Search results for: diachronic study

Authors: Anilkumar L. Rathod

Abstract:

This paper examines event tourism as a field of study and area of professional practice updating the previous review article published in 2015. In this substantially extended review, a deeper analysis of the field's evolution and development is presented, charting the growth of the literature, focusing both chronologically and thematically. A framework for understanding and creating knowledge about events and tourism is presented, forming the basis which signposts established research themes and concepts and outlines future directions for research. In addition, the review article focuses on constraining and propelling forces, ontological advances, contributions from key journals, and emerging themes and issues. It also presents a roadmap for research activity in event tourism. Published scholarly studies within this period are examined through content analysis, using such keywords as knowledge management, organizational learning, hospitality, tourism, tourist destinations, travel industry, hotels, lodging, motels, hotel industry, gaming, casino hotel and convention to search scholarly research journals. All contributions found are then screened for a hospitality and tourism theme. Researchers mostly discuss knowledge management approach in improving information technology, marketing and strategic planning in order to gain competitive advantage. Overall, knowledge management research is still limited. Planned events in tourism are created for a purpose, and what was once the realm of individual and community initiatives has largely become the realm of professionals and entrepreneurs provides a typology of the four main categories of planned events within an event-tourism context, including the main venues associated with each. It also assesses whether differences exist between socio-demographic groupings. An analysis using primarily descriptive statistics indicated both sub-samples had similar viewpoints although Maharashtra residents tended to have higher scores pertaining to the consequences of gambling. It is suggested that the differences arise due to the greater exposure of Maharashtra residents to the influences of casino development.

Keywords: organizational learning, hospitality, tourism, tourist destinations, travel industry, hotels, lodging, motels, hotel industry, gaming, casino hotel and convention to search scholarly research journals

Procedia PDF Downloads 238

Authors: Xu Feifei

Abstract:

The prevalence of COVID-19 currently is the biggest challenge to improving people's quality of life. Its impact on the health-related quality of life (HRQoL) is highly uncertain and has not been summarized so far. The aim of the present systematic review was to assess and provide an up-to-date analysis of the impact of the COVID-19 pandemic on the HRQoL of participants who have been infected, have not been infected but isolated, frontline, with different diseases, and the general population. Therefore, an electronic search of the literature in PubMed databases was performed from 2019 to July 2022 (without date restriction). PRISMA guideline methodology was employed, and data regarding the HRQoL were extracted from eligible studies. Articles were included if they met the following inclusion criteria: (a) reports on the data collection of the health state utility values (HSUVs) related to COVID-19 from 2019 to 2021; (b) English language and peer-reviewed journals; and (c) original HSUV data; (d) using EQ-5D tool to quantify the HRQoL. To identify studies that reported the effects on COVID-19, data on the proportion of overall HSUVs of participants who had the outcome were collected and analyzed using a one-group meta-analysis. As a result, thirty-two studies fulfilled the inclusion criteria and, therefore, were included in the systematic review. A total of 45295 participants and provided 219 means of HSUVs during COVID-19 were included in this systematic review. The range of utility is from 0.224 to 1. The study included participants from Europe (n=16), North America (n=4), Asia (n=10), South America (n=1), and Africa (n=1). Twelve articles showed that the HRQoL of the participants who have been infected with COVID-19 (range of overall HSUVs from 0.6125 to 0.863). Two studies reported the population of frontline workers (the range of overall HSUVs from 0.82 to 0.93). Seven of the articles researched the participants who had not been infected with COVID-19 but suffered from morbidities during the pandemic (range of overall HSUVs from 0.5 to 0.96). Thirteen studies showed that the HRQoL of the respondents who have not been infected with COVID-19 and without any morbidities (range of overall HSUVs from 0.64 to 0.964). Moreover, eighteen articles reported the outcomes of overall HSUVs during the COVID-19 pandemic in different population groups. The estimate of overall HSUVs of direct COVID-19 experience population (n=1333) was 0.751 (95% CI 0.670 - 0.832, I2 = 98.64%); the estimate of frontline population (n=610) was 0.906 ((95% CI 0.854 – 0.957, I2 = 98.61%); participants with different disease (n=132) were 0.768 (95% CI 0.515 - 1.021, I2= 99.26%); general population without infection history (n=29,892) was 0.825 (95% CI 0.766 - 0.885, I2 =99.69%). Conclusively, taking into account these results, this systematic review might confirm that COVID-19 has a negative impact on the HRQoL of the infected population and illness population. It provides practical value for cost-effectiveness model analysis of health states related to COVID-19.

Keywords: COVID-19, health-related quality of life, meta-analysis, systematic review, utility value

Procedia PDF Downloads 82

Authors: Suraj D. Khadka, Priyantha W. Jayawickrama

Abstract:

In search of a sustainable construction material, geopolymer has been investigated for past decades to evaluate its advantage over conventional products. Synthesis of geopolymer requires a source of aluminosilicate mixed with sodium hydroxide and sodium silicate at different proportions to maintain a Si/Al molar ratio of 1-3 and Na/Al molar ratio of unity. A comprehensive geopolymer study was performed with Metakaolin and Class C Fly ash as primary aluminosilicate sources. Synthesized geopolymer was analyzed for time-dependent viscosity, setting period and strength at varying initial moisture content, curing temperature and humidity. Different concentration of Ca(OH)₂ and CaSO₄.2H₂O were added to vary the amount of calcium contained in synthesized geopolymer. Influence of calcium content in unconfined compressive strength behavior of geopolymer were analyzed. Finally, Scanning Electron Microscopy-Energy Dispersive Spectroscopy (SEM-EDS) was performed to investigate the hardened product. It was observed that fly ash based geopolymer had shortened setting time and faster increase in viscosity as compared to geopolymer synthesized from metakaolin. This was primarily attributed to higher calcium content resulting in formation of calcium silicate hydrates (CSH). SEM-EDS was performed to verify the presence of CSH phases. Spectral analysis of geopolymer prepared by addition of Ca(OH)₂ and CaSO₄.2H₂O indicated higher CSH phases at higher concentration. It was observed that lower concentration of added calcium favored strength gain in geopolymer. However, at higher calcium concentration, decrease in strength was observed. Strength variation was also observed with humidity at initial curing condition. At 100% humidity, geopolymer with added calcium presented higher strength compared to samples cured at ambient humidity condition (40%). Reduction in strength in these samples at lower humidity was primarily attributed to reduction in moisture content in specimen due to the formation of CSH phases and loss of moisture through evaporation. For low calcium content geopolymers, with increase in temperature, gain in strength was observed with maximum strength observed at 200 ˚C. However, samples with higher calcium content demonstrated severe cracking resulting in low strength at elevated temperatures.

Keywords: calcium silicate hydrates, geopolymer, humidity, Scanning Electron Microscopy-Energy Dispersive Spectroscopy, unconfined compressive strength

Procedia PDF Downloads 127

Authors: Krytskyy T.

Abstract:

Introduction: The role of androgen deficiency in men as a factor in the pathogenesis of many somatic diseases is unmistakable. The interaction of thyroid and sex hormones with hypothyroidism in men is still the subject of discussions. The purpose of the study is to assess the androgen status of men with primary hypothyroidism, depending on its duration and the state of compensation. Materials and methods: 45 men with primary hypothyroidism aged 35 to 60 years, as well as 25 healthy men, who formed a control group, were under supervision. A selection of men for examination was conducted in the process of outpatient and in-patient treatment at the endocrinology department of the University Hospital in Ternopil. The functional state of the pituitary-gonadal system was evaluated in order to characterize the androgen status of patients. The concentration of follicle stimulating hormone, luteinizing hormone, prolactin, thyroid-stimulating hormone was determined in blood with the help of enzyme-linked method. Also, the content of hormones: total testosterone, linking sex hormones globulin were determined. Results: Reduced total testosterone (TT) content was found in 42.2% of patients with hypothyroidism. Herewith in 17.8% of patients, blood TT levels were lower than 8.0 nmol / L, and in 11 (24.4%) men, the rate was in the range of 8.0 to 12.0 nmol / L. Based on the results of the determination of the content of free testosterone (FT), the frequency of laboratory hypogonadism in men with hypothyroidism was higher than the results of the determination of TT. The degree of compensation of hypothyroidism probably did not affect the average levels of gonadotropic and sex hormones. Conclusions: Reduced total testosterone content was found in 42.2% of patients with primary hypothyroidism. Herewith, in 17.8% of patients blood TT levels were lower than 8.0 nmol / L, which is a sign of absolute deficiency of testosterone, and in 24.4% of men the rate ranged from 8.0 to 12.0 nmol / l , indicating partial androgen deficiency. Linking sex hormones globulin levels were believed to be lower in 46.7% of patients with hypothyroidism compared to control group. The average levels of E2 in the examined patients did not significantly differ from the mean of control group. FSH, LH, and prolactin levels in men with hypothyroidism were within the normal age limits and probably did not differ from those of control group. The degree of compensation of hypothyroidism probably did not affect the average levels of gonadotropic and sex hormones. The mean LH content in the blood was significantly increased in men with a duration of hypothyroidism up to 5 years and did not differ from that of the control group and in men with a duration of hypothyroidism over 5 years. In men with hypothyroidism, a probable reduction in T / LH coefficient is found. The obtained data may indicate a combined lesion of the central and peripheral parts of the pituitary-gonadal system in men with hypothyroidism.

Keywords: androgenic status, hypothyroidism, testosterone, linking sex hormones globulin

Procedia PDF Downloads 196

Authors: Hsiu-Tsu Cho

Abstract:

Collective efficacy refers to a group’s sense of its capacity to complete a task successfully or to reach objectives. Little effort has been expended on investigating the relationship between the emotion expression of a leader and collective efficacy. In this study, we examined the impact of the different emotions and emotion expression of a group leader on collective efficacy and explored whether the emotion–expressive effects differed under conditions of negative and positive emotions. A total of 240 undergraduate and graduate students recruited using Facebook and posters at a university participated in this research. The participants were separated randomly into 80 groups of four persons consisting of three participants and a confederate. They were randomly assigned to one of five conditions in a 2 (pride vs. guilt) × 2 (emotion expression of group leader vs. no emotion expression of group leader) factorial design and a control condition. Each four-person group was instructed to get the reward in a group competition of solving the five-disk Tower of Hanoi puzzle and making decisions on an investment case. We surveyed the participants by employing the emotional measure revised from previous researchers and collective efficacy questionnaire on a 5-point scale. To induce an emotion of pride (or guilt), the experimenter announced whether the group performance was good enough to have a chance of getting the reward (ranking the top or bottom 20% among all groups) after group task. The leader (confederate) could either express or not express a feeling of pride (or guilt) following the instruction according to the assigned condition. To check manipulation of emotion, we added a control condition under which the experimenter revealed no results regarding group performance in maintaining a neutral emotion. One-way ANOVAs and post hoc pairwise comparisons among the three emotion conditions (pride, guilt, and control condition) involved assigning pride and guilt scores (pride: F(1,75) = 32.41, p < .001; guilt: F(1,75) = 6.75, p < .05). The results indicated that manipulations of emotion were successful. A two-way between-measures ANOVA was conducted to examine the predictions of the main effects of emotion types and emotion expression as well as the interaction effect of these two variables on collective efficacy. The experimental findings suggest that pride did not affect collective efficacy (F(1,60) = 1.90, ns.) more than guilt did and that the group leader did not motivate collective efficacy regardless of whether he or she expressed emotion (F(1,60) = .89, ns.). However, the interaction effect of emotion types and emotion expression was statistically significant (F(1,60) = 4.27, p < .05, ω2 = .066); the effects accounted for 6.6% of the variance. Additional results revealed that, under the pride condition, the leader enhanced group efficacy when expressing emotion, whereas, under the guilt condition, an expression of emotion could reduce collective efficacy. Overall, these findings challenge the assumption that the effect of expression emotion are the same on all emotions and suggest that a leader should be cautious when expressing negative emotions toward a group to avoid reducing group effectiveness.

Keywords: collective efficacy, group leader, emotion expression, pride, guilty

Procedia PDF Downloads 330

Authors: Rima Mammadova

Abstract:

Azerbaijan is a developing country that tries to keep its own culture and traditions. At the same time tries to get benefit from the experience and knowledge of the developed countries. After the collapse of the Soviet Union, Azerbaijan got its independence and currently, implements various programs and policy initiatives to the development of different fields, such as an education, human rights, etc. Disability related issues are also in the main priority list of the country. During the Soviet Union, children with disabilities studied in the special schools, which called boarding schools. They were isolated from the society and most of them were not able to get their higher education. As the result of this kind of tendency, they were in dependence on their parents, relatives and especially the government, as there were several kind of pensions provided by the government depending on the level of disability. Although Azerbaijan maintain different programs, the remnants of the Soviet period still exists. This paper investigates the current situation in Azerbaijan concerning the higher education of people with disabilities. Qualitative and quantitative research methods used in this paper. As a qualitative method a literature review was done on what the term “disability” is and what kind of education rights possess people with disabilities in Azerbaijan. A detailed research also was done on legislation of the Republic of Azerbaijan concerning the education rights of people with disabilities in Azerbaijan. As a quantitative method, questionnaire was used. The questionnaires were sent to the 8 Azerbaijani Higher Education Institutions (HEIs) which are located in different regions of Azerbaijan in order to assess and evaluate the situation concerning the students with disabilities. The main aims of these questionnaires were to find out how many students with disabilities study in Higher Education Institutions in 8 HEIs and what kind of obstacles and challenges Institutions face concerning the education of students with disabilities. The researches provided for the project brought up the results that people with disabilities possess all rights concerning the education rights legally. However in the practice they face various types of obstacles and challenges. The number of students with disabilities in HEIs in Azerbaijan is significantly low. There are several kind of reasons that affect the number of students with disabilities in HEIs. As was mentioned before the remnants of the Soviet period exists in Azerbaijan and children with disabilities get their education in boarding schools and in most cases, these boarding schools give education till the 9th class, but to enter the University, pupils have to finish 11 classes in Azerbaijan. As a result, pupils with disabilities automatically disqualify to enter the university. The paper comes into conclusion that to eliminate the isolation of pupils with disabilities from HEIs, the government should pay more attention to the special schools for the pupils with disabilities, the boarding schools should be cancelled and etc. By the applying these kind of changes the rights of people with disabilities will be provided not only theoretically but also practically.

Keywords: Azerbaijan, disability, students with disabilities, boarding schools

Procedia PDF Downloads 267

Authors: Sharat Chandra, Zilong Wang, Ru-Rong Ji, Andrey Bortsov

Abstract:

Chronic pain (CP) therapeutic approaches have limited efficacy. As a result, doctors are prescribing opioids for chronic pain, leading to opioid overuse, abuse, and addiction epidemic. Therefore, the development of effective and safe CP drugs remains an unmet medical need. Voltage-gated sodium (Nav) channels act as cardiovascular and neurological disorder’s molecular targets. Nav channels selective inhibitors are hard to design because there are nine closely-related isoforms (Nav1.1-1.9) that share the protein sequence segments. We are targeting the Nav1.7 found in the peripheral nervous system and engaged in the perception of pain. The objective of this project was to screen a 1.5 million compound library for identification of inhibitors for Nav1.7 with analgesic effect. In this study, we designed a protocol for identification of isoform-selective inhibitors of Nav1.7, by utilizing the prior information on isoform-selective antagonists. First, a similarity search was performed; then the identified hits were docked into a binding site on the fourth voltage-sensor domain (VSD4) of Nav1.7. We used the FTrees tool for similarity searching and library generation; the generated library was docked in the VSD4 domain binding site using FlexX and compounds were shortlisted using a FlexX score and SeeSAR hyde scoring. Finally, the top 25 compounds were tested with molecular dynamics simulation (MDS). We reduced our list to 9 compounds based on the MDS root mean square deviation plot and obtained them from a vendor for in vitro and in vivo validation. Whole-cell patch-clamp recordings in HEK-293 cells and dorsal root ganglion neurons were conducted. We used patch pipettes to record transient Na⁺ currents. One of the compounds reduced the peak sodium currents in Nav1.7-HEK-293 stable cell line in a dose-dependent manner, with IC50 values at 0.74 µM. In summary, our computer-aided analgesic discovery approach allowed us to develop pre-clinical analgesic candidate with significant reduction of time and cost.

Keywords: chronic pain, voltage-gated sodium channel, isoform-selective antagonist, similarity search, virtual screening, analgesics development

Procedia PDF Downloads 124

Authors: Mahdi Nasiri Tabrizi, A. Dadkhah, M. Khirkhah

Abstract:

In order to study the effect of planting on yield, yield components and quality traits in bread and durum wheat varieties, a field split-plot experiment based on complete randomized design with three replications was conducted in Agricultural and Natural Resources Research Center of Razavi Khorasan located in city of Mashhad during 2013-2014. Main factor were consisted of five sowing dates (first October, fifteenth December, first March, tenth March, twentieth March) and as sub-factors consisted of different bread wheat (Bahar, Pishgam, Pishtaz, Mihan, Falat and Karim) and two durum wheat (Dena and Dehdasht). According to results of analysis variance the effect of planting date was significant on all examined traits (grain yield, biological yield, harvest index, number of grain per spike, thousands kernel weight, number of spike per square meter, plant height, the number of days to heading, the number of days to maturity, during the grain filling period, percentage of wet gluten, percentage of dry gluten, gluten index, percentage of protein). By delay in planting, majority of traits significantly decreased, except quality traits (percentage of wet gluten, percentage of dry gluten and percentage of protein). Results of means comparison showed, among planting date the highest grain yield and biological yield were related to first planting date (Octobr) with mean of production of 5/6 and 1/17 tons per hectare respectively and the highest bread quality (gluten index) with mean of 85 and percentage of protein with mean of 13% to fifth planting date also the effect of genotype was significant on all traits. The highest grain yield among of studied wheat genotypes was related to Dehdasht cultivar with an average production of 4.4 tons per hectare. The highest protein percentage and bread quality (gluten index) were related to Dehdasht cultivar with 13.4% and Falat cultivar with number of 90 respectively. The interaction between cultivar and planting date was significant on all traits and different varieties had different trend for these traits. The highest grain yield was related to first planting date (October) and Falat cultivar with an average of production of 6/7 tons per hectare while in grain yield did not show a significant different with Pishtas and Mihan cultivars also the most of gluten index (bread quality index) and protein percentage was belonged to the third planting date and Karim cultivar with 7.98 and Dena cultivar with 7.14% respectively.

Keywords: yield component, yield, planting date, cultivar, quality traits, wheat

Procedia PDF Downloads 430

Authors: Housein Deli, Loui Al-Shrouf, Hammoud Al Joumaa, Mohieddine Jelali

Abstract:

When forming metallic materials, fluctuations in material properties, process conditions, and wear lead to deviations in the component geometry. Several hundred features sometimes need to be measured, especially in the case of functional and safety-relevant components. These can only be measured offline due to the large number of features and the accuracy requirements. The risk of producing components outside the tolerances is minimized but not eliminated by the statistical evaluation of process capability and control measurements. The inspection intervals are based on the acceptable risk and are at the expense of productivity but remain reactive and, in some cases, considerably delayed. Due to the considerable progress made in the field of condition monitoring and measurement technology, permanently installed sensor systems in combination with machine learning and artificial intelligence, in particular, offer the potential to independently derive forecasts for component geometry and thus eliminate the risk of defective products - actively and preventively. The reliability of forecasts depends on the quality, completeness, and timeliness of the data. Measuring all geometric characteristics is neither sensible nor technically possible. This paper, therefore, uses the example of car seat rail production to discuss the necessary first step of feature selection and reduction by correlation analysis, as otherwise, it would not be possible to forecast components in real-time and inline. Four different car seat rails with an average of 130 features were selected and measured using a coordinate measuring machine (CMM). The run of such measuring programs alone takes up to 20 minutes. In practice, this results in the risk of faulty production of at least 2000 components that have to be sorted or scrapped if the measurement results are negative. Over a period of 2 months, all measurement data (> 200 measurements/ variant) was collected and evaluated using correlation analysis. As part of this study, the number of characteristics to be measured for all 6 car seat rail variants was reduced by over 80%. Specifically, direct correlations for almost 100 characteristics were proven for an average of 125 characteristics for 4 different products. A further 10 features correlate via indirect relationships so that the number of features required for a prediction could be reduced to less than 20. A correlation factor >0.8 was assumed for all correlations.

Keywords: long-term SHM, condition monitoring, machine learning, correlation analysis, component prediction, wear prediction, regressions analysis

Procedia PDF Downloads 50

Authors: Abejide Dorcas Ropo, Falusi Olamide Ahmed, Daudu Oladipupo Abdulazeez Yusuf, Muhammad Liman Muhammad, Gado Aishatu Adamu

Abstract:

Bambara groundnut is an indigenous African legume with great potential to tackle the problem of food insecurity in Nigeria. A germplasm collection mission was carried out in collaboration with the Agricultural Developments Project (ADP) Extension officers of Nigeria between October and December 2014. Bambara groundnut seeds were collected from farmers in different States in Nigeria, such as Kaduna, Niger, Kogi, Benue, Plateau, Adamawa, Nasarawa, Jigawa, Enugu, and Federal Capital Territoy (FCT) Abuja. Some seeds were also collected from National Centre for Genetic Resources and Biotechnology (NACGRAB). The seeds were phenotyped using the descriptor list of Vigna subterranea produced by the International Plant Genetic Resource Institute. A total of 45 original seed lots were collected, which comprised of mixed seeds having different seed coat colours (15) and pure seeded accessions having the same seed coat and eye colour (30). After sorting, a total of 83 accessions were derived from the 45 original seed lots collected, and a total of 24 distinct seed morphotypes with varying seed coat colours and eye colours were identified from the collections. They include cream ( cream ash eye, cream plain eye, and cream black eye), cream purplish spots, cream brown spots/stripe, cream black stripe, cream dark brown patches, cream light grey spots, cream black patches, black, red, light red, dark red, brownish red, brown speckled with black, red speckled with black, brown, brown with brown pattern below hilum, brown with black pattern below hilum, cream black, grey brown, grey black and variegated red. The highest number of accessions were collected from NACGRAB (11), followed by Niger State (10), and the lowest from Benue, Jigawa, and Adamawa States (2). Niger State also had the highest number of mixed seeds. The different seed phenotypes observed in the study are important for the field production of true-to-type lines and can be exploited for the genetic improvement of the Bambara groundnut.

Keywords: Bambara groundnut, characterization, collection, germplasm, phenotypic

Procedia PDF Downloads 142

Authors: Emil Iskandarov, Nazrin Agayeva

Abstract:

Background: The effectiveness of hormone suppressive therapy (HST) in patients with nodular goiter (NG) is controversial. The aim of this study was to identify the impact of long-time HST on the Quality of Life (QoL) of patients with NG. Material and Methods: A retrospective analysis of 146 patients with NG showed treated with HST showed that in 38,4% of cases, HST was not effective. Nodules were increased in size and moreover, and new nodules were developed. Statistical procedure identified the predictors of resistant nodules: only one nodule in the left lobe; nodule size >17mm; calcinate within the nodule. 174 patients with NG, by whom predictors of resistant nodules were established, were informed about the results of previous research and surgery was suggested. Eighty-eight patients (the basic group) agreed with surgery and thyroidectomy was led. 86 patients (control group) ignored the suggestion and wished to receive HST. 3, 6 and 12 months after starting HST; control group patients were examined. HST was non-effective and patients, due to developing symptoms, were operated on. Patients in both groups were followed up 3, 6 and 12 months after thyroidectomy. Quality of Life was checked with the SF-36 survey form and compared between groups. The statistical analysis was performed with the non-parametric Mann–Whitney U test and with the Student t-test. P values ＜0.05 were considered statistically significant. Results and Discussions: QoL of patients in the basic and control groups 3 months after surgery was almost the same. However, Emotional problems severely interfered with patients in a control group with normal social activities with family, friends, and neighbors. The causes were related to the non-effective HST treatment before surgery: stress for forgetting to take drugs timely every day for a long time; blood tests for thyroid hormone level; needle biopsies of nodules for cancer screening and regular ultrasound investigations, which showed that nodules not diminished in size. Changing the treatment method after 1-year non-effective HST and delayed surgery negatively impacted patient's QoL. Social role functioning and mental health in the control group were also impaired and the difference between the results in the basic group was statistically significant (p <0.05). Conclusion: Predictors, such as only one nodule, the width of nodules more than 17mm, and the existence of calcinate within the nodule, are able to forecast the resistant nodules. HST in patients with resistant nodules is non-effective and surgery is suggested in patients with resistant nodules in the thyroid gland. Long time HST has a negative impact on the QoL patient after surgery.

Keywords: thyroid gland, nodule, hormone suppressive therapy, quality of life

Procedia PDF Downloads 129

Authors: Cagri Mollamahmutoglu, Aykut Levent, Ali Mercan

Abstract:

Micro-beams are one of the most common components of Nano-Electromechanical Systems (NEMS) and Micro Electromechanical Systems (MEMS). For this reason, static bending, buckling, and free vibration analysis of micro-beams have been the subject of many studies. In addition, micro-beams restrained with elastic type foundations have been of particular interest. In the analysis of microstructures, closed-form solutions are proposed when available, but most of the time solutions are based on numerical methods due to the complex nature of the resulting differential equations. Thus, a robust and efficient solution method has great importance. In this study, a mixed finite element formulation is obtained for a functionally graded Timoshenko micro-beam resting on two-parameter elastic foundation. In the formulation modified couple stress theory is utilized for the micro-scale effects. The equation of motion and boundary conditions are derived according to Hamilton’s principle. A functional, derived through a scientific procedure based on Gateaux Differential, is proposed for the bending and buckling analysis which is equivalent to the governing equations and boundary conditions. Most important advantage of the formulation is that the mixed finite element formulation allows usage of C₀ type continuous shape functions. Thus shear-locking is avoided in a built-in manner. Also, element matrices are sparsely populated and can be easily calculated with closed-form integration. In this framework results concerning the effects of micro-scale length parameter, power-law parameter, aspect ratio and coefficients of partially or fully continuous elastic foundation over the static bending, buckling, and free vibration response of FG-micro-beam under various boundary conditions are presented and compared with existing literature. Performance characteristics of the presented formulation were evaluated concerning other numerical methods such as generalized differential quadrature method (GDQM). It is found that with less computational burden similar convergence characteristics were obtained. Moreover, formulation also includes a direct calculation of the micro-scale related contributions to the structural response as well.

Keywords: micro-beam, functionally graded materials, two-paramater elastic foundation, mixed finite element method

Procedia PDF Downloads 162

Authors: Ayat-Allah Bouramdane

Abstract:

Power generation from offshore wind energy does not emit carbon dioxide or other air pollutants and therefore play a role in reducing greenhouse gas emissions from the energy sector. In addition, these systems are considered more efficient than onshore wind farms, as they generate electricity from the wind blowing across the sea, thanks to the higher wind speed and greater consistency in direction due to the lack of physical interference that the land or human-made objects can present. This means offshore installations require fewer turbines to produce the same amount of energy as onshore wind farms. However, offshore wind farms require more complex infrastructure to support them and, as a result, are more expensive to construct. In addition, higher wind speeds, strong seas, and accessibility issues makes offshore wind farms more challenging to maintain. This study uses a combination of Geographic Referenced Information (GRI) and Analytic Hierarchy Process (AHP) to identify the most suitable sites for offshore wind farm development in Morocco, with a particular focus on the Dakhla city. A range of environmental, socio-economic, and technical criteria are taken into account to solve this complex Multi-Criteria Decision-Making (MCDM) problem. Based on experts' knowledge, a pairwise comparison matrix at each level of the hierarchy is performed, and fourteen sub-criteria belong to the main criteria have been weighted to generate the site suitability of offshore wind plants and obtain an in-depth knowledge on unsuitable areas, and areas with low-, moderate-, high- and very high suitability. We find that wind speed is the most decisive criteria in offshore wind farm development, followed by bathymetry, while proximity to facilities, the sediment thickness, and the remaining parameters show much lower weightings rendering technical parameters most decisive in offshore wind farm development projects. We also discuss the potential of other marine renewable energy potential, in Morocco, such as wave and tidal energy. The proposed approach and analysis can help decision-makers and can be applied to other countries in order to support the site selection process of offshore wind farms.

Keywords: analytic hierarchy process, dakhla, geographic referenced information, morocco, multi-criteria decision-making, offshore wind, site suitability

Procedia PDF Downloads 157

Authors: E. K. K. Agyeman, P. Mousseau, A. Sarda, D. Edelin

Abstract:

During the cooling of hot metals by the circulation of water in canals formed by boring holes in the metal, the rapid phase change of the water due to the high initial temperature of the metal leads to a non homogenous distribution of the phases within the canals. The liquid phase dominates towards the entrance of the canal while the gaseous phase dominates towards the exit. As a result of the different thermal properties of both phases, the metal is not uniformly cooled. This poses a problem during the cooling of moulds, where a uniform temperature distribution is needed in order to ensure the integrity of the part being formed. In this study, the simultaneous use of multiple water jets and an airflow for the uniform and controlled cooling of a steel block is investigated. A circular hole is bored at the centre of the steel block along its length and a perforated steel pipe is inserted along the central axis of the hole. Water jets that impact the internal surface of the steel block are generated from the perforations in the steel pipe when the water within it is put under pressure. These jets are oriented in the opposite direction to that of gravity. An intermittent airflow is imposed in the annular space between the steel pipe and the surface of hole bored in the steel block. The evolution of the temperature with respect to time of the external surface of the block is measured with the help of thermocouples and an infrared camera. Due to the high initial temperature of the steel block (350 °C), the water changes phase when it impacts the internal surface of the block. This leads to high heat fluxes. The strategy used to control the cooling speed of the block is the intermittent impingement of its internal surface by the jets. The intervals of impingement and of non impingement are varied in order to achieve the desired result. An airflow is used during the non impingement periods as an additional regulator of the cooling speed and to improve the temperature homogeneity of the impinged surface. After testing different jet positions, jet speeds and impingement intervals, it’s observed that the external surface of the steel block has a uniform temperature distribution along its length. However, the temperature distribution along its width isn’t uniform with the maximum temperature difference being between the centre of the block and its edge. Changing the positions of the jets has no significant effect on the temperature distribution on the external surface of the steel block. It’s also observed that reducing the jet impingement interval and increasing the non impingement interval slows down the cooling of the block and improves upon the temperature homogeneity of its external surface while increasing the duration of jet impingement speeds up the cooling process.

Keywords: cooling speed, homogenous cooling, jet impingement, phase change

Procedia PDF Downloads 125

Authors: Bryan Clark B. Hernandez, Eugene C. Herrera, Kazuo Nadaoka

Abstract:

Mangrove forests thriving in intertidal zones in tropical and subtropical regions of the world offer a range of ecosystem services including carbon storage and sequestration. They can regulate the detrimental effects of climate change due to carbon releases two to four times greater than that of mature tropical rainforests. Moreover, they are effective natural defenses against storm surges and tsunamis. However, their proliferation depends significantly on the prevailing hydroperiod at the coast. In the Philippines, these coastal ecosystems have been severely threatened with a 50% decline in areal extent observed from 1918 to 2010. The highest decline occurred in 1950 - 1972 when national policies encouraged the development of fisheries and aquaculture. With the intensive land use conversion upstream, changes in the freshwater-saltwater envelope at the coast may considerably impact mangrove growth conditions. This study investigates a developing urban watershed in Kalibo, Aklan province with a 220-hectare mangrove forest replanted for over 30 years from coastal mudflats. Since then, the mangrove forest was sustainably conserved and declared as protected areas. Hybrid land cover classification technique was used to classify Landsat images for years, 1990, 2010, and 2017. Digital elevation model utilized was Interferometric Synthetic Aperture Radar (IFSAR) with a 5-meter resolution to delineate the watersheds. Using numerical modelling techniques, the hydrologic and hydraulic analysis of the influence of land cover change to flow and sediment dynamics was simulated. While significant land cover change occurred upland, thereby increasing runoff and sediment loads, the mangrove forests abundance adjacent to the coasts for the urban watershed, was somehow sustained. However, significant alteration of the coastline was observed in Kalibo through the years, probably due to the massive land-use conversion upstream and significant replanting of mangroves downstream. Understanding the hydrologic-hydraulic response of these watersheds to change land cover is essential to helping local government and stakeholders facilitate better management of these mangrove ecosystems.

Keywords: coastal mangroves, hydrologic model, land cover change, Philippines

Procedia PDF Downloads 123

Authors: Rose Vanessa Bandeira Reidel, Bernardo Melai, Pier Luigi Cioni, Luisa Pistelli

Abstract:

Ziziphus jujuba Miller is a common species of the Ziziphus genus (Rhamnaceae family) native to the tropics and subtropics known for its edible fruits, fresh consumed or used in healthy food, as flavoring and sweetener. Many phytochemicals and biological activities are described for this species. In this work, the aroma profiles emitted in vivo by whole fresh organs (leaf, bud flower, flower, green and red fruits) were analyzed separately by mean of solid phase micro-extraction (SPME) coupled with gas chromatography mass spectrometry (GC-MS). The emitted volatiles from different plant parts were analysed using Supelco SPME device coated with polydimethylsiloxane (PDMS, 100µm). Fresh plant material was introduced separately into a glass conical flask and allowed to equilibrate for 20 min. After the equilibration time, the fibre was exposed to the headspace for 15 min at room temperature, the fibre was re-inserted into the needle and transferred to the injector of the CG and CG-MS system, where the fibre was desorbed. All the data were submitted to multivariate statistical analysis, evidencing many differences amongst the selected plant parts and their developmental stages. A total of 144 compounds were identified corresponding to 94.6-99.4% of the whole aroma profile of jujube samples. Sesquiterpene hydrocarbons were the main chemical class of compounds in leaves also present in similar percentage in flowers and bud flowers where (E, E)-α-farnesene was the main constituent in all cited plant parts. This behavior can be due to a protection mechanism against pathogens and herbivores as well as resistance to abiotic factors. The aroma of green fruits was characterized by high amount of perillene while the red fruits release a volatile blend mainly constituted by different monoterpenes. The terpenoid emission of flesh fruits has important function in the interaction with animals including attraction of seed dispersers and it is related to a good quality of fruits. This study provides for the first time the chemical composition of the volatile emission from different Ziziphus jujuba organs. The SPME analyses of the collected samples showed different patterns of emission and can contribute to understand their ecological interactions and fruit production management.

Keywords: Rhamnaceae, aroma profile, jujube organs, HS-SPME, GC-MS

Procedia PDF Downloads 256

Authors: Mariya V. Yanyukina, Michael A. Bolotov

Abstract:

Assembling accuracy is the degree of accordance between the actual values of the parameters obtained during assembly, and the values specified in the assembly drawings and technical specifications. However, the assembling accuracy depends not only on the quality of the production process but also on the correctness of the assembly process. Therefore, preliminary calculations of assembly stages are carried out to verify the correspondence of real geometric parameters to their acceptable values. In the aviation industry, most calculations involve interacting dimensional chains. This greatly complicates the task. Solving such problems requires a special approach. The purpose of this article is to carry out the problem of improving the technology of assembly of aviation units by use of computer calculations. One of the actual examples of the assembly unit, in which there is an interacting dimensional chain, is the turbine wheel of gas turbine engine. Dimensional chain of turbine wheel is formed by geometric parameters of disk and set of blades. The interaction of the dimensional chain consists in the formation of two chains. The first chain is formed by the dimensions that determine the location of the grooves for the installation of the blades, and the dimensions of the blade roots. The second dimensional chain is formed by the dimensions of the airfoil shroud platform. The interaction of the dimensional chain of the turbine wheel is the interdependence of the first and second chains by means of power circuits formed by a plurality of middle parts of the turbine blades. The timeliness of the calculation of the dimensional chain of the turbine wheel is the need to improve the technology of assembly of this unit. The task at hand contains geometric and mathematical components; therefore, its solution can be implemented following the algorithm: 1) research and analysis of production errors by geometric parameters; 2) development of a parametric model in the CAD system; 3) creation of set of CAD-models of details taking into account actual or generalized distributions of errors of geometrical parameters; 4) calculation model in the CAE-system, loading of various combinations of models of parts; 5) the accumulation of statistics and analysis. The main task is to pre-simulate the assembly process by calculating the interacting dimensional chains. The article describes the approach to the solution from the point of view of mathematical statistics, implemented in the software package Matlab. Within the framework of the study, there are data on the measurement of the components of the turbine wheel-blades and disks, as a result of which it is expected that the assembly process of the unit will be optimized by solving dimensional chains.

Keywords: accuracy, assembly, interacting dimension chains, turbine

Procedia PDF Downloads 373

Authors: Dina Magnaye

Abstract:

In the Philippines, the performance of the agricultural sector is gauged through crop productivity and returns from farm production rather than the biodiversity in the agricultural ecosystem. Agricultural development hinges on the overall goal of increasing productivity through intensive agriculture, monoculture system, utilization of high yielding varieties in plants, and genetic upgrading in animals. This merits an analysis of the role of agro-biodiversity in terms of increasing productivity, food security and economic returns from community-based pro-biodiversity enterprises. These enterprises conserve biodiversity while equitably sharing production income in the utilization of biological resources. The study aims to determine how community-based pro-biodiversity enterprises become instrumental in local climate change adaptation and agro-biodiversity conservation as input to local green economic development planning. It also involves an assessment of the role of agrobiodiversity in terms of increasing productivity, food security and economic returns from community-based pro-biodiversity enterprises. The perceptions of the local community members both in urban and upland rural areas on community-based pro-biodiversity enterprises were evaluated. These served as a basis in developing a planning modality that can be mainstreamed in the management of local green economic enterprises to benefit the environment, provide local income opportunities, conserve species diversity, and sustain environment-friendly farming systems and practices. The interviews conducted with organic farmer-owners, entrepreneur-organic farmers, and organic farm workers revealed that pro-biodiversity enterprise such as organic farming involved the cyclic use of natural resources within the carrying capacity of a farm; recognition of the value of tradition and culture especially in the upland rural area; enhancement of socio-economic capacity; conservation of ecosystems in harmony with nature; and climate change mitigation. The suggested planning modality for community-based pro-biodiversity enterprises for a green economy encompasses four (4) phases to include community resource or capital asset profiling; stakeholder vision development; strategy formulation for sustained enterprises; and monitoring and evaluation.

Keywords: agro-biodiversity, agro-biodiversity conservation, local green economy, organic farming, pro-biodiversity enterprise

Procedia PDF Downloads 362

Authors: Karla Lebedoff, Susan Walsh, Michelle Bain

Abstract:

Eczema is a chronic atopy condition requiring long-term daily management in children. Written action plans for other chronic atopic conditions, such as asthma and food allergies, are widely recommended and distributed to pediatric patients' parents and caregivers, seeking to improve clinical outcomes and become empowered to manage the patient's ever-changing symptoms. Written action plans for eczema, referred to as "asthma of the skin," are not routinely used in practice. Parents of children suffering from eczema rarely receive a written action plan to follow, and commendations supporting eczema action plans are inconsistent. Pediatric patients between birth and 18 years old who were followed for eczema at an urban Midwest community hospital were eligible to participate in this quality improvement project. At the initial visit, parents received instructions on individualized eczema action plans for their child and completed two validated surveys: Health Confidence Score (HCS) and Patient-Oriented Eczema Measure (POEM). Pre- and post-survey responses were collected, and clinical symptom presentation at follow-up were outcome determinants. Project implementation was guided by Institute for Healthcare Improvement's Step-up Framework and the Plan-Do-Study-Act cycle. This project measured clinical outcomes and parent confidence in self-management of their child's eczema symptoms with the responses from 26 participant surveys. Pre-survey responses were collected from 36 participants, though ten were lost to follow-up. Average POEM scores improved by 53%, while average HCS scores remained unchanged. Of seven completed in-person follow-up visits, six clinical progress notes documented improvement. Individualized eczema action plans can be seamlessly incorporated into primary and specialty care visits for pediatric patients suffering from eczema. Following a patient-specific eczema action plan may lessen the daily physical and mental burdens of uncontrolled eczema for children and parents, managing symptoms that chronically flare and recede. Furthermore, incorporating eczema action plans into practice potentially reduces the likely underestimated $5.3 billion economic disease burden of eczema on the U.S. healthcare system.

Keywords: atopic dermatitis, eczema action plan, eczema symptom management, pediatric eczema

Procedia PDF Downloads 135

Authors: Timothy Adam Boleratzky

Abstract:

The goal of this transformative endeavour lies in the repurposing of textile scraps, heralding a renaissance in the creation of wearable art. Through a judicious fusion of Life Cycle Assessment (LCA) methodologies and cutting-edge techniques, this research embarks upon a voyage of exploration, unraveling the intricate tapestry of environmental implications woven into the fabric of textile waste. Delving deep into the annals of empirical evidence and scholarly discourse, the study not only elucidates the urgent imperative for waste reduction strategies but also unveils the transformative potential inherent in embracing circular economy principles within the hallowed halls of fashion. As the research unfurls its sails, guided by the compass of sustainability, it traverses uncharted territories, charting a course toward a more enlightened and responsible fashion ecosystem. The canvas upon which this journey unfolds is richly adorned with insights gleaned from the crucible of experimentation, laying bare the myriad pathways toward waste minimisation and resource optimisation. From the adoption of recycling strategies to the cultivation of eco-friendly production techniques, the research endeavours to sculpt a blueprint for a more sustainable future, one stitch at a time. In this unfolding narrative, the role of wearable art emerges as a potent catalyst for change, transcending the boundaries of conventional fashion to embrace a more holistic ethos of sustainability. Through the alchemy of creativity and craftsmanship, discarded textile scraps are imbued with new life, morphing into exquisite creations that serve as both a testament to human ingenuity and a rallying cry for environmental preservation. Each thread, each stitch, becomes a silent harbinger of change, weaving together a tapestry of hope in a world besieged by ecological uncertainty. As the research journey culminates, its echoes resonate far beyond the confines of academia, reverberating through the corridors of industry and beyond. In its wake, it leaves a legacy of empowerment and enlightenment, inspiring a generation of designers, entrepreneurs, and consumers to embrace a more sustainable vision of fashion. For in the intricate interplay of threads and textiles lies the promise of a brighter, more resilient future, where beauty coexists harmoniously with responsibility and where fashion becomes not merely an expression of style but a celebration of sustainability.

Keywords: fabric-manipulation, sustainability, textiles, waste, wearable-art

Procedia PDF Downloads 44

Authors: Branislav Kovačević, Andrej Pilipović, Zoran Novčić, Marina Milović, Lazar Kesić, Milan Drekić, Saša Pekeč, Leopold Poljaković Pajnik, Saša Orlović

Abstract:

Poplars present one of the most important tree species used for phytoremediation in the northern hemisphere. They can be used either as direct “cleaners” of the contaminated soils or as buffer zones preventing the contaminant plume to the surrounding environment. In order to produce appropriate planting material for this purpose, there is a long process of the breeding of the most favorable candidates. Although the development of the poplar propagation technology has been evolving for decades, white poplar nursery production, as well as the establishment of short-rotation coppice plantations, still considerably depends on the success of hardwood cuttings’ survival. This is why easy rooting is among the most desirable properties in white poplar breeding. On the other hand, there are many opportunities for the optimization of the technological procedures in order to meet the demands of particular genotype (clonal technology). In this study the effect of the term of hardwood cuttings’ preparation of four white poplar clones on their survival and further growth of rooted cuttings in nursery conditions were tested. There were three terms of cuttings’ preparation: the beginning of February (2nd Feb 2023), the beginning of March (3rd Mar 2023) and the end of March (21nd Mar 2023), which is regarded as the standard term. The cuttings were stored in cool chamber at 2±2°C. All cuttings were planted on the same date (11th Apr 2023), in soil prepared with rotary tillage, and then cultivated by usual nursey procedures. According to the results obtained after the bud set (29th Sept 2023) there were significant differences in the survival and growth of rooted cuttings between examined terms of cutting preparation. Also, there were significant differences in the reaction of examined clones on terms of cutting preparation. In total, the best results provided cuttings prepared at the first term (2nd Feb 2023) (survival rate of 39.4%), while performance after two later preparation terms was significantly poorer (20.5% after second and 16.5% after third term). These results stress the significance of dormancy preservation in cuttings of examined white poplar clones for their survival, which could be especially important in context of climate change. Differences in clones’ reaction to term of cutting preparation suggest necessity of adjustment of the technology to the needs of particular clone i.e. design of clone specific technology.

Keywords: rooting, Populus alba, nursery, clonal technology

Procedia PDF Downloads 65

Authors: Gruffydd E. Jones

Abstract:

The world’s largest collection of historical, cultural, and heritage material is unarchived and undocumented in the hands of the public. Not only does this material represent the missing collections in heritage sector archives today, but it is also the key to providing a diverse range of communities with the means to express their history in their own words and to celebrate their unique, personal heritage. The People’s Collection Wales (PCW) acts as a platform on which the heritage of Wales and her people can be collated and shared, at the heart of which is a thriving community engagement programme across a network of museums, archives, and libraries. By providing communities with the archival skillset commonly employed throughout the heritage sector, PCW enables local projects, societies, and individuals to express their understanding of local heritage with their own voices, empowering communities to embrace their diverse and complex identities around Wales. Drawing on key examples from the project’s history, this paper will demonstrate the successful way in which museums have been developed as hubs for community engagement where the public was at the heart of collection and documentation activities, informing collection and curatorial policies to benefit both the institute and its local community. This paper will also highlight how collections from marginalised, under-represented, and minority communities have been published and celebrated extensively around Wales, including adoption by the education system in classrooms today. Any activity within the heritage sector, whether of collection, preservation, digitisation, or accessibility, should be considerate of community engagement opportunities not only to remain relevant but in order to develop as community hubs, pivots around which local heritage is supported and preserved. Attention will be drawn to our digitisation workflow, which, through training and support from museums and libraries, has allowed the public not only to become involved but to actively lead the contemporary evolution of documentation strategies in Wales. This paper will demonstrate how the PCW online access archive is promoting museum collections, encouraging user interaction, and providing an invaluable platform on which a broader community can inform, preserve and celebrate their cultural heritage through their own archival material too. The continuing evolution of heritage engagement depends wholly on placing communities at the heart of the sector, recognising their wealth of cultural knowledge, and developing the archival skillset necessary for them to become archival practitioners of their own.

Keywords: social history, cultural heritage, community heritage, museums, archives, libraries, community engagement, oral history, community archives

Procedia PDF Downloads 94

Authors: Hakima Althalb

Abstract:

Petroleum contamination of sandy soils is a severe environmental problem in Libya, but relatively little work has been carried out to optimize the bioremediation of such heavily contaminated soil, particularly at a pilot scale. The purpose of this research was to determine the potential for the microbial-based bioremediation of hydrocarbon-contaminated soil obtained from an oil refinery in Libya and to assess the potential of both ozonation and phytoremediation (both applied after initial bioremediation) to reduce residual hydrocarbon levels. Plots containing 500 kg soil (triplicates) (contaminated soil diluted with clean soil 50% volume) were set up, (designated as Land Treatment Units; LTUs) containing five different nutrient levels and mixtures (Urea + NPK (nitrogen; phosphor; potassium) mixtures) to obtain C:N:P ratios 100:10:1, and monitored for 90 days. Hydrocarbon levels, microbial numbers, and toxicity (EC50 using luminescent microbial based tests) were assessed. Hydrocarbon levels in non-diluted and diluted soil ranged from 20 733-22 366 mg/kg and from 16 000-17 000 mg/kg respectively. Although all the land treatment units revealed a significant hydrocarbon reduction over time, the highest reduction in hydrocarbon levels obtained was around 60%. For example, 63% hydrocarbon removal was observed using a mixture of urea and NPK with a C:N:P ratio of 100:10:1). Soil toxicity (as assessed using luminescence based toxicity assays) reduced in line with the reduction in total petroleum hydrocarbons observed. However, as relatively high residual TPH (total petroleum hydrocarbon) levels (ranging from 6033-14166mg/kg) were still present after initial bioremediation two ‘post-treatments’ (phytoremediation and ozonation) were attempted to remove residual hydrocarbons remaining. Five locally grown (agriculturally important) plant species were tested. The germination of all plants examined was strongly inhibited (80-100%) and seedlings failed to grow well in the contaminated soil, indicating that the previously bioremediated soils were still toxic to the plants. Subsequent ozonation followed by another bioremediation of soil was more successful than phytoremediation. But even the most promising successful treatment in this study (ozonation for 6 hours at 25ppm followed by bioremediation) still only removed approximately 31% of the residual hydrocarbons. Overall, this work showed that the bioremediation of such highly contaminated soils is difficult and that a combination of treatments would be required to achieve successful remediation. Even after initial dilution and bioremediation the soils remained toxic to plant growth and were therefore not suitable for phytoremediation.

Keywords: bioremediation, petroleum hydrocarbons, ozone, phytoremediation

Procedia PDF Downloads 183

Authors: Josiane N. Muller, Allan K. R. Galardo, Tatiane A. Barbosa, Evan P. Ferro, Wellington M. Dos Santos, Ana Paula S. A. Correa, Edinaldo C. Rego, Jose B. P. Lima

Abstract:

The susceptibility status of an insect population to any larvicide depends on several factors such includes genetic constitution, environmental conditions and others. The mosquito Aedes aegypti is the primary vector of three important viral diseases, Zika, Dengue, and Chikungunya. The frequent outbreaks of those diseases in different parts of Brazil demonstrate the importance of testing the susceptibility of vectors in different environments. Since the control of this mosquito leads to the control of disease, alternatives for vector control that value the different Brazilian environmental conditions are needed for effective actions. The aim of this study was to evaluate a new commercial formulation of Bacillus thuringiensis israelenses (DengueTech: Brazilian innovative technology) in the Brazilian Legal Amazon considering the climate conditions. Semi-field tests were conducted in the Institute of Scientific and Technological Research of the State of Amapa in two different environments, one in a shaded area and the other exposed to sunlight. The mosquito larvae were exposed to larvicide concentration and a control; each group was tested in three containers of 40 liters each. To assess persistence 50 third instar larvae of Aedes aegypti laboratory lineages (Rockefeller) and 50 larvae of Aedes aegypti collected in the municipality of Macapa, Brazil’s Amapa state, were added weekly and after 24 hours the mortality was assessed. In total 16 tests were performed, where 12 were done with replacement of water (1/5 of the volume, three times per week). The effectiveness of the product was determined through mortality of ≥ 80%, as recommend by the World Health Organization. The results demonstrated that high-water temperatures (26-35 °C) on the containers influenced the residual time of the product, where the maximum effect achieved was 21 days in the shaded area; and no effectiveness of 60 days was found in any of the tests, as expected according to the larvicide company. The test with and without water replacement did not present significant differences in the mortality rate. Considering the different environments and climate, these results stimulate the need to test larvicide and its effectiveness in specific environmental settings in order to identify the parameters required for better results. Thus, we see the importance of semi-field researches considering the local climate conditions for a successful control of Aedes aegypti.

Keywords: Aedes aegypti, bioassay, larvicida, vector control

Procedia PDF Downloads 129

Authors: Kirsty Biggs, Peter Larsen-Disney

Abstract:

Background: The UK cervical screening programme significantly reduces cancer mortality through the early detection of abnormal cells. Despite this, over a quarter of eligible women choose not to attend their appointment. Objective: To qualitatively explore patients’ barriers to attending cervical smear appointments and identify key trends of cervical screening behaviour, knowledge, and attitudes in primary and secondary care. Methods: A cross-sectional study was conducted to evaluate smear services in Brighton and Hove using questionnaires in general practice and colposcopy. 226 patients participated in the voluntary questionnaire between 10/11/2017 and 02/02/2018. 118 patients were recruited from general practice surgeries and 108 from the colposcopy department. Women were asked about their smear knowledge, self-perceived risks factors, prior experiences and reasons for non-attendance. Demographic data was also collected. Results: Approximately a third of women did not engage in smear testing services. This was consistent across primary and secondary care groups. Over 90% were aware of the role of the screening process in relation to cervical cancer; however, over two thirds believed the smear was also a tool to screen for other pathologies. The most commonly cited reasons for non-attendance were negative emotions or previous experiences. Inconvenient appointment times were also commonly described. In a comparison of attenders versus non-attenders previous negative experiences (p < 0.01) and number of identified risk factors (p = 0.02) were statistically significant with non-attenders describing more prior negative smears and identifying more risk factors. Smear knowledge, risk perception and perceived importance of screening were not significant. Negative previous experiences were described in relation to poor bedside manner, pain, embarrassment and staff competency. Conclusions: In contrary to the literature, our white Caucasian cohort experienced significant barriers to accessing smear services. Women’s prior negative experiences are overriding their perceived importance to attend the screening programme; therefore, efforts need to focus on improving clinical experiences through auditing tools, training and providing a supportive appointment setting. Positive changes can also be expected by improving appointment availabilities with extended hours and self-booking systems.

Keywords: barriers, cervical, Papanicolaou, screening, smear

Procedia PDF Downloads 149

Authors: Gabrielle Brand, Christopher Etherton-Beer

Abstract:

The learning landscape of higher education environment is changing, with an increased focus over the past decade on how educators might begin to cultivate reflective skills in health professions students. In addition, changing professional requirements demand that health professionals are adequately prepared to practice in today’s complex Australian health care systems, including responding to changing demographics of population ageing. To counteract a widespread perception of health professions students’ disinterest in caring for older persons, the authors will report on an exploratory, mixed method research study that used photographs, narrative and small group work to enhance medical and nursing students’ reflective learning experience. An innovative photo-elicitation technique and reflective questioning prompts were used to increase engagement, and challenge students to consider new perspectives (around ageing) by constructing shared storylines in small groups. The qualitative themes revealed how photographs, narratives and small group work created learning spaces for reflection whereby students could safely explore their own personal and professional values, beliefs and perspectives around ageing. By providing the space for reflection, the students reported how they found connection and meaning in their own learning through a process of self-exploration that often challenged their assumptions of both older people and themselves as future health professionals. By integrating cognitive and affective elements into the learning process, this research demonstrates the importance of embedding visual methodologies that enhance reflection and transformative learning. The findings highlight the importance of integrating the arts into predominantly empirically driven health professional curricula and can be used as a catalyst for individual and/or collective reflection which can potentially enhance empathy, insight and understanding of the lived experiences of older patients. Based on these findings, the authors have developed ‘Depth of Field: Exploring Ageing’ an innovative, interprofessional, digital reflective learning resource that uses Prezi Inc. software (storytelling tool that presents ideas on a virtual canvas) to enhance students’ reflective capacity in the higher education environment.

Keywords: narrative, photo-elicitation, reflective learning, qualitative research

Procedia PDF Downloads 285

Authors: Mei Lin, Chang Liu

Abstract:

Argumentative writing is the most prevalent genre in diverse writing tests. How to construct academic arguments is often regarded as a difficult task by most English as a foreign language (EFL) learners. A failure to generate enough ideas and organise them coherently and logically as well as a lack of competence in supporting their arguments with relevant evidence are frequent problems faced by EFL learners when approaching an English argumentative writing task. Overall, these problems are closely related to planning, and planning an argumentative writing at pre-writing stage plays a vital role in a good academic essay. However, how teachers can effectively guide students to generate ideas is rarely discussed in planning English argumentative writing, apart from brainstorming. Brainstorming has been a common practice used by teachers to help students generate ideas. However, some limitations of brainstorming suggest that it can help students generate many ideas, but ideas might not necessarily be coherent and logic, and could sometimes impede production. It calls for a need to explore effective instructional strategies at pre-writing stage of English argumentative writing. This paper will first examine how a Six Thinking Hats approach can be used to provide a dialogic space for EFL learners to experience and collaboratively generate ideas from multiple perspectives at pre-writing stage. Part of the findings of the impact of a twelve-week intervention (from March to July 2021) on students learning to generate ideas through engaging in group discussions of using Six Thinking Hats will then be reported. The research design is based on the sociocultural theory. The findings present evidence from a mixed-methods approach and fifty-nine participants from two first-year undergraduate natural classes in a Chinese university. Analysis of pre- and post- questionnaires suggests that participants had a positive attitude toward the Six Thinking Hats approach. It fosters their understanding of prewriting and argumentative writing, helps them to generate more ideas not only from multiple perspectives but also in a systematic way. A comparison of participants writing plans confirms an improvement in generating counterarguments and rebuttals to support their arguments. Above all, visual and transcripts data of group discussion collected from different weeks throughout the intervention enable teachers and researchers to ‘see’ the hidden process of learning to generate ideas in action.

Keywords: argumentative writing, innovative pedagogy, six thinking hats, dialogic space, prewriting, higher education

Procedia PDF Downloads 87

Authors: Flavien Marteau, Pedro Affonso Nóbrega, Pascal Biwole, Nicolas Autrusson, Iona De Bievre, Christian Beauger

Abstract:

Effective water management is essential for the optimal performance of fuel cells. For this reason, many vehicle systems use a membrane humidifier, a passive device that humidifies the air before the cathode inlet. Although they offer good performance, humidifiers are voluminous, costly, and fragile, hence the desire to find an alternative. Direct water injection could be an option, although this method lacks maturity. It consists of injecting liquid water as a spray in the dry heated air coming out from the compressor. This work focuses on the evaluation of direct water injection and its performance compared to the membrane humidifier selected as a reference. Two architectures were experimentally tested to humidify an industrial 2 kW short stack made up of 20 cells of 150 cm² each. For the reference architecture, the inlet air is humidified with a commercial membrane humidifier. For the direct water injection architecture, a pneumatic nozzle was selected to generate a fine spray in the air flow with a Sauter mean diameter of about 20 μm. Initial performance was compared over the entire range of current based on polarisation curves. Then, the influence of various parameters impacting water management was studied, such as the temperature, the gas stoichiometry, and the water injection flow rate. The experimental results obtained confirm the possibility of humidifying the fuel cell using direct water injection. This study, however shows the limits of this humidification method, the mean cell voltage being significantly lower in some operating conditions with direct water injection than with the membrane humidifier. The voltage drop reaches 30 mV per cell (4 %) at 1 A/cm² (1,8 bara, 80 °C) and increases in more demanding humidification conditions. It is noteworthy that the heat of compression available is not enough to evaporate all the injected liquid water in the case of DWI, resulting in a mix of liquid and vapour water entering the fuel cell, whereas only vapour is present with the humidifier. Variation of the injection flow rate shows that part of the injected water is useless for humidification and seems to cross channels without reaching the membrane. The stack was successfully humidified thanks to direct water injection. Nevertheless, our work shows that its implementation requires substantial adaptations and may reduce the fuel cell stack performance when compared to conventional membrane humidifiers, but opportunities for optimisation have been identified.

Keywords: cathode humidification, direct water injection, membrane humidifier, proton exchange membrane fuel cell

Procedia PDF Downloads 44

Authors: Oladele V. Adeniyi, B. Longo-Mbenza, Daniel T. Goon

Abstract:

Background: Lipids are often low or in the normal ranges and controversial in the atherogenesis among Black Africans. The effect of the severity of obesity on some traditional and novel cardiovascular disease risk factors is unclear before and after a diet and exercise maintenance programme among obese black South Africans with type 2 diabetes mellitus (T2DM). Therefore, this study aimed to identify the risk factors to discriminate obesity classes among patients with T2DM before and after a diet and exercise programme. Methods: This interventional cohort of Black South Africans with T2DM was followed by a very – low calorie diet and exercise programme in Mthatha, between August and November 2013. Gender, age, and the levels of body mass index (BMI), blood pressure, monthly income, daily frequency of meals, blood random plasma glucose (RPG), serum creatinine, total cholesterol (TC), triglycerides (TG), LDL –C, HDL – C, Non-HDL, ratios of TC/HDL, TG/HDL, and LDL/HDL were recorded. Univariate analysis (ANOVA) and multivariate discriminant analysis were performed to separate obesity classes: normal weight (BMI = 18.5 – 24.9 kg/m2), overweight (BMI = 25 – 29.9 kg/m2), obesity Class 1 (BMI = 30 – 34.9 kg/m2), obesity Class 2 (BMI = 35 – 39.9 kg/m2), and obesity Class 3 (BMI ≥ 40 kg/m2). Results: At the baseline (1st Month September), all 327 patients were overweight/obese: 19.6% overweight, 42.8% obese class 1, 22.3% obese class 2, and 15.3% obese class 3. In discriminant analysis, only systolic blood pressure (SBP with positive association) and LDL/HDL ratio (negative association) significantly separated increasing obesity classes. At the post – evaluation (3rd Month November), out of all 327 patients, 19.9%, 19.3%, 37.6%, 15%, and 8.3% had normal weight, overweight, obesity class 1, obesity class 2, and obesity class 3, respectively. There was a significant negative association between serum creatinine and increase in BMI. In discriminant analysis, only age (positive association), SBP (U – shaped relationship), monthly income (inverted U – shaped association), daily frequency of meals (positive association), and LDL/HDL ratio (positive association) classified significantly increasing obesity classes. Conclusion: There is an epidemic of diabesity (Obesity + T2DM) in this Black South Africans with some weight loss. Further studies are needed to understand positive or negative linear correlations and paradoxical curvilinear correlations between these markers and increase in BMI among black South African T2DM patients.

Keywords: atherogenic dyslipidaemia, dietary interventions, obesity, south africans

Procedia PDF Downloads 367

Authors: Rui Teixeira, Alan O’Connor, Maria Nogal

Abstract:

The statistical theory of extreme events is progressively a topic of growing interest in all the fields of science and engineering. The changes currently experienced by the world, economic and environmental, emphasized the importance of dealing with extreme occurrences with improved accuracy. When it comes to the design of offshore structures, particularly offshore wind turbines, the importance of efficiently characterizing extreme events is of major relevance. Extreme events are commonly characterized by extreme values theory. As an alternative, the accurate modeling of the tails of statistical distributions and the characterization of the low occurrence events can be achieved with the application of the Peak-Over-Threshold (POT) methodology. The POT methodology allows for a more refined fit of the statistical distribution by truncating the data with a minimum value of a predefined threshold u. For mathematically approximating the tail of the empirical statistical distribution the Generalised Pareto is widely used. Although, in the case of the exceedances of significant wave data (H_s) the 2 parameters Weibull and the Exponential distribution, which is a specific case of the Generalised Pareto distribution, are frequently used as an alternative. The Generalized Pareto, despite the existence of practical cases where it is applied, is not completely recognized as the adequate solution to model exceedances over a certain threshold u. References that set the Generalised Pareto distribution as a secondary solution in the case of significant wave data can be identified in the literature. In this framework, the current study intends to tackle the discussion of the application of statistical models to characterize exceedances of wave data. Comparison of the application of the Generalised Pareto, the 2 parameters Weibull and the Exponential distribution are presented for different values of the threshold u. Real wave data obtained in four buoys along the Irish coast was used in the comparative analysis. Results show that the application of the statistical distributions to characterize significant wave data needs to be addressed carefully and in each particular case one of the statistical models mentioned fits better the data than the others. Depending on the value of the threshold u different results are obtained. Other variables of the fit, as the number of points and the estimation of the model parameters, are analyzed and the respective conclusions were drawn. Some guidelines on the application of the POT method are presented. Modeling the tail of the distributions shows to be, for the present case, a highly non-linear task and, due to its growing importance, should be addressed carefully for an efficient estimation of very low occurrence events.

Keywords: extreme events, offshore structures, peak-over-threshold, significant wave data

Procedia PDF Downloads 273