Search results for: short fiber reinforced composite
1120 Teacher Education: Teacher Development and Support
Authors: Khadem Hichem
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With the new technology challenges, dynamics and challenges of the contemporary world, most teachers are struggling to maintain effective and successful teaching /learning environment for learners. Teachers as a key to the success of reforms in the educational setting, they must improve their competencies to teach effectively. Many researchers emphasis on the ongoing professional development of the teacher by enhancing their experiences and encouraging their responsibility for learning, and thus promoting self-reliance, collaboration, and reflection. In short, teachers are considered as learners and they need to learn together. The educational system must support, both conceptually and financially, the teachers’ development as lifelong learners Teachers need opportunities to grow in language proficiency and in knowledge. Changing nature of language and culture in the world, all teachers must have opportunities to update their knowledge and practices. Many researchers in the field of foreign or additional languages indicate that teachers keep side by side of effective instructional practices and they need special support with the challenging task of developing and administering proficiency tests to their students. For significant change to occur, each individual teacher’s needs must be addressed. The teacher must be involved experientially in the process of development, since, by itself, knowledge of how to change does not mean change will be initiated. For improvement to occur, new skills have to be guided, practiced, and reflected upon in collaboration with colleagues. Clearly, teachers are at different places developmentally; therefore, allowances for various entry levels and individual differences need to be built into the professional development structure. Objectives must be meaningful to the participant and teacher improvement must be stated terms of student knowledge, student performance, and motivation. The most successful professional development process acknowledges the student-centered nature of good teaching. This paper highlights the importance of teacher professional development process and institutional supports as way to enhance good teaching and learning environment.Keywords: teacher professional development, teacher competencies, institutional support, teacher education
Procedia PDF Downloads 3541119 Child Labor and Injury Occurrence in Nicaragua: A Gender Perspective Analysis
Authors: Cristina Domínguez, Steven N. Cuadra
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Aims: The aims of this study are: 1) to describe the occurrence and estimate the risk of suffering injuries of any kind, especially work-related injuries, in rural children working in agricultural activities and in urban children working on the street 2) to explore factors that might be associated with the occurrence of work-related injuries among child workers such as gender, school attendance, and performance of household chore. Method: We performed a crossectional study among working children in agricultural activities (120) and on the street (108) and in non-working referents (140) in 2019. We investigated self-reported injuries during the last 12 months, with focus on work-related injuries. Incidence rate, rate ratios, and 95% CI were calculated by Poisson regression. Results: Agricultural workers have a higher incidence of work-related injuries (2.1 per 1000 person-days) than children working on the street (1.8 per 1000 person-days). However, when considering girl’s unpaid work at home, girls had higher occurrence. Girls had a 30% increase on the risk of suffering work related injuries compared to boys. Performing household chore and attending school were the major predictors of injury occurrence. Discussion: Our data suggest If such partial and full-time girl’s housework is taken into account, there would be little or no variation between the sexes with regard to injuries occurrence, and the incidence rate of work related injuries among girls could even exceed that of boys A greater understanding of the interaction of factors related to how child workers spend their time, and its impact on children’s health, is needed in order to identify feasible and appropriate strategies to reduce the negative effect of work on children when elimination of child labor is not reachable in the short term. Clearly, gender aspects on child labor may allow for more effective targeting of prevention efforts.Keywords: injuries, child labor, agricultural work, gender
Procedia PDF Downloads 1241118 DFT and SCAPS Analysis of an Efficient Lead-Free Inorganic CsSnI₃ Based Perovskite Solar Cell by Modification of Hole Transporting Layer
Authors: Seyedeh Mozhgan Seyed Talebi, Chih -Hao Lee
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With an abrupt rise in the power conservation efficiency (PCE) of perovskite solar cells (PSCs) within a short span of time, the toxicity of lead was raised as a major hurdle in the path toward their commercialization. In the present research, a systematic investigation of the electrical and optical characteristics of the all-inorganic CsSnI₃ perovskite absorber layer was performed with the Vienna Ab Initio Simulation Package (VASP) using the projector-augmented wave method. The presence of inorganic halide perovskite offers the advantages of enhancing the degradation resistance of the device, reducing the cost of cells, and minimizing the recombination of generated carriers. The simulated standard device using a 1D simulator like solar cell capacitance simulator (SCAPS) version 3308 involves FTO/n-TiO₂/CsSnI₃ Perovskite absorber/Spiro OmeTAD HTL/Au contact layer. The variation in the device design key parameters such as the thickness and defect density of perovskite absorber, hole transport layer and electron transport layer and interfacial defects are examined with their impact on the photovoltaic characteristic parameters. The effect of an increase in operating temperature from 300 K to 400 K on the performance of CsSnI3-based perovskite devices is also investigated. The optimized standard device at room temperature shows the highest PCE of 25.18 % with FF of 75.71 %, Voc of 0.96 V, and Jsc of 34.67 mA/cm². The outcomes and interpretation of different inorganic Cu-based HTLs presence, such as CuSCN, Cu₂O, CuO, CuI, SrCu₂O₂, and CuSbS₂, here represent a critical avenue for the possibility of fabricating high PCE perovskite devices made of stable, low-cost, efficient, safe, and eco-friendly all-inorganic materials like CsSnI₃ perovskite light absorber.Keywords: CsSnI₃, hole transporting layer (HTL), lead-free perovskite solar cell, SCAPS-1D software
Procedia PDF Downloads 871117 Eosinophilic Granulomatosis with Polyangiitis in Pediatrics Patient: A Case Report
Authors: Saboor Saeed, Chunming Jiang
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Eosinophilic Granulomatosis with polyangiitis (EGPA), formerly known as Churg-Strauss syndrome, is a rare systemic vasculitis of small and medium-sized vessels that primarily develops in middle-aged individuals. It is characterized by asthma, blood eosinophilia, and extra pulmonary manifestations. In childhood, EGPA is extremely rare. Pulmonary and cardiac involvement is predominant in pediatric EGPA, and mortality is substantial. Generally, EGPA will develop in three stages: a) The allergic phase is commonly associated with asthma, allergic rhinitis, and sinusitis, b) the eosinophilic phase, in which the main pathology is related to the infiltration of eosinophilic organs, i.e., lung, heart, and gastrointestinal system, c) vasculitis phase involved purpura, peripheral neuropathy, and some constitutional symptoms. The key to the treatment of EGPA lies in the early diagnosis of the disease. Early application of glucocorticoids and immunosuppressants can improve symptoms and the overall prognosis of EGPA. Case Description: We presented a case of an 8-year-old boy with a history of short asthma, marked eosinophilia, and multi-organ involvement. The extremely high eosinophil level in the blood (72.50%) prompted the examination of eosinophilic leukemia before EGPA diagnosis was made. Subsequently, this disease was successfully treated. This case report shows a typical case of CSS in childhood because of the extreme eosinophilia. It emphasizes the importance of EGPA is a life-threatening cause of children's eosinophilia. Conclusion: EGPA in children has unique clinical, imaging, and histological characteristics different from those of adults. In pediatric patients, the development and diagnosis of systemic symptoms are often delayed, mainly occurring in the eosinophilic phase, which will lead to specific manifestations. At the same time, we cannot detect a genetic relationship related to EGPA.Keywords: Churg Strauss syndrome, asthma, vasculitis, hypereosinophilia, eosinophilic granulomatosis polyangiitis
Procedia PDF Downloads 2021116 Tuberculosis (TB) and Lung Cancer
Authors: Asghar Arif
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Lung cancer has been recognized as one of the greatest common cancers, causing the annual mortality rate of about 1.2 million people in the world. Lung cancer is the most prevalent cancer in men and the third-most common cancer among women (after breast and digestive cancers).Recent evidences have shown the inflammatory process as one of the potential factors of cancer. Tuberculosis (TB), pneumonia, and chronic bronchitis are among the most important inflammation-inducing factors in the lungs, among which TB has a more profound role in the emergence of cancer.TB is one of the important mortality factors throughout the world, and 205,000 death cases are reported annually due to this disease. Chronic inflammation and fibrosis due to TB can induce genetic mutation and alternations. Parenchyma tissue of lung is involved in both diseases of TB and lung cancer, and continuous cough in lung cancer, morphological vascular variations, lymphocytosis processes, and generation of immune system mediators such as interleukins, are all among the factors leading to the hypothesis regarding the role of TB in lung cancer Some reports have shown that the induction of necrosis and apoptosis or TB reactivation, especially in patients with immune-deficiency, may result in increasing IL-17 and TNF_α, which will either decrease P53 activity or increase the expression of Bcl-2, decrease Bax-T, and cause the inhibition of caspase-3 expression due to decreasing the expression of mitochondria cytochrome oxidase. It has been also indicated that following the injection of BCG vaccine, the host immune system will be reinforced, and in particular, the rates of gamma interferon, nitric oxide, and interleukin-2 are increased. Therefore, CD4 + lymphocyte function will be improved, and the person will be immune against cancer.Numerous prospective studies have so far been conducted on the role of TB in lung cancer, and it seems that this disease is effective in that particular cancer.One of the main challenges of lung cancer is its correct and timely diagnosis. Unfortunately, clinical symptoms (such as continuous cough, hemoptysis, weight loss, fever, chest pain, dyspnea, and loss of appetite) and radiological images are similar in TB and lung cancer. Therefore, anti-TB drugs are routinely prescribed for the patients in the countries with high prevalence of TB, like Pakistan. Regarding the similarity in clinical symptoms and radiological findings of lung cancer, proper diagnosis is necessary for TB and respiratory infections due to nontuberculousmycobacteria (NTM). Some of the drug resistive TB cases are, in fact, lung cancer or NTM lung infections. Acid-fast staining and histological study of phlegm and bronchial washing, culturing and polymerase chain reaction TB are among the most important solutions for differential diagnosis of these diseases. Briefly, it is assumed that TB is one of the risk factors for cancer. Numerous studies have been conducted in this regard throughout the world, and it has been observed that there is a significant relationship between previous TB infection and lung cancer. However, to prove this hypothesis, further and more extensive studies are required. In addition, as the clinical symptoms and radiological findings of TB, lung cancer, and non-TB mycobacteria lung infections are similar, they can be misdiagnosed as TB.Keywords: TB and lung cancer, TB people, TB servivers, TB and HIV aids
Procedia PDF Downloads 731115 Illegal Anthropogenic Activity Drives Large Mammal Population Declines in an African Protected Area
Authors: Oluseun A. Akinsorotan, Louise K. Gentle, Md. Mofakkarul Islam, Richard W. Yarnell
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High levels of anthropogenic activity such as habitat destruction, poaching and encroachment into natural habitat have resulted in significant global wildlife declines. In order to protect wildlife, many protected areas such as national parks have been created. However, it is argued that many protected areas are only protected in name and are often exposed to continued, and often illegal, anthropogenic pressure. In West African protected areas, declines of large mammals have been documented between 1962 and 2008. This study aimed to produce occupancy estimates of the remaining large mammal fauna in the third largest National Park in Nigeria, Old Oyo, and to compare the estimates with historic estimates while also attempting to quantify levels of illegal anthropogenic activity using a multi-disciplinary approach. Large mammal populations and levels of illegal anthropogenic activity were assessed using empirical field data (camera trapping and transect surveys) in combination with data from questionnaires completed by local villagers and park rangers. Four of the historically recorded species in the park, lion (Panthera leo), hunting dog (Lycaon pictus), elephant (Loxodonta africana) and buffalo (Syncerus caffer) were not detected during field studies nor were they reported by respondents. In addition, occupancy estimates of hunters and illegal grazers were higher than the majority of large mammal species inside the park. This finding was reinforced by responses from the villagers and rangers who’s perception was that large mammal densities in the park were declining, and that a large proportion of the local people were entering the park to hunt wild animals and graze their domestic livestock. Our findings also suggest that widespread poverty and a lack of alternative livelihood opportunities, culture of consuming bushmeat, lack of education and awareness of the value of protected areas, and weak law enforcement are some of the reasons for the illegal activity. Law enforcement authorities were often constrained by insufficient on-site personnel and a lack of modern equipment and infrastructure to deter illegal activities. We conclude that there is a need to address the issue of illegal hunting and livestock grazing, via provision of alternative livelihoods, in combination with community outreach programmes that aim to improve conservation education and awareness and develop the capacity of the conservation authorities in order to achieve conservation goals. Our findings have implications for the conservation management of all protected areas that are available for exploitation by local communities.Keywords: camera trapping, conservation, extirpation, illegal grazing, large mammals, national park, occupancy estimates, poaching
Procedia PDF Downloads 2961114 A Deep Learning Approach to Real Time and Robust Vehicular Traffic Prediction
Authors: Bikis Muhammed, Sehra Sedigh Sarvestani, Ali R. Hurson, Lasanthi Gamage
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Vehicular traffic events have overly complex spatial correlations and temporal interdependencies and are also influenced by environmental events such as weather conditions. To capture these spatial and temporal interdependencies and make more realistic vehicular traffic predictions, graph neural networks (GNN) based traffic prediction models have been extensively utilized due to their capability of capturing non-Euclidean spatial correlation very effectively. However, most of the already existing GNN-based traffic prediction models have some limitations during learning complex and dynamic spatial and temporal patterns due to the following missing factors. First, most GNN-based traffic prediction models have used static distance or sometimes haversine distance mechanisms between spatially separated traffic observations to estimate spatial correlation. Secondly, most GNN-based traffic prediction models have not incorporated environmental events that have a major impact on the normal traffic states. Finally, most of the GNN-based models did not use an attention mechanism to focus on only important traffic observations. The objective of this paper is to study and make real-time vehicular traffic predictions while incorporating the effect of weather conditions. To fill the previously mentioned gaps, our prediction model uses a real-time driving distance between sensors to build a distance matrix or spatial adjacency matrix and capture spatial correlation. In addition, our prediction model considers the effect of six types of weather conditions and has an attention mechanism in both spatial and temporal data aggregation. Our prediction model efficiently captures the spatial and temporal correlation between traffic events, and it relies on the graph attention network (GAT) and Bidirectional bidirectional long short-term memory (Bi-LSTM) plus attention layers and is called GAT-BILSTMA.Keywords: deep learning, real time prediction, GAT, Bi-LSTM, attention
Procedia PDF Downloads 731113 Genome Sequencing and Analysis of the Spontaneous Nanosilver Resistant Bacterium Proteus mirabilis Strain scdr1
Authors: Amr Saeb, Khalid Al-Rubeaan, Mohamed Abouelhoda, Manojkumar Selvaraju, Hamsa Tayeb
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Background: P. mirabilis is a common uropathogenic bacterium that can cause major complications in patients with long-standing indwelling catheters or patients with urinary tract anomalies. In addition, P. mirabilis is a common cause of chronic osteomyelitis in diabetic foot ulcer (DFU) patients. Methodology: P. mirabilis SCDR1 was isolated from a diabetic ulcer patient. We examined P. mirabilis SCDR1 levels of resistance against nano-silver colloids, the commercial nano-silver and silver containing bandages and commonly used antibiotics. We utilized next generation sequencing techniques (NGS), bioinformatics, phylogenetic analysis and pathogenomics in the identification and characterization of the infectious pathogen. Results: P. mirabilis SCDR1 is a multi-drug resistant isolate that also showed high levels of resistance against nano-silver colloids, nano-silver chitosan composite and the commercially available nano-silver and silver bandages. The P. mirabilis-SCDR1 genome size is 3,815,621 bp with G+C content of 38.44%. P. mirabilis-SCDR1 genome contains a total of 3,533 genes, 3,414 coding DNA sequence genes, 11, 10, 18 rRNAs (5S, 16S, and 23S), and 76 tRNAs. Our isolate contains all the required pathogenicity and virulence factors to establish a successful infection. P. mirabilis SCDR1 isolate is a potential virulent pathogen that despite its original isolation site, wound, it can establish kidney infection and its associated complications. P. mirabilis SCDR1 contains several mechanisms for antibiotics and metals resistance including, biofilm formation, swarming mobility, efflux systems, and enzymatic detoxification. Conclusion: P. mirabilis SCDR1 is the spontaneous nano-silver resistant bacterial strain. P. mirabilis SCDR1 strain contains all reported pathogenic and virulence factors characteristic for the species. In addition, it possesses several mechanisms that may lead to the observed nano-silver resistance.Keywords: Proteus mirabilis, multi-drug resistance, silver nanoparticles, resistance, next generation sequencing techniques, genome analysis, bioinformatics, phylogeny, pathogenomics, diabetic foot ulcer, xenobiotics, multidrug resistance efflux, biofilm formation, swarming mobility, resistome, glutathione S-transferase, copper/silver efflux system, altruism
Procedia PDF Downloads 3351112 Anterior Tooth Misalignment: Orthodontics or Restorative Treatment
Authors: Maryam Firouzmandi, Moosa Miri
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Smile is considered to be one of the most effective methods of influencing people. Increasing numbers of patients are requesting cosmetic dental procedures to achieve the perfect smile. Based on the patient’s age, oral and facial characteristics, and the dentist’s expertise, different concepts of treatment would be available. Orthodontics is the most conservative and the ideal treatment alternative for crowded anterior teeth; however, it may be rejected by patients due to occupational limitations of time, physical discomfort including pain and functional limitations, psychological discomfort, and appearance during treatment. In addition, orthodontic treatment will not resolve deficits of contour and color of the anterior teeth. In consequence, patients may demand restorative techniques to resolve their anterior mal-alignment instead, often called "instant orthodontics". Following its introduction, however, adhesive dentistry has suffered at times from overuse. Creating short-term attractive smiles at the expense of long-term dental health and optimal tooth biomechanics by using cosmetic techniques should not be considered an ethical approach. The objective of this narrative review was to investigate the literature for guidelines with regard to decision making and treatment planning for anterior tooth mal-alignment. In this regard, indications of orthodontic, restorative, combination of both treatments, and adjunctive periodontal surgery were discussed in clinical cases to achieve a proportional smile. Restorative modalities would include disking, cosmetic contouring, veneers, and crowns and were compared with limited or comprehensive orthodontic options. A rapid review was also presented on pros and cons of snap on smile to mask malalignments. Diagnostic tools such as mock up, wax up, and digital smile design were also considered to achieve more conservative and functional treatments with respect to biologic factors.Keywords: crowding, misalignment, veneer, crown, orthodontics
Procedia PDF Downloads 1161111 Photoinduced Energy and Charge Transfer in InP Quantum Dots-Polymer/Metal Composites for Optoelectronic Devices
Authors: Akanksha Singh, Mahesh Kumar, Shailesh N. Sharma
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Semiconductor quantum dots (QDs) such as CdSe, CdS, InP, etc. have gained significant interest in the recent years due to its application in various fields such as LEDs, solar cells, lasers, biological markers, etc. The interesting feature of the QDs is their tunable band gap. The size of the QDs can be easily varied by varying the synthesis parameters which change the band gap. One of the limitations with II-VI semiconductor QDs is their biological application. The use of cadmium makes them unsuitable for biological applications. III-V QD such as InP overcomes this problem as they are structurally robust because of the covalent bonds which do not allow the ions to leak. Also, InP QDs has large Bohr radii which increase the window for the quantum confinement effect. The synthesis of InP QDs is difficult and time consuming. Authors have synthesized InP using a novel, quick synthesis method which utilizes trioctylphosphine as a source of phosphorus. In this work, authors have made InP composites with P3HT(Poly(3-hexylthiophene-2,5-diyl))polymer(organic-inorganic hybrid material) and gold nanoparticles(metal-semiconductor composites). InP-P3HT shows FRET phenomenon whereas InP-Au shows charge transfer mechanism. The synthesized InP QDs has an absorption band at 397 nm and PL peak position at 491 nm. The band gap of the InP QDs is 2.46 eV as compared to the bulk band gap of InP i.e. 1.35 eV. The average size of the QDs is around 3-4 nm. In order to protect the InP core, a shell of wide band gap material i.e. ZnS is coated on the top of InP core. InP-P3HT composites were made in order to study the charge transfer/energy transfer phenomenon between them. On adding aliquots of P3HT to InP QDs solution, the P3HT PL increases which can be attributed to the dominance of Förster energy transfer between InP QDs (donor) P3HT polymer (acceptor). There is a significant spectral overlap between the PL spectra of InP QDs and absorbance spectra of P3HT. But in the case of InP-Au nanocomposites, significant charge transfer was seen from InP QDs to Au NPs. When aliquots of Au NPs were added to InP QDs, a decrease in the PL of the InP QDs was observed. This is due to the charge transfer from the InP QDs to the Au NPs. In the case of metal semiconductor composites, the enhancement and quenching of QDs depend on the size of the QD and the distance between the QD and the metal NP. These two composites have different phenomenon between donor and acceptor and hence can be utilized for two different applications. The InP-P3HT composite can be utilized for LED devices due to enhancement in the PL emission (FRET). The InP-Au can be utilized efficiently for photovoltaic application owing to the successful charge transfer between InP-Au NPs.Keywords: charge transfer, FRET, gold nanoparticles, InP quantum dots
Procedia PDF Downloads 1481110 Selection of Social and Sustainability Criteria for Public Investment Project Evaluation in Developing Countries
Authors: Pintip Vajarothai, Saad Al-Jibouri, Johannes I. M. Halman
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Public investment projects are primarily aimed at achieving development strategies to increase national economies of scale and overall improvement in a country. However, experience shows that public projects, particularly in developing countries, struggle or fail to fulfill the immediate needs of local communities. In many cases, the reason for that is that projects are selected in a subjective manner and that a major part of the problem is related to the evaluation criteria and techniques used. The evaluation process is often based on a broad strategic economic effects rather than real benefits of projects to society or on the various needs from different levels (e.g. national, regional, local) and conditions (e.g. long-term and short-term requirements). In this paper, an extensive literature review of the types of criteria used in the past by various researchers in project evaluation and selection process is carried out and the effectiveness of such criteria and techniques is discussed. The paper proposes substitute social and project sustainability criteria to improve the conditions of local people and in particular the disadvantaged groups of the communities. Furthermore, it puts forward a way for modelling the interaction between the selected criteria and the achievement of the social goals of the affected community groups. The described work is part of developing a broader decision model for public investment project selection by integrating various aspects and techniques into a practical methodology. The paper uses Thailand as a case to review what and how the various evaluation techniques are currently used and how to improve the project evaluation and selection process related to social and sustainability issues in the country. The paper also uses an example to demonstrates how to test the feasibility of various criteria and how to model the interaction between projects and communities. The proposed model could be applied to other developing and developed countries in the project evaluation and selection process to improve its effectiveness in the long run.Keywords: evaluation criteria, developing countries, public investment, project selection methodology
Procedia PDF Downloads 2771109 The Impact of Rapid Urbanisation on Public Transport Systems in the Gauteng Region of South Africa
Authors: J. Chakwizira, P. Bikam, T. A. Adeboyejo
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This paper seeks to illustrate the impact of rapid urbanization (in terms of both increase in people and vehicles) in the Gauteng region (which includes Johannesburg, Pretoria and Ekurhuleni). The impact that existing transport systems and options place on the capacity of residents from low income areas to travel and conduct various socio-economic activities is discussed. The findings are drawn from a 2013 analysis of a random transport household survey of 1550 households carried out in Gauteng province. 91.4% of the study respondents had access to public transport, while 8.6% had no access to public transport. Of the 91.4% who used public transport, the main reason used to explain this state of affairs was that it was affordable (54.3%), convenient (15.9%), Accessible (11.9%), lack of alternatives (6.4%) and reliable at 4.1%. Recommendations advanced revolve around the need to reverse land use and transportation effects of apartheid planning, growing and developing a sustainable critical mass of public transport interventions supported by appropriate transport systems that are environmentally sustainable through proper governance. 38.5% of the respondents indicated that developing compact, smart and integrated urban land spaces was key to reducing travel challenges in the study area. 23.4% indicated that the introduction and upgrading of BRT buses to cover all areas in the study area was a step in the right direction because it has great potential in shifting travel patterns to favor public modes of transport. 15.1% indicated that all open spaces should be developed so that fragmentation of land uses can be addressed. This would help to fight disconnected and fragmented space and trip making challenges in Gauteng. 13.4% indicated that improving the metro rail services was critical since this is a mass mover of commuters. 9.6% of the respondents highlighted that the bus subsidy policy has to be retained in the short to medium term since the spatial mismatches and challenges created by apartheid are yet to be fully reversed.Keywords: urbanisation, population, public, transport systems, Gauteng
Procedia PDF Downloads 2881108 Spawning Induction and Early Larval Development of the Giant Reef Clam Periglypta multicostata (Sowerby, 1835) under Controlled Conditions
Authors: Jose Melena, Rosa Santander, Tanya Gonzalez, Richard Duque, Juan Illanes
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Ecuador is one of the countries with the greatest aquatic biodiversity worldwide. In particular, there are at least a dozen native marine species with great aquaculture potential locally. This research concerns one of those species. It has proposed to implement experimental protocols in order to induce spawning and to generate the early larval development of the giant reef clam P. multicostata under controlled conditions. Bioassays were carried out with one adult batch (n= 8) with an average valvar length of 118,4 ± 5,8 mm, which were collected near of the Puerto Santa Rosa (2° 12' 30'' S, 80° 58' 28'' W), Santa Elena Province. During a short acclimation stage, the eight adults of giant reef clam P. multicostata were exposed to thermal stress. Briefly, the experimental protocol for spawning induction was based on the application of 20°C for 1 h and 30°C for 1 h on P. multicostata broodstock at least three consecutive times by one day. After spawning, collected sexual material was released for external fertilization process. After the delivery of gametes, it was achieved 3,25 × 10⁶ viable zygotes. As results, fertilized eggs had 56 µm diameter; while first and second cell divisions were observed to 2,5 h post-fertilization, with individual average length of 68 ± 5 µm and polar body. Latter cell divisions, including gastrula stage, appeared at 9 h post-fertilization, with individual average length of 73 ± 4 µm and trochophore stage at 15 h post-fertilization with individual average length of 75 ± 4 µm. In addition, veliger stage was registered at 20 h post-fertilization with individual average length of 82 ± 6 µm. Umboned larvae appeared at day 8 post-fertilization, with individual average length of 148 ± 6 µm. These pioneering results worldwide can strengthen the local conservation process of the overexploited P. multicostata and to encourage its production for commercial purposes.Keywords: Ecuador, larval development, Periglypta multicostata, spawning induction
Procedia PDF Downloads 1361107 Economic Analysis of Rainwater Harvesting Systems for Dairy Cattle
Authors: Sandra Cecilia Muhirirwe, Bart Van Der Bruggen, Violet Kisakye
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Economic analysis of Rainwater harvesting (RWH) systems is vital in search of a cost-effective solution to water unreliability, especially in low-income countries. There is little literature focusing on the financial aspects of RWH for dairy farmers. The main purpose was to assess the economic viability of rainwater harvesting for diary framers in the Rwenzori region. The study focused on the use of rainwater harvesting systems from the rooftop and collection in above surface tanks. Daily rainfall time series for 12 years was obtained across nine gauging stations. The daily water balance equation was used for optimal sizing of the tank. Economic analysis of the investment was carried out based on the life cycle costs and the accruing benefits for the period of 15 years. Roof areas were varied from 75m2 as the minimum required area to 500m2 while maintaining the same number of cattle and keeping the daily water demand constant. The results show that the required rainwater tank sizes are very large and may be impractical to install due to the strongly varying terrain and the initial cost of investment. In all districts, there is a significant reduction of the volume of the required tank with an increasing collection area. The results further show that increasing the collection area has a minor effect on reducing the required tank size. Generally, for all rainfall areas, the reliability increases with an increase in the roof area. The results indicate that 100% reliability can only be realized with very large collection areas that are impractical to install. The estimated benefits outweigh the cost of investment. The Present Net Value shows that the investment is economically viable and investment with a short payback of a maximum of 3 years for all the time series in the study area.Keywords: dairy cattle, optimisation, rainwater harvesting, economic analysis
Procedia PDF Downloads 2051106 Comparison of Gestational Diabetes Influence on the Ultrastructure of Rectus Abdominis Muscle in Women and Rats
Authors: Giovana Vesentini, Fernanda Piculo, Gabriela Marini, Debora Damasceno, Angelica Barbosa, Selma Martheus, Marilza Rudge
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Problem statement: Skeletal muscle is highly adaptable, muscle fiber composition and size can respond to a variety of stimuli, such physiologic, as pregnancy, and metabolic abnormalities, as Diabetes mellitus. This study aimed to analyze the effects of pregnancy-associated diabetes on the rectus abdominis muscle (RA), and to compare this changes in rats and women. Methods: Female Wistar rats were maintained under controlled conditions and distributed in Pregnant (P) and Long-term mild pregnant diabetic (LTMd) (n=3 r/group). Diabetes in rats was induced by streptozotocin (100mg/Kg, sc) on the first day of life, for a hyperglycemic state between 120-300 mg/dL in adult life. Female rats were mated overnight, at day 21 of pregnancy were anesthetized, and killed for the harvesting of maternal RA. Pregnant women who attended the Diabetes Prenatal Care Clinic of Botucatu Medical School were distributed in Pregnant non-diabetic (Pnd) and Gestational Diabetic (GDM) (n=3 w/group). The diagnosis of GDM was established according to ADA’s criteria (2016). The harvesting of RA was during the cesarean section. Transversal cross-sections of the RA of both women and rats were analyzed by transmission electron microscopy. All procedures were approved by the Ethics Committee on Animal Experiments of the Botucatu Medical School (Protocol Number 1003/2013) and by the Botucatu Medical School Ethical Committee for Human Research in Medical Sciences (CAAE: 41570815.0.0000.5411). Results: The photomicrographs of the RA of rats revealed disorganized Z lines, thinning sarcomeres, and a usual quantity of intermyofibrillar mitochondria in the P group. The LTMd group showed swollen sarcoplasmic reticulum, dilated T tubes and areas with sarcomere disruption. The ultrastructural analysis of Pnd non-diabetic women in the RA showed well-organized myofibrils forming intact sarcomeres, organized Z lines and a normal distribution of intermyofibrillar mitochondria. The GDM group revealed increase in intermyofibrillar mitochondria, areas with sarcomere disruption and increased lipid droplets. Conclusion: Pregnancy and diabetes induce adaptations in the ultrastructure of the rectus abdominis muscle for both women and rats, changing the architectural design of these tissues. However, in rats these changes are more severe maybe because, besides the high blood glucose levels, the quadrupedal animal may suffer an excessive mechanical tension during pregnancy by gravity. Probably, these findings may suggest that these alterations are a risk factor that contributes to the development of muscle dysfunction in women with GDM and may motivate treatment strategies in these patients.Keywords: gestational diabetes, muscle dysfunction, pregnancy, rectus abdominis
Procedia PDF Downloads 2941105 Comparative Analysis of Short and Long Term Salt Stress on the Photosynthetic Apparatus and Chloroplast Ultrastructure of Thellungiella salsuginea
Authors: Rahma Goussi, Walid Derbali, Arafet Manaa, Simone Cantamessa, Graziella Berta, Chedly Abdelly, Roberto Barbato
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Salinity is one of the most important abiotic affecting plant growth and productivity worldwide. Photosynthesis, together with cell growth, is among the primary processes to be affected by salinity. Here, we report the effects of salinity stress on the primary processes of photosynthesis in a model halophyte Thellungiella Salsuginea. Plants were cultivated in hydroponic system with different NaCl concentrations (0, 100, 200 and 400 mM) during 2 weeks. The obtained results showed an obvious change in the photosynthetic efficiency of photosystem I (PSI) and phostosytem II (PSII), related to NaCl concentration supplemented to the medium and the stress duration considered. With moderate salinity (100 and 200 mM NaCl), no significant variation was observed in photosynthetic parameters of PSI and PSII and Chl fluorescence whatever the time of stress application. Also, the photosynthesis apparatus Fo, Fm and Fv fluorescence, as well as Fv/Fm were not affected by salt stress. While a significant decrease was observed on quantum yields Y(I), Y(II) and electron transport rate ETR(I), ETR(II) under high salt treatment (400 mM NaCl) with prolonged period (15 days). This reduction is quantitatively compensated by a corresponding increase of energy dissipation Y(NPQ) and a progressive decrease in Fv/Fm under salt treatment. The intensity of the OJIP fluorescence transient decreased with increase in NaCl concentration, with a major effect observed during prolonged period of salt stress. Ultrastructural analysis with Light Microscopy and Transmission Electron Microscopy of T. salsuginea chloroplasts showed some cellular changes, such as the shape of the mesophyll cells and number of chloroplast/cell only under higher NaCl concentration. Salt-stress caused the swelling of thylakoids in T. Salsuginea mesophyll with more accumulation of starch as compared to control plant.Keywords: fluorescence, halophyte, photosynthesis, salt stress
Procedia PDF Downloads 3761104 Optimal Tamping for Railway Tracks, Reducing Railway Maintenance Expenditures by the Use of Integer Programming
Authors: Rui Li, Min Wen, Kim Bang Salling
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For the modern railways, maintenance is critical for ensuring safety, train punctuality and overall capacity utilization. The cost of railway maintenance in Europe is high, on average between 30,000 – 100,000 Euros per kilometer per year. In order to reduce such maintenance expenditures, this paper presents a mixed 0-1 linear mathematical model designed to optimize the predictive railway tamping activities for ballast track in the planning horizon of three to four years. The objective function is to minimize the tamping machine actual costs. The approach of the research is using the simple dynamic model for modelling condition-based tamping process and the solution method for finding optimal condition-based tamping schedule. Seven technical and practical aspects are taken into account to schedule tamping: (1) track degradation of the standard deviation of the longitudinal level over time; (2) track geometrical alignment; (3) track quality thresholds based on the train speed limits; (4) the dependency of the track quality recovery on the track quality after tamping operation; (5) Tamping machine operation practices (6) tamping budgets and (7) differentiating the open track from the station sections. A Danish railway track between Odense and Fredericia with 42.6 km of length is applied for a time period of three and four years in the proposed maintenance model. The generated tamping schedule is reasonable and robust. Based on the result from the Danish railway corridor, the total costs can be reduced significantly (50%) than the previous model which is based on optimizing the number of tamping. The different maintenance strategies have been discussed in the paper. The analysis from the results obtained from the model also shows a longer period of predictive tamping planning has more optimal scheduling of maintenance actions than continuous short term preventive maintenance, namely yearly condition-based planning.Keywords: integer programming, railway tamping, predictive maintenance model, preventive condition-based maintenance
Procedia PDF Downloads 4471103 A Finite Element Analysis of Hexagonal Double-Arrowhead Auxetic Structure with Enhanced Energy Absorption Characteristics and Stiffness
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Auxetic materials, as an emerging artificial designed metamaterial has attracted growing attention due to their promising negative Poisson’s ratio behaviors and tunable properties. The conventional auxetic lattice structures for which the deformation process is governed by a bending-dominated mechanism have faced the limitation of poor mechanical performance for many potential engineering applications. Recently, both load-bearing and energy absorption capabilities have become a crucial consideration in auxetic structure design. This study reports the finite element analysis of a class of hexagonal double-arrowhead auxetic structures with enhanced stiffness and energy absorption performance. The structure design was developed by extending the traditional double-arrowhead honeycomb to a hexagon frame, the stretching-dominated deformation mechanism was determined according to Maxwell’s stability criterion. The finite element (FE) models of 2D lattice structures established with stainless steel material were analyzed in ABAQUS/Standard for predicting in-plane structural deformation mechanism, failure process, and compressive elastic properties. Based on the computational simulation, the parametric analysis was studied to investigate the effect of the structural parameters on Poisson’s ratio and mechanical properties. The geometrical optimization was then implemented to achieve the optimal Poisson’s ratio for the maximum specific energy absorption. In addition, the optimized 2D lattice structure was correspondingly converted into a 3D geometry configuration by using the orthogonally splicing method. The numerical results of 2D and 3D structures under compressive quasi-static loading conditions were compared separately with the traditional double-arrowhead re-entrant honeycomb in terms of specific Young's moduli, Poisson's ratios, and specified energy absorption. As a result, the energy absorption capability and stiffness are significantly reinforced with a wide range of Poisson’s ratio compared to traditional double-arrowhead re-entrant honeycomb. The auxetic behaviors, energy absorption capability, and yield strength of the proposed structure are adjustable with different combinations of joint angle, struts thickness, and the length-width ratio of the representative unit cell. The numerical prediction in this study suggests the proposed concept of hexagonal double-arrowhead structure could be a suitable candidate for the energy absorption applications with a constant request of load-bearing capacity. For future research, experimental analysis is required for the validation of the numerical simulation.Keywords: auxetic, energy absorption capacity, finite element analysis, negative Poisson's ratio, re-entrant hexagonal honeycomb
Procedia PDF Downloads 881102 Passively Q-Switched 914 nm Microchip Laser for LIDAR Systems
Authors: Marco Naegele, Klaus Stoppel, Thomas Dekorsy
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Passively Q-switched microchip lasers enable the great potential for sophisticated LiDAR systems due to their compact overall system design, excellent beam quality, and scalable pulse energies. However, many near-infrared solid-state lasers show emitting wavelengths > 1000 nm, which are not compatible with state-of-the-art silicon detectors. Here we demonstrate a passively Q-switched microchip laser operating at 914 nm. The microchip laser consists of a 3 mm long Nd:YVO₄ crystal as a gain medium, while Cr⁴⁺:YAG with an initial transmission of 98% is used as a saturable absorber. Quasi-continuous pumping enables single pulse operation, and low duty cycles ensure low overall heat generation and power consumption. Thus, thermally induced instabilities are minimized, and operation without active cooling is possible while ambient temperature changes are compensated by adjustment of the pump laser current only. Single-emitter diode pumping at 808 nm leads to a compact overall system design and robust setup. Utilization of a microchip cavity approach ensures single-longitudinal mode operation with spectral bandwidths in the picometer regime and results in short laser pulses with pulse durations below 10 ns. Beam quality measurements reveal an almost diffraction-limited beam and enable conclusions concerning the thermal lens, which is essential to stabilize the plane-plane resonator. A 7% output coupler transmissivity is used to generate pulses with energies in the microjoule regime and peak powers of more than 600 W. Long-term pulse duration, pulse energy, central wavelength, and spectral bandwidth measurements emphasize the excellent system stability and facilitate the utilization of this laser in the context of a LiDAR system.Keywords: diode-pumping, LiDAR system, microchip laser, Nd:YVO4 laser, passively Q-switched
Procedia PDF Downloads 1301101 The Online Power of Values: Adolescents’ Values as Predicting Factors of Their Online Bystanders’ Behavior While Witnessing Cyberbullying
Authors: Sharon Cayzer-Haller, Shir Ginosar-Yaari, Ariel Knafo-Noam
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The 21st century emerged as the digital century, and it is marked by a wide range of technological developments and changes, followed by potential changes in human communication skills. This technological revolution has changed human means of communication in many different ways: children and adolescents are spending much of their time in front of screens, participating in all sorts of online activities (even more so since the outbreak of COVID-19). The current study focuses on the role of values in adolescents' online bystanders' behavior. Values are cognitive, abstract representations of desirable goals that motivate behavior, and we hypothesized finding significant associations between specific values and differential online bystanders' feelings and behavior. Data was collected through online questionnaires that measured the participants' values, using Schwartz's short version of the Portrait Values Questionnaire (Schwartz, 2012). Participants’ online behavior was assessed in a questionnaire addressing reactions to situations of cyber shaming and cyberbullying, and specifically positive feelings and pro-social behavior (e.g., more supportive reactions) toward the victims, as opposed to different offensive behavioral reactions (such as laughing at the victim or ignoring the situation). Participants were recruited with a commercial research panel company, and 308 Israeli adolescents' values and online behavior were examined (mean age 15.2). As hypothesized, results show significant associations between self-transcendence values (universalism and benevolence) and conservation values (conformity, tradition, and security). These two groups of values were positively correlated with pro-social bystanders' feelings and behavior. On the opposite side of the values scale, the value of power was negatively associated with the participants' pro-social behavior, and positively associated with offensive behavioral reactions. Further research is needed, but we conclude that values serve as crucial guiding factors in directing adolescents' online feelings and behavior.Keywords: adolescents, values, cyberbullying, online behavior, power
Procedia PDF Downloads 661100 Rationale of Eye Pupillary Diameter for the UV Protection for Sunglasses
Authors: Liliane Ventura, Mauro Masili
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Ultraviolet (UV) protection is critical for sunglasses, and mydriasis, as well as miosis, are relevant parameters to consider. The literature reports that for sunglasses, ultraviolet protection is critical because sunglasses can cause the opposite effect if the lenses do not provide adequate UV protection due to the greater dilation of the pupil when wearing sunglasses. However, the scientific literature does not properly quantify to support this rationale. The reasoning may be misleading by ignoring not only the inherent absorption of UV by the sunglass lens materials but also by ignoring the absorption of the anterior structures of the eye, i.e., the cornea and aqueous humor. Therefore, we estimate the pupil diameter and calculate the solar ultraviolet influx through the pupil of the human eye for two situations of an individual wearing and not wearing sunglasses. We quantify the dilation of the pupil as a function of the luminance of the surrounding. Therefore, we calculate the influx of solar UV through the pupil of the eye for two situations for an individual wearing sunglass and for the eyes free of shade. A typical boundary condition for the calculation is an individual in an upright position wearing sunglasses, staring at the horizon as if the sun is in the zenith. The calculation was done for the latitude of the geographic center of the state of São Paulo (-22º04'11.8'' S) from sunrise to sunset. A model from the literature is used for determining the sky luminance. The initial approach is to obtain pupil diameter as a function of luminance. Therefore, as a preliminary result, we calculate the pupil diameter as a function of the time of day, as the sun moves, for a particular day of the year. The working range for luminance is daylight (10⁻⁴ – 10⁵ cd/m²). We are able to show how the pupil adjusts to brightness change (~2 - ~7.8 mm). At noon, with the sun higher, the direct incidence of light on the pupil is lower if compared to mid-morning or mid-afternoon, when the sun strikes more directly into the eye. Thus, the pupil is larger at midday. As expected, the two situations have opposite behaviors since higher luminance implies a smaller pupil. With these results, we can progress in the short term to obtain the transmittance spectra of sunglasses samples and quantify how light attenuation provided by the spectacles affects pupil diameter.Keywords: sunglasses, UV protection, pupil diameter, solar irradiance, luminance
Procedia PDF Downloads 831099 One-Class Classification Approach Using Fukunaga-Koontz Transform and Selective Multiple Kernel Learning
Authors: Abdullah Bal
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This paper presents a one-class classification (OCC) technique based on Fukunaga-Koontz Transform (FKT) for binary classification problems. The FKT is originally a powerful tool to feature selection and ordering for two-class problems. To utilize the standard FKT for data domain description problem (i.e., one-class classification), in this paper, a set of non-class samples which exist outside of positive class (target class) describing boundary formed with limited training data has been constructed synthetically. The tunnel-like decision boundary around upper and lower border of target class samples has been designed using statistical properties of feature vectors belonging to the training data. To capture higher order of statistics of data and increase discrimination ability, the proposed method, termed one-class FKT (OC-FKT), has been extended to its nonlinear version via kernel machines and referred as OC-KFKT for short. Multiple kernel learning (MKL) is a favorable family of machine learning such that tries to find an optimal combination of a set of sub-kernels to achieve a better result. However, the discriminative ability of some of the base kernels may be low and the OC-KFKT designed by this type of kernels leads to unsatisfactory classification performance. To address this problem, the quality of sub-kernels should be evaluated, and the weak kernels must be discarded before the final decision making process. MKL/OC-FKT and selective MKL/OC-FKT frameworks have been designed stimulated by ensemble learning (EL) to weight and then select the sub-classifiers using the discriminability and diversities measured by eigenvalue ratios. The eigenvalue ratios have been assessed based on their regions on the FKT subspaces. The comparative experiments, performed on various low and high dimensional data, against state-of-the-art algorithms confirm the effectiveness of our techniques, especially in case of small sample size (SSS) conditions.Keywords: ensemble methods, fukunaga-koontz transform, kernel-based methods, multiple kernel learning, one-class classification
Procedia PDF Downloads 241098 A Modernist Project: An Analysis on Dupont’s Translations of Faulkner’s Works
Authors: Edilei Reis, Jose Carlos Felix
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This paper explores Waldir Dupont’s translations of William Faulkner’s novels to Brazilian Portuguese language in order to comprehend how his translation project regarding Faulkner’s works has addressed modernist traits of the novelist fiction, particularly the ambivalence of language, multiple and fragmented points of view and syntax. Wladir Dupont (1939-2014) was a prolific Brazilian journalist who benefitted from his experiences as an international correspondent living abroad (EUA and Mexico) to become an acclaimed translator later in life. He received a Jabuiti Award (Brazilian most prestigious literary award) for his translation of ‘La Otra Voz’ (1994), by Mexican poet, critic and translator Octavio Paz, a writer to whom he devoted the first years of his carrier as a translator. As Dupont pointed out in some interviews, the struggles in finding a way out to overcome linguistic and cultural obstacles in the process of translating texts from Spanish to Portuguese was paramount for ascertaining his engagement in the long-term project of translating to Brazilian Portuguese the fiction of William Faulkner. His first enterprise was the translation of Faulkner’s trilogy Snopes: The Hamlet (1940) and The Town (1957), the first two novels, were published in 1997 as O povoado and A cidade; in 1999 the last novel, The mansion (1959), was published as A mansão. In 2001, Dupont tackled what is considered one of the most challenging novels by the author due to his use of multiple points of view, As I lay dying (1930). In 2003, The Reivers (1962) was published under the title Os invictos. His enterprise finishes in 2012 with the publication of an anthology of Faulkner’s thriller short-stories Knight’s Gambit (1932) as Lance mortal. Hence, in this paper we will consider the Dupont’s trajectory as a translator, paying special attention to the way in which his identity as such is constituted through the process of translating Faulkner’s works.Keywords: literary translation, translator’s identity, William Faulkner, Wladir DuPont
Procedia PDF Downloads 2501097 Dairy Value Chain: Assessing the Inter Linkage of Dairy Farm and Small-Scale Dairy Processing in Tigray: Case Study of Mekelle City
Authors: Weldeabrha Kiros Kidanemaryam, DepaTesfay Kelali Gidey, Yikaalo Welu Kidanemariam
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Dairy services are considered as sources of income, employment, nutrition and health for smallholder rural and urban farmers. The main objective of this study is to assess the interlinkage of dairy farms and small-scale dairy processing in Mekelle, Tigray. To achieve the stated objective, a descriptive research approach was employed where data was collected from 45 dairy farmers and 40 small-scale processors and analyzed by calculating the mean values and percentages. Findings show that the dairy business in the study area is characterized by a shortage of feed and water for the farm. The dairy farm is dominated by breeds of hybrid type, followed by the so called ‘begait’. Though the farms have access to medication and vaccination for the cattle, they fell short of hygiene practices, reliable shade for the cattle and separate space for the claves. The value chain at the milk production stage is characterized by a low production rate, selling raw milk without adding value and a very meager traditional processing practice. Furthermore, small-scale milk processors are characterized by collecting milk from farmers and producing cheese, butter, ghee and sour milk. They do not engage in modern milk processing like pasteurized milk, yogurt and table butter. Most small-scale milk processors are engaged in traditional production systems. Additionally, the milk consumption and marketing part of the chain is dominated by the informal market (channel), where market problems, lack of skill and technology, shortage of loans and weak policy support are being faced as the main challenges. Based on the findings, recommendations and future research areas are forwarded.Keywords: value-chain, dairy, milk production, milk processing
Procedia PDF Downloads 371096 Examination of Porcine Gastric Biomechanics in the Antrum Region
Authors: Sif J. Friis, Mette Poulsen, Torben Strom Hansen, Peter Herskind, Jens V. Nygaard
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Gastric biomechanics governs a large range of scientific and engineering fields, from gastric health issues to interaction mechanisms between external devices and the tissue. Determination of mechanical properties of the stomach is, thus, crucial, both for understanding gastric pathologies as well as for the development of medical concepts and device designs. Although the field of gastric biomechanics is emerging, advances within medical devices interacting with the gastric tissue could greatly benefit from an increased understanding of tissue anisotropy and heterogeneity. Thus, in this study, uniaxial tensile tests of gastric tissue were executed in order to study biomechanical properties within the same individual as well as across individuals. With biomechanical tests in the strain domain, tissue from the antrum region of six porcine stomachs was tested using eight samples from each stomach (n = 48). The samples were cut so that they followed dominant fiber orientations. Accordingly, from each stomach, four samples were longitudinally oriented, and four samples were circumferentially oriented. A step-wise stress relaxation test with five incremental steps up to 25 % strain with 200 s rest periods for each step was performed, followed by a 25 % strain ramp test with three different strain rates. Theoretical analysis of the data provided stress-strain/time curves as well as 20 material parameters (e.g., stiffness coefficients, dissipative energy densities, and relaxation time coefficients) used for statistical comparisons between samples from the same stomach as well as in between stomachs. Results showed that, for the 20 material parameters, heterogeneity across individuals, when extracting samples from the same area, was in the same order of variation as the samples within the same stomach. For samples from the same stomach, the mean deviation percentage for all 20 parameters was 21 % and 18 % for longitudinal and circumferential orientations, compared to 25 % and 19 %, respectively, for samples across individuals. This observation was also supported by a nonparametric one-way ANOVA analysis, where results showed that the 20 material parameters from each of the six stomachs came from the same distribution with a level of statistical significance of P > 0.05. Direction-dependency was also examined, and it was found that the maximum stress for longitudinal samples was significantly higher than for circumferential samples. However, there were no significant differences in the 20 material parameters, with the exception of the equilibrium stiffness coefficient (P = 0.0039) and two other stiffness coefficients found from the relaxation tests (P = 0.0065, 0.0374). Nor did the stomach tissue show any significant differences between the three strain-rates used in the ramp test. Heterogeneity within the same region has not been examined earlier, yet, the importance of the sampling area has been demonstrated in this study. All material parameters found are essential to understand the passive mechanics of the stomach and may be used for mathematical and computational modeling. Additionally, an extension of the protocol used may be relevant for compiling a comparative study between the human stomach and the pig stomach.Keywords: antrum region, gastric biomechanics, loading-unloading, stress relaxation, uniaxial tensile testing
Procedia PDF Downloads 4331095 The Influence of Travel Experience within Perceived Public Transport Quality
Authors: Armando Cartenì, Ilaria Henke
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The perceived public transport quality is an important driver that influences both customer satisfaction and mobility choices. The competition among transport operators needs to improve the quality of the services and identify which attributes are perceived as relevant by passengers. Among the “traditional” public transport quality attributes there are, for example: travel and waiting time, regularity of the services, and ticket price. By contrast, there are some “non-conventional” attributes that could significantly influence customer satisfaction jointly with the “traditional” ones. Among these, the beauty/aesthetics of the transport terminals (e.g. rail station and bus terminal) is probably one of the most impacting on user perception. Starting from these considerations, the point stressed in this paper was if (and how munch) the travel experience of the overall travel (e.g. how long is the travel, how many transport modes must be used) influences the perception of the public transport quality. The aim of this paper was to investigate the weight of the terminal quality (e.g. aesthetic, comfort and service offered) within the overall travel experience. The case study was the extra-urban Italian bus network. The passengers of the major Italian terminal bus were interviewed and the analysis of the results shows that about the 75% of the travelers, are available to pay up to 30% more for the ticket price for having a high quality terminal. A travel experience effect was observed: the average perceived transport quality varies with the characteristic of the overall trip. The passengers that have a “long trip” (travel time greater than 2 hours) perceived as “low” the overall quality of the trip even if they pass through a high quality terminal. The opposite occurs for the “short trip” passengers. This means that if a traveler passes through a high quality station, the overall perception of that terminal could be significantly reduced if he is tired from a long trip. This result is important and if confirmed through other case studies, will allow to conclude that the “travel experience impact" must be considered as an explicit design variable for public transport services and planning.Keywords: transportation planning, sustainable mobility, decision support system, discrete choice model, design problem
Procedia PDF Downloads 3001094 Development of Map of Gridded Basin Flash Flood Potential Index: GBFFPI Map of QuangNam, QuangNgai, DaNang, Hue Provinces
Authors: Le Xuan Cau
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Flash flood is occurred in short time rainfall interval: from 1 hour to 12 hours in small and medium basins. Flash floods typically have two characteristics: large water flow and big flow velocity. Flash flood is occurred at hill valley site (strip of lowland of terrain) in a catchment with large enough distribution area, steep basin slope, and heavy rainfall. The risk of flash floods is determined through Gridded Basin Flash Flood Potential Index (GBFFPI). Flash Flood Potential Index (FFPI) is determined through terrain slope flash flood index, soil erosion flash flood index, land cover flash floods index, land use flash flood index, rainfall flash flood index. Determining GBFFPI, each cell in a map can be considered as outlet of a water accumulation basin. GBFFPI of the cell is determined as basin average value of FFPI of the corresponding water accumulation basin. Based on GIS, a tool is developed to compute GBFFPI using ArcObjects SDK for .NET. The maps of GBFFPI are built in two types: GBFFPI including rainfall flash flood index (real time flash flood warning) or GBFFPI excluding rainfall flash flood index. GBFFPI Tool can be used to determine a high flash flood potential site in a large region as quick as possible. The GBFFPI is improved from conventional FFPI. The advantage of GBFFPI is that GBFFPI is taking into account the basin response (interaction of cells) and determines more true flash flood site (strip of lowland of terrain) while conventional FFPI is taking into account single cell and does not consider the interaction between cells. The GBFFPI Map of QuangNam, QuangNgai, DaNang, Hue is built and exported to Google Earth. The obtained map proves scientific basis of GBFFPI.Keywords: ArcObjects SDK for NET, basin average value of FFPI, gridded basin flash flood potential index, GBFFPI map
Procedia PDF Downloads 3811093 Corruption, Institutional Quality and Economic Growth in Nigeria
Authors: Ogunlana Olarewaju Fatai, Kelani Fatai Adeshina
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The interplay of corruption and institutional quality determines how effective and efficient an economy progresses. An efficient institutional quality is a key requirement for economic stability. Institutional quality in most cases has been used interchangeably with Governance and these have given room for proxies that legitimized Governance as measures for institutional quality. A poorly-tailored institutional quality has a penalizing effect on corruption and economic growth, while defective institutional quality breeds corruption. Corruption is a hydra-headed phenomenon as it manifests in different forms. The most celebrated definition of corruption is given as “the use or abuse of public office for private benefits or gains”. It also denotes an arrangement between two mutual parties in the determination and allocation of state resources for pecuniary benefits to circumvent state efficiency. This study employed Barro (1990) type augmented model to analyze the nexus among corruption, institutional quality and economic growth in Nigeria using annual time series data, which spanned the period 1996-2019. Within the analytical framework of Johansen Cointegration technique, Error Correction Mechanism (ECM) and Granger Causality tests, findings revealed a long-run relationship between economic growth, corruption and selected measures of institutional quality. The long run results suggested that all the measures of institutional quality except voice & accountability and regulatory quality are positively disposed to economic growth. Moreover, the short-run estimation indicated a reconciliation of the divergent views on corruption which pointed at “sand the wheel” and “grease the wheel” of growth. In addition, regulatory quality and the rule of law indicated a negative influence on economic growth in Nigeria. Government effectiveness and voice & accountability, however, indicated a positive influence on economic growth. The Granger causality test results suggested a one-way causality between GDP and Corruption and also between corruption and institutional quality. Policy implications from this study pointed at checking corruption and streamlining institutional quality framework for better and sustained economic development.Keywords: institutional quality, corruption, economic growth, public policy
Procedia PDF Downloads 1721092 Paper Concrete: A Step towards Sustainability
Authors: Hemanth K. Balaga, Prakash Nanthagopalan
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Every year a huge amount of paper gets discarded of which only a minute fraction is being recycled and the rest gets dumped as landfills. Paper fibres can be recycled only a limited number of times before they become too short or weak to make high quality recycled paper. This eventually adds to the already big figures of waste paper that is being generated and not recycled. It would be advantageous if this prodigious amount of waste can be utilized as a low-cost sustainable construction material and make it as a value added product. The generic term for the material under investigation is paper-concrete. This is a fibrous mix made of Portland cement, water and pulped paper and/or other aggregates. The advantages of this material include light weight, good heat and sound insulation capability and resistance to flame. The disadvantages include low strength compared to conventional concrete and its hydrophilic nature. The properties vary with the variation of cement and paper content in the mix. In the present study, Portland Pozzolona Cement and news print paper were used for the preparation of paper concrete cubes. Initially, investigations were performed to determine the minimum soaking period required for the softening of the paper fibres. Further different methodologies were explored for proper blending of the pulp with cement paste. The properties of paper concrete vary with the variation of cement to paper to water ratio. The study mainly addresses the parameters of strength and weight loss of the concrete cubes with age and the time that is required for the dry paper fibres to become soft enough in water to bond with the cement. The variation of compressive strength with cement content, water content, and time was studied. The water loss of the cubes with time and the minimum time required for the softening of paper fibres were investigated .Results indicate that the material loses 25-50 percent of the initial weight at the end of 28 days, and a maximum 28 day compressive strength (cubes) of 5.4 Mpa was obtained.Keywords: soaking time, difference water, minimum water content, maximum water content
Procedia PDF Downloads 2571091 Exercise Intensity Increasing Appetite, Energy, Intake Energy Expenditure, and Fat Oxidation in Sedentary Overweight Individuals
Authors: Ghalia Shamlan, M. Denise Robertson, Adam Collins
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Appetite control (i.e. control of energy intake) is important for weight maintenance. Exercise contributes to the most variable component of energy expenditure (EE) but its impact is beyond the energy cost of exercise including physiological, behavioural, and appetite effects. Exercise is known to acutely influence effect appetite but evidence as to the independent effect of intensity is lacking. This study investigated the role of exercise intensity on appetite, energy intake (EI), appetite related hormone, fat utilisation and subjective measures of appetite. One hour after a standardised breakfast, 10 sedentary overweight volunteers. Subjects undertook either 8 repeated 60 second bouts of cycling at 95% VO2max (high intensity) or 30 minutes of continuous cycling, at a fixed cadence, equivalent to 50% of the participant’s VO2max (low intensity) in a randomised crossover design. Glucose, NEFA, glucagon-like peptide-1 (GLP-1) were measured fasted, postprandial, and pre and post-exercise. Satiety was assessed subjectively throughout the study using visual analogue scales (VAS). Ad libitum intake of a pasta meal was measured at the end (3-h post-breakfast). Interestingly, there was not significant difference in EE fat oxidation between HI and LI post-exercise. Also, no significant effect of high intensity (HI) was observed on the ad libitum meal, 24h and 48h EI post-exercise. However the mean 24h EI was 3000 KJ lower following HI than low intensity (LI). Despite, no significant differences in hunger score, glucose, NEFA and GLP-1 between both intensities were observed. However, NEFA and GLP-1 plasma level were higher until 30 min post LI. In conclusion, the similarity of EE and oxidation outcomes could give overweight individuals an option to choose between intensities. However, HI could help to reduce EI. There are mechanisms and consequences of exercise in short and long-term appetite control; however, these mechanisms warrant further explanation. These results support the need for future research in to the role of in regulation energy balance, especially for obese people.Keywords: appetite, exercise, food intake, energy expenditure
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