Search results for: Micro and Small Scale (MMS) businesses
4050 Pushing the Boundary of Parallel Tractability for Ontology Materialization via Boolean Circuits
Authors: Zhangquan Zhou, Guilin Qi
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Materialization is an important reasoning service for applications built on the Web Ontology Language (OWL). To make materialization efficient in practice, current research focuses on deciding tractability of an ontology language and designing parallel reasoning algorithms. However, some well-known large-scale ontologies, such as YAGO, have been shown to have good performance for parallel reasoning, but they are expressed in ontology languages that are not parallelly tractable, i.e., the reasoning is inherently sequential in the worst case. This motivates us to study the problem of parallel tractability of ontology materialization from a theoretical perspective. That is we aim to identify the ontologies for which materialization is parallelly tractable, i.e., in the NC complexity. Since the NC complexity is defined based on Boolean circuit that is widely used to investigate parallel computing problems, we first transform the problem of materialization to evaluation of Boolean circuits, and then study the problem of parallel tractability based on circuits. In this work, we focus on datalog rewritable ontology languages. We use Boolean circuits to identify two classes of datalog rewritable ontologies (called parallelly tractable classes) such that materialization over them is parallelly tractable. We further investigate the parallel tractability of materialization of a datalog rewritable OWL fragment DHL (Description Horn Logic). Based on the above results, we analyze real-world datasets and show that many ontologies expressed in DHL belong to the parallelly tractable classes.Keywords: ontology materialization, parallel reasoning, datalog, Boolean circuit
Procedia PDF Downloads 2714049 The Comparation of Limits of Detection of Lateral Flow Immunochromatographic Strips of Different Types of Mycotoxins
Authors: Xinyi Zhao, Furong Tian
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Mycotoxins are secondary metabolic products of fungi. These are poisonous, carcinogens and mutagens in nature and pose a serious health threat to both humans and animals, causing severe illnesses and even deaths. The rapid, simple and cheap detection methods of mycotoxins are of immense importance and in great demand in the food and beverage industry as well as in agriculture and environmental monitoring. Lateral flow immunochromatographic strips (ICSTs) have been widely used in food safety, environment monitoring. Forty-six papers were identified and reviewed on Google Scholar and Scopus for their limit of detection and nanomaterial on Lateral flow immunochromatographic strips on different types of mycotoxins. The papers were dated 2001-2021. Twenty five papers were compared to identify the lowest limit of detection of among different mycotoxins (Aflatoxin B1: 10, Zearalenone:5, Fumonisin B1: 5, Trichothecene-A: 5). Most of these highly sensitive strips are competitive. Sandwich structure are usually used in large scale detection. In conclusion, the mycotoxin receives that most researches is aflatoxin B1 and its limit of detection is the lowest. Gold-nanopaticle based immunochromatographic test strips has the lowest limit of detection. Five papers involve smartphone detection and they all detect aflatoxin B1 with gold nanoparticles. In these papers, quantitative concentration results can be obtained when the user uploads the photograph of test lines using the smartphone application.Keywords: aflatoxin B1, limit of detection, gold nanoparticle, lateral flow immunochromatographic strips, mycotoxins
Procedia PDF Downloads 1954048 Ghost Frequency Noise Reduction through Displacement Deviation Analysis
Authors: Paua Ketan, Bhagate Rajkumar, Adiga Ganesh, M. Kiran
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Low gear noise is an important sound quality feature in modern passenger cars. Annoying gear noise from the gearbox is influenced by the gear design, gearbox shaft layout, manufacturing deviations in the components, assembly errors and the mounting arrangement of the complete gearbox. Geometrical deviations in the form of profile and lead errors are often present on the flanks of the inspected gears. Ghost frequencies of a gear are very challenging to identify in standard gear measurement and analysis process due to small wavelengths involved. In this paper, gear whine noise occurring at non-integral multiples of gear mesh frequency of passenger car gearbox is investigated and the root cause is identified using the displacement deviation analysis (DDA) method. DDA method is applied to identify ghost frequency excitations on the flanks of gears arising out of generation grinding. Frequency identified through DDA correlated with the frequency of vibration and noise on the end-of-line machine as well as vehicle level measurements. With the application of DDA method along with standard lead profile measurement, gears with ghost frequency geometry deviations were identified on the production line to eliminate defective parts and thereby eliminate ghost frequency noise from a vehicle. Further, displacement deviation analysis can be used in conjunction with the manufacturing process simulation to arrive at suitable countermeasures for arresting the ghost frequency.Keywords: displacement deviation analysis, gear whine, ghost frequency, sound quality
Procedia PDF Downloads 1464047 Migration, Food Security, Rapid Urbanization and Population Rise in Nigeria: A Wake-Up Call to Policy-Makers
Authors: A. E. Obayelu, S. O. Olubiyo
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Food is different from other commodities because everybody needs food for survival. This has led to a shift in focus to food security in the global policy arena. However, there is paucity of studies on the interactions between food security, migration, urbanization and population rise. This paper therefore look at the linkages between migration and food security in the context of rapid urbanization and population rise of Nigeria. The study obtained data and information from both secondary sources and primary method through the voice of some selected Nigerians through telephone interview. The findings revealed that, the primary factor for the rapid urbanization in Nigeria is migration; most foods are still produced by peasant farmers who are scattered all over the rural areas and not multinational companies who produce on large scale. The country is still characterized with inadequate infrastructural facilities and services to cater for growing population. There are no protective policies enforced by the Nigeria government. In most cases, the migrants are left entirely on mercy of what they can find to due for survival. The most common coping mechanisms by migrants from rural to urban areas are changing food intake in terms of quantity, quality, diversity and frequency and prioritizing children. Policies that address urban food security need to consider the complex relationship between rapid population rise and migration and appropriate transformations that will be able to manage urbanization. With increasing rate of urbanization, the focus of food security should no longer be that of rural onlyKeywords: agricultural commercialization, agricultural transformation, food security, urban, urbanization
Procedia PDF Downloads 4294046 Visualizing the Future of New York’s Southern Tier: Engaging Students to Help Create Sustainable Communities
Authors: William C. Dean
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In the pedagogical sequence of the four- and five-year architectural programs at Alfred State, the fourth-year Urban Design Studio constitutes the first course where students directly explore design issues in the urban context. It is the first large-scale, community-based service learning project for most of the participating students. The students learn key lessons that include the benefits of working both individually and in groups of different sizes toward a common goal, accepting - and responding creatively too - criticism from stakeholders at different points in the project, and recognizing the role that local politics and activism can play in planning for community development. Above all, students are exposed to the importance of good planning in relation to preservation and community revitalization. The purpose of this paper is to discuss the use of community-based service-learning projects in undergraduate architectural education to promote student civic engagement as a means of helping communities visualize potential solutions for revitalizing their neighborhoods and business districts. A series of case studies will be presented in terms of challenges that were encountered, opportunities for student engagement and leadership, and the feasibility of sustainable community development resulting from those projects. The reader will be encouraged to consider how they can recognize needs within their own communities that could benefit from the assistance of architecture students and faculty.Keywords: urban design, service-learning, civic engagement, community revitalization
Procedia PDF Downloads 954045 Compromising Quality of Life in Low-Income Settlements: The Case of Ashrayan Prakalpa, Khulna
Authors: Salma Akter, Md. Kamal Uddin
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Quality of life is a vast and comprehensive concept refers overall well-being of society. Current research and efforts of policymakers and planners are concerned to increase the urban quality of life through the sustainable development of city and country. While such efforts effectively improve the quality of life of urban dwellers through improved social, economic and housing infrastructures, very little has been paid to improve low-income settlement users more specifically government provided shelter projects. The top-down shelter policies and its objective indicators (physical design elements and physical environmental elements) indicators on low-income groups merely can ensure grassroots needs, aspiration and well-being refer as subjective qualities obliged to compromise with the quality of life. This research, therefore, aims to measure the quality of life of such government-provided low-income settlements. To do so, a conceptual framework has been developed to measure quality of life with arguing that quality of life depends on both objective and subjective indicators and needs to measure across three scales of living environment refers to macro (community), meso (neighborhood or shelter/built environment), and micro (family). The top-down shelter project, Dakshin Chandani Mahal Ashrayan Prakalpa is a resettlement/housing project of Government of Bangladesh for providing shelters and human resources development activities like education, microcredit, and training programme to landless, homeless and rootless people has been taken as case study. The study area is located at Dighalia Upazila, Khulna Bangladesh. In terms of methodology, this research is primarily exploratory and adopts a case study method and deductive approach for evaluating the quality of life. Data have been obtained from relevant literature review, key informant interview, focus group discussion, necessary drawings, photographs and participant observation across dwelling, neighborhood, and community level. Findings have revealed that Shelter users mostly compromise the quality of life at community level due to insufficient physical design elements and facilities while neighborhood and dwelling level have been manifested similar result like former ones. Thus, the outcome of this study can be beneficial for a global-level understating of the compromising the ‘quality of life’ under top-down shelter policy. Locally, for instance, in the context of Bangladesh, it can help policymakers and concerned authorities to formulate the shelter policies and take initiatives to improve the well-being of marginalized.Keywords: Ashrayan Prakalpa, compromise, displaced people, quality of life
Procedia PDF Downloads 2174044 The Influence of Teacher’s Non-Verbal Communication on Ondo State Secondary School Students’ Learning Outcomes in English Language
Authors: Bola M. Tunde-Awe
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The study investigated the influence of teacher’s non-verbal communication on secondary school students’ learning outcomes in English language. The study was a survey research. Participants were three hundred Senior Secondary School II students randomly selected from ten schools in Akoko South West Local Government Area of Ondo State, Nigeria. The instrument used for data collection was a questionnaire containing twenty items on a four-point Likert scale which measured teacher’s use of three types of non-verbal communication modes: body movement, eye contact and spatial distance. The data collected was analysed using simple percentage. Findings revealed that teacher’s use of these non-verbal communication modes enhanced learners’ learning outcomes in English language: a total of 271 (90.33%) participants affirmed that teacher’s body language influenced their learning of English; 224 (74.66%) maintained the same stand for eye contact; while 202 (67.33%) affirmed that teacher’s spatial distance had positive influence. Consequent upon these findings, it was recommended that teachers of English language should constantly utilize non-verbal communication in their instructional delivery. Also, non-verbal communication modes should be included in teacher education programme to equip prospective pre-service teachers with the art of non-verbal communication.Keywords: non-verbal communication, body language, eye contact, spatial distance, learning outcomes
Procedia PDF Downloads 4214043 Evolving Mango Metaphor In Diaspora Literature: Maintaining Immigrant Identity Through Foodways
Authors: Constance Kirker
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This paper examines examples of the shared use of mango references as a culinary metaphor powerful in maintaining immigrant identity in the works of diaspora authors from a variety of regions of the world, including South Asia, the Caribbean, and Africa, and across a variety of genres, including novels, culinary memoirs, and children’s books. There has been past criticism of so-called sari-mango literature, suggesting that use of the image of mango is a cliché, even “lazy,” attempt to “exoticize” and sentimentalize South Asia in particular. A broader review across national boundaries reveals that diaspora authors, including those beyond South Asia, write nostalgically about mango as much about the messy “full body” tactile experience of eating a mango as about the “exotic” quality of mango representing the “otherness” of their home country. Many of the narratives detail universal childhood food experiences that are more shared than exotic, such as a desire to subvert the adult societal rules of neatness and get very messy, or memories of small but memorable childhood transgressions such as stealing mangoes from a neighbor’s tree. In recent years, food technology has evolved, and mangoes have become more familiar and readily available in Europe and America, from smoothies and baby food to dried fruit snacks. The meaning associated with the imagery of mangoes for both writers and readers in diaspora literature evolves as well, and authors do not have to heed Salman Rushdie’s command, “There must be no tropical fruits in the title. No mangoes.”Keywords: identity, immigrant diaspora, culinary metaphor, food studies
Procedia PDF Downloads 1114042 Energy Efficiency Improvement of Excavator with Independent Metering Valve by Continuous Mode Changing Considering Engine Fuel Consumption
Authors: Sang-Wook Lee, So-Yeon Jeon, Min-Gi Cho, Dae-Young Shin, Sung-Ho Hwang
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Hydraulic system of excavator gets working energy from hydraulic pump which is connected to output shaft of engine. Recently, main control valve (MCV) which is composed of several independent metering valve (IMV) has been introduced for better energy efficiency of the hydraulic system so that fuel efficiency of the excavator can be improved. Excavator with IMV has 5 operating modes depending on the quantity of regeneration flow. In this system, the hydraulic pump is controlled to supply demanded flow which is needed to operate each mode. Because the regenerated flow supply energy to actuators, the hydraulic pump consumes less energy to make same motion than one that does not regenerate flow. The horse power control is applied to the hydraulic pump of excavator for maintaining engine start under a heavy load and this control makes the flow of hydraulic pump reduced. When excavator is in complex operation such as loading or unloading soil, the hydraulic pump discharges small quantity of working fluid in high pressure. At this operation, the engine of excavator does not run at optimal operating line (OOL). The engine needs to be operated on OOL to improve fuel efficiency and by controlling hydraulic pump the engine can drive on OOL. By continuous mode changing of IMV, the hydraulic pump is controlled to make engine runs on OOL. The simulation result of this study shows that fuel efficiency of excavator with IMV can be improved by considering engine OOL and continuous mode changing algorithm.Keywords: continuous mode changing, engine fuel consumption, excavator, fuel efficiency, IMV
Procedia PDF Downloads 3854041 Gender Differences in Adolescent Avatars: Gender Consistency and Masculinity-Femininity of Nicknames and Characters
Authors: Monika Paleczna, Małgorzata Holda
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Choosing an avatar's gender in a computer game is one of the key elements in the process of creating an online identity. The selection of a male or female avatar can define the entirety of subsequent decisions regarding both appearance and behavior. However, when the most popular games available for the Nintendo console in 1998 were analyzed, it turned out that 41% of computer games did not have female characters. Nowadays, players create their avatars based mainly on binary gender classification, with male and female characters to choose from. The main aim of the poster is to explore gender differences in adolescent avatars. 130 adolescents aged 15-17 participated in the study. They created their avatars and then played a computer game. The creation of the avatar was based on the choice of gender, then physical and mental characteristics. Data on gender consistency (consistency between participant’s sex and gender selected for the avatar) and masculinity-femininity of avatar nicknames and appearance will be presented. The masculinity-femininity of avatar nicknames and appearance was assessed by expert raters on a very masculine to very feminine scale. Additionally, data on the relationships of the perceived levels of masculinity-femininity with hostility-friendliness and the intelligence of avatars will be shown. The dimensions of hostility-friendliness and intelligence were also assessed by expert raters on scales ranging from very hostile to very friendly and from very low intelligence to very high intelligence.Keywords: gender, avatar, adolescence, computer games
Procedia PDF Downloads 2144040 Stability and Rheology of Sodium Diclofenac-Loaded and Unloaded Palm Kernel Oil Esters Nanoemulsion Systems
Authors: Malahat Rezaee, Mahiran Basri, Raja Noor Zaliha Raja Abdul Rahman, Abu Bakar Salleh
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Sodium diclofenac is one of the most commonly used drugs of nonsteroidal anti-inflammatory drugs (NSAIDs). It is especially effective in the controlling the severe conditions of inflammation and pain, musculoskeletal disorders, arthritis, and dysmenorrhea. Formulation as nanoemulsions is one of the nanoscience approaches that have been progressively considered in pharmaceutical science for transdermal delivery of drug. Nanoemulsions are a type of emulsion with particle sizes ranging from 20 nm to 200 nm. An emulsion is formed by the dispersion of one liquid, usually the oil phase in another immiscible liquid, water phase that is stabilized using surfactant. Palm kernel oil esters (PKOEs), in comparison to other oils; contain higher amounts of shorter chain esters, which suitable to be applied in micro and nanoemulsion systems as a carrier for actives, with excellent wetting behavior without the oily feeling. This research was aimed to study the effect of O/S ratio on stability and rheological behavior of sodium diclofenac loaded and unloaded palm kernel oil esters nanoemulsion systems. The effect of different O/S ratio of 0.25, 0.50, 0.75, 1.00 and 1.25 on stability of the drug-loaded and unloaded nanoemulsion formulations was evaluated by centrifugation, freeze-thaw cycle and storage stability tests. Lecithin and cremophor EL were used as surfactant. The stability of the prepared nanoemulsion formulations was assessed based on the change in zeta potential and droplet size as a function of time. Instability mechanisms including coalescence and Ostwald ripening for the nanoemulsion system were discussed. In comparison between drug-loaded and unloaded nanoemulsion formulations, drug-loaded formulations represented smaller particle size and higher stability. In addition, the O/S ratio of 0.5 was found to be the best ratio of oil and surfactant for production of a nanoemulsion with the highest stability. The effect of O/S ratio on rheological properties of drug-loaded and unloaded nanoemulsion systems was studied by plotting the flow curves of shear stress (τ) and viscosity (η) as a function of shear rate (γ). The data were fitted to the Power Law model. The results showed that all nanoemulsion formulations exhibited non-Newtonian flow behaviour by displaying shear thinning behaviour. Viscosity and yield stress were also evaluated. The nanoemulsion formulation with the O/S ratio of 0.5 represented higher viscosity and K values. In addition, the sodium diclofenac loaded formulations had more viscosity and higher yield stress than drug-unloaded formulations.Keywords: nanoemulsions, palm kernel oil esters, sodium diclofenac, rheoligy, stability
Procedia PDF Downloads 4234039 Social Support and Quality of Life of Youth Suffering from Cerebral Palsy Temporarily Orphaned Due to Emigration of a Parent
Authors: A. Gagat-Matuła
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The article is concerned in the issue of social support and quality of life of youth suffering from cerebral palsy, who are temporarily orphaned due to the emigration of a parent. Migration causes multi-aspect consequences in various spheres of life. They are particularly severe for the functioning of families. Temporal parting of parents and children, especially the disabled, is a difficult situation. In this case, the family structure is changed, as well as the quality of life of its members. Children can handle migration parting in a better or worse way; these can be divided into properly functioning and manifesting behaviour disorders. In conditions of the progressing phenomenon of labour migration of Poles and a wide spectrum of consequences for the whole social life, it is essential to undertake actions aimed at support of migrants and their families. This article focuses mainly on social support and quality of families members, of which, are the labour migrants perceived by youth suffering from cerebral palsy. The quantitative method was used in this study. In the study, the Satisfaction with Life Scale (SWLS) by Diener, was used. The analysed group consisted of 50 persons (37 girls and 13 boys), aged 16 years to 18 years, whose parents are labour migrants. The results indicate that the quality of life and social support for youth suffering from cerebral palsy who are temporarily orphaned is at a low and average level.Keywords: social support, quality of life, migration, cerebral palsy
Procedia PDF Downloads 1914038 Static Analysis of Security Issues of the Python Packages Ecosystem
Authors: Adam Gorine, Faten Spondon
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Python is considered the most popular programming language and offers its own ecosystem for archiving and maintaining open-source software packages. This system is called the python package index (PyPI), the repository of this programming language. Unfortunately, one-third of these software packages have vulnerabilities that allow attackers to execute code automatically when a vulnerable or malicious package is installed. This paper contributes to large-scale empirical studies investigating security issues in the python ecosystem by evaluating package vulnerabilities. These provide a series of implications that can help the security of software ecosystems by improving the process of discovering, fixing, and managing package vulnerabilities. The vulnerable dataset is generated using the NVD, the national vulnerability database, and the Snyk vulnerability dataset. In addition, we evaluated 807 vulnerability reports in the NVD and 3900 publicly known security vulnerabilities in Python Package Manager (pip) from the Snyk database from 2002 to 2022. As a result, many Python vulnerabilities appear in high severity, followed by medium severity. The most problematic areas have been improper input validation and denial of service attacks. A hybrid scanning tool that combines the three scanners bandit, snyk and dlint, which provide a clear report of the code vulnerability, is also described.Keywords: Python vulnerabilities, bandit, Snyk, Dlint, Python package index, ecosystem, static analysis, malicious attacks
Procedia PDF Downloads 1404037 Probabilistic Models to Evaluate Seismic Liquefaction In Gravelly Soil Using Dynamic Penetration Test and Shear Wave Velocity
Authors: Nima Pirhadi, Shao Yong Bo, Xusheng Wan, Jianguo Lu, Jilei Hu
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Although gravels and gravelly soils are assumed to be non-liquefiable because of high conductivity and small modulus; however, the occurrence of this phenomenon in some historical earthquakes, especially recently earthquakes during 2008 Wenchuan, Mw= 7.9, 2014 Cephalonia, Greece, Mw= 6.1 and 2016, Kaikoura, New Zealand, Mw = 7.8, has been promoted the essential consideration to evaluate risk assessment and hazard analysis of seismic gravelly soil liquefaction. Due to the limitation in sampling and laboratory testing of this type of soil, in situ tests and site exploration of case histories are the most accepted procedures. Of all in situ tests, dynamic penetration test (DPT), Which is well known as the Chinese dynamic penetration test, and shear wave velocity (Vs) test, have been demonstrated high performance to evaluate seismic gravelly soil liquefaction. However, the lack of a sufficient number of case histories provides an essential limitation for developing new models. This study at first investigates recent earthquakes that caused liquefaction in gravelly soils to collect new data. Then, it adds these data to the available literature’s dataset to extend them and finally develops new models to assess seismic gravelly soil liquefaction. To validate the presented models, their results are compared to extra available models. The results show the reasonable performance of the proposed models and the critical effect of gravel content (GC)% on the assessment.Keywords: liquefaction, gravel, dynamic penetration test, shear wave velocity
Procedia PDF Downloads 2014036 Factors Influencing Health-related Quality of Life in Thai AMI Survivors
Authors: K. Masingboon, S. Duangpaeng, N. Chaiwong
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Acute myocardial infarction (AMI) is the most common cause of death among Thai with coronary heart disease (CHD). Thai AMI survivors are most likely to have impaired health-related quality of life (HRQoL) due to their lifestyle, functional, and psychological problems. Guided by the Individual and Family Self-Management Theory, this study aimed to explore HRQoL and identify its predictors among Thai AMI survivors. 155 Thai AMI survivors were recruited by stratified random sampling from three hospitals located in eastern region of Thailand. HRQol was measured using the Short Form -12 Health Survey (SF-12). The Center for Epidemiologic studies Depression Scale (CES-D) was utilized to assess the presence of depression, and the Family Support questionnaire was administered to examine family support. Results revealed that 92 percent of Thai AMI survivors reported a generally high level of HRQoL and 80 percent of them reported higher level of HRQoL in physical health and mental health dimension. Depression and family support were significantly predicted HRQoL among Thai AMI survivors and accounted for 28.5 percent of variance (p < .001). Interestingly, depression was the most significant predictors of HRQoL (β = -.65, p < .001) In conclusion, depression is a significant predictor of HRQoL in Thai AMI survivors. Increasing awareness of depression among these survivors is important. Depressive symptoms in should be routinely assessed. In addition, intervention to improve HRQoL among Thai AMI survivors should be addressed through depressive symptom management and family collaboration.Keywords: health-related quality of life, AMI survivors, predictors, collaboration
Procedia PDF Downloads 3264035 Development and Control of Deep Seated Gravitational Slope Deformation: The Case of Colzate-Vertova Landslide, Bergamo, Northern Italy
Authors: Paola Comella, Vincenzo Francani, Paola Gattinoni
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This paper presents the Colzate-Vertova landslide, a Deep Seated Gravitational Slope Deformation (DSGSD) located in the Seriana Valley, Northern Italy. The paper aims at describing the development as well as evaluating the factors that influence the evolution of the landslide. After defining the conceptual model of the landslide, numerical simulations were developed using a finite element numerical model, first with a two-dimensional domain, and later with a three-dimensional one. The results of the 2-D model showed a displacement field typical of a sackung, as a consequence of the erosion along the Seriana Valley. The analysis also showed that the groundwater flow could locally affect the slope stability, bringing about a reduction in the safety factor, but without reaching failure conditions. The sensitivity analysis carried out on the strength parameters pointed out that slope failures could be reached only for relevant reduction of the geotechnical characteristics. Such a result does not fit the real conditions observed on site, where a number of small failures often develop all along the hillslope. The 3-D model gave a more comprehensive analysis of the evolution of the DSGSD, also considering the border effects. The results showed that the convex profile of the slope favors the development of displacements along the lateral valley, with a relevant reduction in the safety factor, justifying the existing landslides.Keywords: deep seated gravitational slope deformation, Italy, landslide, numerical modeling
Procedia PDF Downloads 3654034 Influence of the Molar Concentration and Substrate Temperature on Fluorine-Doped Zinc Oxide Thin Films Chemically Sprayed
Authors: J. Ramirez, A. Maldonado, M. de la L. Olvera
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The effect of both the molar concentration of the starting solution and the substrate temperature on the electrical, morphological, structural and optical properties of chemically sprayed fluorine-doped zinc oxide (ZnO:F) thin films deposited on glass substrates, is analyzed in this work. All the starting solutions employed were aged for ten days before the deposition. The results show that as the molar concentration increases, a decrease in the electrical resistivity values is obtained, reaching the minimum in films deposited from a 0.4 M solution at 500°C. A further increase in the molar concentration leads to a very slight increase in the resistivity. On the other hand, as the substrate temperature is increased, the resistivity decreases and a tendency towards to minimum value is evidenced; taking the molar concentration as parameter, minimum values are reached at 500°C. The attain of ZnO:F thin films, with a resistivity as low as 7.8×10-3 Ώcm (sheet resistance of 130 Ώ/☐ and film thickness of 600 nm) measured in as-deposited films is reported here for the first time. The concurrent effect of the high molar concentration of the starting solution, the substrate temperature values used, and the ageing of the starting solution, which might cause polymerization of the zinc ions with the fluorine species, enhance the electrical properties. The structure of the films is polycrystalline, with a (002) preferential growth. Molar concentration rules the surface morphology as at low concentration an hexagonal and porous structure is developed changing to a uniform compact and small grain size surface in the films deposited with the high molar concentrations.Keywords: zinc oxide, chemical spray, thin films, TCO
Procedia PDF Downloads 5034033 Selective Oxidation of 6Mn-2Si Advanced High Strength Steels during Intercritical Annealing Treatment
Authors: Maedeh Pourmajidian, Joseph R. McDermid
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Advanced High Strength Steels are revolutionizing both the steel and automotive industries due to their high specific strength and ability to absorb energy during crash events. This allows manufacturers to design vehicles with significantly increased fuel efficiency without compromising passenger safety. To maintain the structural integrity of the fabricated parts, they must be protected from corrosion damage through continuous hot-dip galvanizing process, which is challenging due to selective oxidation of Mn and Si on the surface of this AHSSs. The effects of process atmosphere oxygen partial pressure and small additions of Sn on the selective oxidation of a medium-Mn C-6Mn-2Si advanced high strength steel was investigated. Intercritical annealing heat treatments were carried out at 690˚C in an N2-5%H2 process atmosphere under dew points ranging from –50˚C to +5˚C. Surface oxide chemistries, morphologies, and thicknesses were determined at a variety of length scales by several techniques, including SEM, TEM+EELS, and XPS. TEM observations of the sample cross-sections revealed the transition to internal oxidation at the +5˚C dew point. EELS results suggested that the internal oxides network was composed of a multi-layer oxide structure with varying chemistry from oxide core towards the outer part. The combined effect of employing a known surface active element as a function of process atmosphere on the surface structure development and the possible impact on reactive wetting of the steel substrates by the continuous galvanizing zinc bath will be discussed.Keywords: 3G AHSS, hot-dip galvanizing, oxygen partial pressure, selective oxidation
Procedia PDF Downloads 3984032 Carbon Dioxide Hydrogenation to Methanol over Cu/ZnO-SBA-15 Catalyst: Effect of Metal Loading
Authors: S. F. H. Tasfy, N. A. M. Zabidi, M.-S. Shaharun
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Utilization of CO2 as a carbon source to produce valuable chemicals is one of the important ways to reduce the global warming caused by increasing CO2 in the atmosphere. Supported metal catalysts are crucial for the production of clean and renewable fuels and chemicals from the stable CO2 molecules. The catalytic conversion of CO2 into methanol is recently under increased scrutiny as an opportunity to be used as a low-cost carbon source. Therefore, series of the bimetallic Cu/ZnO-based catalyst supported by SBA-15 were synthesized via impregnation technique with different total metal loading and tested in the catalytic hydrogenation of CO2 to methanol. The morphological and textural properties of the synthesized catalysts were determined by transmission electron microscopy (TEM), temperature programmed desorption, reduction, oxidation and pulse chemisorption (TPDRO), and N2-adsorption. The CO2 hydrogenation reaction was performed in microactivity fixed-bed system at 250 °C, 2.25 MPa, and H2/CO2 ratio of 3. Experimental results showed that the catalytic structure and performance was strongly affected by the loading of the active site. Where, the catalytic activity, methanol selectivity as well as the space-time yield increased with increasing the metal loading until it reaches the maximum values at a metal loading of 15 wt% while further addition of metal inhibits the catalytic performance. The higher catalytic activity of 14 % and methanol selectivity of 92 % were obtained over Cu/ZnO-SBA-15 catalyst with total bimetallic loading of 15 wt%. The excellent performance of 15 wt% Cu/ZnO-SBA-15 catalyst is attributed to the presence of well disperses active sites with small particle size, higher Cu surface area, and lower catalytic reducibility.Keywords: hydrogenation of carbon dioxide, methanol synthesis, metal loading, Cu/ZnO-SBA-15 catalyst
Procedia PDF Downloads 2304031 Sterilization Effects of Low Concentration of Hydrogen Peroxide Solution on 3D Printed Biodegradable Polyurethane Nanocomposite Scaffold for Heart Valve Regeneration
Authors: S. E. Mohmad-Saberi, W. Song, N. Oliver, M. Adrian, T.C. Hsu, A. Darbyshire
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Biodegradable polyurethane (PU) has emerged as a potential material to promote repair and regeneration of damaged/diseased tissues in heart valve regeneration due to its excellent biomechanical profile. Understanding the effects of sterilization on their properties is vital since they are more sensitive and more critical of porous structures compared to bulk ones. In this study, the effects of low concentration of hydrogen peroxide (H₂O₂) solution sterilization has been investigated to determine whether the procedure would be efficient and non-destructive to porous three-dimensional (3D) elastomeric nanocomposite, polyhedral oligomeric silsesquioxane-terminated poly (ethylene-diethylene glycol succinate-sebacate) urea-urethane (POSS-EDSS-PU) scaffold. All the samples were tested for sterility following sterilization using phosphate buffer saline (PBS) as control and 5 % v/v H₂O₂ solution. The samples were incubated in tryptic soy broth for the cultivation of microorganisms under agitation at 37˚C for 72 hours. The effects of the 5 % v/v H₂O₂ solution sterilization were evaluated in terms of morphology, chemical and mechanical properties using scanning electron microscopy (SEM), Fourier transform infrared (FTIR) and tensile tester apparatus. Toxicity effects of the 5 % v/v H₂O₂ solution decontamination were studied by in vitro cytotoxicity test, where the cellular responses of human dermal fibroblast (HDF) were examined. A clear, uncontaminated broth using 5 % v/v H₂O₂ solution method indicated efficient sterilization after 3 days, while the non-sterilized control shows clouding broth indicated contamination. The morphology of 3D POSS-EDSS-PU scaffold appeared to have similar morphology after sterilization with 5 % v/v H₂O₂ solution regarding of pore size and surface. FTIR results show that the sterilized samples and non-sterilized control share the same spectra pattern, confirming no significant alterations over the surface chemistry. For the mechanical properties of the H₂O₂ solution-treated scaffolds, the tensile strain was not significantly decreased, however, become significantly stiffer after the sterilization. No cytotoxic effects were observed after the 5 % v/v H₂O₂ solution sterilization as confirmed by cell viability assessed by Alamar Blue assay. The results suggest that low concentration of 5 % v/v hydrogen peroxide solution can be used as an alternative method for sterilizing biodegradable 3D porous scaffold with micro/nano-architecture without structural deformation. This study provides the understanding of the sterilization effects on biomechanical profile and cell proliferation of 3D POSS-EDSS-PU scaffolds.Keywords: biodegradable, hydrogen peroxide solution, POSS-EDSS-PU, sterilization
Procedia PDF Downloads 1594030 An Experimental Study on Greywater Reuse for Irrigating a Green Wall System
Authors: Mishadi Herath, Amin Talei, Andreas Hermawan, Clarina Chua
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Green walls are vegetated structures on building’s wall that are considered as part of sustainable urban design. They are proved to have many micro-climate benefits such as reduction in indoor temperature, noise attenuation, and improvement in air quality. On the other hand, several studies have also been conducted on potential reuse of greywater in urban water management. Greywater is relatively clean when compared to blackwater; therefore, this study was aimed to assess the potential reuse of it for irrigating a green wall system. In this study, the campus of Monash University Malaysia located in Selangor state was considered as the study site where total 48 samples of greywater were collected from 7 toilets hand-wash and 5 pantries during 3 months period. The samples were tested to characterize the quality of greywater in the study site and compare it with local standard for irrigation water. PH and concentration of heavy metals, nutrients, Total Suspended Solids (TSS), Biochemical Oxygen Demand (BOD), Chemical Oxygen Demand (COD), total Coliform and E.coli were measured. Results showed that greywater could be directly used for irrigation with minimal treatment. Since the effluent of the system was supposed to be drained to stormwater drainage system, the effluent needed to meet certain quality requirement. Therefore, a biofiltration system was proposed to host the green wall plants and also treat the greywater (which is used as irrigation water) to the required level. To assess the performance of the proposed system, an experimental setup consisting of Polyvinyl Chloride (PVC) soil columns with sand-based filter media were prepared. Two different local creeper plants were chosen considering several factors including fast growth, low maintenance requirement, and aesthetic aspects. Three replicates of each plants were used to ensure the validity of the findings. The growth of creeping plants and their survivability was monitored for 6 months while monthly sampling and testing of effluent was conducted to evaluate effluent quality. An analysis was also conducted to estimate the potential cost and benefit of such system considering water and energy saving in the system. Results showed that the proposed system can work efficiently throughout a long period of time with minimal maintenance requirement. Moreover, the biofiltration-green wall system was found to be successful in reusing greywater as irrigating water while the effluent was meeting all the requirements for being drained to stormwater drainage system.Keywords: biofiltration, green wall, greywater, sustainability
Procedia PDF Downloads 2144029 Energy Enterprise Information System for Strategic Decision-Making
Authors: Woosik Jang, Seung H. Han, Seung Won Baek, Chan Young Park
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Natural gas (NG) is a local energy resource that exists in certain countries, and most NG producers operate within unstable governments. Moreover, about 90% of the liquefied natural gas (LNG) market is governed by a small number of international oil companies (IOCs) and national oil companies (NOCs), market entry of second movers is extremely limited. To overcome these barriers, project viability should be assessed based on limited information at the project screening perspective. However, there have been difficulties at the early stages of projects as follows: (1) What factors should be considered? (2) How many experts are needed to make a decision? and (3) How to make an optimal decision with limited information? To answer these questions, this research suggests a LNG project viability assessment model based on the Dempster-Shafer theory (DST). Total of 11 indices for the gas field analysis and 23 indices for the market environment analysis are identified that reflect unique characteristics of LNG industry. Moreover, the proposed model evaluates LNG projects based on questionnaire survey and it provides not only quantified results but also uncertainty level of results based on DST. Consequently, the proposed model as a systematic framework can support the decision-making process from the gas field projects using quantitative results, and it is developed to a stand-alone system to enhance the practical usability. It is expected to improve the decision-making quality and opportunity in LNG projects for enterprise through informed decision.Keywords: project viability, LNG project, enterprise information system, Dempster-Shafer Theory, strategic decision-making
Procedia PDF Downloads 2584028 Methods of Livable Goal-Oriented Master Urban Design: A Case Study on Zibo City
Authors: Xiaoping Zhang, Fengying Yan
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The implementation of the 'Urban Design Management Measures' requires that the master urban design should aim at creating a livable urban space. However, to our best knowledge, the existing researches and practices of master urban design not only focus less on the livable space but also face a number of problems such as paying more attention to the image of the city, ignoring the people-oriented and lacking dynamic continuity. In order to make the master urban design can better guide the construction of city. Firstly, the paper proposes the livable city hierarchy system to meet the needs of different groups of people and then constructs the framework of livable goal-oriented master urban design based on the theory of livable content and the ideological origin of people-oriented. Secondly, the paper takes the master urban design practice of Zibo as a sample and puts forward the design strategy of strengthening the pattern, improve the quality of space, shape the feature, and establish a series of action plans based on the strategy of urban space development. Finally, the paper explores the method system of livable goal-oriented master urban design from the aspects of safety pattern, morphology pattern, neighborhood scale, open space, street space, public interface, style feature, public participation and action plans.Keywords: livable, master urban design, public participation, zibo city
Procedia PDF Downloads 3164027 Study of Therapeutic Potential of Dodonaea Viscosa Against Rheumatoid Arthritis in Collagen Induced Arthritic Mouse Model
Authors: Peter John, Zainab Ali, Attya Bhatti
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Rheumatoid Arthritis (RA) is a systemic autoimmune inflammatory disease that primarily affects the joints. RA is caused in many cases by the interaction between genes and environmental factors, including tobacco, that primarily involves synovial joints. It typically starts in small peripheral joints, is usually symmetric, and progresses to involve proximal joints if left untreated. The prevalence of rheumatoid arthritis varies substantially around the globe, ranging from 0·25% to 1%.3. Rheumatoid arthritis can affect individuals of any age, with an increased incidence in people older than 40 years. Women are affected two to three times more frequently than men. The present work involved evaluating the toxicity and therapeutic potential of Dodonaea viscosa in a collagen-induced arthritic mouse model. Chemical analysis exhibited that Dodonaea viscosa has high levels of beneficial compounds, including phenols, flavonoids, and other phytochemicals. The Dodonaea viscosa showed significant antioxidant, anti-inflammatory, and anti-arthritic potential without toxic effects. Arthritic mice treated with Dodonaea viscosa showed reduced levels of rheumatoid factor and paw edema, while no significant effects on spleen indices and radiological examination of paws were found compared to control untreated arthritic mice. In summary, the Dodonaea viscosa treatment results in improvement in Arthritic Mice Model for which further studies are required.Keywords: rheumatoid arthritis, dodonaea viscisa, anti-inflammatory, anti-rheumatic
Procedia PDF Downloads 234026 Land Cover Classification System for the Estimation of Carbon Storage in Terrestrial Ecosystems
Authors: Lei Zhang
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The carbon cycle greatly influences global change, and the land cover changes contribute to the status and rate of the carbon budget in ecosystems. This paper proposes a land cover classification system for mapping land cover, the national ecological environment assessment, and estimating carbon storage in ecosystems. The classification system consists of basic land cover classes at levels Ⅰ and Ⅱ and auxiliary features at level III. The basic 38 classes characterizing land cover features are derived from 19 criteria referring to composition, structure, pattern, phenology, etc. The basic classes reflect the status of carbon storage in ecosystems. The auxiliary classes at level III complement the attributes of higher levels by 9 criteria. The 5 environmental criteria of temperature, moisture, landform, aspect and slope mainly reflect the potential and intensity of carbon storage in ecosystems. The disturbance of vegetation succession caused by land use type influences the vegetation carbon budget. The other 3 vegetation cover criteria, growth period, and species characteristics further refine the vegetation types. The hierarchical structure of the land cover map (the classes of levels Ⅰ and Ⅱ) is independent of the products of level III, which is helpful for land cover product management and applications. The classification system has been adopted in the Chinese national land cover database for the carbon budget in ecosystems at a 30 m scale.Keywords: classification system, land cover, ecosystem, carbon storage, object based
Procedia PDF Downloads 704025 Consumer’ Knowledge, Attitude and Behavior on Food Safety Issues Related to Pesticide Residues in Cabbage
Authors: Dekie Rawung, Abdul L. Abadi, Toto Himawan, Siegfried Berhimpon
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A case study on consumer' knowledge, attitude, and behavior on food safety issue related to pesticide residues in cabbage was conducted in the area of Manado and Tomohon city, North Sulawesi. A sample of 150 consumers were selected randomly on location (open market and supermarket) while they were purchasing vegetables. The data on consumers’ perception, knowledge, attitude and behavior on food safety issue regarding pesticide residues were collected using a 5-point, two-section Likert-Scale questionnaire, and the relationship of knowledge, attitude, and behavior on food safety issues were analyzed using Structural Equation Modeling (SEM). It was found that, among many food safety issues, the illegal, non-food chemical preservatives were considered the most important one (by more than 35% respondents), followed by high cholesterol content and textile coloring chemical (> 27% respondents). The pesticide residues issue was only in the 4th place. The same results were seen on the issue of quality factors that determine the product selection during purchasing. The pesticide-free and organic products labels were considered much less important quality factors as compared with freshness and nutrition value which were considered the most and the second most important quality factors (almost 65% of respondents). SEM analysis showed that only knowledge and attitude on food safety that had the significant relation (coefficient value of 0.38), whereas those with behaviors were not significant.Keywords: cabbage, consumer, food safety, pesticide residues
Procedia PDF Downloads 4224024 Effect of Provitamin a Biofortified Maize Inclusion Diet on Consumers' Acceptability of Ovambo Chicken Meat
Authors: Feyisayo Odunitan-Wayas, Unathi Kolanisi, Micheal Chimonyo, Muthulisi Siwela
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Consumers’ surveys have indicated low acceptability of provitamin A biofortified maize (PABM), a high vitamin A (HVA) maize in Southern Africa to curb vitamin A deficiency (VAD). Indigenous chickens are reared and consumed by almost all rural households which are the major VAD prone areas in southern Africa. The objective of this study was to determine if HVA diet fed to the Ovambo indigenous chicken breed will influence consumers’ acceptability of the meat. The leg (thigh and drumstick) of the male birds (21 weeks old) were used for the sensory characteristics. 52 consumer panellists evaluated the sensory characteristics on based on a 5-point hedonic scale and preference test. There was no significant difference (P<0.05) in the preference test between the two diets. There were no significant differences (P<0.05) between the diets based on all sensory characteristics. Age and gender of the consumers and their interactions had no effect (P<0.05) on the acceptability and sensory characteristic ratings. It was concluded that indigenous chickens fed provitamin A biofortified maize can be a possible tool for curbing VAD in southern Africa regions where there is low acceptability of the human consumption of provitamin A biofortified maize. It was concluded that PABM diet fed to indigenous chickens will not influence the acceptability of the chicken meat by VAD vulnerable consumers.Keywords: biofortified pro-vitamin a maize, ovambo, chicken meat, sensory characteristics, gender, age
Procedia PDF Downloads 3504023 Novel Development on Orthopedic Prosthesis by Nanocrystalline Hydroxyapatite Nanocomposite Coated on 316 L Stainless Steel
Authors: Neriman Ozada, Ebrahim Karamian, Amirsalar Khandan, Sina Ghafoorpoor Yazdi
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Natural hydroxyapatite, NHA, coatings on the surface of 316 L stainless steel implants has been widely employed in order to achieve better osteoconductivity. For coating, the plasma spraying method is generally used because they ensure adhesion between the coating and the 316 L stainless steel (SS) surface. Some compounds such as zircon (ZrSiO4) is employed as an additive in an attempt to improve HA’s mechanical properties such as wear resistance and hardness. In this study wear resistance has been carried out in different chemical compositions of coating. Therefore, nanocomposites based on NHA containing of 0 wt.%, 5 wt.%, 10 wt.%, and 15 wt.% of zircon were used as a coating on the SS implants. The samples consisted of NHA, derived from calf heated at 850 °C for 3 h. The composite mixture was coated on SS by plasma spray method. The results were estimated using the scanning electron microscopy (SEM), X-ray diffraction (XRD) techniques were utilized to characterize the shape and size of NHA powder. Disc wear test and Vickers hardness were utilized to characterize the coated nanocomposite samples. The prepared NHA powder had nano-scale morphological structure with the mean crystallite size of 30-50 nm in diameter. The wear resistance are almost 320, 380, 415, and 395 m/g and hardness are approximately 376, 391, 420, 410 VHN in ceramic composite materials containing ZrSiO4. The results have been shown that the best wear resistance and hardness occurred in the sample coated by NHA/ZrSiO4 containing of 10 wt.% of zircon.Keywords: zircon, 316 L stainless steel, wear resistance, orthopedic applications, plasma spray
Procedia PDF Downloads 4344022 Impacts of Teachers’ Cluster Model Meeting Intervention on Pupils’ Learning, Academic Achievement and Attitudinal Development in Oyo State, Nigeria
Authors: Olusola Joseph Adesina, Abiodun Ezekiel Adesina
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Efforts at improving the falling standard of education in the country call for the need-based assessment of the primary tier of education in Nigeria. Teachers’ cluster meeting intervention is a step towards enhancing the teachers’ professional competency, efficient and effective pupils’ academic achievement and attitudinal development. The study thus determined the impact of the intervention on pupils’ achievement in Oyo State, Nigeria. Three research questions and four hypotheses guided the study. Pre-test, post-test control group, quasi-experimental design was adopted for the study. Eight intact classes from eight different schools were randomly selected into treatment and control groups. Two response instruments, pupils academic achievement test (PAAT; r = 0.87) and pupils attitude to lesson scale (PALS; r = 0.80) were used for data collection. Mean, standard deviation and analysis of covariance (ANCOVA) were used to analyse the collected data. The results showed that the teachers’ cluster meeting have significant impact on pupils academic achievement (F (1,327) =41.79; p<0.05) and attitudinal development (F (1,327) =26.01; p<0.05) in the core subjects of primary schools in Oyo State, Nigeria. The study therefore recommended among others that teachers’ cluster meeting should be sustained for teachers’ professional development and pupils’ upgradement in the State.Keywords: teachers’ cluster meeting, pupils’ academic achievement, pupils’ attitudinal development, academic achievement
Procedia PDF Downloads 4714021 The Role of Androgens in Prediction of Success in Smoking Cessation in Women
Authors: Michaela Dušková, Kateřina Šimůnková, Martin Hill, Hana Hruškovičová, Hana Pospíšilová, Eva Králíková, Luboslav Stárka
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Smoking represents the most widespread substance dependence in the world. Several studies show the nicotine's ability to alter women hormonal homeostasis. Women smokers have higher testosterone and lower estradiol levels throughout life compared to non-smoker women. We monitored the effect of smoking discontinuation on steroid spectrum with 40 premenopausal and 60 postmenopausal women smokers. These women had been examined before they discontinued smoking and also after 6, 12, 24, and 48 weeks of abstinence. At each examination, blood was collected to determine steroid spectrum (measured by GC-MS), LH, FSH, and SHBG (measured by IRMA). Repeated measures ANOVA model was used for evaluation of the data. The study has been approved by the local Ethics Committee. Given the small number of premenopausal women who endured not to smoke, only the first 6 week period data could be analyzed. A slight increase in androgens after the smoking discontinuation occurred. In postmenopausal women, an increase in testosterone, dihydrotestosterone, dehydroepiandrosterone, and other androgens occurred, too. Nicotine replacement therapy, weight changes, and age does not play any role in the androgen level increase. The higher androgens levels correlated with failure in smoking cessation. Women smokers have higher androgen levels, which might play a role in smoking dependence development. Women successful in smoking cessation, compared to the non-successful ones, have lower androgen levels initially and also after smoking discontinuation. The question is what androgen levels women have before they start smoking.Keywords: addiction, smoking, cessation, androgens
Procedia PDF Downloads 381