Search results for: volumetric mass density
2157 Determination of Direct Solar Radiation Using Atmospheric Physics Models
Authors: Pattra Pukdeekiat, Siriluk Ruangrungrote
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This work was originated to precisely determine direct solar radiation by using atmospheric physics models since the accurate prediction of solar radiation is necessary and useful for solar energy applications including atmospheric research. The possible models and techniques for a calculation of regional direct solar radiation were challenging and compulsory for the case of unavailable instrumental measurement. The investigation was mathematically governed by six astronomical parameters i.e. declination (δ), hour angle (ω), solar time, solar zenith angle (θz), extraterrestrial radiation (Iso) and eccentricity (E0) along with two atmospheric parameters i.e. air mass (mr) and dew point temperature at Bangna meteorological station (13.67° N, 100.61° E) in Bangkok, Thailand. Analyses of five models of solar radiation determination with the assumption of clear sky were applied accompanied by three statistical tests: Mean Bias Difference (MBD), Root Mean Square Difference (RMSD) and Coefficient of determination (R2) in order to validate the accuracy of obtainable results. The calculated direct solar radiation was in a range of 491-505 Watt/m2 with relative percentage error 8.41% for winter and 532-540 Watt/m2 with relative percentage error 4.89% for summer 2014. Additionally, dataset of seven continuous days, representing both seasons were considered with the MBD, RMSD and R2 of -0.08, 0.25, 0.86 and -0.14, 0.35, 3.29, respectively, which belong to Kumar model for winter and CSR model for summer. In summary, the determination of direct solar radiation based on atmospheric models and empirical equations could advantageously provide immediate and reliable values of the solar components for any site in the region without a constraint of actual measurement.Keywords: atmospheric physics models, astronomical parameters, atmospheric parameters, clear sky condition
Procedia PDF Downloads 4092156 Environmental Quality, Dietary Pattern and Nutritional Status of School-Aged Children in Eti-Osa Local Government Area of Lagos State, Nigeria
Authors: Jummai Sekinat Seriki-Mosadolorun, Oyebamiji John Okesoto
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School-aged children in Eti-Osa Local Government Area, Lagos State, were surveyed to determine their food habits, environmental exposures and nutritional status. The method used in this study was a descriptive survey. A systematic questionnaire and anthropometric measurement scales were utilized to compile the data. Information about the children's environment, diets, and demographics were collected using a questionnaire. The children's Body Mass Index (BMI) was calculated using anthropometric measuring scales. The sample size of 400 people was determined by a multi-stage sampling procedure. Chi-square test mean, and Analysis of Variance were used to examine the data. The study's findings suggested that the quality of the children’s natural environments was fairly satisfactory. The youngsters had an unhealthy diet consisting mostly of high-calorie items, including fufu/yam/Eba/pounded yam, biscuits, bread, vegetables, soups, meat, and sweetened drinks. The incidence of malnutrition among school-aged children varied dramatically. The children's environmental quality, eating pattern, and nutritional status were also significantly related to one another (p <0.005). The research came to the conclusion that historic structures should be updated with current technology to promote healthy growth in children, and it suggests that this be done as a matter of strategy.Keywords: environmental quality, dietary pattern, nutritional status, school-aged children., dietary pattern, school-aged children, nutritional status
Procedia PDF Downloads 842155 Quorum-Sensing Driven Inhibitors for Mitigating Microbial Influenced Corrosion
Authors: Asma Lamin, Anna H. Kaksonen, Ivan Cole, Paul White, Xiao-Bo Chen
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Microbiologically influenced corrosion (MIC) is a process in which microorganisms initiate, facilitate, or accelerate the electrochemical corrosion reactions of metallic components. Several reports documented that MIC accounts for about 20 to 40 % of the total cost of corrosion. Biofilm formation due to the presence of microorganisms on the surface of metal components is known to play a vital role in MIC, which can lead to severe consequences in various environmental and industrial settings. Quorum sensing (QS) system plays a major role in regulating biofilm formation and control the expression of some microbial enzymes. QS is a communication mechanism between microorganisms that involves the regulation of gene expression as a response to the microbial cell density within an environment. This process is employed by both Gram-positive and Gram-negative bacteria to regulate different physiological functions. QS involves production, detection, and responses to signalling chemicals, known as auto-inducers. QS controls specific processes important for the microbial community, such as biofilm formation, virulence factor expression, production of secondary metabolites and stress adaptation mechanisms. The use of QS inhibitors (QSIs) has been proposed as a possible solution to biofilm related challenges in many different applications. Although QSIs have demonstrated some strength in tackling biofouling, QSI-based strategies to control microbially influenced corrosion have not been thoroughly investigated. As such, our research aims to target the QS mechanisms as a strategy for mitigating MIC on metal surfaces in engineered systems.Keywords: quorum sensing, quorum quenching, biofilm, biocorrosion
Procedia PDF Downloads 902154 Physicochemical Characterization of Medium Alkyd Resins Prepared with a Mixture of Linum usitatissimum L. and Plukenetia volubilis L. Oils
Authors: Antonella Hadzich, Santiago Flores
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Alkyds have become essential raw materials in the coating and paint industry, due to their low cost, good application properties and lower environmental impact in comparison with petroleum-based polymers. The properties of these oil-modified materials depend on the type of polyunsaturated vegetable oil used for its manufacturing, since a higher degree of unsaturation provides a better crosslinking of the cured paint. Linum usitatissimum L. (flax) oil is widely used to develop alkyd resins due to its high degree of unsaturation. Although it is intended to find non-traditional sources and increase their commercial value, to authors’ best knowledge a natural source that can replace flaxseed oil has not yet been found. However, Plukenetia volubilis L. oil, of Peruvian origin, contains a similar fatty acid polyunsaturated content to the one reported for Linum usitatissimum L. oil. In this perspective, medium alkyd resins were prepared with a mixture of 50% of Linum usitatissimum L. oil and 50% of Plukenetia volubilis L. oil. Pure Linum usitatissimum L. oil was also used for comparison purposes. Three different resins were obtained by varying the amount of glycerol and pentaerythritol. The synthesized alkyd resins were characterized by FT-IR, and physicochemical properties like acid value, colour, viscosity, density and drying time were evaluated by standard methods. The pencil hardness and chemical resistance behaviour of the cured resins were also studied. Overall, it can be concluded that medium alkyd resins containing Plukenetia volubilis L. oil have an equivalent behaviour compared to those prepared purely with Linum usitatissimum L. oil. Both Plukenetia volubilis L. oil and pentaerythritol have a remarkable influence on certain physicochemical properties of medium alkyd resins.Keywords: alkyd resins, flaxseed oil, pentaerythritol, Plukenetia volubilis L. oil, protective coating
Procedia PDF Downloads 1222153 Interaction of Chemical, Microbiological and Ecological Aspects in the Brown Alga Zonaria Tournefortii
Authors: Sonia Hamiche, Naima Bouzidi, Mohamed Reda Zahi, Yasmina Daghbouche, Abdelmalek Badis, Mohamed El Hattab
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This study was carried out on the brown alga Zonaria tourfortii harvested on the central coast of Algeria. The chemical study enabled the characterization of phenolic compounds, mainly acyl phloroglucinol and chromone metabolites. The study isolated a significant quantity of all-cis-5,8,11,14,17 eicosapentanoic acid (EPA). Based on a literature review, we have proposed a biosynthetic pathway leading from EPA to phenolic metabolites. Bacterial screening from the algal surface led to isolate 30 bacterial strains, including 26 Gram+ containing the Staphylococcus and Bacillus genus, and 4 Gram- containing the Acinetobacter and Enterobacteracea genus. In terms of activity profiles, strain S13 (identified as Bacillus amyloliquefaciens based on 16S rRNA technique) proved highly interesting inhibitory activities against target germs, as well as its production of diffusible and volatile compounds. Bacterial cells from the B. amyloliquefaciens S13 strain were used to recover a volatile fraction. Analysis was carried out by gas chromatography-mass spectrometry. The main volatile compounds identified were: 13-epi-manoyl oxide (29.39%), manool (17.39%), 15,16-dinorlabd-8(20)-en-13-one (13.17%), labda-8(17),13Z-dien-15-ol (9. 51%) and 3-acetoxy-13 epimanoyl oxide (5.26%) belonging to the labdane class of diterpenes, the latter having never been described in the category of microbial volatile organic compounds. Ecological aspects were discussed.Keywords: chemical analysis, acylphloroglucinols, phenolic compounds, microbial volatiles, Zonaria tournefortii
Procedia PDF Downloads 602152 The Information-Seeking Behaviour of Kuwaiti Judges (KJs)
Authors: Essam Mansour
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The key purpose of this study is to show information-seeking behaviour of Kuwaiti Judges (KJs). Being one of the few studies about the information needs and information-seeking behaviour conducted in Arab and developing countries, this study is a pioneer one among many studies conducted in information seeking, especially with this significant group of information users. The authors tried to investigate this seeking behavior in terms of KJs' thoughts, perceptions, motivations, techniques, preferences, tools and barriers met when seeking information. The authors employed a questionnaire, with a response rate 77.2 percent. This study showed that most of KJs were likely to be older, educated and with a work experience ranged from new to old experience. There is a statistically reliable significant difference between KJs' demographic characteristics and some sources of information, such as books, encyclopedias, references and mass media. KJs were using information moderately to make a decision, to be in line with current events, to collect statistics and to make a specific/general research. The office and home were the most frequent location KJs were accessing information from. KJs' efficiency level of the English language is described to be moderately good, and a little number of them confirmed that their efficiency level of French was not bad. The assistance provided by colleagues, followed by consultants, translators, sectaries and librarians were found to be most strong types of assistance needed when seeking information. Mobile apps, followed by PCs, information networks (the Internet) and information databases were the highest technology tool used by KJs. Printed materials, followed by non-printed and audiovisual materials were the most preferred information formats KJs use. The use of languages, the recency of information and the place of information, the deficit role of the library to deliver information were at least significant barriers to KJs when seeking information.Keywords: information users, information-seeking behaviour, information needs, judges, Kuwait
Procedia PDF Downloads 3072151 High Pressure Delignification Process for Nanocrystalline Cellulose Production from Agro-Waste Biomass
Authors: Sakinul Islam, Nhol Kao, Sati Bhattacharya, Rahul Gupta
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Nanocrystalline cellulose (NCC) has been widely used for miscellaneous applications due to its superior properties over other nanomaterials. However, the major problems associated with the production of NCC are long reaction time, low production rate and inefficient process. The mass production of NCC within a short period of time is still a great challenge. The main objective of this study is to produce NCC from rice husk agro waste biomass from a high pressure delignification process (HPDP), followed by bleaching and hydrolysis processes. The HPDP has not been explored for NCC production from rice husk biomass (RHB) until now. In order to produce NCC, powder rice husk (PRH) was placed into a stainless steel reactor at 80 ˚C under 5 bars. Aqueous solution of NaOH (4M) was used for the dissolution of lignin and other amorphous impurities from PRH. After certain experimental times (1h, 3.5h and 6h), bleaching and hydrolysis were carried out on delignified samples. NaOCl (20%) and H2SO4 (4M) solutions were used for bleaching and hydrolysis processes, respectively. The NCC suspension from hydrolysis was sonicated and neutralized by buffer solution for various characterisations. Finally NCC suspension was dried and analyzed by FTIR, XRD, SEM, AFM and TEM. The chemical composition of NCC and PRH was estimated by TAPPI (Technical Association of Pulp and Paper Industry) standard methods to observe the product purity. It was found that, the 6h of the HPDP was more efficient to produce good quality NCC than that at 1h and 3.5h due to low separation of non-cellulosic components from RHB. The analyses indicated the crystallinity of NCC to be 71 %, particle size of 20-50 nm (diameter) and 100-200 nm in length.Keywords: nanocrystalline cellulose, NCC, high pressure delignification, bleaching, hydrolysis, agro-waste biomass
Procedia PDF Downloads 2642150 General Evaluation of a Three-Year Holistic Physical Activity Interventions Program in Qatar Campuses: Step into Health (SIH) in Campuses 2013- 2016
Authors: Daniela Salih Khidir, Mohamed G. Al Kuwari, Mercia V. Walt, Izzeldin J. Ibrahim
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Background: University-based physical activity interventions aim to establish durable social patterns during the transition to adulthood. This study is a comprehensive evaluation of a 3-year intervention-based program to increase the culture of physical activity (PA) routine in Qatar campuses community, using a holistic approach. Methodology: General assessment methods: formative evaluation-SIH Campuses logic model design, stakeholders’ identification; process evaluation-members’ step counts analyze and qualitative Appreciative Inquiry session (4-D model); daily steps categorized as: ≤5,000, inactive; 5,000-7,499 low active; ≥7,500, physically active; outcome evaluation - records 3 years interventions. Holistic PA interventions methods: walking interventions - pedometers distributions and walking competitions for students and staff; educational interventions - in campuses implementation of bilingual educational materials, lectures, video related to PA in prevention of non-communicable diseases (NCD); articles published online; monthly emails and sms notifications for pedometer use; mass media campaign - radio advertising, yearly pre/post press releases; community stakeholders interventions-biyearly planning/reporting/achievements rewarding/ qualitative meetings; continuous follow-up communication, biweekly steps reports. Findings: Results formative evaluation - SIH in Campuses logic model identified the need of PA awareness and education within universities, resources, activities, health benefits, program continuity. Results process evaluation: walking interventions: Phase 1: 5 universities recruited, 2352 members, 3 months competition; Phase 2: 6 new universities recruited, 1328 members in addition, 4 months competition; Phase 3: 4 new universities recruited in addition, 1210 members, 6 months competition. Results phase 1 and 2: 1,299 members eligible for analyzes: 800 females (62%), 499 males (38%); 86% non-Qataris, 14% Qatari nationals, daily step count 5,681 steps, age groups 18–24 (n=841; 68%) students, 25–64; (n=458; 35.3%) staff; 38% - low active, 37% physically active and 25% inactive. The AI main themes engaging stakeholders: awareness/education - 5 points (100%); competition, multi levels of involvement in SIH, community-based program/motivation - 4 points each (80%). The AI points represent themes’ repetition within stakeholders’ discussions. Results education interventions: 2 videos implementation, 35 000 educational materials, 3 online articles, 11 walking benefits lectures, 40 emails and sms notifications. Results community stakeholders’ interventions: 6 stakeholders meetings, 3 rewarding gatherings, 1 focus meeting, 40 individual reports, 18 overall reports. Results mass media campaign: 1 radio campaign, 7 press releases, 52 campuses newsletters. Results outcome evaluation: overall 2013-2016, the study used: 1 logic model, 3 PA holistic interventions, partnerships 15 universities, registered 4890 students and staff (aged 18-64 years), engaged 30 campuses stakeholders and 14 internal stakeholders; Total registered population: 61.5% female (2999), 38.5% male (1891), 20.2% (988) Qatari nationals, 79.8% (3902) non-Qataris, 55.5% (2710) students aged 18 – 25 years, 44.5% (2180) staff aged 26 - 64 years. Overall campaign 1,558 members eligible for analyzes: daily step count 7,923; 37% - low active, 43% physically active and 20% inactive. Conclusion: The study outcomes confirm program effectiveness and engagement of young campuses community, specifically female, in PA. The authors recommend implementations of 'holistic PA intervention program approach in Qatar' aiming to impact the community at national level for PA guidelines achievement in support of NCD prevention.Keywords: campuses, evaluation, Qatar, step-count
Procedia PDF Downloads 3102149 Pedagogy to Involve Research Process in an Undergraduate Physical Fitness Course: A Case Study
Authors: Indhumathi Gopal
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Undergraduate research is well documented in Science, Technology, Engineering, and Mathematics (STEM), neurosciences, and microbiology disciplines, though it is hardly part of a physical fitness & wellness discipline. However, students need experiential learning opportunities, like internships and research assistantships, to get ahead with graduate schools and be gainfully employed. The first step towards this goal is to have students do a simple research project in a semester-long course. The value of research experiences and how to integrate research activity in a physical fitness & wellness course are discussed. The investigator looks into a mini research project, “Awareness of Obesity among College Students” and explains how to guide students through the research process, including journal search, data collection, and basic statistics. Besides, students will be introduced to the statistical package program SPSS 22.0 to assist with data evaluation. The lab component of the combined lecture-physical activity course could include the measurement of student’s weight with respect to their height to obtain body mass index (BMI). Students could categorize themselves in accordance with the World Health Organization’s guidelines. Results obtained after completing the data analysis help students be aware of their own potential health risks associated with overweight and obesity. Overweight and obesity are risk factors for hypertension, hypercholesterolemia, heart disease, stroke, diabetes, and certain types of cancer. It is hoped that this experience will get students interested in scientific studies, gain confidence, think critically, and develop problem-solving and good communication skills.Keywords: physical fitness, undergraduate research experience, obesity, BMI
Procedia PDF Downloads 812148 The Effect of Pozzolan Addition on the Physico-Chemical and Mechanical Properties of Mortars Based on Cement Resistant to Sulfate (CRS)
Authors: L. Belagraa, A. Belguendouz, Y. Rouabah, A. Bouzid, A. Noui, O. Kessal
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The use of cements CRS in aggressive environments showed a lot of benefits as like good mechanical responses and therefore better durability, however, their manufacturing consume a lot of clinker, which leads to the random hazardous deposits, the shortage of natural resources and the gas and the dust emissions mainly; (CO2) with its ecological negative impact on the environment. Technical, economic and environmental benefits by the use of blended cements have been reported and being considered as a research area of great interest. The purpose of this study is to evaluate the influence of the substitution of natural pozzolan on the physico-chemical properties of the new formulated binder and the mechanical behavior of mortar containing this binary cement. Hence, the pozzolan replacement is composed with different proportions (0%, 2.5%, 5%, 7.5% and 10%). The physico-chemical properties of cement resistant to sulfate (CRS) alternative composition were investigated. Further, the behavior of the mortars based on this binder is studied. These characteristics includes chemical composition, density and fineness, consistency, setting time, shrinkage, absorption and the mechanical response. The results obtained showed that the substitution of pozzolan at the optimal ratio of 5% has a positive effect on the resulting cement, greater specific surface area, reduced water demand, accelerating the process of hydration, a better mechanical responses and decreased absorption. Therefore, economic and ecological cement based on mineral addition like pozzolan could be possible as well as advantageous to the formulation of environmental mortars.Keywords: Cement Resistant to Sulfate (CRS), environmental mortars mechanical response, physico-chemical properties, pozzolan
Procedia PDF Downloads 3612147 Deep Foundations: Analysis of the Lateral Response of Closed Ended Steel Tubular Piles Embedded in Sandy Soil Using P-Y Curves
Authors: Ameer A. Jebur, William Atherton, Rafid M. Alkhaddar, Edward Loffill
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Understanding the behaviour of the piles under the action of the independent lateral loads and the precise prediction of the capacity of piles subjected to different lateral loads are vital topics in foundation design and analysis. Moreover, the laterally loaded behaviour of deep foundations penetrated in cohesive and non-cohesive soils is basically analysed by the Winkler Model (beam on elastic foundation), in which the interaction between the pile embedded depth and contacted soil is simulated by nonlinear p–y curves. The presence of many approaches to interpret the behaviour of soil-pile interaction has resulted in numerous outputs and indicates that no general approach has yet been adopted. The current study presents the result of numerical modelling of the behaviour of steel tubular piles (25.4mm) outside diameter with various embedment depth-to-diameter ratios (L/d) embedded in a sand calibrated chamber of known relative density. The study revealed that the shear strength parameters of the sand specimens and the (L/d) ratios are the most significant factor influencing the response of the pile and its capacity while taking into consideration the complex interaction between the pile and soil. Good agreement has been achieved when comparing the application of this modelling approach with experimental physical modelling carried out by another researcher.Keywords: deep foundations, slenderness ratio, soil-pile interaction, winkler model (beam on elastic foundation), non-cohesive soil
Procedia PDF Downloads 2992146 Effect of Fermentation Time on Some Functional Properties of Moringa (Moringa oleifera) Seed Flour
Authors: Ocheme B. Ocheme, Omobolanle O. Oloyede, S. James, Eleojo V. Akpa
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The effect of fermentation time on some functional properties of Moringa (Moringa oleifera) seed flour was examined. Fermentation, an effective processing method used to improve nutritional quality of plant foods, tends to affect the characteristics of food components and their behaviour in food systems just like other processing methods. Hence the need for this study. Moringa seeds were fermented naturally by soaking in potable water and allowing it to stand for 12, 24, 48 and 72 hours. At the end of fermentation, the seeds were oven dried at 600C for 12 hours and then milled into flour. Flour obtained from unfermented seeds served as control: hence a total of five flour samples. The functional properties were analyzed using standard methods. Fermentation significantly (p<0.05) increased the water holding capacity of Moringa seed flour from 0.86g/g - 2.31g/g. The highest value was observed after 48 hours of fermentation The same trend was observed for oil absorption capacity with values between 0.87 and 1.91g/g. Flour from unfermented Moringa seeds had a bulk density of 0.60g/cm3 which was significantly (p<0.05) higher than the bulk densities of flours from seeds fermented for 12, 24 and 48. Fermentation significantly (p<0.05) decreased the dispersibility of Moringa seed flours from 36% to 21, 24, 29 and 20% after 12, 24, 48 and 72 hours of fermentation respectively. The flours’ emulsifying capacities increased significantly (p<0.05) with increasing fermentation time with values between 50 – 68%. The flour obtained from seeds fermented for 12 hours had a significantly (p<0.05) higher foaming capacity of 16% while the flour obtained from seeds fermented for 0, 24 and 72 hours had the least foaming capacities of 9%. Flours from seeds fermented for 12 and 48 hours had better functional properties than flours from seeds fermented for 24 and 72 hours.Keywords: fermentation, flour, functional properties, Moringa
Procedia PDF Downloads 6882145 Wireworms under the Sword of Damocles: Attraction to Maize Root Volatiles
Authors: Diana La Forgia, Jean Baptiste Thibord, François Verheggen
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Volatiles Organic Compound (VOCs) are one of the many features of defense used by plants in their eternal fight against pests. Their main role is to attract the natural enemies of the herbivores. But on another hand, they can be used by the same herbivores to locate plants while foraging. In an attempt to fill a gap of knowledge in a complex web of interactions, we focused on wireworms (Coleoptera:Elateridae). Wireworms whose larvae feed on roots are one of the most spread pests of valuable crops such as maize and potatoes, causing important economical damage. Little is known about the root compounds that are playing a role in the attraction of the larvae. In order to know more about these compounds, we compared four different maize varieties (Zea mays mays) that are known to have different levels of attraction, from weak to strong, for wireworms in fields. We tested the attraction of larvae in laboratory conditions in dual-choice olfactometer assays where they were offered all possible combinations of the four maize varieties. Contemporary, we collected the VOCs of each variety during 24h using a push-and-pull system. The collected samples were then analyzed by gas chromatography coupled with a mass spectrometer (GC-MS) to identify their molecular profiles. The choice of the larvae was dependent on the offered combination and some varieties were preferred to others. Differences were also observed in terms of quantitative and qualitative emissions of volatile profiles between the maize varieties. Our aim is to develop traps based on VOCs from maize roots to open a new frontier in wireworms management.Keywords: integrated pest management, maize roots, plant defense, volatile organic compounds, wireworms
Procedia PDF Downloads 1552144 Study on the Spatial Vitality of Waterfront Rail Transit Station Area: A Case Study of Main Urban Area in Chongqing
Authors: Lianxue Shi
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Urban waterfront rail transit stations exert a dual impact on both the waterfront and the transit station, resulting in a concentration of development elements in the surrounding space. In order to more effectively develop the space around the station, this study focuses on the perspective of the integration of station, city, and people. Taking Chongqing as an example, based on the Arc GIS platform, it explores the vitality of the site from the three dimensions of crowd activity heat, space facilities heat, and spatial accessibility. It conducts a comprehensive evaluation and interpretation of the vitality surrounding the waterfront rail transit station area in Chongqing. The study found that (1) the spatial vitality in the vicinity of waterfront rail transit stations is correlated with the waterfront's functional zoning and the intensity of development. Stations situated in waterfront residential and public spaces are more likely to experience a convergence of people, whereas those located in waterfront industrial areas exhibit lower levels of vitality. (2) Effective transportation accessibility plays a pivotal role in maintaining a steady flow of passengers and facilitating their movement. However, the three-dimensionality of urban space in mountainous regions is a notable challenge, leading to some stations experiencing limited accessibility. This underscores the importance of enhancing the optimization of walking space, particularly the access routes from the station to the waterfront area. (3) The density of spatial facilities around waterfront stations in old urban areas lags behind the population's needs, indicating a need to strengthen the allocation of relevant land and resources in these areas.Keywords: rail transit station, waterfront, influence area, spatial vitality, urban vitality
Procedia PDF Downloads 312143 Investigation on Scattered Dose Rate and Exposure Parameters during Diagnostic Examination Done with an Overcouch X-Ray Tube in Nigerian Teaching Hospital
Authors: Gbenga Martins, Christopher J. Olowookere, Lateef Bamidele, Kehinde O. Olatunji
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The aims of this research are to measure the scattered dose rate during an X-ray examination in an X-ray room, compare the scattered dose rate with exposure parameters based on the body region examined, and examine the X-ray examination done with an over couch tube. The research was carried out using Gamma Scout software installation on the computer system (Laptop) to record the radiation counts, pulse rate, and dose rate. The measurement was employed by placing the detector at 900 to the incident X-ray. Proforma was used for the collection of patients’ data such as age, sex, examination type, and initial diagnosis. Data such as focus skin distance (FSD), body mass index (BMI), body thickness of the patients, the beam output (kVp) were collected at Obafemi Awolowo University, Ile-Ife, Western Nigeria. Total number of 136 patients was considered during this research. Dose rate range between 14.21 and 86.78 µSv/h for the plain abdominal region, 85.70 and 2.86 µSv/h for the lumbosacral region,1.3 µSv/yr and 3.6 µSv/yr in the pelvis region, 2.71 µSv/yr and 28.88 µSv/yr for leg region, 3.06 µSv/yr and 29.98 µSv/yr in hand region. The results of this study were compared with those of other studies carried out in other countries. The findings of this study indicated that the number of exposure parameters selected for each diagnostic examination contributed to the dose rate recorded. Therefore, these results call for a quality assurance program (QAP) in diagnostic X-ray units in Nigerian hospitals.Keywords: X-radiation, exposure parameters, dose rate, pulse rate, number of counts, tube current, tube potential, diagnostic examination, scattered radiation
Procedia PDF Downloads 1162142 An Assessment of the Anthropometric Characteristics of Malaysian Cricket Batsmen
Authors: Muhammad Zia ul Haq, Ong Kuan Boon, Jeffrey Low Fook Lee, Bendri Bin Dasril, Amna Iqbal, Muhammad Saleem
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This study is bond of two purpose, first is to establish the anthropometric profile of Malaysian cricket batsmen and second, to find the variances among the anthropometric characteristics of ten under-16 years, eight under-19 years and eight senior teams batsmen. The anthropometric variables were measured as 8 skinfolds, 12 circumferences, 06 lengths and 05 breadths, stature, sitting height, arm span, body mass, hand grip strength and leg strength. The batsmen of under-19 and under-16 found similar in skinfolds, sum of skinfolds, circumferences and breadth measurements but significantly lesser than the senior team batsmen. Senior and Under-19 batsmen were almost found similar in segmental lengths, heights and arm span but significantly higher than the under-16 batsmen. Breadth measurements the under-19 found higher than the senior and u-16 batsmen. The hand grips strength of the senior batsmen significantly high than the uder-19 and under-16 players and both groups were similar and no significant difference were found in leg strength of all three groups batsmen. Leg strength were found significant correlation with wrist, hip, thigh, and calf girth and handgrip strength. The hand grip strength were found correlated with all variables except biceps, mid-thigh skinfold, segmental length, humerus breadth. It is concluded from the present study that the girth segments and hand grip strength are the predictors of good performance in cricket batting.Keywords: cricket batting, batsmen, anthropometry, body segments, hand grip strength
Procedia PDF Downloads 5752141 A Molecular Dynamics Study on Intermittent Plasticity and Dislocation Avalanche Emissions in FCC and BCC Crystals
Authors: Javier Varillas, Jorge Alcalá
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We investigate dislocation avalanche phenomena in face-centered cubic (FCC) and body-centered cubic (BCC) crystals using massive, large-scale molecular dynamics (MD) simulations. The analysis is focused on the intermittent development of dense dislocation arrangements subjected to uniaxial tensile straining under displacement control. We employ a novel computational scheme that allows us to inject an entangled dislocation structure in periodic MD domains. We assess the emission of plastic bursts (or dislocation avalanches) in terms of the sharp stress drops detected in the stress-strain curve. The plastic activity corresponds to the sporadic operation of specific dislocation glide processes exhibiting quiescent periods between successive avalanche events. We find that the plastic intermittences in our simulations do not overlap in time under sufficiently low strain rates as dissipation operates faster than driving, where the dense dislocation networks evolve through the emission of dislocation avalanche events whose carried slip adheres to self-organized power-law distributions. These findings enable the extension of the slip distributions obtained from strict displacement-controlled micropillar compression experiments towards smaller values of slip size. Our results furnish further understanding upon the development of entangled dislocation networks in metal plasticity, including specific mechanisms of dislocation propagation and annihilation, along with the evolution of specific dislocation populations through dislocation density analyses.Keywords: dislocations, intermittent plasticity, molecular dynamics, slip distributions
Procedia PDF Downloads 1392140 Probabilistic Approach to the Spatial Identification of the Environmental Sources behind Mortality Rates in Europe
Authors: Alina Svechkina, Boris A. Portnov
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In line with a rapid increase in pollution sources and enforcement of stricter air pollution regulation, which lowers pollution levels, it becomes more difficult to identify actual risk sources behind the observed morbidity patterns, and new approaches are required to identify potential risks and take preventive actions. In the present study, we discuss a probabilistic approach to the spatial identification of a priori unidentified environmental health hazards. The underlying assumption behind the tested approach is that the observed adverse health patterns (morbidity, mortality) can become a source of information on the geographic location of environmental risk factors that stand behind them. Using this approach, we analyzed sources of environmental exposure using data on mortality rates available for the year 2015 for NUTS 3 (Nomenclature of Territorial Units for Statistics) subdivisions of the European Union. We identified several areas in the southwestern part of Europe as primary risk sources for the observed mortality patterns. Multivariate regressions, controlled by geographical location, climate conditions, GDP (gross domestic product) per capita, dependency ratios, population density, and the level of road freight revealed that mortality rates decline as a function of distance from the identified hazard location. We recommend the proposed approach an exploratory analysis tool for initial investigation of regional patterns of population morbidity patterns and factors behind it.Keywords: mortality, environmental hazards, air pollution, distance decay gradient, multi regression analysis, Europe, NUTS3
Procedia PDF Downloads 1672139 Effects of Monofin Training on Left Ventricular Performance in Elite Egyptian Children Athletes
Authors: Magdy Abouzeid
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Objectives: The aim of this study was to examine the influence of Monofin training, 36 weeks, 6 times per week, 90 min/unit on left ventricular performance in elite Egyptian Monofin athletes. Background: The elite athletes are one who has superior athletic talent. Monofin swimming already provide the most efficient way of swimming for human being, it is an aquatics sport practice on the surface or under water. Methods :To study these effects,14 elite Monofin children(3 girls and 11boys) aged(11.95± 1.09yr) HT (153.07± 4.2 cm) , WT(52.4 ± 3.7 kg ) , body surface area (BSA.m2 1.48 ± 5.6 m2 ) took part in long-term Monofin Training(LTMT).All subjects underwent two-dimension and M-mode Echordiography at rest before and after(LTMT). Results: There was significant difference (P < 0.01) and percentage improvement for all echocardiography parameter after (LTMT). Inter ventricular septal thickness in diastole and in systole increased by 27.9 % and 42.75 %. Left ventricular end systolic dimension and diastole increased by 16.81 % and 42.7 % respectively. Posterior wall thickness in systole was very highly increased by 283.3 % and in diastole increased by 51.78 %. Left ventricular mass in diastole and in systole increased by 44.8 % and 40.1 % respectively. Stroke volume and resting heart rate (HR) significant changed (sv) 25 %, (HR) 14.7 %. Conclusion: Monofin training is an effective sport to enhance ‘Heart athlete's’ for children, because the unique swim fin tool and create propulsion and overcome resistance. Further researches are needed to determine the effects of Monofin training on right ventricular in child athletes.Keywords: prepubertal, monofin training, heart athlete's, elite child athlete, echocardiography
Procedia PDF Downloads 3152138 Resistin Mediates Tomato and Broccoli Extracts Effects on Glucose Homeostasis in High Fat Diet Induced Obesity in Rats
Authors: N. M. Aborehab, M. Helmy, N. E. Waly
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Resistin was identified as an adipocyte hormone that participates in regulation of glucose metabolism. Elevated levels of Resistin are postulated to cause insulin resistance. This may link obesity, and increased fat mass to type II diabetes and insulin resistance. We hypothesized that tomato and broccoli extract treatment regulates glucose homeostasis via modulation of resistin levels in high fat diet induced obesity rats (HFD). 63 male albino rats were divided into 8 groups as follows: control, HFD, stop fat diet (SD), Tomato 200 mg/kg (T200), Tomato 400mg/kg (T400), Broccoli 200 mg/kg (B200), Broccoli 400 mg/kg (B400), Chromax (CX). Treatment continued for 1 month. Serum levels of resistin, leptin, adiponectin, glucose and insulin were measured using ELISA, and spectrophotometry. Serum level of resistin was significantly reduced in T 200, T 400, B 200, B 400 and CX groups to: 4.13 ± 0.22 ng/ml, 1.51 ± 0.04 ng/ml, 4.13 ± 0.22 ng/ml, 2.32 ± 0.15 ng/ml and 1.37 ± 0.03 ng/ml respectively compared to HFD group and SD group (P value < 0.0001). Non-significant difference was found between T 400, B 400 and CX groups. Mean serum level of leptin was significantly reduced in T 400 (22.7 ± 0.84 Pg/ml) group compared to B 400 (41 ± 2.45 Pg/ml) and CX groups (45.7 ± 2.91 Pg/ml), P value < 0.001.The mean serum level of adiponectin was significantly increased in T 400 group (131 ± 3.84 Pg/ml) compared to CX group (112 ± 4.77 Pg/ml), P value was < 0.01. Our results demonstrate that tomato and broccoli extract treatment regulates glucose homeostasis via reduction of serum resistin and may be a useful non-pharmacological therapy for obesity. Further studies are required to assess the potential use of these extract as a treatment for type II diabetes and obesity.Keywords: broccoli, obesity, resistin, tomato
Procedia PDF Downloads 3012137 Wind Resource Estimation and Economic Analysis for Rakiraki, Fiji
Authors: Kaushal Kishore
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Immense amount of imported fuels are used in Fiji for electricity generation, transportation and for carrying out miscellaneous household work. To alleviate its dependency on fossil fuel, paramount importance has been given to instigate the utilization of renewable energy sources for power generation and to reduce the environmental dilapidation. Amongst the many renewable energy sources, wind has been considered as one of the best identified renewable sources that are comprehensively available in Fiji. In this study the wind resource assessment for three locations in Rakiraki, Fiji has been carried out. The wind resource estimation at Rokavukavu, Navolau and at Tuvavatu has been analyzed. The average wind speed at 55 m above ground level (a.g.l) at Rokavukavu, Navolau, and Tuvavatu sites are 5.91 m/s, 8.94 m/s and 8.13 m/s with the turbulence intensity of 14.9%, 17.1%, and 11.7% respectively. The moment fitting method has been used to estimate the Weibull parameter and the power density at each sites. A high resolution wind resource map for the three locations has been developed by using Wind Atlas Analysis and Application Program (WAsP). The results obtained from WAsP exhibited good wind potential at Navolau and Tuvavatu sites. A wind farm has been proposed at Navolau and Tuvavatu site that comprises six Vergnet 275 kW wind turbines at each site. The annual energy production (AEP) for each wind farm is estimated and an economic analysis is performed. The economic analysis for the proposed wind farms at Navolau and Tuvavatu sites showed a payback period of 5 and 6 years respectively.Keywords: annual energy production, Rakiraki Fiji, turbulence intensity, Weibull parameter, wind speed, Wind Atlas Analysis and Application Program
Procedia PDF Downloads 1882136 Investigating Dynamic Transition Process of Issues Using Unstructured Text Analysis
Authors: Myungsu Lim, William Xiu Shun Wong, Yoonjin Hyun, Chen Liu, Seongi Choi, Dasom Kim, Namgyu Kim
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The amount of real-time data generated through various mass media has been increasing rapidly. In this study, we had performed topic analysis by using the unstructured text data that is distributed through news article. As one of the most prevalent applications of topic analysis, the issue tracking technique investigates the changes of the social issues that identified through topic analysis. Currently, traditional issue tracking is conducted by identifying the main topics of documents that cover an entire period at the same time and analyzing the occurrence of each topic by the period of occurrence. However, this traditional issue tracking approach has limitation that it cannot discover dynamic mutation process of complex social issues. The purpose of this study is to overcome the limitations of the existing issue tracking method. We first derived core issues of each period, and then discover the dynamic mutation process of various issues. In this study, we further analyze the mutation process from the perspective of the issues categories, in order to figure out the pattern of issue flow, including the frequency and reliability of the pattern. In other words, this study allows us to understand the components of the complex issues by tracking the dynamic history of issues. This methodology can facilitate a clearer understanding of complex social phenomena by providing mutation history and related category information of the phenomena.Keywords: Data Mining, Issue Tracking, Text Mining, topic Analysis, topic Detection, Trend Detection
Procedia PDF Downloads 4082135 Anti-Melanogenesis and Anti-Inflammatory Effects of Opuntia humifusa
Authors: Yonghwa Lee, Yoon Suk Kim, Yongsub Yi
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This study was to confirm the effects of anti-melanogenesis and anti-inflammatory effects from Opuntia humifusa fruit and stem extracts. A potent anti-oxidant activity was shown from the leaf extract at IC50 value of 38.33±1.07 μg/mL and fruit extract at IC50 value of 40.23±2.21 μg/mL by 1,1-diphenyl-2-picrylhydrazyl (DPPH) assay. Also, phenolic contents were confirmed total phenolic assay by high performance liquid chromatography (HPLC). Fraction of taxifolin from leaf extract was identified using HPLC and gas chromatography/mass spectrometry. The extracts of Opuntia humifusa fruit and stem were confirmed about toxicity effect in B16 F1 by cell viability. Melanin contents were decreased. Opuntia humifusa fruit and stem extracts had a positive effect of melanin synthesis inhibition for skin whitening. In investigating the anti-inflammatory activities of Opuntia humifusa, the results of cell viability indicated that taxifolin did not show cytotoxicity on RAW264.7 cells at 500 μM of concentration. The results show that taxifolin inhibited lipopolysaccharide (LPS)-induced production of Nitrite oxide (NO). In addition, taxifolin indicated the inhibition of lipopolysaccharide (LPS)-induced tumor necrosis factor (TNF) -α and interleukin (IL) -6 productions by cytokine assay and cyclooxygenase (COX)-2 expression by western blot analysis, meaning that taxifolin had a significant anti-inflammatory effect. Our results suggested that taxifolin from Opuntia humifusa has anti-melanogenesis and anti-inflammatory activities.Keywords: anti-melanogenesis, anti-inflammatory, Opuntia humifusa, taxifolin
Procedia PDF Downloads 3132134 Metabolome-based Profiling of African Baobab Fruit (Adansonia Digitata L.) Using a Multiplex Approach of MS and NMR Techniques in Relation to Its Biological Activity
Authors: Marwa T. Badawy, Alaa F. Bakr, Nesrine Hegazi, Mohamed A. Farag, Ahmed Abdellatif
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Diabetes Mellitus (DM) is a chronic disease affecting a large population worldwide. Africa is rich in native medicinal plants with myriad health benefits, though less explored towards the development of specific drug therapy as in diabetes. This study aims to determine the in vivo antidiabetic potential of the well-reported and traditionally used fruits of Baobab (Adansonia digitata L.) using STZ induced diabetic model. The in-vitro cytotoxic and antioxidant properties were examined using MTT assay on L-929 fibroblast cells and DPPH antioxidant assays, respectively. The extract showed minimal cytotoxicity with an IC50 value of 105.7 µg/mL. Histopathological and immunohistochemical investigations showed the hepatoprotective and the renoprotective effects of A. digitata fruits’ extract, implying its protective effects against diabetes complications. These findings were further supported by biochemical assays, which showed that i.p., injection of a low dose (150 mg/kg) of A. digitata twice a week lowered the fasting blood glucose levels, lipid profile, hepatic and renal markers. For a comprehensive overview of extract metabolites composition, ultrahigh performance (UHPLC) analysis coupled to high-resolution tandem mass spectrometry (HRMS/MS) in synchronization with molecular networks led to the annotation of 77 metabolites, among which 50% are reported for the first time in A. digitata fruits.Keywords: adansonia digital, diabetes mellitus, metabolomics, streptozotocin, Sprague, dawley rats
Procedia PDF Downloads 1642133 The Influence of Viscosifier Concentration on Rheological Properties of Invert Emulsion Mud
Authors: Suzan Ibrahim
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Oil-based muds are the most regularly used rotary drilling methods in the oil and gas industry. However, they have a negative impact on the environment, which leads to restrictions of their application in many countries of the world. Consequently, looking for new eco-friendly alternative formulations of oil-based drilling fluids for the exploration of troublesome formations. As one of the developments of Novel formulation of environmentally friendly drilling fluids and investigation of the formulation for jatropha oil-based drilling fluid samples at different concentrations of viscosifiers such as low viscosity polyanionic cellulose (PAC- LV), high viscosity polyanionic cellulose (PAC-V) and local Egyptian bentonite. The oil-water ratio was taken as 70:30, which is beneficial in producing a low fluid loss. 15 drilling fluid samples were formulated different concentrations of bentonite, PAC- LV and PAC-V individually and their mud density, rheological properties, electrical stability and filtration loss properties were determined. The rheological performance showed at higher concentrations of viscosifier, the trend of viscosity increment of PAC performed in a similar way to bentonite. The best result of electrical stability by using the lowest concentration of viscosifier was achieved with PAC-V. The lowest fluid loss volumes were obtained by using the highest concentrations (4 g) of viscosifiers. Mud cake thickness of samples increased by using viscosifiers; however, a lower range was achieved compared to API specification. From the overall experiment, it can be concluded that as the concentrations of viscosifier increase, the viscosity trend increase in a similar way to both PAC-V and bentonite. But we must note that the PAC-V is a more environmentally friendly additive and a renewable resource, cheaper than bentonite and improves properties of eco-friendly OBMs well. It is a preferable choice for oil-based drilling fluids.Keywords: invert emulsion mud, oil-based mud, rheological properties, viscosifier
Procedia PDF Downloads 1702132 Simulative Study of the Influence of Degraded Twin-Tube Shock Absorbers on the Lateral Forces of Vehicle Axles
Authors: Tobias Schramm, Günther Prokop
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Degraded vehicle shock absorbers represent a risk for road safety. The exact effect of degraded vehicle dampers on road safety is still the subject of research. This work is intended to contribute to estimating the effect of degraded twin-tube dampers of passenger cars on road safety. An axle model was built using a damper model to simulate different degradation levels. To parameterize the model, a realistic parameter space was estimated based on test rig measurements and database analyses, which is intended to represent the vehicle field in Germany. Within the parameter space, simulations of the axle model were carried out, which calculated the transmittable lateral forces of the various axle configurations as a function of vehicle speed, road surface, damper conditions and axle parameters. A degraded damper has the greatest effect on the transmittable lateral forces at high speeds and in poor road conditions. If a vehicle is traveling at a speed of 100 kph on a Class D road, a degraded damper reduces the transmissible lateral forces of an axle by 20 % on average. For individual parameter configurations, this value can rise to 50 %. The axle parameters that most influence the effect of a degraded damper are the vertical stiffness of the tire, the unsprung mass and the stabilizer stiffness of the axle.Keywords: vehicle dynamics, vehicle simulation, vehicle component degradation, shock absorber model, shock absorber degradation
Procedia PDF Downloads 1162131 Shallow Water Lidar System in Measuring Erosion Rate of Coarse-Grained Materials
Authors: Ghada S. Ellithy, John. W. Murphy, Maureen K. Corcoran
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Erosion rate of soils during a levee or dam overtopping event is a major component in risk assessment evaluation of breach time and downstream consequences. The mechanism and evolution of dam or levee breach caused by overtopping erosion is a complicated process and difficult to measure during overflow due to accessibility and quickly changing conditions. In this paper, the results of a flume erosion tests are presented and discussed. The tests are conducted on a coarse-grained material with a median grain size D50 of 5 mm in a 1-m (3-ft) wide flume under varying flow rates. Each test is performed by compacting the soil mix r to its near optimum moisture and dry density as determined from standard Proctor test in a box embedded in the flume floor. The box measures 0.45 m wide x 1.2 m long x 0.25 m deep. The material is tested several times at varying hydraulic loading to determine the erosion rate after equal time intervals. The water depth, velocity are measured at each hydraulic loading, and the acting bed shear is calculated. A shallow water lidar (SWL) system was utilized to record the progress of soil erodibility and water depth along the scanned profiles of the tested box. SWL is a non-contact system that transmits laser pulses from above the water and records the time-delay between top and bottom reflections. Results from the SWL scans are compared with before and after manual measurements to determine the erosion rate of the soil mix and other erosion parameters.Keywords: coarse-grained materials, erosion rate, LIDAR system, soil erosion
Procedia PDF Downloads 1122130 Identification of Watershed Landscape Character Types in Middle Yangtze River within Wuhan Metropolitan Area
Authors: Huijie Wang, Bin Zhang
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In China, the middle reaches of the Yangtze River are well-developed, boasting a wealth of different types of watershed landscape. In this regard, landscape character assessment (LCA) can serve as a basis for protection, management and planning of trans-regional watershed landscape types. For this study, we chose the middle reaches of the Yangtze River in Wuhan metropolitan area as our study site, wherein the water system consists of rich variety in landscape types. We analyzed trans-regional data to cluster and identify types of landscape characteristics at two levels. 55 basins were analyzed as variables with topography, land cover and river system features in order to identify the watershed landscape character types. For watershed landscape, drainage density and degree of curvature were specified as special variables to directly reflect the regional differences of river system features. Then, we used the principal component analysis (PCA) method and hierarchical clustering algorithm based on the geographic information system (GIS) and statistical products and services solution (SPSS) to obtain results for clusters of watershed landscape which were divided into 8 characteristic groups. These groups highlighted watershed landscape characteristics of different river systems as well as key landscape characteristics that can serve as a basis for targeted protection of watershed landscape characteristics, thus helping to rationally develop multi-value landscape resources and promote coordinated development of trans-regions.Keywords: GIS, hierarchical clustering, landscape character, landscape typology, principal component analysis, watershed
Procedia PDF Downloads 2282129 Comparison of Nutritional Status and Tendency of Depression and Orthorexia Nervosa in Vegan Vegetarian and Omnivorous
Authors: E. Yeşil, M. Özgök, M. Özdemir, B. Köse
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The aim of the present study was to compare nutritional status, tendency of depression and orthorexia nervosa in vegan, vegetarian and omnivorous. The sample consisted of 150 individuals (126 women, 24 men) who agreed to participate in the study between February and May of the year 2018. Fifty vegan, fifty vegetarian and fifty omnivore diet pattern were compared. In the first part, each participant was interviewed using a structured questionnaire to obtain demographic information about education, occupation and health conditions. In the second part Beck Depression Inventory (BDI) was used. In the third part ORTO-11 was used. In the fourth part, 24 Hours Dietary Record was used in order to determine the nutritional status of individuals. The vegans and vegetarians were interviewed about their diets. The mean body mass index of the vegan, vegetarian and omnivore were, 21,24 ± 3,25; 22,2 ± 4,1 and 22,8 ± 4,3 respectively (p > 0,05). The daily energy intakes of the vegan, vegetarian and omnivore diet were 1792,57 ± 784,8 kcal; 1691,9 ± 742,2 kcal and 1697,9 ± 695,6 kcal (p > 0.05). The mean BDI of the vegan, vegetarian and omnivore diet were 6,2 ± 6,2, 9,8 ± 10,1 and 8,8 ± 8,1, respectively (p > 0,05). The mean ORTO-11 of the vegan, vegetarian and omnivore diet were 25,9 ± 4,2, 27,2 ± 5,9 and 26,4 ± 5,3 (p > 0,05). There was a statistically significant correlation between BDI and ORTO-11 in vegan diet group (p: 0,01 r: 0,333). There was a positive correlation between BMI and BDI in the vegetarian group (p: 0,01 r: 0,363). Also in the vegetarian group; there was a negative correlation between age and ORTO-11 (p: 0,01 r: -0,316). A statistically significant negative correlation was found between waist circumference and ORTO-11 (p: 0,05 r: -0,316) in the omnivore diet group. Also there was a negative correlation between age and BDI (p: 0,05 r: -0,338) in this group. As a conclusion, positive correlation was found between BDI and ORTO-11 score of vegan participants. There were no differences between three groups in BDI or ORTO-11 score.Keywords: depression, orthorexia nervosa, vegan, vegetarian
Procedia PDF Downloads 1452128 Strength Parameters and the Rate Process Theory Applied to Compacted Fadama Soils
Authors: Samuel Akinlabi Ola, Emeka Segun Nnochiri, Stephen Kayode Aderomose, Paul Ayesemhe Edoh
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Fadama soils of Northern Nigeria are generally a problem soil for highway and geotechnical engineers. There has been no consistent conclusion on the effect of the strain rate on the shear strength of soils, thus necessitating the need to clarify this issue with various types of soil. Consolidated undrained tests with pore pressure measurements were conducted at optimum moisture content and maximum dry density using standard proctor compaction. Back pressures were applied to saturate the soil. The shear strength parameters were determined. Analyzing the results and model studies using the Rate Process Theory, functional relationships between the deviator stress and strain rate were determined and expressed mathematically as deviator stress = β0+ β1 log(strain rate) at each cell pressure where β0 and β1 are constants. Also, functional relationships between the pore pressure coefficient Āf and the time to failure were determined and expressed mathematically as pore pressure coefficient, Āf = ψ0+ѱ1log (time to failure) where ψ0 and ѱ1 are constants. For cell pressure between 69 – 310 kN/m2 (10 - 45psi) the constants found for Fadama soil in this study are ψ0=0.17 and ѱ1=0.18. The study also shows the dependence of the angle of friction (ø’) on the rate of strain as it increases from 22o to 25o for an increase in the rate of strain from 0.08%/min to 1.0%/min. Conclusively, the study also shows that within the strain rate utilized in the research, the deviator strength increased with the strain rate while the excess pore water pressure decreased with an increase in the rate of strain.Keywords: deviator stress, Fadama soils, pore pressure coefficient, rate process
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