Search results for: cross section loss
2635 Assessing the Effect of the Position of the Cavities on the Inner Plate of the Steel Shear Wall under Time History Dynamic Analysis
Authors: Masoud Mahdavi, Mojtaba Farzaneh Moghadam
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The seismic forces caused by the waves created in the depths of the earth during the earthquake hit the structure and cause the building to vibrate. Creating large seismic forces will cause low-strength sections in the structure to suffer extensive surface damage. The use of new steel shear walls in steel structures has caused the strength of the building and its main members (columns) to increase due to the reduction and depreciation of seismic forces during earthquakes. In the present study, an attempt was made to evaluate a type of steel shear wall that has regular holes in the inner sheet by modeling the finite element model with Abacus software. The shear wall of the steel plate, measuring 6000 × 3000 mm (one floor) and 3 mm thickness, was modeled with four different pores with a cross-sectional area. The shear wall was dynamically subjected to a time history of 5 seconds by three accelerators, El Centro, Imperial Valley and Kobe. The results showed that increasing the distance between the geometric center of the hole and the geometric center of the inner plate in the steel shear wall (increasing the RCS index) caused the total maximum acceleration to be transferred from the perimeter of the hole to horizontal and vertical beams. The results also show that there is no direct relationship between RCS index and total acceleration in steel shear wall and RCS index is separate from the peak ground acceleration value of earthquake.Keywords: hollow steel plate shear wall, time history analysis, finite element method, abaqus software
Procedia PDF Downloads 1052634 Remittances and Water Access: A Cross-Sectional Study of Sub Saharan Africa Countries
Authors: Narges Ebadi, Davod Ahmadi, Hiliary Monteith, Hugo Melgar-Quinonez
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Migration cannot necessarily relieve pressure on water resources in origin communities, and male out-migration can increase the water management burden of women. However, inflows of financial remittances seem to offer possibilities of investing in improving drinking-water access. Therefore, remittances may be an important pathway for migrants to support water security. This paper explores the association between water access and the receipt of remittances in households in sub-Saharan Africa. Data from round 6 of the 'Afrobarometer' surveys in 2016 were used (n= 49,137). Descriptive, bivariate and multivariate statistical analyses were carried out in this study. Regardless of country, findings from descriptive analyses showed that approximately 80% of the respondents never received remittance, and 52% had enough clean water. Only one-fifth of the respondents had piped water supply inside the house (19.9%), and approximately 25% had access to a toilet inside the house. Bivariate analyses revealed that even though receiving remittances was significantly associated with water supply, the strength of association was very weak. However, other factors such as the area of residence (rural vs. urban), cash income frequencies, electricity access, and asset ownership were strongly associated with water access. Results from unadjusted multinomial logistic regression revealed that the probability of having no access to piped water increased among remittance recipients who received financial support at least once a month (OR=1.324) (p < 0.001). In contrast, those not receiving remittances were more likely to regularly have a water access concern (OR=1.294) (p < 0.001), and not have access to a latrine (OR=1.665) (p < 0.001). In conclusion, receiving remittances is significantly related to water access as the strength of odds ratios for socio-demographic factors was stronger.Keywords: remittances, water access, SSA, migration
Procedia PDF Downloads 1852633 The Impact of COVID-19 on the Mental Health of Residents of Saudi Arabia
Authors: Khaleel Alyahya, Faizah Alotaibi
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The coronavirus disease 19 (COVID-19) pandemic has caused an increase in general fear and anxiety around the globe. With the public health measures, including lockdown and travel restrictions, the COVID-19 period further resulted in a sudden increase in the vulnerability of people too ill mental health. This becomes greater among individuals who have a history of mental illness or are undergoing treatment and do not have easy access to medication and medical consultations. The study aims to measure the impact of COVID-19 and the degree of distress with the DASS scale on the mental health of residents living in Saudi Arabia. The study is a quantitative, observational, and cross-sectional conducted in Saudi Arabia to measure the impact of COVID-19 on the mental health of both citizens and residents of Saudi Arabia during pandemics. The study ran from February 2021 to June 2021, and a validated questionnaire was used. The targeted population of the study was Saudi citizens and non-Saudi residents. A sample size of 800 participants was calculated with a single proportion formula at 95% level of significance and 5% allowable error. The result revealed that participants who were always doing exercise experienced the lowest level of depression, anxiety, and stress. The highest prevalence of severe and extremely severe depression was among participants who sometimes do exercise at 53.2% for each. Similar results were obtained for anxiety and stress, where the extremely severe form was reported by those who sometimes did exercise at 54.8% and 72.2%, respectively. There was an inverse association between physical activity levels and levels of depression, anxiety, and stress during the COVID-19. Similarly, the levels of depression, anxiety, and stress differed significantly according to the exercise frequency during COVID-19.Keywords: mental, COVID-19, pandemic, lockdown, depression, anxiety, stress
Procedia PDF Downloads 1072632 Sensor and Actuator Fault Detection in Connected Vehicles under a Packet Dropping Network
Authors: Z. Abdollahi Biron, P. Pisu
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Connected vehicles are one of the promising technologies for future Intelligent Transportation Systems (ITS). A connected vehicle system is essentially a set of vehicles communicating through a network to exchange their information with each other and the infrastructure. Although this interconnection of the vehicles can be potentially beneficial in creating an efficient, sustainable, and green transportation system, a set of safety and reliability challenges come out with this technology. The first challenge arises from the information loss due to unreliable communication network which affects the control/management system of the individual vehicles and the overall system. Such scenario may lead to degraded or even unsafe operation which could be potentially catastrophic. Secondly, faulty sensors and actuators can affect the individual vehicle’s safe operation and in turn will create a potentially unsafe node in the vehicular network. Further, sending that faulty sensor information to other vehicles and failure in actuators may significantly affect the safe operation of the overall vehicular network. Therefore, it is of utmost importance to take these issues into consideration while designing the control/management algorithms of the individual vehicles as a part of connected vehicle system. In this paper, we consider a connected vehicle system under Co-operative Adaptive Cruise Control (CACC) and propose a fault diagnosis scheme that deals with these aforementioned challenges. Specifically, the conventional CACC algorithm is modified by adding a Kalman filter-based estimation algorithm to suppress the effect of lost information under unreliable network. Further, a sliding mode observer-based algorithm is used to improve the sensor reliability under faults. The effectiveness of the overall diagnostic scheme is verified via simulation studies.Keywords: fault diagnostics, communication network, connected vehicles, packet drop out, platoon
Procedia PDF Downloads 2422631 Risk Factors and Epidemiological Aspects of Cleft Lip and Palate and Associated Orthodontic Anomalies in Western Algeria
Authors: Beghdadi Chafika, Mrabet Sonia, Heroual Nabila, Ahmed Fouatih Noureddine
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Introduction: Cleft lip and palate are the most common congenital malformations of the orofacial sphere, accounting for one in every 700 births worldwide. They have a multifactorial origin, requiring multidisciplinary intervention from birth to adulthood. In the absence of work in Algeria on this pathology, we undertook a study to describe the epidemiological aspects and determine the risk factors. Methodology: This is a cross-sectional descriptive study from February 2018 to June 2021, including all cleft patients referred to and or followed up for management at the ODF/ CHU d'Oran department. Results: 260 patients were included. Males predominated (sex ratio=1.17). The mean age of the patients was 1.65 ± 2.6 years, most of whom lived in Oran. The mean age of the mothers was 32.5 years, and 37 years for the fathers. More than half of all cases had cleft lip and palate, with a predominance on the left side. Consanguinity was found in 20%. Mothers had more medical history than fathers. Stress, emotional shock, active smoking in the father, low socio-economic status, and vitamin deficiency in the mother were the most common factors. Both dentitions were affected by various dental anomalies, the most frequent of which was a numerical anomaly (31.6%), followed by the delayed eruption (23.1%) with the absence of inclusion and transposition. All functions have been disrupted to varying degrees, depending on the severity of the damage. Because of the anatomical and physiological characteristics of clefts, any disturbance during embryogenesis alters the course of the latter, leading to congenital anomalies. Conclusion: The study enabled us to draw up a profile of cleft lip and palate and to identify certain risk factors to guide the main lines of prevention.Keywords: cleft lip and palate, dental anomalies, risk factors, orthodontics
Procedia PDF Downloads 122630 [Keynote Talk]: Quest for Sustainability in the Midst of Conflict Between Climate and Energy Security
Authors: Deepak L. Waikar
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Unprecedented natural as well as human made disasters have been responsible for loss of hundreds of thousands of lives, injury & displacement of millions of people and damages in billions of dollars in various parts of the world. Scientists, experts, associations and united nation have been warning about colossal disregard for human safety and environment in exploiting natural resources for insatiable greed for economic growth and rising lavish life style of the rich. Usual blame game is routinely played at international forums & summits by vested interests in developing and developed nations, while billions of people continue to suffer in abject energy poverty. Energy security, on the other hand, is becoming illusive with the dominance of few players in the market, poor energy governance mechanisms, volatile prices and geopolitical conflicts in supply chain. Conflicting scenarios have been cited as one of the major barriers for transformation to a low carbon economy. Policy makers, researchers, academics, businesses, industries and communities have been evaluating sustainable alternatives, albeit at snail’s pace. This presentation focuses on technologies, energy governance, policies & practices, economics and public concerns about safe, prudent & sustainable harnessing of energy resources. Current trends and potential research & development projects in power & energy sectors which students can undertake will be discussed. Speaker will highlight on how youths can be engaged in meaningful, safe, enriching, inspiring and value added self-development programmes in our quest for sustainability in the midst of conflict between climate and energy security.Keywords: clean energy, energy policy, energy security, sustainable energy
Procedia PDF Downloads 4902629 Specific Language Impirment in Kannada: Evidence Form a Morphologically Complex Language
Authors: Shivani Tiwari, Prathibha Karanth, B. Rajashekhar
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Impairments of syntactic morphology are often considered central in children with Specific Language Impairment (SLI). In English and related languages, deficits of tense-related grammatical morphology could serve as a clinical marker of SLI. Yet, cross-linguistic studies on SLI in the recent past suggest that the nature and severity of morphosyntactic deficits in children with SLI varies with the language being investigated. Therefore, in the present study we investigated the morphosyntactic deficits in a group of children with SLI who speak Kannada, a morphologically complex Dravidian language spoken in Indian subcontinent. A group of 15 children with SLI participated in this study. Two more groups of typical developing children (15 each) matched for language and age to children with SLI, were included as control participants. All participants were assessed for morphosyntactic comprehension and expression using standardized language test and a spontaneous speech task. Results of the study showed that children with SLI differed significantly from age-matched but not language-matched control group, on tasks of both comprehension and expression of morphosyntax. This finding is, however, in contrast with the reports of English-speaking children with SLI who are reported to be poorer than younger MLU-matched children on tasks of morphosyntax. The observed difference in impairments of morphosyntax in Kannada-speaking children with SLI from English-speaking children with SLI is explained based on the morphological richness theory. The theory predicts that children with SLI perform relatively better in morphologically rich language due to occurrence of their frequent and consistent features that mark the morphological markers. The authors, therefore, conclude that language-specific features do influence manifestation of the disorder in children with SLI.Keywords: specific language impairment, morphosyntax, Kannada, manifestation
Procedia PDF Downloads 2492628 Evaluation of Food Safety and Security Practices in Midday Meal Programmes in Rural Areas of Beed District
Authors: Nuzhat Sultana M. B.
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Children are high-risk population in terms of food born illnesses. Food safety and security are the most important aspect of the success of midday meal programmes. Improper holding temperatures, cross-contamination and poor personal hygiene of food handlers are the main causes for the prevalence of pathogenic microbes in the food servicing areas. Two hundred and fifty preschool children in the age of 3 to 6 years from urban and rural anganwadies (pre school center) of Beed district were selected. Nutritional status of preschool children were assessed by anthropometrical and clinical measurement. The study assessed the food safety and security with the help of personal hygiene and other safety measures maintained by the food personnel working for midday meal programme, supplying mid meals to children in govt. anganwadies (pre school center). The hygiene level, sanitary condition and microbial quality of food and water, pathological health examination of food handlers were assessed with the help of checklist. A questionnaire was designed to evaluate knowledge, attitude, and practices of food handlers. Results of the study show that the nutritional and health status of rural and urban preschool children was very poor. Many of the food handlers were not aware of general knowledge and hygiene practices to be followed during food preparation areas. An intervention programme of education and importing training at workplaces has shown a positive impact on the outcome of safety and security practices and safe, hygienic practices of food handlers at workplace.Keywords: food, health, preschool children, safety, security
Procedia PDF Downloads 2072627 Effect of Thermal Treatment on Phenolic Content, Antioxidant, and Alpha-Amylase Inhibition Activities of Moringa stenopetala Leaves
Authors: Daniel Assefa, Engeda Dessalegn, Chetan Chauhan
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Moringa stenopetala is a socioeconomic valued tree that is widely available and cultivated in the Southern part of Ethiopia. The leaves have been traditionally used as a food source with high nutritional and medicinal values. The present work was carried out to evaluate the effect of thermal treatment on the total phenolic content, antioxidant and alpha-amylase inhibition activities of aqueous leaf extracts during maceration and different decoction time interval (5, 10 and 15 min). The total phenolic content was determined by the Folin-ciocalteu methods whereas antioxidant activities were determined by 2,2-diphenyl-1-picryl-hydrazyl(DPPH) radical scavenging, reducing power and ferrous ion chelating assays and alpha-amylase inhibition activity was determined using 3,5-dinitrosalicylic acid method. Total phenolic content ranged from 34.35 to 39.47 mgGAE/g. Decoction for 10 min extract showed ferrous ion chelating (92.52), DPPH radical scavenging (91.52%), alpha-amylase inhibition (69.06%) and ferric reducing power (0.765), respectively. DPPH, reducing power and alpha-amylase inhibition activities showed positive linear correlation (R2=0.853, R2= 0.857 and R2=0.930), respectively with total phenolic content but ferrous ion chelating activity was found to be weakly correlated (R2=0.481). Based on the present investigation, it could be concluded that major loss of total phenolic content, antioxidant and alpha-amylase inhibition activities of the crude leaf extracts of Moringa stenopetala leaves were observed at decoction time for 15 min. Therefore, to maintain the total phenolic content, antioxidant, and alpha-amylase inhibition activities of leaves, cooking practice should be at the optimum decoction time (5-10 min).Keywords: alpha-amylase inhibition, antioxidant, Moringa stenopetala, total phenolic content
Procedia PDF Downloads 3662626 Relation between Biochemical Parameters and Bone Density in Postmenopausal Women with Osteoporosis
Authors: Shokouh Momeni, Mohammad Reza Salamat, Ali Asghar Rastegari
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Background: Osteoporosis is the most prevalent metabolic bone disease in postmenopausal women associated with reduced bone mass and increased bone fracture. Measuring bone density in the lumbar spine and hip is a reliable measure of bone mass and can therefore specify the risk of fracture. Dual-energy X-ray absorptiometry(DXA) is an accurate non-invasive system measuring the bone density, with low margin of error and no complications. The present study aimed to investigate the relationship between biochemical parameters with bone density in postmenopausal women. Materials and methods: This cross-sectional study was conducted on 87 postmenopausal women referred to osteoporosis centers in Isfahan. Bone density was measured in the spine and hip area using DXA system. Serum levels of calcium, phosphorus, alkaline phosphatase and magnesium were measured by autoanalyzer and serum levels of vitamin D were measured by high-performance liquid chromatography(HPLC). Results: The mean parameters of calcium, phosphorus, alkaline phosphatase, vitamin D and magnesium did not show a significant difference between the two groups(P-value>0.05). In the control group, the relationship between alkaline phosphatase and BMC and BA in the spine was significant with a correlation coefficient of -0.402 and 0.258, respectively(P-value<0.05) and BMD and T-score in the femoral neck area showed a direct and significant relationship with phosphorus(Correlation=0.368; P-value=0.038). There was a significant relationship between the Z-score with calcium(Correlation=0.358; P-value=0.044). Conclusion: There was no significant relationship between the values of calcium, phosphorus, alkaline phosphatase, vitamin D and magnesium parameters and bone density (spine and hip) in postmenopausKeywords: osteoporosis, menopause, bone mineral density, vitamin d, calcium, magnesium, alkaline phosphatase, phosphorus
Procedia PDF Downloads 1832625 Predicting the Human Impact of Natural Onset Disasters Using Pattern Recognition Techniques and Rule Based Clustering
Authors: Sara Hasani
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This research focuses on natural sudden onset disasters characterised as ‘occurring with little or no warning and often cause excessive injuries far surpassing the national response capacities’. Based on the panel analysis of the historic record of 4,252 natural onset disasters between 1980 to 2015, a predictive method was developed to predict the human impact of the disaster (fatality, injured, homeless) with less than 3% of errors. The geographical dispersion of the disasters includes every country where the data were available and cross-examined from various humanitarian sources. The records were then filtered into 4252 records of the disasters where the five predictive variables (disaster type, HDI, DRI, population, and population density) were clearly stated. The procedure was designed based on a combination of pattern recognition techniques and rule-based clustering for prediction and discrimination analysis to validate the results further. The result indicates that there is a relationship between the disaster human impact and the five socio-economic characteristics of the affected country mentioned above. As a result, a framework was put forward, which could predict the disaster’s human impact based on their severity rank in the early hours of disaster strike. The predictions in this model were outlined in two worst and best-case scenarios, which respectively inform the lower range and higher range of the prediction. A necessity to develop the predictive framework can be highlighted by noticing that despite the existing research in literature, a framework for predicting the human impact and estimating the needs at the time of the disaster is yet to be developed. This can further be used to allocate the resources at the response phase of the disaster where the data is scarce.Keywords: disaster management, natural disaster, pattern recognition, prediction
Procedia PDF Downloads 1572624 Sib-Care and Attachment in Zambia and the Netherlands
Authors: Haatembo Mooya
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Cross-culturally, exclusive maternal care of infants is an exception, rather than a rule. In most traditional non-Western societies, child care is shared within the family while in most middle class Western societies parents tend to rely more on ‘hired hands’ for support. In both contexts however, a common caregiver is the sibling. Despite this, the phenomenon of sib-care has remained relatively understudied. Cultural and gender differences in sib-care and attachment were explored using a retrospective survey instrument comparing Zambian and Dutch college students. The total study sample (N = 394) comprised of 200 Zambian students from the University of Zambia and 194 Dutch students from Leiden University, the Netherlands. We tested four main hypotheses. Firstly, we hypothesized that the Zambian subjects performed more sib-care than Dutch subjects. Secondly we hypothesized that female participants performed more sib-care than males participants, both among the Zambian and Dutch subjects, especially when parents are not at home. Thirdly, we hypothesized that larger family size was associated with more sib-care. Finally, we hypothesized that securely attached participants performed more sib-care than their less securely attached peers. Results indicated that sib-care was prevalent in both Zambian and Dutch samples. Zambian subjects performed more sib-care than Dutch subjects, with females performing more sib-care than males, both when parents were at home (F(2, 244) = 62.09, p < .01) and when parents were not at home (F(2, 237) = 51.28, p < .01). We also found that family size and attachment related avoidance and anxiety were not significant predictors of sib-care. It is concluded that sib-care is understudied, not only in Africa but also in Western societies and that females perform more sib-care than males, especially when the parents are not at home. In addition, attachment related avoidance and anxiety appear to be more related to the quality than the quantity of sib-care provided.Keywords: sibling, sib-care, attachment, Africa, Zambia, the Netherlands
Procedia PDF Downloads 6522623 Comparing Phonological Processes in Persian-Arabic Bilingual Children and Monolingual Children
Authors: Vafa Delphi, Maryam Delphi, Talieh Zarifian, Enayatolah Bakhshi
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Background and Aim: Bilingualism is a common phenomenon in many countries of the world and May be consistent consonant errors in the speech of bilingual children. The aim of this study was to evaluate Phonological skills include occurrence proportion, frequency and type of phonological processes in Persian-Arabic speaking children in Ahvaz city, the center of Khuzestan. Method: This study is descriptive-analytical and cross-sectional. Twenty-eight children aged 36-48 months were divided into two groups Persian monolingual and Persian-Arabic bilingual: (14 participants in each group). Sampling was recruited randomly based on inclusion criteria from kindergartens of the Ahvaz city in Iran. The tool of this study was the Persian Phonological Test (PPT), a subtest of Persian Diagnostic Evaluation Articulation and Phonological test. In this test, Phonological processes were investigated in two groups: structure and substitution processes. Data was investigated using SPSS software and the U Mann-Whitney test. Results: The results showed that the proportion occurrence of substitution process was significantly different between two groups of monolingual and bilingual (P=0/001), But the type of phonological processes didn’t show a significant difference in both monolingual and bilingual children of the Persian-Arabic.The frequency of phonological processes is greater in bilingual children than monolingual children. Conclusion: The study showed that bilingualism has no effect on type of phonological processes, but this can be effective on the frequency of processes. Since the type of phonological processes in bilingual children is similar to monolingual children So we can conclude the Persian_arabic bilingual children's phonological system is similar to monolingual children.Keywords: Persian-Arabic bilingual child, phonological processes, the proportion occurrence of syllable structure, the proportion occurrence of substitution
Procedia PDF Downloads 3212622 Translation of Culture-Specific References in the Turkish Translation of Shakespeare's Macbeth
Authors: Feride Sumbul
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Drama is a literary genre that mirrors the people and society and transfers the human nature and life to the reader or the audience within its own social-cultural structure. Each play takes on a new reality in the time and culture of the staging, and each performance actually brings a new interpretation to the play. Similarly, each translation adds a new meaning to the source text. In other words, the translated theatrical text transcends the boundaries of its language and culture and finds a new interpretation. Thus the translation of drama takes place as a transfer from one culture to another as a cross cultural communication. In this context, translating culture specific references play a key role in terms of reflecting cultural aspects of a target society. This study aims to explore the use of Venuti's translation principles of domestication and foreignization in the transfer of culture specific references in the Turkish translation of Shakespeare's Macbeth. Macbeth is to be compared with its Turkish version in terms of the transference of culture specific references such as religious, witchcraft, and mythological, which have no equivalent in the target language and culture. To evaluate these principles of Venuti, Davies’s translation strategies are also conducted. As a method, for the most part, he predominantly uses Davies’ method of ‘addition’ through adding extra information in the notes. For instance, rather than finding the Turkish renderings of them, the translator mostly chooses to transfer witchcraft references through retaining them in the target text, but he mainly adds extra information about the references in the notes. Therefore, the translator Nutku mostly uses Venuti’s translation principle of foreignization so that he preserves the foreignness of the theatrical text.Keywords: drama translation, theatrical texts, culture specific references, Macbeth
Procedia PDF Downloads 1622621 How Strategic Urban Design Promote Sustainable Urban Mobility: A Comparative Analysis of Cities from Global North and Global South
Authors: Rati Sandeep Choudhari
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Mobility flows are considered one of the most important elements of urbanisation, with transport infrastructure serving as a backbone of urban fabrics. Although rapid urbanisation and changing land use patterns have led to an increase in urban mobility levels around the globe, mobility, in general, has become an unpleasant experience for city dwellers, making locations around the city inconvenient to access. With public transport featured in almost every sustainable mobility plan in developing countries, the intermodality and integration with appropriate non–motorised transport infrastructure is often neglected. As a result, people choose to use private cars and two-wheelers to travel, rendering public transit systems underutilised, and encroaching onto pedestrian space on streets, thus making urban mobility unsafe and inconvenient for a major section of society. On the other hand, cities in the West, especially in Europe, depend heavily on inter–modal transit systems, allowing people to shift between metros, buses, trams, walking, and cycling to access even the remote locations of the city. Keeping accessibility as the focal point while designing urban mobility plans and policies, these cities have appropriately refined their urban form, optimised urban densities, developed a multimodal transit system, and adopted place-making strategies to foster a sense of place, thus, improving the quality of urban mobility experience in cities. Using a qualitative research approach, the research looks in detail into the existing literature on what kind of strategies can be applied to improve the urban mobility experience for city dwellers. It further studies and draws out a comparative analysis of cities in both developed and developing parts of the world where these strategies have been used to create people-centric mobility systems, fostering a sense of place with respect to urban mobility and how these strategies affected their social, economic, and environmental dynamics. The examples reflect on how different strategies like redefining land use patterns to form close knit neighbourhoods, development of non – motorise transit systems, and their integration with public transport infrastructure and place-making approach has helped in enhancing the quality and experience of mobility infrastructure in cities. The research finally concludes by laying out strategies that can be adopted by cities of the Global South to develop future mobility systems in a people-centric and sustainable way.Keywords: urban mobility, sustainable transport, strategic planning, people-centric approach
Procedia PDF Downloads 1342620 Oral Sex Practice among Men Who Have Sex with Men: A Cross-Sectional Study in Indonesian Urban Settings
Authors: I Putu Yuda Hananta, Inke Kusumastuti
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The latest Indonesian Biology and Behavior Surveillance (IBBS) conducted by Indonesian Ministry of Health reported a large proportion of men who have sex with men (MSM) engaging in oral sex in their recent sexual history. While it is considered as a pleasuring and safe, oral sex might facilitate the transmission of various sexually transmitted infection (STI) pathogens. This study was aimed to investigate the oral sex practice among MSM in Indonesian urban settings to help delineate demographic and behavior determinants of such practice. In 2014, 501 MSM in 8 clinic-based and outreach STI services were recruited in Jakarta, Yogyakarta and Denpasar, Indonesia. Respondents completed a self-administered questionnaire inquiring about their demographics and sexual history. Median age (interquartile range) of the respondents was 27 (24-30) years; most completed senior high school (54.3%), worked in informal jobs (57.9%), and single (60.9%); and 32.3% reported receiving money in exchange for sex. Oral sex was practiced by most respondents: insertive only (10.0%), receptive only (6.0%), and both (82.4%). A separate multivariable analysis was performed using logistic regression to identify the determinants for receptive and insertive oral sex. Factors associated with receptive oral sex were having more than 10 sex partner(s) in the preceding 6 months vs 1 partner, adjusted odds ratio (aOR) [95% CI]=3.40 [1.22-9.42], p=0.03; and history of receptive-insertive anal sex vs no history, aOR=4.37 [1.76-10.82], p=0.01. Factors associated with insertive oral sex were receiving money for sex vs. not receiving, aOR=2.98 [1.10-8.04], p=0.02; and history of receptive-insertive anal sex vs. no history, aOR=2.10 [0.51-8.74], p<0.001. Only a few respondents reported consistent condom use (11.6% and 12.0% for receptive and insertive oral sex, respectively). Our findings demonstrated that while oral sex is a common practice among MSM, the consistency of condom use in oral sex is very low. In addition, certain sex behavior (number of sex partners, sex work and history of anal sex) were associated with oral sex, and this might need to be addressed during health promotion efforts on STI prevention through oral-genital contact.Keywords: behavior, Indonesia, men who have sex with men, oral sex
Procedia PDF Downloads 2452619 Maternal Awareness of Sudden Infant Death Syndrome: A Jordanian Study
Authors: Nemeh Ahmad Al-Akour, Ibrahem Alfaouri
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Objective: To examine the level of maternal awareness of SIDS and its prevention amongst Jordanian mothers in the north of Jordan, as well as to determine their SIDS-related infant care practices. Design: A cross-sectional design. Setting: The study was conducted in maternal out-patients clinics of two teaching hospitals and three maternal and child health clinic in three major health care centers in Northern Jordan. Participants: A total of 356 mothers of infants attending the maternal and child health clinics were included in this study. Measurements and findings: A self-administered questionnaire was used for collecting data study. In this study, 64%of mothers didn’t hear about SIDS, while only 7% of mothers were able to identify factors risk-reducing recommendations. Avoidance of prone sleeping was the most frequently identified recommendation (5%). There were 67.7% of mothers who put their infant in a lateral position to sleep, 61% used soft mattress surface for their babies sleep and 25.8% who shared a bed with their babies. Employed mother, mothers of higher age, and mothers living within a nuclear family were the only factors associated with maternal awareness of SIDS. Friends were the highest a source of knowledge of SIDS for mothers (44.7%). Key conclusions: There was a low level of awareness of SIDS and its associated risk factor among the mothers in Jordan. The mothers' misconception about smoking and sleeping position for their infants requires further efforts. Implications for practice: To ensure raising awareness of infant care practice regarding SIDS, a national educational intervention on SIDS risk reduction strategies and recommendations is necessary for maintaining a low rate of SIDS in the population.Keywords: bed sharing, infant care, Jordan, sleep position, sudden infant death
Procedia PDF Downloads 3222618 Use of Waste Tire Rubber Alkali-Activated-Based Mortars in Repair of Concrete Structures
Authors: Mohammad Ebrahim Kianifar, Ehsan Ahmadi
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Reinforced concrete structures experience local defects such as cracks over their lifetime under various environmental loadings. Consequently, they are repaired by mortars to avoid detrimental effects such as corrosion of reinforcement, which in long-term may lead to strength loss of a member or collapse of structures. However, repaired structures may need multiple repairs due to changes in load distribution, and thus, lack of compatibility between mortar and substrate concrete. On the other hand, waste tire rubber alkali-activated (WTRAA)-based materials have very high potential to be used as repair mortars because of their ductility and flexibility, which may delay the failure of repair mortar and thus, provide sufficient compatibility. Hence, this work presents a pioneering study on suitability of WTRAA-based materials as mortars for the repair of concrete structures through an experimental program. To this end, WTRAA mortars with 15% aggregate replacement, alkali-activated (AA) mortars, and ordinary mortars are made to repair a number of concrete beams. The WTRAA mortars are composed of slag as base material, sodium hydroxide as an alkaline activator, and different gradations of waste tire rubber (fine and coarse gradations). Flexural tests are conducted on the concrete beams repaired by the ordinary, AA, and WTRAA mortars. It is found that, despite having lower compressive strength and modulus of elasticity, the WTRAA and AA mortars increase the flexural strength of the repaired beams, give compatible failures, and provide sufficient mortar-concrete interface bondings. The ordinary mortars, however, show incompatible failure modes. This study demonstrates the promising application of WTRAA mortars in the practical repairs of concrete structures.Keywords: alkali-activated mortars, concrete repair, mortar compatibility, flexural strength, waste tire rubber
Procedia PDF Downloads 1642617 Protein Feeding Pattern, Casein Feeding, or Milk-Soluble Protein Feeding did not Change the Evolution of Body Composition during a Short-Term Weight Loss Program
Authors: Solange Adechian, Michèle Balage, Didier Remond, Carole Migné, Annie Quignard-Boulangé, Agnès Marset-Baglieri, Sylvie Rousset, Yves Boirie, Claire Gaudichon, Dominique Dardevet, Laurent Mosoni
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Studies have shown that timing of protein intake, leucine content, and speed of digestion significantly affect postprandial protein utilization. Our aim was to determine if one can spare lean body mass during energy restriction by varying the quality and the timing of protein intake. Obese volunteers followed a 6-wk restricted energy diet. Four groups were compared: casein pulse, casein spread, milk-soluble protein (MSP, = whey) pulse, and MSP spread (n = 10-11 per group). In casein groups, caseins were the only protein source; it was MSP in MSP groups. Proteins were distributed in four meals per day in the proportion 8:80:4:8% in the pulse groups; it was 25:25:25:25% in the spread groups. We measured weight, body composition, nitrogen balance, 3-methylhistidine excretion, perception of hunger, plasma parameters, adipose tissue metabolism, and whole body protein metabolism. Volunteers lost 7.5 ± 0.4 kg of weight, 5.1 ± 0.2 kg of fat, and 2.2 ± 0.2 kg of lean mass, with no difference between groups. In adipose tissue, cell size and mRNA expression of various genes were reduced with no difference between groups. Hunger perception was also never different between groups. In the last week, due to a higher inhibition of protein degradation and despite a lower stimulation of protein synthesis, postprandial balance between whole body protein synthesis and degradation was better with caseins than with MSP. It seems likely that the positive effect of caseins on protein balance occurred only at the end of the experiment.Keywords: lean body mass, fat mass, casein, whey, protein metabolism
Procedia PDF Downloads 762616 Facilitating Written Biology Assessment in Large-Enrollment Courses Using Machine Learning
Authors: Luanna B. Prevost, Kelli Carter, Margaurete Romero, Kirsti Martinez
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Writing is an essential scientific practice, yet, in several countries, the increasing university science class-size limits the use of written assessments. Written assessments allow students to demonstrate their learning in their own words and permit the faculty to evaluate students’ understanding. However, the time and resources required to grade written assessments prohibit their use in large-enrollment science courses. This study examined the use of machine learning algorithms to automatically analyze student writing and provide timely feedback to the faculty about students' writing in biology. Written responses to questions about matter and energy transformation were collected from large-enrollment undergraduate introductory biology classrooms. Responses were analyzed using the LightSide text mining and classification software. Cohen’s Kappa was used to measure agreement between the LightSide models and human raters. Predictive models achieved agreement with human coding of 0.7 Cohen’s Kappa or greater. Models captured that when writing about matter-energy transformation at the ecosystem level, students focused on primarily on the concepts of heat loss, recycling of matter, and conservation of matter and energy. Models were also produced to capture writing about processes such as decomposition and biochemical cycling. The models created in this study can be used to provide automatic feedback about students understanding of these concepts to biology faculty who desire to use formative written assessments in larger enrollment biology classes, but do not have the time or personnel for manual grading.Keywords: machine learning, written assessment, biology education, text mining
Procedia PDF Downloads 2832615 Determination of the CCR5Δ32 Frequency in Emiratis and Tunisians and Screening of the CCR5 Gene for Novel Alleles in Emiratis
Authors: Sara A. Al-Jaberi, Salma Ben-Salem, Meriam Messedi, Fatma Ayadi, Lihadh Al-Gazali, Bassam R. Ali
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Background: The chemokine receptor components play crucial roles in the immune system and some of them serve as co-receptors for the HIV virus. Several studies have documented those variants in chemokine receptors are correlated with susceptibility and resistance to infection with HIV virus. For example, mutations in the chemokine receptor 5 gene (CCR5) resulting in loss-of-function (such as the homozygous CCR5Δ32) confer high degree of resistance to HIV infection. Heterozygotes for these variants exhibit slow progression to AIDS. The prevalence of CCR5 polymorphisms varies among ethnic and geographical groups. For example, the CCR5 Δ32 variant is present in 10–15% of north Europeans but is rarely encountered among Africans. This study aims to identify the prevalence of some CCR5 variants in two geographically distant Arab populations (namely Emiratis and Tunisians). Methodology: The prevalence of CCR5 gene variants including CCR5Δ32, FS299, C101X, A29S and C178R has been determined using PCR and direct DNA sequencing. A total of 403 unrelated healthy individuals (253 Emiratis and 150 Tunisians) were genotyped for the CCR5Δ32 variant using PCR amplification and gel electrophoresis. In addition, 200 Emiratis have been screened for other SNPs using Sanger DNA sequencing. Results: Among Emiratis, the allele frequency of the CCR5Δ32 variant has been found to be 0.002. In addition, two variants L55Q and A159 were found at a frequency of 0.002.Moreover, the prevalence of the CCR5Δ32 variant in Tunisians was estimated to be 0.013 which is relatively higher than its frequency in Emiratis but lower than Europeans. Conclusion: We conclude that the allele frequency of the most critical CCR5 polymorphism (Δ32) is extremely low among Emiratis compared to other Arabs and North Europeans. In addition, very low allele frequencies of other CCR5 polymorphisms have been detected among Emiratis.Keywords: chemokine receptors, CCR5Δ32, CCR5 polymorphisms, Emiratis, Arab populations
Procedia PDF Downloads 3832614 Clinical, Demographic and Molecular Characterization of Dengue, Chikungunya and Zika Viruses Causing Hemorrhagic Fever in North India
Authors: Suruchi Shukla, Shantanu Prakash, Amita Jain
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Introduction: Arboviral diseases are one of the most common causes of viral hemorrhagic fever (VHF). Of which, Dengue and Chikungunya pose a significant health problem in India. Arbovirus has a tendency to cross the territories and emerge in the new region. Considering the above issues, in the current study active surveillance was conducted among viral hemorrhagic fever (VHF) cases reported from Uttar Pradesh (UP), India. We studied the arboviral etiology of VHF; mainly Dengue, Chikungunya, and ZIKA. Methods: Clinical samples of 465 suspected VHF cases referred to tertiary care referral center of UP, India were enrolled in the study during a period from 15th May 2016 to 9th March 2018. Serum specimens were collected and analyzed for the presence of Dengue, Chikungunya, and ZIKA either by serology and/or by molecular assays. Results: Of all tested, 165 (35.4%) cases were positive for either Dengue or Chikungunya. Dengue (21.2%) was found to be the most prevalent, followed by Chikungunya, (6.6%). None of the cases tested positive for ZIKA virus. Serum samples of 35 (7.5%) cases were positive for both Dengue and Chikungunya. DEN-2 serotype was the most predominant serotype. Phylogenetic and sequence analysis of DEN-2 strains showed 100% clustering with the Cosmopolitan genotype strain. Bleeding from several sites, jaundice, abdominal pain, arthralgia, haemoconcentration, and thrombocytopenia were significantly higher in dengue hemorrhagic cases. However, the rash was significantly more common in Chikungunya patients. Most of the Dengue and Chikungunya positive cases (Age group 6-40 years) were seen in post monsoon season (September to November). Conclusion: Only one-third of total VHF cases are positive for either Dengue/Chikungunya or both. This necessitates the screening of other etiologies capable of causing hemorrhagic manifestations.Keywords: viral hemorrhagic fever, dengue, chikungunya, zika, India
Procedia PDF Downloads 1602613 Aggressive Behaviour and Its Association with Substance Use Disorder among Senior Secondary School Students in Ilesha, Nigeria
Authors: Famurewa Olumide Joseph, Akinsulore Adesanmi
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The current study investigated aggressive behaviour and its association with substance use disorder among senior secondary school students in Ilesha, Nigeria. Participants were three hundred and seventy-five (375) comprising (212) females and (163) males of senior secondary school students in Ilesa East and Ilesa West; who were randomly selected among the population of students from the schools. The mean age of the respondents was 14.61 years (S.D = 1.16), with 311 (82.9%) between 14 – 16 years. Female respondents were 212 (56.5%), while male respondents were 163 (43.5%). A cross sectional design was adopted. Three instruments were used for data collection. Buss Perry Aggression Questionnaire, Alcohol Use Disorder Identification Test (AUDIT) and Drug Abuse Screening Test (DAST). It was hypothesized that aggressive behaviour will be associated with substance use disorder among senior secondary school students in Ilesa East and Ilesa West. The result indicated that the overall prevalence of substance use disorder was 16.0%. Chi-Square test exploring the association between aggressive behaviour and substance use disorder shows that there is a significant association between aggressive behaviour and substance use disorder (χ2 =8.55, p =0.014). Results also showed that emotional problem (χ2 (2) =13.0; p = 0.001) was statistically significant while current medications intake (χ2 (2) =2.03; p =0.362) and overall wellbeing (χ2 (4) =2.49; p =0.646) were not statistically significant. There is an inverse association between prosocial behaviour and aggressive behaviour (r= -0.037, p>0.05). This indicates that as the level of prosocial behaviour increases, the level of aggressive behaviour among respondents decreases. However, alcohol use had no correlation with aggressive behaviour (r=0.070, p>0.05). Among the implications stated is that factors such as emotional symptoms, conduct problems, hyperactivity, peer problem and drug use contributed to the prevalence of aggressive behaviour among students. Suggestions for further studies were equally made.Keywords: aggressive behaviour, alcohol, prevalence, students, substance use disorder (SUD)
Procedia PDF Downloads 922612 Seroprevalence of Bovine Brucellosis and its Public Health Significance in Selected Sites of Central High Land of Ethiopia
Authors: Temesgen Kassa Getahun, Gezahegn Mamo, Beksisa Urge
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A cross-sectional study was conducted from December 2019 to May 2020 with the aim of determining the seroprevalence of brucellosis in dairy cows and their owners in the central highland of Oromia, Ethiopia. A total of 352 blood samples from dairy cattle, 149 from animal owners, and 17 from farm workers were collected and initially screened using the Rose Bengal Plate test and confirmed by the Complement Fixation test. Overall seroprevalence was 0.6% (95% CI: 0.0016–0.0209) in bovines and 1.2% (95% CI: 0.0032–0.0427) in humans. Market-based stock replacement (OR=16.55, p=0.002), breeding by artificial insemination (OR=7.58, p=0.05), and parturition pen (OR = 11.511, p=0.027) were found to be significantly associated with the seropositivity for Brucella infection in dairy cattle. Human housing (OR=1.8, p=0.002), contact with an aborted fetus (OR=21.19, p=0.017), drinking raw milk from non-aborted (OR=24.99, p=0.012), aborted (OR=5.72, p=0.019) and retained fetal membrane (OR=4.22, p=0.029) cows had a significant influence on human brucellosis. A structured interview question was administered to 284 respondents. Accordingly, most respondents had no knowledge of brucellosis (93.3%), and in contrast, 90% of them consumed raw milk. In conclusion, the present seroprevalence study revealed that brucellosis was low among dairy cattle and exposed individuals in the study areas. However, since there were no control strategies implemented in the study areas, there is a potential risk of transmission of brucellosis in dairy cattle and the exposed human population in the study areas. Implementation of a test and slaughter strategy with compensation to farmers is recommended, while in the case of human brucellosis, continuous social training and implementing one health approach framework must be applied.Keywords: abortion, bovine brucellosis, human brucellosis, risk factors, seroprevalence
Procedia PDF Downloads 1122611 Acanthopanax koreanum and Major Ingredient, Impressic Acid, Possess Matrix Metalloproteinase-13 Down-Regulating Capacity and Protect Cartilage Destruction
Authors: Hyun Lim, Dong Sook Min, Han Eul Yun, Kil Tae Kim, Ya Nan Sun, Young Ho Kim, Hyun Pyo Kim
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Matrix metalloproteinase (MMP)-13 has an important role for degrading cartilage materials under inflammatory conditions such as arthritis. Since the 70% ethanol extract of Acanthopanax koreanum inhibited MMP-13 expression in IL-1β-treated human chondrocyte cell line, SW1353, two major constituents including acanthoic acid and impressic acid were initially isolated from the same plant materials and their MMP-13 down-regulating capacity was examined. In IL-1β-treated SW1353 cells, acanthoic acid and impressic acid significantly and concentration-dependently inhibited MMP-13 expression at 10 – 100 μM and 0.5 – 10 μM, respectively. The potent one, impressic acid, was found to inhibit MMP-13 expression by blocking the phosphorylation of signal transducer and activator of transcription-1/-2 (STAT-1/-2) and activation of c-Jun and c-Fos among cellular signaling pathway involved, but did not affect the activation of mitogen-activated protein kinases (MAPKs) and nuclear transcription factor-κB (NF-κB). Further, impressic acid was also found to inhibit the expression of MMP-13 mRNA (47.7% inhibition at 10 μM), the glycosaminoglycan release (42.2% reduction at 10 μM) and proteoglycan loss in IL-1-treated rabbit cartilage explants culture. For a further study, 21 impressic acid derivatives were isolated from the same plant materials and their suppressive activities against MMP-13 expression were examined. Among the derivatives, 3α-hydroxy-lup-20(29)-en-23-oxo,28-oic acid, (20R)-3α-hydroxy-29-dimethoxylupan-23,28-dioic acid, acankoreoside F and acantrifoside A clearly down-regulated MMP-13 expression, but impressic acid being most potent. All these results suggest that impressic acid, 3α-hydroxy-lup-20(29)-en-23-oxo,28-oic acid, (20R)-3α-hydroxy-29-dimethoxylupan-23,28-dioic acid, acankoreoside F, acantrifoside A and A. koreanum may have a potential for therapeutic agents to prevent cartilage degradation possibly by inhibiting matrix protein degradation.Keywords: acanthoic acid, Acanthopanax koreanum, cartilage, impressic acid, matrix metalloproteinase
Procedia PDF Downloads 3672610 Trends in Domestic Terms of Trade of Agricultural Sector of Pakistan
Authors: Anwar Hussain, Muhammad Iqbal
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The changes in the prices of the agriculture commodities combined with changes in population and agriculture productivity affect farmers’ profitability and standard of living. This study intends to estimate various domestic terms of trade for agriculture sector and also to assess the volatility in the standard of living and profitability of farmers. The terms of trade has been estimated for Pakistan and its provinces using producer prices indices, consumer price indices, input prices indices and quantity indices using the data for the period 1990-91 to 2008-09. The domestic terms of trade of agriculture sector has been improved in terms of both approaches i.e. the ratio of producer prices indices to consumer prices indices and the real per capita income approach. However, the cross province estimates indicated that the terms of trade also improved for Khyber Pakhtunkhwa, Sindh and Punjab while Balochistan’s domestic terms of trade deteriorated drastically. In other words the standard of living of the farmers in Pakistan and its provinces except Balochistan improved. Using the input prices, the domestic terms of trade deteriorated for Pakistan as a whole and its provinces as well. This also explores that as a whole the profitability of the farmers reduced during the study period. The farmers pay more prices for inputs as compared to they receive for their produce. This further indicates that the poverty at the gross root level has been increased. Further, summing, the standard of living of the farmers improved but their profitability reduced, which indicates that the farmers do not completely rely on the farm income but also utilize some other sources of income for their livelihood. The study supports to give subsidies on farm inputs so as to improve the profitability of the farmers.Keywords: agricultural terms of trade, farmers’ profitability, farmers’ standard of living, consumer and producer price indices, quantity indices
Procedia PDF Downloads 4702609 Palliative Performance Scale Differences between Patients Referred by Specialized Cancer Center and General Hospitals to the Palliative Care Center in Kuwait
Authors: Khalid Al Saleh, Najlaa AlSayed
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Background: Palliative care is changing from just ‘end of life care’ to care delivered earlier in the disease course. Metanalysis showed that Palliative Performance Scale (PPS) is associated with increased length of survival. The Palliative Care Center (PCC) in Kuwait is the only stand-alone center in Eastern Mediterranean Region with a capacity of 92 beds. We compared clinical characteristics between patients referred from the Specialized Cancer Center and general hospitals in Kuwait to PCC. Method: A cross Sectional survey was conducted since the opening of PCC in January 2011 to June 2013. Patients’ data on demographics, type of the cancer, PPS score and referring hospital were collected and analyzed. Results: Total number of the patients was 142. Mean age was 61.05±14.79 years, 66 patients (47.1%) were males and 74 (52.9%) were females. The most common cancers in males were lung (n=18, 27.3%) followed by head and neck cancers (n=8, 12.1%) and brain tumors (n=7, 10.6%) while in females, the most common cancers were breast cancer (n=12, 16.7%) followed by ovarian cancer (n=10, 13.9%) and Cancer Colon (n=8, 11.1%). Patients with PPS score 30% were 27.9% (n=39), 40% in 40.7% (n=57), and 50% in 17.1% (n=24) respectively. Patients referred from the Specialized Cancer Center had significantly higher portion of patients with PPS score > 30% (73.4%, n=94), compared to patients coming from general hospitals (33.3%, n=4), P value= 0.007. Conclusion: There is significant difference in PPS scores between patients referred from the Specialized Cancer Center compared to patients referred from general hospitals. We encourage that all cancer patients should be treated in Specialized Cancer Centers and earlier involvement of Palliative Care Centers to achieve better survival. Training workshops are needed for health care professionals working in general hospitals to raise awareness about earlier referral of patients to palliative care services.Keywords: palliative care, kuwait, performance scale differences, pps score, specialized hospitals
Procedia PDF Downloads 3112608 Corrosion of Concrete Reinforcing Steel Bars Tested and Compared Between Various Protection Methods
Authors: P. van Tonder, U. Bagdadi, B. M. D. Lario, Z. Masina, T. R. Motshwari
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This paper analyses how concrete reinforcing steel bars corrode and how it can be minimised through the use of various protection methods against corrosion, such as metal-based paint, alloying, cathodic protection and electroplating. Samples of carbon steel bars were protected, using these four methods. Tests performed on the samples included durability, electrical resistivity and bond strength. Durability results indicated relatively low corrosion rates for alloying, cathodic protection, electroplating and metal-based paint. The resistivity results indicate all samples experienced a downward trend, despite erratic fluctuations in the data, indicating an inverse relationship between electrical resistivity and corrosion rate. The results indicated lowered bond strengths when the reinforced concrete was cured in seawater compared to being cured in normal water. It also showed that higher design compressive strengths lead to higher bond strengths which can be used to compensate for the loss of bond strength due to corrosion in a real-world application. In terms of implications, all protection methods have the potential to be effective at resisting corrosion in real-world applications, especially the alloying, cathodic protection and electroplating methods. The metal-based paint underperformed by comparison, most likely due to the nature of paint in general which can fade and chip away, revealing the steel samples and exposing them to corrosion. For alloying, stainless steel is the suggested material of choice, where Y-bars are highly recommended as smooth bars have a much-lowered bond strength. Cathodic protection performed the best of all in protecting the sample from corrosion, however, its real-world application would require significant evaluation into the feasibility of such a method.Keywords: protection methods, corrosion, concrete, reinforcing steel bars
Procedia PDF Downloads 1782607 Integrated Gas Turbine Performance Diagnostics and Condition Monitoring Using Adaptive GPA
Authors: Yi-Guang Li, Suresh Sampath
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Gas turbine performance degrades over time, and the degradation is greatly affected by environmental, ambient, and operating conditions. The engines may degrade slowly under favorable conditions and result in a waste of engine life if a scheduled maintenance scheme is followed. They may also degrade fast and fail before a scheduled overhaul if the conditions are unfavorable, resulting in serious secondary damage, loss of engine availability, and increased maintenance costs. To overcome these problems, gas turbine owners are gradually moving from scheduled maintenance to condition-based maintenance, where condition monitoring is one of the key supporting technologies. This paper presents an integrated adaptive GPA diagnostics and performance monitoring system developed at Cranfield University for gas turbine gas path condition monitoring. It has the capability to predict the performance degradation of major gas path components of gas turbine engines, such as compressors, combustors, and turbines, using gas path measurement data. It is also able to predict engine key performance parameters for condition monitoring, such as turbine entry temperature that cannot be directly measured. The developed technology has been implemented into digital twin computer Software, Pythia, to support the condition monitoring of gas turbine engines. The capabilities of the integrated GPA condition monitoring system are demonstrated in three test cases using a model gas turbine engine similar to the GE aero-derivative LM2500 engine widely used in power generation and marine propulsion. It shows that when the compressor of the model engine degrades, the Adaptive GPA is able to predict the degradation and the changing engine performance accurately using gas path measurements. Such a presented technology and software are generic, can be applied to different types of gas turbine engines, and provide crucial engine health and performance parameters to support condition monitoring and condition-based maintenance.Keywords: gas turbine, adaptive GPA, performance, diagnostics, condition monitoring
Procedia PDF Downloads 942606 Integrated Two Stage Processing of Biomass Conversion to Hydroxymethylfurfural Esters Using Ionic Liquid as Green Solvent and Catalyst: Synthesis of Mono Esters
Authors: Komal Kumar, Sreedevi Upadhyayula
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In this study, a two-stage process was established for the synthesis of HMF esters using ionic liquid acid catalyst. Ionic liquid catalyst with different strength of the Bronsted acidity was prepared in the laboratory and characterized using 1H NMR, FT-IR, and 13C NMR spectroscopy. Solid acid catalyst from the ionic liquid catalyst was prepared using the immobilization method. The acidity of the synthesized acid catalyst was measured using Hammett function and titration method. Catalytic performance was evaluated for the biomass conversion to 5-hydroxymethylfurfural (5-HMF) and levulinic acid (LA) in methyl isobutyl ketone (MIBK)-water biphasic system. A good yield of 5-HMF and LA was found at the different composition of MIBK: Water. In the case of MIBK: Water ratio 10:1, good yield of 5-HMF was observed at ambient temperature 150˚C. Upgrading of 5-HMF into monoesters from the reaction of 5-HMF and reactants using biomass-derived monoacid were performed. Ionic liquid catalyst with -SO₃H functional group was found to be best efficient in comparative of a solid acid catalyst for the esterification reaction and biomass conversion. A good yield of 5-HMF esters with high 5-HMF conversion was found to be at 105˚C using the best active catalyst. In this process, process A was the hydrothermal conversion of cellulose and monomer into 5-HMF and LA using acid catalyst. And the process B was the esterification followed by using similar acid catalyst. All monoesters of 5-HMF synthesized here can be used in chemical, cross linker for adhesive or coatings and pharmaceutical industry. A theoretical density functional theory (DFT) study for the optimization of the ionic liquid structure was performed using the Gaussian 09 program to find out the minimum energy configuration of ionic liquid catalyst.Keywords: biomass conversion, 5-HMF, Ionic liquid, HMF ester
Procedia PDF Downloads 256