Search results for: mass movement
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 5193

Search results for: mass movement

1713 Evaluation of DNA Oxidation and Chemical DNA Damage Using Electrochemiluminescent Enzyme/DNA Microfluidic Array

Authors: Itti Bist, Snehasis Bhakta, Di Jiang, Tia E. Keyes, Aaron Martin, Robert J. Forster, James F. Rusling

Abstract:

DNA damage from metabolites of lipophilic drugs and pollutants, generated by enzymes, represents a major toxicity pathway in humans. These metabolites can react with DNA to form either 8-oxo-7,8-dihydro-2-deoxyguanosine (8-oxodG), which is the oxidative product of DNA or covalent DNA adducts, both of which are genotoxic and hence considered important biomarkers to detect cancer in humans. Therefore, detecting reactions of metabolites with DNA is an effective approach for the safety assessment of new chemicals and drugs. Here we describe a novel electrochemiluminescent (ECL) sensor array which can detect DNA oxidation and chemical DNA damage in a single array, facilitating a more accurate diagnostic tool for genotoxicity screening. Layer-by-layer assembly of DNA and enzyme are assembled on the pyrolytic graphite array which is housed in a microfluidic device for sequential detection of two type of the DNA damages. Multiple enzyme reactions are run on test compounds using the array, generating toxic metabolites in situ. These metabolites react with DNA in the films to cause DNA oxidation and chemical DNA damage which are detected by ECL generating osmium compound and ruthenium polymer, respectively. The method is further validated by the formation of 8-oxodG and DNA adduct using similar films of DNA/enzyme on magnetic bead biocolloid reactors, hydrolyzing the DNA, and analyzing by liquid chromatography-mass spectrometry (LC-MS). Hence, this combined DNA/enzyme array/LC-MS approach can efficiently explore metabolic genotoxic pathways for drugs and environmental chemicals.

Keywords: biosensor, electrochemiluminescence, DNA damage, microfluidic array

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1712 The Effect of Crack Size, Orientation and Number on the Elastic Modulus of a Cracked Body

Authors: Mark T. Hanson, Alan T. Varughese

Abstract:

Osteoporosis is a disease affecting bone quality which in turn can increase the risk of low energy fractures. Treatment of osteoporosis using Bisphosphonates has the beneficial effect of increasing bone mass while at the same time has been linked to the formation of atypical femoral fractures. This has led to the increased study of micro-fractures in bones of patients using Bisphosphonate treatment. One of the mechanics related issues which have been identified in this regard is the loss in stiffness of bones containing one or many micro-fractures. Different theories have been put forth using fracture mechanics to determine the effect of crack presence on elastic properties such as modulus. However, validation of these results in a deterministic way has not been forthcoming. The present analysis seeks to provide this deterministic evaluation of fracture’s effect on the elastic modulus. In particular, the effect of crack size, crack orientation and crack number on elastic modulus is investigated. In particular, the Finite Element method is used to explicitly determine the elastic modulus reduction caused by the presence of cracks in a representative volume element. Single cracks of various lengths and orientations are examined as well as cases of multiple cracks. Cracks in tension as well as under shear stress are considered. Although the focus is predominantly two-dimensional, some three-dimensional results are also presented. The results obtained show the explicit reduction in modulus caused by the parameters of crack size, orientation and number noted above. The present results allow the interpretation of the various theories which currently exist in the literature.

Keywords: cracks, elastic, fracture, modulus

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1711 A Simplified, Low-Cost Mechanical Design for an Automated Motorized Mechanism to Clean Large Diameter Pipes

Authors: Imad Khan, Imran Shafi, Sarmad Farooq

Abstract:

Large diameter pipes, barrels, tubes, and ducts are used in a variety of applications covering civil and defense-related technologies. This may include heating/cooling networks, sign poles, bracing, casing, and artillery and tank gun barrels. These large diameter assemblies require regular inspection and cleaning to increase their life and reduce replacement costs. This paper describes the design, development, and testing results of an efficient yet simplified, low maintenance mechanical design controlled with minimal essential electronics using an electric motor for a non-technical staff. The proposed solution provides a simplified user interface and an automated cleaning mechanism that requires a single user to optimally clean pipes and barrels in the range of 105 mm to 203 mm caliber. The proposed system employs linear motion of specially designed brush along the barrel using a chain of specific strength and a pulley anchor attached to both ends of the barrel. A specially designed and manufactured gearbox is coupled with an AC motor to allow movement of contact brush with high torque to allow efficient cleaning. A suitably powered AC motor is fixed to the front adapter mounted on the muzzle side whereas the rear adapter has a pulley-based anchor mounted towards the breach block in case of a gun barrel. A mix of soft nylon and hard copper bristles-based large surface brush is connected through a strong steel chain to motor and anchor pulley. The system is equipped with limit switches to auto switch the direction when one end is reached on its operation. The testing results based on carefully established performance indicators indicate the superiority of the proposed user-friendly cleaning mechanism vis-à-vis its life cycle cost.

Keywords: pipe cleaning mechanism, limiting switch, pipe cleaning robot, large pipes

Procedia PDF Downloads 111
1710 Energy Recovery Potential from Food Waste and Yard Waste in New York and Montréal

Authors: T. Malmir, U. Eicker

Abstract:

Landfilling of organic waste is still the predominant waste management method in the USA and Canada. Strategic plans for waste diversion from landfills are needed to increase material recovery and energy generation from waste. In this paper, we carried out a statistical survey on waste flow in the two cities New York and Montréal and estimated the energy recovery potential for each case. Data collection and analysis of the organic waste (food waste, yard waste, etc.), paper and cardboard, metal, glass, plastic, carton, textile, electronic products and other materials were done based on the reports published by the Department of Sanitation in New York and Service de l'Environnement in Montréal. In order to calculate the gas generation potential of organic waste, Buswell equation was used in which the molar mass of the elements was calculated based on their atomic weight and the amount of organic waste in New York and Montréal. Also, the higher and lower calorific value of the organic waste (solid base) and biogas (gas base) were calculated. According to the results, only 19% (598 kt) and 45% (415 kt) of New York and Montréal waste were diverted from landfills in 2017, respectively. The biogas generation potential of the generated food waste and yard waste amounted to 631 million m3 in New York and 173 million m3 in Montréal. The higher and lower calorific value of food waste were 3482 and 2792 GWh in New York and 441 and 354 GWh in Montréal, respectively. In case of yard waste, they were 816 and 681 GWh in New York and 636 and 531 GWh in Montréal, respectively. Considering the higher calorific value, this amount would mean a contribution of around 2.5% energy in these cities.

Keywords: energy recovery, organic waste, urban energy modelling with INSEL, waste flow

Procedia PDF Downloads 138
1709 Factors Affecting Residential Satisfaction in Low-Income Housing: Case Study of War College Housing in Gwarinpa Estate-Abuja, Nigeria

Authors: Abdulmajeed Mustapha, Murat Sahin, Ebru Karahan

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Low-income housing for poor people in urban areas is a global challenge, especially in developing countries. The quality of construction of mass housing is oftentimes compromised, thus resulting in a housing deficit, thereby affecting the residential satisfaction of users. This research analyses the various factors affecting residential satisfaction in War College Housing Estate, Abuja, Nigeria. These were investigated using parameters such as environmental characteristics and public amenities such as public benefits, safety/security, and sociodemographic characteristics. The study adopted a quantitative approach for the data gathering through literature reviews within the topic’s scope. The survey was conducted between April to May 2021 using a questionnaire form that was distributed to household members, onsite analysis within the selected housing project, and interviews with a few professionals within the field of this research. Data gathered from the survey and analysis on housing and sociodemographic characteristics, amongst others, were acquired through the means of interviews and site surveys of the selected Housing Estate. Findings from the various characteristics determining satisfaction revealed that residents had varying levels of satisfaction, ranging from a scale of satisfied to dissatisfied. It is recommended that the government come up with policies that will not only make the environment clean and safe but also make sure that the needs of the people who live there are taken into account. This will help the people who live there be more satisfied with their homes.

Keywords: residential satisfaction, neighborhood satisfaction, low-income housing, socio-demographic characteristics, Nigeria

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1708 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

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1707 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

Abstract:

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

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1706 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

Abstract:

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

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1705 The Information-Seeking Behaviour of Kuwaiti Judges (KJs)

Authors: Essam Mansour

Abstract:

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

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1704 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

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1703 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

Abstract:

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

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1702 Pedagogy to Involve Research Process in an Undergraduate Physical Fitness Course: A Case Study

Authors: Indhumathi Gopal

Abstract:

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

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1701 Dynamic Reliability for a Complex System and Process: Application on Offshore Platform in Mozambique

Authors: Raed KOUTA, José-Alcebiades-Ernesto HLUNGUANE, Eric Châtele

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The search for and exploitation of new fossil energy resources is taking place in the context of the gradual depletion of existing deposits. Despite the adoption of international targets to combat global warming, the demand for fuels continues to grow, contradicting the movement towards an energy-efficient society. The increase in the share of offshore in global hydrocarbon production tends to compensate for the depletion of terrestrial reserves, thus constituting a major challenge for the players in the sector. Through the economic potential it represents, and the energy independence it provides, offshore exploitation is also a challenge for States such as Mozambique, which have large maritime areas and whose environmental wealth must be considered. The exploitation of new reserves on economically viable terms depends on available technologies. The development of deep and ultra-deep offshore requires significant research and development efforts. Progress has also been made in managing the multiple risks inherent in this activity. Our study proposes a reliability approach to develop products and processes designed to live at sea. Indeed, the context of an offshore platform requires highly reliable solutions to overcome the difficulties of access to the system for regular maintenance and quick repairs and which must resist deterioration and degradation processes. One of the characteristics of failures that we consider is the actual conditions of use that are considered 'extreme.' These conditions depend on time and the interactions between the different causes. These are the two factors that give the degradation process its dynamic character, hence the need to develop dynamic reliability models. Our work highlights mathematical models that can explicitly manage interactions between components and process variables. These models are accompanied by numerical resolution methods that help to structure a dynamic reliability approach in a physical and probabilistic context. The application developed makes it possible to evaluate the reliability, availability, and maintainability of a floating storage and unloading platform for liquefied natural gas production.

Keywords: dynamic reliability, offshore plateform, stochastic process, uncertainties

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1700 Wireworms under the Sword of Damocles: Attraction to Maize Root Volatiles

Authors: Diana La Forgia, Jean Baptiste Thibord, François Verheggen

Abstract:

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

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1699 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

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1698 Load-Deflecting Characteristics of a Fabricated Orthodontic Wire with 50.6Ni 49.4Ti Alloy Composition

Authors: Aphinan Phukaoluan, Surachai Dechkunakorn, Niwat Anuwongnukroh, Anak Khantachawana, Pongpan Kaewtathip, Julathep Kajornchaiyakul, Peerapong Tua-Ngam

Abstract:

Aims: The objectives of this study was to determine the load-deflecting characteristics of a fabricated orthodontic wire with alloy composition of 50.6% (atomic weight) Ni and 49.4% (atomic weight) Ti and to compare the results with Ormco, a commercially available pre-formed NiTi orthodontic archwire. Materials and Methods: The ingots alloys with atomic weight ratio 50.6 Ni: 49.4 Ti alloy were used in this study. Three specimens were cut to have wire dimensions of 0.016 inch x0.022 inch. For comparison, a commercially available pre-formed NiTi archwire, Ormco, with dimensions of 0.016 inch x 0.022 inch was used. Three-point bending tests were performed at the temperature 36+1 °C using a Universal Testing Machine on the newly fabricated and commercial archwires to assess the characteristics of the load-deflection curve with loading and unloading forces. The loading and unloading features at the deflection points 0.25, 0.50, 0.75. 1.0, 1.25, and 1.5 mm were compared. Descriptive statistics was used to evaluate each variables, and independent t-test at p < 0.05 was used to analyze the mean differences between the two groups. Results: The load-deflection curve of the 50.6Ni: 49.4Ti wires exhibited the characteristic features of superelasticity. The curves at the loading and unloading slope of Ormco NiTi archwire were more parallel than the newly fabricated NiTi wires. The average deflection force of the 50.6Ni: 49.4Ti wire was 304.98 g and 208.08 g for loading and unloading, respectively. Similarly, the values were 358.02 g loading and 253.98 g for unloading of Ormco NiTi archwire. The interval difference forces between each deflection points were in the range 20.40-121.38 g and 36.72-92.82 g for the loading and unloading curve of 50.6Ni: 49.4Ti wire, respectively, and 4.08-157.08 g and 14.28-90.78 g for the loading and unloading curve of commercial wire, respectively. The average deflection force of the 50.6Ni: 49.4Ti wire was less than that of Ormco NiTi archwire, which could have been due to variations in the wire dimensions. Although a greater force was required for each deflection point of loading and unloading for the 50.6Ni: 49.4Ti wire as compared to Ormco NiTi archwire, the values were still within the acceptable limits to be clinically used in orthodontic treatment. Conclusion: The 50.6Ni: 49.4Ti wires presented the characteristics of a superelastic orthodontic wire. The loading and unloading force were also suitable for orthodontic tooth movement. These results serve as a suitable foundation for further studies in the development of new orthodontic NiTi archwires.

Keywords: 50.6 ni 49.4 Ti alloy wire, load deflection curve, loading and unloading force, orthodontic

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1697 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

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1696 Effects of Monofin Training on Left Ventricular Performance in Elite Egyptian Children Athletes

Authors: Magdy Abouzeid

Abstract:

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 315
1695 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

Abstract:

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 302
1694 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

Abstract:

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

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1693 Analysis of Financial Performance Measurement and Financial Distress Assessment of Highway Companies Listed on Indonesia Stock Exchange before and during COVID-19 Pandemic

Authors: Ari Prasetyo, Taufik Faturohman

Abstract:

The COVID-19 pandemic in Indonesia is part of the ongoing worldwide pandemic of coronavirus disease 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). It was confirmed to have spread to Indonesia on 2 March 2020. Moreover, the government of Indonesia has been conducting a local lockdown to limit people's movement from one city to another city. Therefore, this situation has impact on business operation, especially on highway companies listed on the Indonesia stock exchange. This study evaluates and measures three companies’ financial performance and health conditions before and during the COVID-19 pandemic from 2016 – 2020. The measurement is conducted by using financial ratio analysis and the Altman Z-score method. The ratio used to measure the financial ratio analysis is taken from the decree of the Ministry of SOE’s KEP-100/MBU/2002 about the company’s health level condition. From the decree, there are eight financial ratios used such as return on equity (ROE), return on investment (ROI), current ratio, cash ratio, collection period, inventory turnover, total asset turnover, and total equity to total asset. Altman Z-score is used to calculate the financial distress condition. The result shows that the highway companies for the period 2016 – 2020 are as follows: PT Jasa Marga (Persero) Tbk (AA, BB, BB, BB, C), PT Citra Marga Nusaphala Persada Tbk (BB, AA, BB, BBB, C), and PT Nusantara Infrastructure Tbk (BB, BB, AA, BBB, C). In addition, the Altman Z-score assessment performed in 2016-2020 shows that PT Jasa Marga (Persero) Tbk was in the grey zone area for 2015-2018 and in the distress zone for 2019-2020. PT Citra Marga Nusaphala Persada Tbk was in the grey zone area for 2015-2019 and in the distress zone for 2020. PT Nusantara Infrastructure Tbk was in the grey zone area for 2015-2018 and in the distress zone for 2019-2020.

Keywords: financial performance, financial ratio, Altman Z-score, financial distress, highway company

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1692 Determining the Presence of Brucella abortus Antibodies by the Indirect Elisa Method in Bovine Bulk Milk and Risk Factors in the Peri-Urban Zones of Bamenda Cameroon

Authors: Cha-ah C. N., Awah N. J., Mouiche M. M. M.

Abstract:

Brucellosis is a neglected zoonotic disease of animals and man caused by bacteria of genus Brucella. Though eradicated in some parts of the world, it remains endemic in sub-Saharan Africa including Cameroon. The aim of this study was to contribute to the epidemiology of brucellosis in the North-West region of Cameroon by detecting the presence of anti-Brucella antibodies in bovine bulk milk as this serves as a route of transmission from animals to man. A cross sectional study was conducted to determine the prevalence of Brucella abortus antibodies in bovine bulk milk in the peri-urban zones of Bamenda. One hundred bulk milk samples were collected from 100 herds and tested by milk I-ELISA test. The conducted study revealed the presence of anti-Brucella abortus antibodies in bovine bulk milk. The study revealed that bovine brucellosis is widespread in animal production systems in this area. The animal infection pressure in these systems has remained strong due to movement of livestock in search of pasture, co-existence of animal husbandry, communal sharing of grazing land, concentration of animals around water points, abortions in production systems, locality of production systems and failure to quarantine upon introduction of new animals. The circulation of Brucella abortus antibodies in cattle farms recorded in the study revealed potential public health implication and suggest economic importance of brucellosis to the cattle industry in the Northwest region of Cameroon. The risk for re-emergence and transmission of brucellosis is evident as a result of the co-existence of animal husbandry activities and social-cultural activities that promote brucellosis transmission. Well-designed countrywide, evidence-based studies of brucellosis are needed. These could help to generate reliable frequency and potential impact estimates, to identify Brucella reservoirs, and to propose control strategies of proven efficacy.

Keywords: brucellosis, bulk milk, northwest region Cameroon, prevalence

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1691 Anti-Melanogenesis and Anti-Inflammatory Effects of Opuntia humifusa

Authors: Yonghwa Lee, Yoon Suk Kim, Yongsub Yi

Abstract:

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

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1690 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

Abstract:

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

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1689 Simulative Study of the Influence of Degraded Twin-Tube Shock Absorbers on the Lateral Forces of Vehicle Axles

Authors: Tobias Schramm, Günther Prokop

Abstract:

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 121
1688 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

Abstract:

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

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1687 Isolation, Characterization and Quantitation of Anticancer Constituent from Chloroform Extract of N. arbortristis L. Leaves

Authors: Parul Grover, K. A. Suri, Raj Kumar, Gulshan Bansal

Abstract:

Background: Nyctanthes arbortristis Linn is traditionally used as anticancer herb in Indian system of medicine, but its introduction into modern system of medicine is still awaited due to lack of systematic scientific studies. Objective: The objective of the present study was to isolate and characterize anticancer phytoconstituents from N. arbortristis L. leaves based on bioactivity guided fractionation. Method: Different extracts of the leaves of the plant were prepared by Soxhlet extractor. Each extract was evaluated for anticancer activity against HL-60 cell lines. Chloroform and HA extract showed potent anticancer activity and hence were selected for fractionation. Fraction C1 from chloroform extract was found to be most potent amongst all when tested against three cell lines (HL-60, A-549, and HCT-116) and thus was selected for further fractionation and a pure compound CP-01 was isolated. RP-HPLC method has been developed for quantification of isolated compound by using Kinetex C-18 column with gradient elution at 0.7 mL/min using mobile phase containing potassium dihydrogen phosphate (0.01 M, pH 3.0) with acetonitrile. The wavelength of maximum absorption (λₘₐₓ) selected was 210 nm. Results: The structure of potent anticancer CP-01 was determined on the basis spectroscopic methods like IR, 1H-NMR, ¹³C-NMR and Mass Spectrometry and it was characterized as 1,1,2-tris(2’,4’-di-tert-butylbenzene)-4,4-dimethyl-pent-1-ene. The content of CP-01 was found to be 0.88 %w/w of chloroform extract and 0.08 %w/w of N.arbortristis leaves. Conclusion: The study supports the traditional use of N. arbortristis as anticancer herb & the identified compound CP-01 can serve as an excellent lead to develop potent and safe anticancer drugs.

Keywords: anticancer, HL-60 cell lines, Nyctanthes arbor-tristis, RP-HPLC

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1686 A Simple, Precise and Cost Effective PTFE Container Design Capable to Work in Domestic Microwave Oven

Authors: Mehrdad Gholami, Shima Behkami, Sharifuddin B. Md. Zain, Firdaus A. B. Kamaruddin

Abstract:

Starting from the first application of a microwave oven for sample preparation in 1975 for the purpose of wet ashing of biological samples using a domestic microwave oven, many microwave-assisted dissolution vessels have been developed. The advanced vessels are armed with special safety valve that release the excess of pressure while the vessels are in critical conditions due to applying high power of microwave. Nevertheless, this releasing of pressure may cause lose of volatile elements. In this study Teflon bottles are designed with relatively thicker wall compared to commercial ones and a silicone based polymer was used to prepare an O-ring which plays the role of safety valve. In this design, eight vessels are located in an ABS holder to keep them stable and safe. The advantage of these vessels is that they need only 2 mL of HNO3 and 1mL H2O2 to digest different environmental samples, namely, sludge, apple leave, peach leave, spinach leave and tomato leave. In order to investigate the performance of this design an ICP-MS instrument was applied for multi elemental analysis of 20 elements on the SRM of above environmental samples both using this design and a commercial microwave digestion design. Very comparable recoveries were obtained from this simple design with the commercial one. Considering the price of ultrapure chemicals and the amount of them which normally is about 8-10 mL, these simple vessels with the procedures that will be discussed in detail are very cost effective and very suitable for environmental studies.

Keywords: inductively coupled plasma mass spectroscopy (ICP-MS), PTFE vessels, Teflon bombs, microwave digestion, trace element

Procedia PDF Downloads 341
1685 Designing and Prototyping Permanent Magnet Generators for Wind Energy

Authors: T. Asefi, J. Faiz, M. A. Khan

Abstract:

This paper introduces dual rotor axial flux machines with surface mounted and spoke type ferrite permanent magnets with concentrated windings; they are introduced as alternatives to a generator with surface mounted Nd-Fe-B magnets. The output power, voltage, speed and air gap clearance for all the generators are identical. The machine designs are optimized for minimum mass using a population-based algorithm, assuming the same efficiency as the Nd-Fe-B machine. A finite element analysis (FEA) is applied to predict the performance, emf, developed torque, cogging torque, no load losses, leakage flux and efficiency of both ferrite generators and that of the Nd-Fe-B generator. To minimize cogging torque, different rotor pole topologies and different pole arc to pole pitch ratios are investigated by means of 3D FEA. It was found that the surface mounted ferrite generator topology is unable to develop the nominal electromagnetic torque, and has higher torque ripple and is heavier than the spoke type machine. Furthermore, it was shown that the spoke type ferrite permanent magnet generator has favorable performance and could be an alternative to rare-earth permanent magnet generators, particularly in wind energy applications. Finally, the analytical and numerical results are verified using experimental results.

Keywords: axial flux, permanent magnet generator, dual rotor, ferrite permanent magnet generator, finite element analysis, wind turbines, cogging torque, population-based algorithms

Procedia PDF Downloads 152
1684 Correlation of Nutritional Status and Anemia Among School-Aged Children in Indonesian Urban Area

Authors: William Cheng, Yuni Astria, Rini Sekartini

Abstract:

Background: Prevalence of anemia among school-aged children is relatively high (25.4%). This condition can affect children’s life, including cognitive function. One of the most common factors that is associated with anemia in children is nutritional status. This simple indicator will be very helpful in identifying more population at risk. The aim of this study is to correlate the clinical implication of nutritional status to the prevalence of anemia in children, with intention to determine a more effective nutritional status indicator in detecting anemia. Method: Anthropometric and haemoglobin status were gathered from children between 5 to 7-years-old in one of the urban areas in Jakarta in 2012. We identified children with haemoglobin level under 11.5 as anemia and correlated them to their WHO z-score from each of these indicators: Body Weight for Age (normal weight and underweight), Height for Age (not stunted and stunted), and Body Mass Index for Age (not wasted and wasted). Results: A total of 195 children were included in this research and 57 of them (29,2%) were diagnosed as anemia. The majority of the children had good nutritional status, however, 30 (15,4%) of them were found to be underweight, 33 (16,9%) were stunted, and 1 children (0,5%) was wasted. There were no overweight result found in this population. From the three nutritional status indicators, none proved to be statistically significant in relation to the incidence of anemia (p>0.05). Out of 33 children who were diagnosed as stunted, 36.36 % were found to have anemia, in comparison to 27,7% of children who were not stunted. Meanwhile, among 30 children who were diagnosed as underweight, 33,3 % of them were anemic whereas only 28,4% of the normal weight group were anemic. Conclusion: In this study, there is no significant correlation between anemia with any nutritional status indicator. However, more than a third of the stunted children are proven to have low haemoglobin status. The finding of stunting in children should be given more attention to further investigate for anemia.

Keywords: school-aged children, nutritional status, anemia, pediatrics

Procedia PDF Downloads 562