Search results for: Information Systems Research
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 36302

Search results for: Information Systems Research

5642 Assessing the Lifestyle Factors, Nutritional and Socioeconomic Status Associated with Peptic Ulcer Disease: A Cross-Sectional Study among Patients at the Tema General Hospital of Ghana

Authors: Marina Aferiba Tandoh, Elsie Odei

Abstract:

Peptic Ulcer Disease (PUD) is amongst the commonest gastrointestinal problems that require emergency treatment in order to preserve life. The prevalence of PUD is increasing within the Ghanaian population, deepening the need to identify factors that are associated with its occurrence. This cross-sectional study assessed the nutritional status, socioeconomic and lifestyle factors associated with PUD among patients attending the Out-Patient Department of the Tema General Hospital of Ghana. A food frequency questionnaire and a three-day, 24-hour recall were used to assess the dietary intakes of study participants. A standardized questionnaire was used to obtain information on the participants’ socio-demographic characteristics, lifestyle as well as medical history. The data was analyzed using SPSS version 22. The mean age of study participants was 32.8±15.41years. Females were significantly higher (61.4%) than males (38.6%) (p < 0.001). All participants had received some form of education, with tertiary education being the highest (52.6%). The majority of them managed their condition with medications only (86%), while 10.5% managed it with a combination of medications and diet. The rest were either by dietary counseling only (1.8%), or surgery only (1.8%). or herbal medicines (29.3%), which were made from home (7.2%) or bought from a medical store (10.8%). Most of the participants experienced a recurrence of the disease (42.1%). For those who had ever experienced recurrences of the disease, it happened when they ate acidic foods (1.8%), ate bigger portions (1.8%), starved themselves (1.8%), or were stressed (1.8%). Others also had triggers when they took certain medications (1.8%) or ate too much pepper (1.8%). About 49% of the participants were either overweight or obese with a recurrence of PUD (p>0.05). Obese patients had the highest rate of PUD recurrences (41%). Drinking alcohol was significantly associated with the recurrence of PUD (χ2= 5.243, p=0.026). Other lifestyles, such as weed smoking, fasting, and use of herbal medicine and NSAIDs did not have any significant association with the disease recurrence. There was no significant correlation between the various dietary patterns and anthropometric parameters except dietary pattern one (salty snacks, regular soft drinks, milk, sweetened yogurt, ice cream, and cooked vegetables), which had a positive correlation with weight (p=0.002) and BMI (p=0.038). PUD patients should target weight reduction actions and reduce alcohol intake as measures to control the recurrence of the disease. Nutrition Education among this population must be promoted to minimize the recurrence of PUD.

Keywords: Dietary patterns, lifestyle factors, nutritional status, peptic ulcer disease

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5641 Judicial Review of Indonesia's Position as the First Archipelagic State to implement the Traffic Separation Scheme to Establish Maritime Safety and Security

Authors: Rosmini Yanti, Safira Aviolita, Marsetio

Abstract:

Indonesia has several straits that are very important as a shipping lane, including the Sunda Strait and the Lombok Strait, which are the part of the Indonesian Archipelagic Sea Lane (IASL). An increase in traffic on the Marine Archipelago makes the task of monitoring sea routes increasingly difficult. Indonesia has proposed the establishment of a Traffic Separation Scheme (TSS) in the Sunda Strait and the Lombok Strait and the country now has the right to be able to conceptualize the TSS as well as the obligation to regulate it. Indonesia has the right to maintain national safety and sovereignty. In setting the TSS, Indonesia needs to issue national regulations that are in accordance with international law and the general provisions of the IMO (International Maritime Organization) can then be used as guidelines for maritime safety and security in the Sunda Strait and the Lombok Strait. The research method used is a qualitative method with the concept of linguistic and visual data collection. The source of the data is the analysis of documents and regulations. The results show that the determination of TSS was justified by International Law, in accordance with article 22, article 41, and article 53 of the United Nations Convention on the Law of the Sea (UNCLOS) 1982. The determination of TSS by the Indonesian government would be in accordance with COLREG (International Convention on Preventing Collisions at Sea) 10, which has been designed to follow IASL. Thus, TSS can provide a function as a safety and monitoring medium to minimize ship accidents or collisions, including the warship and aircraft of other countries that cross the IASL.

Keywords: archipelago state, maritime law, maritime security, traffic separation scheme

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5640 Physical Activity Patterns during Inpatient Rehabilitation in Patients with Recent Brain Injury

Authors: Nikita Pasricha, Karen Smith, Simone Marshall, Vincent DePaul, Jessica Trier

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Understanding that physical activity in rehabilitation programs shapes outcomes in acquired brain injury (ABI) populations is not a new concept. However, there is a void in understanding the physical activity patterns of inpatients in ABI rehabilitation, the trajectory of physical activity recovery, and factors that contribute to the recovery of physical activity over the initial months post-ABI. The purpose of this study was to determine if physical activity patterns vary in people with recent ABI in inpatient rehabilitation. The study also investigated differences in physical activity patterns in ABI patients compared to age-related healthy participants. Results revealed that ABI patients spent approximately 6.7 times longer per day in sedentary postures than in active positions. In comparison, the control group spent only 2.8 times longer in sedentary postures compared to active positions. Patients with ABI took significantly fewer steps than age-matched health control participants. Within the ABI population, patients took 0.78 times fewer steps on weekends compared to weekdays. Participants with greater mobility limitations had a greater difference in WD to WE steps taken. Potential reasons could be from no structured weekend rehabilitation programs, lower availability of staff, or varying schedules. Given that the rehabilitation program is only structured on weekdays, further research to investigate the benefits of structured physical activities like group walking programs on weekends for ABI patients in inpatient rehabilitation programs is warranted.

Keywords: brain, ABI, TBI, rehabilitation

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5639 Optimizing Emergency Rescue Center Layouts: A Backpropagation Neural Networks-Genetic Algorithms Method

Authors: Xiyang Li, Qi Yu, Lun Zhang

Abstract:

In the face of natural disasters and other emergency situations, determining the optimal location of rescue centers is crucial for improving rescue efficiency and minimizing impact on affected populations. This paper proposes a method that integrates genetic algorithms (GA) and backpropagation neural networks (BPNN) to address the site selection optimization problem for emergency rescue centers. We utilize BPNN to accurately estimate the cost of delivering supplies from rescue centers to each temporary camp. Moreover, a genetic algorithm with a special partially matched crossover (PMX) strategy is employed to ensure that the number of temporary camps assigned to each rescue center adheres to predetermined limits. Using the population distribution data during the 2022 epidemic in Jiading District, Shanghai, as an experimental case, this paper verifies the effectiveness of the proposed method. The experimental results demonstrate that the BPNN-GA method proposed in this study outperforms existing algorithms in terms of computational efficiency and optimization performance. Especially considering the requirements for computational resources and response time in emergency situations, the proposed method shows its ability to achieve rapid convergence and optimal performance in the early and mid-stages. Future research could explore incorporating more real-world conditions and variables into the model to further improve its accuracy and applicability.

Keywords: emergency rescue centers, genetic algorithms, back-propagation neural networks, site selection optimization

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5638 Understanding Indigenous Perspectives and Critical Knowledge in International Law

Authors: Radhika Jagtap

Abstract:

Contemporary scholarship in international legal theory is investigating new avenues of providing alternatives to dominant concepts. Indigenous peoples’ philosophies and perspectives developed through them provide a fertile ground to explore similar alternative ideas. This review paper evaluates the theorized accounts of indigenous scholarships which have contributed towards a rich body of knowledge generating alternative visions on dominant notions of ‘post coloniality’, ‘resistance’ and ‘globalization’. Further, it shall assess the relevance of such a project in shaping contemporary international legal thought. Traditional or classical international law has been opined to be highly influenced by the colonial and imperialist history which also left a mark on the way dominant discourses of resistance and globalization are read in mainstream international law. The paper shall first define what do we mean by indigenous philosophy and what kind of indigeneity is that inclusive of. Second, the paper defines the dominant discourse and then counters the same with the alternative indigenous perspective in the case of each concept that is in question. Finally, the paper shall conclude with certain theoretical findings – that the post coloniality, from indigenous perspective, lead to the further marginalization of indigeneity, especially in the third world; that human rights as the sole means of representing resistance in international law ends up making it a very state-centric discipline and last, that globalization from an indigenous, marginalised perspective is not as celebrated as it is in mainstream international law. Major scholarly works that shall be central to the discussion are those of Linda Tuiwahi Smith, Ella Shohat and David Harvey. The nature of the research shall be inductive and involve mostly theoretical review of scholarly works.

Keywords: indigenous, post colonial, globalization, perspectives

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5637 Virtual Simulation as a Teaching Method for Community Health Nursing: An Investigation of Student Performance

Authors: Omar Mayyas

Abstract:

Clinical decision-making (CDM) is essential to community health nursing (CHN) education. For this reason, nursing educators are responsible for developing these skills among nursing students because nursing students are exposed to highly critical conditions after graduation. However, due to limited exposure to real-world situations, many nursing students need help developing clinical decision-making skills in this area. Therefore, the impact of Virtual Simulation (VS) on community health nursing students' clinical decision-making in nursing education has to be investigated. This study aims to examine the difference in CDM ability among CHN students who received traditional education compared to those who received VS classes, to identify the factors that may influence CDM ability differences between CHN students who received a traditional education and VS classes, and to provide recommendations for educational programs that can enhance the CDM ability of CHN students and improve the quality of care provided in community settings. A mixed-method study will conduct. A randomized controlled trial will compare the CDM ability of CHN students who received 1hr traditional class with another group who received 1hr VS scenario about diabetic patient nursing care. Sixty-four students in each group will randomly select to be exposed to the intervention from undergraduate nursing students who completed the CHN course at York University. The participants will receive the same Clinical Decision Making in Nursing Scale (CDMNS) questionnaire. The study intervention will follow the Medical Research Council (MRC) approach. SPSS and content analysis will use for data analysis.

Keywords: clinical decision-making, virtual simulation, community health nursing students, community health nursing education

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5636 Green Hospitality Industry: An Experience Study with Game Theory in China

Authors: Min Wei

Abstract:

The green hotel provides the products/services consistent with the full utilization of resources, protecting the ecological environment conducive to customers’ requirements and health. In order to better develop the green hospitality industry, this paper applies the game theory to analyze the intrinsic relationship and balanced interests among the stakeholders including government, hotels, and tourists during green hospitality development. Based on the hypothesis in game theory, this paper tries to construct a linkage mechanism in stakeholders, by which a theoretical basis for the interests’ balance can be realized. By using game theory and constructing a game model including tourists, hotels and government, this paper analyzes the relationship of the various stakeholders involved in the green hospitality development, and subsequently proposes the development model of green hospitality industry. On the one hand, this paper applies game theory to construct a green hotel development model and provides a theoretical basis for the interest balance of stakeholders based on theoretical perspective. On the other hand, the current development of green hospitality industry is still in initial phase, and the outcome of this research tries to guide tourists to form a green awareness and to establish the concept of green consumption for hotel development, so that green hotel products/services are provided. In addition, this paper provides a basis for decision making in the relevant government departments so that the interests of all stakeholders are promoted and cooperative game between stakeholders is established, for which the sustainable development of green hotels is achieved. The findings indicate that the process of achieving green hospitality industry development is to maximize the whole interests of stakeholders.

Keywords: green hospitality, game theory, stakeholders, development model

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5635 Conflict, Confusion or Compromise: Violence against Women, A Case Study of Pakistan

Authors: Farhat Jabeen, Syed Asfaq Hussain Bukhari

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In the wake of the contemporary period the basic objective of the research paper points out that socio-cultural scenario of Pakistan reveals that gender-based violence is deep rooted in the society irrespective of language and ethnicity. This paper would reconnaissance the possibility reforms in Pakistan for diminishing of violence. Women are not given their due role, rights, and respect. Furthermore, they are treated as chattels. This presentation will cover the socio-customary practices in the context of discrimination, stigmatization, and violence against women. This paper envisages justice in a broader sense of recognition of rights for women, and masculine structure of society, socio-customary practices and discrimination against women are a very serious concern which needs to be understood as a multidimensional problem. The paper will specially focus on understanding the existing obstacles of women in Pakistan in the constitutional scenario. Women stumble across discrimination and human rights manipulations, voluptuous violation and manipulation including domestic viciousness and are disadvantaged by laws, strategies, and programming that do not take their concerns into considerations. This presentation examines the role of honour killings among Pakistani community. This affects their self-assurance and capability to elevation integrity campaign where gender inequalities and discrimination in social, legal domain are to be put right. This paper brings to light the range of practices, laws and legal justice regarding the status of women and also covers attitude towards compensations for murders/killings, domestic violence, rape, adultery, social behavior and recourse to justice.

Keywords: discrimination, cultural, women, violence

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5634 In Vitro Antioxidant and Cytotoxic Activities Against Human Oral Cancer and Human Laryngeal Cancer of Limonia acidissima L. Bark Extracts

Authors: Kriyapa lairungruang, Arunporn Itharat

Abstract:

Limonia acidissima L. (LA) (Common name: wood apple, Thai name: ma-khwit) is a medicinal plant which has long been used in Thai traditional medicine. Its bark is used for treatment of diarrhea, abscess, wound healing and inflammation and it is also used in oral cancer. Thus, this research aimed to investigate antioxidant and cytotoxic activities of the LA bark extracts produced by various extraction methods. Different extraction procedures were used to extract LA bark for biological activity testing: boiling in water, maceration with 95% ethanol, maceration with 50% ethanol and water boiling of each the 95% and the 50% ethanolic residues. All extracts were tested for antioxidant activity using DPPH radical scavenging assay, cytotoxic activity against human laryngeal epidermoid carcinoma (HEp-2) cells and human oral epidermoid carcinoma (KB) cells using sulforhodamine B (SRB) assay. The results found that the 95% ethanolic extract of LA bark showed the highest antioxidant activity with EC50 values of 29.76±1.88 µg/ml. For cytotoxic activity, the 50% ethanolic extract showed the best cytotoxic activity against HEp-2 and KB cells with IC50 values of 9.55±1.68 and 18.90±0.86 µg/ml, respectively. This study demonstrated that the 95% ethanolic extract of LA bark showed moderate antioxidant activity and the 50% ethanolic extract provided potent cytotoxic activity against HEp-2 and KB cells. These results confirm the traditional use of LA for the treatment of oral cancer and laryngeal cancer, and also support its ongoing use.

Keywords: antioxidant activity, cytotoxic activity, Laryngeal epidermoid carcinoma, Limonia acidissima L., oral epidermoid carcinoma

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5633 Early Depression Detection for Young Adults with a Psychiatric and AI Interdisciplinary Multimodal Framework

Authors: Raymond Xu, Ashley Hua, Andrew Wang, Yuru Lin

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During COVID-19, the depression rate has increased dramatically. Young adults are most vulnerable to the mental health effects of the pandemic. Lower-income families have a higher ratio to be diagnosed with depression than the general population, but less access to clinics. This research aims to achieve early depression detection at low cost, large scale, and high accuracy with an interdisciplinary approach by incorporating clinical practices defined by American Psychiatric Association (APA) as well as multimodal AI framework. The proposed approach detected the nine depression symptoms with Natural Language Processing sentiment analysis and a symptom-based Lexicon uniquely designed for young adults. The experiments were conducted on the multimedia survey results from adolescents and young adults and unbiased Twitter communications. The result was further aggregated with the facial emotional cues analyzed by the Convolutional Neural Network on the multimedia survey videos. Five experiments each conducted on 10k data entries reached consistent results with an average accuracy of 88.31%, higher than the existing natural language analysis models. This approach can reach 300+ million daily active Twitter users and is highly accessible by low-income populations to promote early depression detection to raise awareness in adolescents and young adults and reveal complementary cues to assist clinical depression diagnosis.

Keywords: artificial intelligence, COVID-19, depression detection, psychiatric disorder

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5632 The Inhibition of Sexual Pleasure and Its Associations with Cultural Messages

Authors: Fabiola Trejo Perez, Rolando Diaz Loving

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Sexual pleasure consists of the positively valued feelings induced by sexual stimuli, but it is also weighed down by pop-psychological baggage, and subjected to cross-cultural and cross-historical variation. Social and individual interpretations of what can or can’t be considered as pleasurable are intertwined with culture’s predominant values, norms and beliefs. For each culture, sexual norms work as a guide to be followed in order to model socially accepted behaviors. Therefore, cultural messages regarding sexuality are usually directed to restrict men and women from enjoyment, sexual satisfaction and specifically orgasm. Given that sexual pleasure hasn’t been recognized as an accepted topic of open discussion, particularly for women, people have to eventually complement their knowledge using their own experience filling in the blanks from what little has been said. Thus, this research aims to identify which are the particular social messages associated with the easing or inhibition of sexual pleasure. Three hundred Mexican men and women ages 25 to 35 years old answered a self-report survey composed by the Inventory of facilitators and inhibitors of sexual pleasure and the Sexual premises questionnaire via pencil-paper and online. Results show a high endorsement to double standard messages associated with higher levels of sexual pleasure inhibitors like feeling pressured to have sexual activity, guilt and inability to reach orgasm, in contrast with people who endorse more permissive norms and beliefs, feeling connected to their sexual partners and confident with themselves. These results illustrate that the shaping of sexuality, from experience to society, is comprised of an important relationship between culture and sexual pleasure.

Keywords: culture, sexual double standard, sexual norms and beliefs, sexual pleasure

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5631 Variability in Contraception Choices and Abortion Rates among Female Garment Factory Workers in Urban and Rural Cambodia

Authors: Olalekan Olaluwoye, Joanne Williams, Elizabeth Hoban

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Background: Modern contraceptives are effective in preventing unwanted pregnancies and therefore the potential to reduce abortion rates. There is a need for information about how rates of contraceptive use and abortion vary across Cambodia and the relationship between the prevalence of modern contraception use and abortion rates. This study compares the use of contraception and abortion among female garment factory workers in rural and urban areas of Cambodia. Method: Cross-sectional surveys were conducted with 1701 women working in eleven garment factories in rural and urban areas of Cambodia. Sexual and reproductive health data were collected using Audio-Assisted Survey Interviews and analysed using STATA 14 software. Findings: Over 70% of the respondents were less than 30 years of age across both rural and urban settings and over 50% have only primary education, thus the study population was largely young women with limited education. A significantly higher proportion of the rural women earned over $200 in the previous month compared with their urban counterparts. The majority of the urban women (51.5%) were married, while single women (46.9%) made up the largest group working in the rural factories. A significantly larger proportion of women in the rural areas (83.9%) were sexually active compared to the urban women (50.9%). More women from the rural areas (41.4%) had been pregnant at some time compared with the urban population (37.7%). The use of any contraceptive method among sexually active women was significantly higher in the rural areas (80.1%) compared to the urban areas (65.7%) with p-value=0.000. However, among those women who used contraception, the prevalence of modern contraception use was slightly higher in the urban population (68.8% urban, 63.4% rural, p-value=0.1). For women who had a history of pregnancy the abortion prevalence was higher among rural women (43.8%) compared to their urban counterparts (37.7%). Regression analysis showed that after adjustment for the demographic variables (age, relationship status, income, education) only age and relationship status had a significant influence on the use of modern contraception.Single females who were sexually active and older women, who had potentially completed their families, were more likely to choose modern contraception. Conclusion: Although overall the use of contraception was higher among rural women, the use of modern contraception was higher among urban women.This finding may partly explain the higher rates of abortion among women in the rural areas as traditional contraception methods have higher failure rates and are more likely to result in an unplanned pregnancy.Despite the regional variation, the high rates of abortion across the country suggest there is a need for improve education on family planning among female garment factory workers in Cambodia.

Keywords: abortion, Cambodia, contraception, garment factory

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5630 Observations on the Eastern Red Sea Elasmobranchs: Data on Their Distribution and Ecology

Authors: Frappi Sofia, Nicolas Pilcher, Sander DenHaring, Royale Hardenstine, Luis Silva, Collin Williams, Mattie Rodrigue, Vincent Pieriborne, Mohammed Qurban, Carlos M. Duarte

Abstract:

Nowadays, elasmobranch populations are disappearing at a dangerous rate, mainly due to overexploitation, extensive fisheries, as well as climate change. The decline of these species can trigger a cascade effect, which may eventually lead to detrimental impacts on local ecosystems. The Elasmobranch in the Red Sea is facing one of the highest risks of extinction, mainly due to unregulated fisheries activities. Thus, it is of paramount importance to assess their current distribution and unveil their environmental preferences in order to improve conservation measures. Important data have been collected throughout the whole red Sea during the Red Sea Decade Expedition (RSDE) to achieve this goal. Elasmobranch sightings were gathered through the use of submarines, remotely operated underwater vehicles (ROV), scuba diving operations, and helicopter surveys. Over a period of 5 months, we collected 891 sightings, 52 with submarines, 138 with the ROV, 67 with the scuba diving teams, and 634 from helicopters. In total, we observed 657 and 234 individuals from the superorder Batoidea and Selachimorpha, respectively. The most common shark encountered was Iago omanensis, a deep-water shark of the order Carcharhiniformes. To each sighting, data on temperature, salinity density, and dissolved oxygen were integrated to reveal favorable conditions for each species. Additionally, an extensive literature review on elasmobranch research in the Eastern Red Sea has been carried out in order to obtain more data on local populations and to be able to highlight patterns of their distribution.

Keywords: distribution, elasmobranchs, habitat, rays, red sea, sharks

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5629 Assessing Socio-economic Impacts of Arsenic and Iron Contamination in Groundwater: Feasibility of Rainwater Harvesting in Amdanga Block, North 24 Parganas, West Bengal, India

Authors: Rajkumar Ghosh

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The present study focuses on conducting a socio-economic assessment of groundwater contamination by arsenic and iron and explores the feasibility of rainwater harvesting (RWH) as an alternative water source in the Amdanga Block of North 24 Parganas, West Bengal, India. The region is plagued by severe groundwater contamination, primarily due to excessive concentrations of arsenic and iron, which pose significant health risks to the local population. The study utilizes a mixed-methods approach, combining quantitative analysis of water samples collected from different locations within the Amdanga Block and socio-economic surveys conducted among the affected communities. The results reveal alarmingly high levels of arsenic and iron contamination in the groundwater, surpassing the World Health Organization (WHO) and Indian government's permissible limits. This contamination significantly impacts the health and well-being of the local population, leading to a range of health issues such as skin The water samples are analyzed for arsenic and iron levels, while the surveys gather data on water usage patterns, health conditions, and socio-economic factors. lesions, respiratory disorders, and gastrointestinal problems. Furthermore, the socio-economic assessment highlights the vulnerability of the affected communities due to limited access to safe drinking water. The findings reveal the adverse socio-economic implications, including increased medical expenditures, reduced productivity, and compromised educational opportunities. To address these challenges, the study explores the feasibility of rainwater harvesting as an alternative source of clean water. RWH systems have the potential to mitigate groundwater contamination by providing a sustainable and independent water supply. The assessment includes evaluating the rainwater availability, analyzing the infrastructure requirements, and estimating the potential benefits and challenges associated with RWH implementation in the study area. The findings of this study contribute to a comprehensive understanding of the socio-economic impact of groundwater contamination by arsenic and iron, emphasizing the urgency to address this critical issue in the Amdanga Block. The feasibility assessment of rainwater harvesting serves as a practical solution to ensure a safe and sustainable water supply, reducing the dependency on contaminated groundwater sources. The study's results can inform policymakers, researchers, and local stakeholders in implementing effective mitigation measures and promoting the adoption of rainwater harvesting as a viable alternative in similar arsenic and iron-contaminated regions.

Keywords: contamination, rainwater harvesting, groundwater, sustainable water supply

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5628 Association of Human Immunodeficiency Virus with Incident Autoimmune Hemolytic Anemia: A Population-Based Cohort Study in Taiwan

Authors: Yung-Feng Yen, I-an Jen, Yi-Ming Arthur Chen

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The molecular mimicry between human immunodeficiency virus (HIV) protein and red blood cell (RBC) antigens could induce the production of anti-RBC autoantibodies. However, the association between HIV infection and subsequent development of autoimmune hemolytic anemia (AIHA) remains unclear. This nationwide population-based cohort study aimed to determine the association between incident AIHA and HIV in Taiwan. From 2000–2012, we identified adult people living with HIV/AIDS (PLWHA) from the Taiwan centers for disease control HIV Surveillance System. HIV-infected individuals were defined by positive HIV-1 western blot. Age- and sex-matched controls without HIV infection were selected from the Taiwan National Health Insurance Research Database for comparison. All patients were followed until Dec. 31, 2012, and observed for occurrence of AIHA. Of 171,468 subjects (19,052 PLWHA, 152,416 controls), 30 (0.02%) had incident AIHA during a mean follow-up of 5.45 years, including 23 (0.12%) PLWHA and 7 (0.01%) controls. After adjusting for potential confounders, HIV infection was found to be an independent risk factor of incident AIHA (adjusted hazard ratio [AHR], 20.9; 95% confidence interval [CI], 8.34-52.3). Moreover, PLWHA receiving HAART were more likely to develop AIHA than those not receiving HAART (AHR, 10.8; 95% CI, 2.90-40.1). Additionally, the risk of AIHA was significantly increased in those taking efavirenz (AHR, 3.15; 95% CI, 1.18-8.43) or atazanavir (AHR, 6.58; 95% CI, 1.88-22.9) component of the HAART. In conclusion, HIV infection is an independent risk factor for incident AIHA. Clinicians need to be aware of the higher risk of AIHA in PLWHA.

Keywords: autoimmune disease , hemolytic anemia, HIV, highly active antiretroviral treatment

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5627 Moral Identity and Moral Attentiveness as Predictors of Ethical Leadership in Financial Sector

Authors: Pilar Gamarra Gamarra, Michele Girotto

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In the expanding field of leaders’ ethical behavior research, little attention has been paid to the association between finance leaders’ ethical traits (beyond personality) and ethical leadership, and more importantly, how these ethical characteristics can be predictors of ethical behavior at the leadership level in the financial sector. In this study, we tested a theoretical model based on uponsocial cognitive theory (Bandura, 1986) and the cognitive-developmental model (Piaget, 1932) to examine leaders’ moral identity and moral attentiveness as antecedents of ethical leadership. After the 2008 economic crisis, the marketplace has awakened to the potential dangers of unethical behavior. The unethical behavior of the leaders of the financial sector was identified as guilty of this economic catastrophe. For that reason, it seems increasingly prudent for organizations to have leaders who are cognitively inclined toward ethical behavior. This evidence suggests that moral attentiveness and moral identity is perhaps one way of identifying those kinds of leaders. For leaders who are morally attentive and have a high moral identity, themes of ethics interventions are consistent with their way of seeing the word. As a result, these leaders could become critical components of change in organizations and could provide the energy and skills necessary for these efforts to be successful. Ethical behavior of leader from the financial sector and marketing sectors must be joined to manage the change. In this study, a leader’s moral identity, leader’s moral attentiveness, and self-importance of Ethical Leadership are measured for financial and marketing leaders to be compared to determine the relationship between the three variables in each sector. Other conclusion related to gender, educational level or generation are obtained.

Keywords: ethical leadership, moral identity, moral attentiveness, financial leaders, marketing leaders, ethical behavior

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5626 Achieving Quality of Life and Sustainability in Mexican Cities, the Case of the Housing Complex “Villa del Campo”, Tijuana, Mexico

Authors: María de los Ángeles Zárate López, Juan Antonio Pitones Rubio

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Quality of life and sustainability in cities are among the most important challenges faced by designers, city planners and urban managers. The Mexican city of Tijuana has a particular dynamic in its demographics which has been accelerated by its border city condition, putting to the test the ability from authorities to provide the population with the necessary services to aspire for a deserving quality of life. In the recent story of Tijuana, we found that the housing policy and the solutions presented by private housing developers have not met the best living conditions for end users by far, thereby adding issues to current social problems which impact the whole metropolitan area, including damage to the natural environment. Therefore this research presents the case study about the situation of a suburban housing development near Tijuana named “Villa del Campo” and exposes the problems of this specific project (originally labelled as a “sustainable” proposal) demonstrating that, once built, the place does not reflect the quality of life that it promised as a project. Currently, this housing development has a number of problematic issues such as the faulty operating conditions of public utilities and serious cases of crime inside the neighborhood. There is no intention to only expose the negative side of this case study, but to explore some alternatives which could help solving the most serious problems at the place, considering possible architectural and landscape interventions within the housing complex to help achieve the optimal conditions of livability and sustainability required by their inhabitants.

Keywords: suburban, housing, quality of life, sustainability, Tijuana, demographics

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5625 Pre and Post IFRS Loss Avoidance in France and the United Kingdom

Authors: T. Miková

Abstract:

This paper analyzes the effect of a single uniform accounting rule on reporting quality by investigating the influence of IFRS on earnings management. This paper examines whether earnings management is reduced after IFRS adoption through the use of “loss avoidance thresholds”, a method that has been verified in earlier studies. This paper concentrates on two European countries: one that represents the continental code law tradition with weak protection of investors (France) and one that represents the Anglo-American common law tradition, which typically implies a strong enforcement system (the United Kingdom). The research investigates a sample of 526 companies (6822 firm-year observations) during the years 2000 – 2013. The results are different for the two jurisdictions. This study demonstrates that a single set of accounting standards contributes to better reporting quality and reduces the pervasiveness of earnings management in France. In contrast, there is no evidence that a reduction in earnings management followed the implementation of IFRS in the United Kingdom. Due to the fact that IFRS benefit France but not the United Kingdom, other political and economic factors, such legal system or capital market strength, must play a significant role in influencing the comparability and transparency cross-border companies’ financial statements. Overall, the result suggests that IFRS moderately contribute to the accounting quality of reported financial statements and bring benefit for stakeholders, though the role played by other economic factors cannot be discounted.

Keywords: accounting standards, earnings management, international financial reporting standards, loss avoidance, reporting quality

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5624 Perinatal and Postnatal Counseling as Determinants of Early Newborn Sepsis in Rural Bangladesh

Authors: Sajia Islam, T. Tahsina, S. Raihana, M. M. Rahman, Q. S. Rahman, T. M. Huda, S. E. Arifeen, M. J. Dibley

Abstract:

Early neonatal sepsis accounts for more than two-thirds of all deaths in the first year of life. This study assessed the counseling during antenatal, perinatal, post natal periods and its association with possible sepsis in rural Bangladesh. Method: Data were collected from a large community-based trial in Bangladesh where pregnant women were enrolled from 2013-2015 covering 29,497 newborns. Sepsis was defined using neonatal danger signs reported by 'The Young-Infants Clinical Science Study Group. 'Result: Signs of sepsis was found among 15% of the neonates. Neonatal sepsis was higher among those who did not receive advice on TT vaccinations (15.4% vs. 11%, p < 0.05) and danger signs (14.8% vs. 12.8%, p < 0.05) during pregnancy. Advice on delivering in well-lit place was significantly associated with lower incidence of sepsis (12.7% vs. 14.8% p < 0.05). Sepsis was lower among neonates whose mothers were counseled on immediate newborn care for bathing after 3 days of delivery (13.4% vs. 15.2% p=0), breastfeeding within 1hr of birth (13.82 % vs. 15.28% p=0), apply nothing on the cord (11.54 vs. 15.06 p=0), immediate drying of child (12.62% vs. 14.89%, p=0). Neonatal sepsis was lower among children whose mothers received 2-4 advice [OR=0.91(95% CI: 0.85-0.97)] compared to neonates whose mothers received only 1 or none. Overall, children to mothers who received ≥ 5 advice had lowest incidence of sepsis [OR=0.83 (95% CI: 0.71-0.97)] Conclusion: Advice on antenatal, prenatal and post natal is significantly reduced with early newborn sepsis. Further research is required to identify specific type of counseling messages that translate into practices and reduce pathways towards early-newborn morbidities.

Keywords: ante natal care, counseling, neonatal sepsis, post natal care

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5623 A Comprehensive Review of Artificial Intelligence Applications in Sustainable Building

Authors: Yazan Al-Kofahi, Jamal Alqawasmi.

Abstract:

In this study, a comprehensive literature review (SLR) was conducted, with the main goal of assessing the existing literature about how artificial intelligence (AI), machine learning (ML), deep learning (DL) models are used in sustainable architecture applications and issues including thermal comfort satisfaction, energy efficiency, cost prediction and many others issues. For this reason, the search strategy was initiated by using different databases, including Scopus, Springer and Google Scholar. The inclusion criteria were used by two research strings related to DL, ML and sustainable architecture. Moreover, the timeframe for the inclusion of the papers was open, even though most of the papers were conducted in the previous four years. As a paper filtration strategy, conferences and books were excluded from database search results. Using these inclusion and exclusion criteria, the search was conducted, and a sample of 59 papers was selected as the final included papers in the analysis. The data extraction phase was basically to extract the needed data from these papers, which were analyzed and correlated. The results of this SLR showed that there are many applications of ML and DL in Sustainable buildings, and that this topic is currently trendy. It was found that most of the papers focused their discussions on addressing Environmental Sustainability issues and factors using machine learning predictive models, with a particular emphasis on the use of Decision Tree algorithms. Moreover, it was found that the Random Forest repressor demonstrates strong performance across all feature selection groups in terms of cost prediction of the building as a machine-learning predictive model.

Keywords: machine learning, deep learning, artificial intelligence, sustainable building

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5622 Breast Cancer Incidence Estimation in Castilla-La Mancha (CLM) from Mortality and Survival Data

Authors: C. Romero, R. Ortega, P. Sánchez-Camacho, P. Aguilar, V. Segur, J. Ruiz, G. Gutiérrez

Abstract:

Introduction: Breast cancer is a leading cause of death in CLM. (2.8% of all deaths in women and 13,8% of deaths from tumors in womens). It is the most tumor incidence in CLM region with 26.1% from all tumours, except nonmelanoma skin (Cancer Incidence in Five Continents, Volume X, IARC). Cancer registries are a good information source to estimate cancer incidence, however the data are usually available with a lag which makes difficult their use for health managers. By contrast, mortality and survival statistics have less delay. In order to serve for resource planning and responding to this problem, a method is presented to estimate the incidence of mortality and survival data. Objectives: To estimate the incidence of breast cancer by age group in CLM in the period 1991-2013. Comparing the data obtained from the model with current incidence data. Sources: Annual number of women by single ages (National Statistics Institute). Annual number of deaths by all causes and breast cancer. (Mortality Registry CLM). The Breast cancer relative survival probability. (EUROCARE, Spanish registries data). Methods: A Weibull Parametric survival model from EUROCARE data is obtained. From the model of survival, the population and population data, Mortality and Incidence Analysis MODel (MIAMOD) regression model is obtained to estimate the incidence of cancer by age (1991-2013). Results: The resulting model is: Ix,t = Logit [const + age1*x + age2*x2 + coh1*(t – x) + coh2*(t-x)2] Where: Ix,t is the incidence at age x in the period (year) t; the value of the parameter estimates is: const (constant term in the model) = -7.03; age1 = 3.31; age2 = -1.10; coh1 = 0.61 and coh2 = -0.12. It is estimated that in 1991 were diagnosed in CLM 662 cases of breast cancer (81.51 per 100,000 women). An estimated 1,152 cases (112.41 per 100,000 women) were diagnosed in 2013, representing an increase of 40.7% in gross incidence rate (1.9% per year). The annual average increases in incidence by age were: 2.07% in women aged 25-44 years, 1.01% (45-54 years), 1.11% (55-64 years) and 1.24% (65-74 years). Cancer registries in Spain that send data to IARC declared 2003-2007 the average annual incidence rate of 98.6 cases per 100,000 women. Our model can obtain an incidence of 100.7 cases per 100,000 women. Conclusions: A sharp and steady increase in the incidence of breast cancer in the period 1991-2013 is observed. The increase was seen in all age groups considered, although it seems more pronounced in young women (25-44 years). With this method you can get a good estimation of the incidence.

Keywords: breast cancer, incidence, cancer registries, castilla-la mancha

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5621 Examining the Factors That Mediate the Effects of Mindfulness on Conflict Resolution Strategies

Authors: Franco Ceasar Agbalog, Shintaro Yukawa

Abstract:

Mindfulness is increasingly being used as a method for resolving conflict. However, less is known about how its positive outcome develops. To better understand the underlying effects of mindfulness on conflict resolution strategies, this study examines the potential mediating factors between them. The researchers hypothesized that Emotional Intelligence (EI) mediates the effects of mindfulness on conflict resolution strategies due to its similar components to the benefits of mindfulness, such as awareness and control of one’s emotions, awareness and understanding of other’s emotions, and cultivation of compassion and empathy. Using a random sampling, 157 participants completed three questionnaires: Five Facet Mindfulness Questionnaire (FFMQ), Trait Emotional Intelligence Questionnaire-Short Form (TEIQue-SF), and Rahim Organizational Conflict Inventory-II (ROCI-II). Utilizing the SPSS Process, results showed a significant relationship between mindfulness and EI. However, among the five approaches to conflict resolution, only the integrating style was significantly related to EI. Following the principle of Mediation Analysis, mindfulness has an indirect effect on integrating style. Moreover, mindfulness and conflict resolution strategies were not significantly related. This is a rather surprising result because research literature has always indicated a positive relationship between the two variables. These findings imply that although integrating style is generally considered the best approach in handling conflict, each style may be appropriate depending on the situation. Mindfulness allows practitioners to have a holistic view of the conflict situation and choose the approach they think best for that specific situation. This could explain why statistically, there is no direct effect of mindfulness on conflict resolution strategies. This work provides basis for the necessity to investigate the factors of conflict instead of the conflict resolution strategies; factors that can be manipulated and may be directly influenced by mindfulness.

Keywords: conflict resolution strategies, emotional intelligence, mindfulness and conflict, ROCI-II integrating style

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5620 Exploring the Illness Experience of Fibromyalgia Patients Using Identity Boxes

Authors: Nicole Brown

Abstract:

This study considers the illness experience of fibromyalgia patients by using identity boxes. The results improve health care professionals' understanding of patient experiences. Additionally, the concept of the identity boxes may offer a practical solution for helping patients accept the diagnosis of fibromyalgia. Fibromyalgia research traditionally refers to pain experiences and relies on questionnaires, surveys, interviews and some narrative analysis. However, due to the variability in symptoms, symptom levels, and locations, these methods may not be best suited to provide an insight into the patient experience. On the other hand, lengthy interview processes are not easily accessible for sufferers of fibromyalgia. In addition to timelines and diary extracts, this study uses identity boxes as its main data collection method. Participants are asked to find items in response to specific questions and to arrange them in their box. The objects represent the patients' experiences holistically. Participants provide photographs of their identity box at each stage of the process and explain their chosen items. The photographs of the identity boxes and the patients' explanations of their objects and their boxes are subjected to interpretative phenomenological analysis. Despite the unique forms of the completed boxes, common experiences are described: the need for comfort, the role of spirituality and the impact of fibromyalgia on everyday life, that it plays a significant role but those patients are determined not to let it rule their lives. The work with the identity boxes has shown beneficial impact due to the reflective nature involved in the tasks. Further investigations will be needed to identify the long-term impact of identity work using such boxes.

Keywords: biographical disruption, fibromyalgia, illness experience, illness narrative

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5619 Effects of the Supplementary for Understanding and Preventing Plagiarism on EFL Students’ Writing

Authors: Surichai Butcha, Dararat Khampusaen

Abstract:

As the Internet is recognized as a high potential and powerful educational tool to access sources of knowledge, plagiarism is an increasing unethical issue found in students’ writing. This paper is deriving from the 1st phase of an on-going study investigating the effects of the supplementary on citing sources on undergraduate students’ writing. The 40 participants were divided into 1 experimental group and 1 control group. Both groups were administered with a questionnaire on knowledge and an interview on attitude related to using sources in writing. Only the experimental group undertook the 4 lessons focusing on using outside sources and citing the original work (quoting, synthesizing, summarizing and paraphrasing) were delivered to them via e-learning tools throughout a semester. Participants were required to produce 4 writing tasks after each lesson. The results were concerned with types and factors on using outside sources in writing of Thai undergraduate EFL students from the survey. The interview results supported and clarified the survey result. In addition, the writing rubrics confirmed the types of plagiarism frequently occurred in students’ writing. The results revealed the types and factors on plagiarism including their perceptions on using the outside sources in their writing from the interview. The discussion shed the lights on cultural dimensions of plagiarism in student writing, roles of teachers, library, and university policy on the rate of plagiarism. Also, the findings promoted the awareness on ethics in writing and prevented the rate of potential unintentional plagiarism. Additionally, the results of this phase of study could lead to the appropriate contents to be considered for inclusion in the supplementary on using sources for writing for future research.

Keywords: citing source, EFL writing, e-learning, Internet, plagiarism

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5618 Algorithm Development of Individual Lumped Parameter Modelling for Blood Circulatory System: An Optimization Study

Authors: Bao Li, Aike Qiao, Gaoyang Li, Youjun Liu

Abstract:

Background: Lumped parameter model (LPM) is a common numerical model for hemodynamic calculation. LPM uses circuit elements to simulate the human blood circulatory system. Physiological indicators and characteristics can be acquired through the model. However, due to the different physiological indicators of each individual, parameters in LPM should be personalized in order for convincing calculated results, which can reflect the individual physiological information. This study aimed to develop an automatic and effective optimization method to personalize the parameters in LPM of the blood circulatory system, which is of great significance to the numerical simulation of individual hemodynamics. Methods: A closed-loop LPM of the human blood circulatory system that is applicable for most persons were established based on the anatomical structures and physiological parameters. The patient-specific physiological data of 5 volunteers were non-invasively collected as personalized objectives of individual LPM. In this study, the blood pressure and flow rate of heart, brain, and limbs were the main concerns. The collected systolic blood pressure, diastolic blood pressure, cardiac output, and heart rate were set as objective data, and the waveforms of carotid artery flow and ankle pressure were set as objective waveforms. Aiming at the collected data and waveforms, sensitivity analysis of each parameter in LPM was conducted to determine the sensitive parameters that have an obvious influence on the objectives. Simulated annealing was adopted to iteratively optimize the sensitive parameters, and the objective function during optimization was the root mean square error between the collected waveforms and data and simulated waveforms and data. Each parameter in LPM was optimized 500 times. Results: In this study, the sensitive parameters in LPM were optimized according to the collected data of 5 individuals. Results show a slight error between collected and simulated data. The average relative root mean square error of all optimization objectives of 5 samples were 2.21%, 3.59%, 4.75%, 4.24%, and 3.56%, respectively. Conclusions: Slight error demonstrated good effects of optimization. The individual modeling algorithm developed in this study can effectively achieve the individualization of LPM for the blood circulatory system. LPM with individual parameters can output the individual physiological indicators after optimization, which are applicable for the numerical simulation of patient-specific hemodynamics.

Keywords: blood circulatory system, individual physiological indicators, lumped parameter model, optimization algorithm

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5617 Laboratory Findings as Predictors of St2 and NT-Probnp Elevations in Heart Failure Clinic, National Cardiovascular Centre Harapan Kita, Indonesia

Authors: B. B. Siswanto, A. Halimi, K. M. H. J. Tandayu, C. Abdillah, F. Nanda , E. Chandra

Abstract:

Nowadays, modern cardiac biomarkers, such as ST2 and NT-proBNP, have important roles in predicting morbidity and mortality in heart failure patients. Abnormalities of serum electrolytes, sepsis or infection, and deteriorating renal function will worsen the conditions of patients with heart failure. It is intriguing to know whether cardiac biomarkers elevations are affected by laboratory findings in heart failure patients. We recruited 65 patients from the heart failure clinic in NCVC Harapan Kita in 2014-2015. All of them have consented for laboratory examination, including cardiac biomarkers. The findings were recorded in our Research and Development Centre and analyzed using linear regression to find whether there is a relationship between laboratory findings (sodium, potassium, creatinine, and leukocytes) and ST2 or NT-proBNP. From 65 patients, 26.9% of them are female, and 73.1% are male, 69.4% patients classified as NYHA I-II and 31.6% as NYHA III-IV. The mean age is 55.7+11.4 years old; mean sodium level is 136.1+6.5 mmol/l; mean potassium level is 4.7+1.9 mmol/l; mean leukocyte count is 9184.7+3622.4 /ul; mean creatinine level is 1.2+0.5 mg/dl. From linear regression logistics, the relationship between NT-proBNP and sodium level (p<0.001), as well as leukocyte count (p=0.002) are significant, while NT-proBNP and potassium level (p=0.05), as well as creatinine level (p=0.534) are not significant. The relationship between ST2 and sodium level (p=0.501), potassium level (p=0.76), leukocyte level (p=0.897), and creatinine level (p=0.817) are not significant. To conclude, laboratory findings are more sensitive in predicting NT-proBNP elevation than ST2 elevation. Larger studies are needed to prove that NT-proBNP correlation with laboratory findings is more superior than ST2.

Keywords: heart failure, laboratory, NT-proBNP, ST2

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5616 Exploring Teacher Verbal Feedback on Postgraduate Students' Performances in Presentations in English

Authors: Nattawadee Sinpattanawong, Yaowaret Tharawoot

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This is an analytic and descriptive classroom-centered research, the purpose of which is to explore teacher verbal feedback on postgraduate students’ performances in presentations in English in an English for Specific Purposes (ESP) postgraduate classroom. The participants are a Thai female teacher, two Thai female postgraduate students, and two foreign male postgraduate students. The current study draws on both classroom observation and interview data. The class focused on the students’ presentations and the teacher’s providing verbal feedback on them was observed nine times with audio recording and taking notes. For the interviews, the teacher was interviewed about linkages between her verbal feedback and each student’s presentation skills in English. For the data analysis, the audio files from the observations were transcribed and analyzed both quantitatively and qualitatively. The quantitative approach addressed the frequencies and percentages of content of the teacher’s verbal feedback for each student’s performances based on eight presentation factors (content, structure, grammar, coherence, vocabulary, speaking skills, involving the audience, and self-presentation). Based on the quantitative data including the interview data, a qualitative analysis of the transcripts was made to describe the occurrences of several content of verbal feedback for each student’s presentation performances. The study’s findings may help teachers to reflect on their providing verbal feedback based on various students’ performances in presentation in English. They also help students who have similar characteristics to the students in the present study when giving a presentation in English improve their presentation performances by applying the teacher’s verbal feedback content.

Keywords: teacher verbal feedback, presentation factors, presentation in English, presentation performances

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5615 Detecting Potential Geothermal Sites by Using Well Logging, Geophysical and Remote Sensing Data at Siwa Oasis, Western Desert, Egypt

Authors: Amr S. Fahil, Eman Ghoneim

Abstract:

Egypt made significant efforts during the past few years to discover significant renewable energy sources. Regions in Egypt that have been identified for geothermal potential investigation include the Gulf of Suez and the Western Desert. One of the most promising sites for the development of Egypt's Northern Western Desert is Siwa Oasis. The geological setting of the oasis, a tectonically generated depression situated in the northernmost region of the Western desert, supports the potential for substantial geothermal resources. Field data obtained from 27 deep oil wells along the Western Desert included bottom-hole temperature (BHT) depth to basement measurements, and geological maps; data were utilized in this study. The major lithological units, elevation, surface gradient, lineaments density, and remote sensing multispectral and topographic were mapped together to generate the related physiographic variables. Eleven thematic layers were integrated in a geographic information system (GIS) to create geothermal maps to aid in the detection of significant potential geothermal spots along the Siwa Oasis and its vicinity. The contribution of total magnetic intensity data with reduction to the pole (RTP) to the first investigation of the geothermal potential in Siwa Oasis is applied in this work. The integration of geospatial data with magnetic field measurements showed a clear correlation between areas of high heat flow and magnetic anomalies. Such anomalies can be interpreted as related to the existence of high geothermal energy and dense rock, which also have high magnetic susceptibility. The outcomes indicated that the study area has a geothermal gradient ranging from 18 to 42 °C/km, a heat flow ranging from 24.7 to 111.3 m.W. k−1, a thermal conductivity of 1.3–2.65 W.m−1.k−1 and a measured amplitude temperature maximum of 100.7 °C. The southeastern part of the Siwa Oasis, and some sporadic locations on the eastern section of the oasis were found to have significant geothermal potential; consequently, this location is suitable for future geothermal investigation. The adopted method might be applied to identify significant prospective geothermal energy locations in other regions of Egypt and East Africa.

Keywords: magnetic data, SRTM, depth to basement, remote sensing, GIS, geothermal gradient, heat flow, thermal conductivity

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5614 Theoretical Approach for Estimating Transfer Length of Prestressing Strand in Pretensioned Concrete Members

Authors: Sun-Jin Han, Deuck Hang Lee, Hyo-Eun Joo, Hyun Kang, Kang Su Kim

Abstract:

In pretensioned concrete members, the transfer length region is existed, in which the stress in prestressing strand is developed due to the bond mechanism with surrounding concrete. The stress of strands in the transfer length zone is smaller than that in the strain plateau zone, so-called effective prestress, therefore the web-shear strength in transfer length region is smaller than that in the strain plateau zone. Although the transfer length is main key factor in the shear design, a few analytical researches have been conducted to investigate the transfer length. Therefore, in this study, a theoretical approach was used to estimate the transfer length. The bond stress developed between the strands and the surrounding concrete was quantitatively calculated by using the Thick-Walled Cylinder Model (TWCM), based on this, the transfer length of strands was calculated. To verify the proposed model, a total of 209 test results were collected from the previous studies. Consequently, the analysis results showed that the main influencing factors on the transfer length are the compressive strength of concrete, the cover thickness of concrete, the diameter of prestressing strand, and the magnitude of initial prestress. In addition, the proposed model predicted the transfer length of collected test specimens with high accuracy. Acknowledgement: This research was supported by a grant(17TBIP-C125047-01) from Technology Business Innovation Program funded by Ministry of Land, Infrastructure and Transport of Korean government.

Keywords: bond, Hoyer effect, prestressed concrete, prestressing strand, transfer length

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5613 An Analytical Approach for the Fracture Characterization in Concrete under Fatigue Loading

Authors: Bineet Kumar

Abstract:

Many civil engineering infrastructures frequently encounter repetitive loading during their service life. Due to the inherent complexity observed in concrete, like quasi-brittle materials, understanding the fatigue behavior in concrete still posesa challenge. Moreover, the fracture process zone characteristics ahead of the crack tip have been observed to be different in fatigue loading than in the monotonic cases. Therefore, it is crucial to comprehend the energy dissipation associated with the fracture process zone (FPZ) due to repetitive loading. It is well known that stiffness degradation due to cyclic loadingprovides a better understanding of the fracture behavior of concrete. Under repetitive load cycles, concrete members exhibit a two-stage stiffness degradation process. Experimentally it has been observed that the stiffness decreases initially with an increase in crack length and subsequently increases. In this work, an attempt has been made to propose an analytical expression to predict energy dissipation and later the stiffness degradation as a function of crack length. Three-point bend specimens have been considered in the present work to derive the formulations. In this approach, the expression for the resultant stress distribution below the neutral axis has been derived by correlating the bending stress with the cohesive stresses developed ahead of the crack tip due to the existence of the fracture process zone. This resultant stress expression is utilized to estimate the dissipated energydue to crack propagation as a function of crack length. Further, the formulation for the stiffness degradation has been developed by relating the dissipated energy with the work done. It can be used to predict the critical crack length and fatigue life. An attempt has been made to understand the influence of stress amplitude on the damage pattern by using the information on the rate of stiffness degradation. It has been demonstrated that with the increase in the stress amplitude, the damage/FPZ proceeds more in the direction of crack propagation compared to the damage in the direction parallel to the span of the beam, which causes a lesser rate of stiffness degradation for the incremental crack length. Further, the effect of loading frequency has been investigated in terms of stiffness degradation. Under low-frequency loading cases, the damage/FPZ has been found to spread more in the direction parallel to the span, in turn reducing the critical crack length and fatigue life. In such a case, a higher rate of stiffness degradation has been observed in comparison to the high-frequency loading case.

Keywords: fatigue life, fatigue, fracture, concrete

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