WMS) was utilized to acquire the experimental data. A total of 76 experimental data points were acquired, including falling film under 30% and 61.7% annular slot opening for air-water and air-Conosol C200 oil cases as well as gas carry-under for 30% and 61.7% opening utilizing air-Conosol C200 oil. For all experiments, the parameters such as falling film thickness and velocity, entrained liquid holdup in the core, gas void fraction profiles at the cross-sectional area of the liquid column, the void fraction and the gas carry under were measured. The experimental results indicated that the film thickness and film velocity increase as the flow area reduces. Also, the increase in film velocity increases the gas entrainment process. Furthermore, the results confirmed that the increase of gas entrainment for the same liquid flow rate leads to an increase in the gas carry-under. A power comparison method was developed to enable evaluation of the Lopez (2011) model, which was created for full bore downcomer, with the novel scale-up experiment data acquired from the downcomer with the restricted area for flow. Comparison between the experimental data and the model predictions shows a maximum absolute average discrepancy of 22.9% and 21.8% for the falling film thickness and velocity, respectively; and a maximum absolute average discrepancy of 22.2% for fraction of gas carried with the liquid (oil).

Keywords: two phase flow, falling film, downcomer, wire-mesh sensor

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275 One or More Building Information Modeling Managers in France: The Confusion of the Kind

Authors: S. Blanchard, D. Beladjine, K. Beddiar

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Since 2015, the arrival of BIM in the building sector in France has turned the corporation world upside down. Not only constructive practices have been impacted, but also the uses and the men who have undergone important changes. Thus, the new collaborative mode generated by the BIM and the digital model has challenged the supremacy of some construction actors because the process involves working together taking into account the needs of other contributors. New BIM tools have emerged and actors in the act of building must take ownership of them. It is in this context that under the impetus of a European directive and the French government's encouragement of new missions and job profiles have. Moreover, concurrent engineering requires that each actor can advance at the same time as the others, at the whim of the information that reaches him, and the information he has to transmit. However, in the French legal system around public procurement, things are not planned in this direction. Also, a consequent evolution must take place to adapt to the methodology. The new missions generated by the BIM in France require a good mastery of the tools and the process. Also, to meet the objectives of the BIM approach, it is possible to define a typical job profile around the BIM, adapted to the various sectors concerned. The multitude of job offers using the same terms with very different objectives and the complexity of the proposed missions motivated by our approach. In order to reinforce exchanges with professionals or specialists, we carried out a statistical study to answer this problem. Five topics are discussed around the business area: the BIM in the company, the function (business), software used and BIM missions practiced (39 items). About 1400 professionals were interviewed. These people work in companies (micro businesses, SMEs, and Groups) of construction, engineering offices or, architectural agencies. 77% of respondents have the status of employees. All participants are graduated in their trade, the majority having level 1. Most people have less than a year of experience in BIM, but some have 10 years. The results of our survey help to understand why it is not possible to define a single type of BIM Manager. Indeed, the specificities of the companies are so numerous and complex and the missions so varied, that there is not a single model for a function. On the other hand, it was possible to define 3 main professions around the BIM (Manager, Coordinator and Modeler) and 3 main missions for the BIM Manager (deployment of the method, assistance to project management and management of a project).

Keywords: BIM manager, BIM modeler, BIM coordinator, project management

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274 Petrology of the Post-Collisional Dolerites, Basalts from the Javakheti Highland, South Georgia

Authors: Bezhan Tutberidze

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The Neogene-Quaternary volcanic rocks of the Javakheti Highland are products of post-collisional continental magmatism and are related to divergent and convergent margins of Eurasian-Afroarabian lithospheric plates. The studied area constitutes an integral part of the volcanic province of Central South Georgia. Three cycles of volcanic activity are identified here: 1. Late Miocene-Early Pliocene, 2. Late Pliocene-Early /Middle/ Pleistocene and 3. Late Pleistocene. An intense basic dolerite magmatic activity occurred within the time span of the Late Pliocene and lasted until at least Late /Middle/ Pleistocene. The age of the volcanogenic and volcanogenic-sedimentary formation was dated by geomorphological, paleomagnetic, paleontological and geochronological methods /1.7-1.9 Ma/. The volcanic area of the Javakheti Highland contains multiple dolerite Plateaus: Akhalkalaki, Gomarethi, Dmanisi, and Tsalka. Petrographic observations of these doleritic rocks reveal fairly constant mineralogical composition: olivine / Fo₈₇.₆₋₈₂.₇ /, plagioclase / Ab₂₂.₈ An₇₅.₉ Or₁.₃; Ab₄₅.₀₋₃₂.₃ An₅₂.₉₋₆₂.₃ Or₂.₁₋₅.₄/. The pyroxene is an augite and may exhibit a visible zoning: / Wo 39.7-43.1 En 43.5-45.2 Fs 16.8-11.7/. Opaque minerals /magnetite, titanomagnetite/ is abundant as inclusions within olivine and pyroxene crystals. The texture of dolerites exhibits intergranular, holocrystalline to ophitic to sub ophitic granular. Dolerites are most common vesicular rocks. Vesicles range in shape from spherical to elongated and in size from 0.5 mm to than 1.5-2 cm and makeup about 20-50 % of the volume. The dolerites have been subjected to considerable alteration. The secondary minerals in the geothermal field are: zeolite, calcite, chlorite, aragonite, clay-like mineral /dominated by smectites/ and iddingsite –like mineral; rare quartz and pumpellyite are present. These vesicles are filled by secondary minerals. In the chemistry, dolerites are the calc-alkalic transition to sub-alkaline with a predominance of Na₂O over K₂O. Chemical analyses indicate that dolerites of all plateaus of the Javakheti Highland have similar geochemical compositions, signifying that they were formed from the same magmatic source by crystallization of olivine basalis magma which less differentiated / ⁸⁷Sr \ ⁸⁶Sr 0.703920-0704195/. There is one argument, which is less convincing, according to which the dolerites/basalts of the Javakheti Highland are considered to be an activity of a mantle plume. Unfortunately, there does not exist reliable evidence to prove this. The petrochemical peculiarities and eruption nature of the dolerites of the Javakheti Plateau point against their plume origin. Nevertheless, it is not excluded that they influence the formation of dolerite producing primary basaltic magma.

Keywords: calc-alkalic, dolerite, Georgia, Javakheti Highland

Procedia PDF Downloads 243