Saudi Cultural Missions Theses & Dissertations
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Item Restricted Optimizing Construction Productivity Through Climate-Specific Heat Stress Management(Purdue University, 2024-12) Alreshoodi, Majed; Hastak, MakarandThis research investigates the combined impact of heat stress and fatigue on construction worker productivity in two climatically distinct regions: a humid coastal area and a dry inland region. Using Wet Bulb Globe Temperature (WBGT) as a measure of heat stress and incorporating working hours to account for fatigue, the research employs Monte Carlo simulations to model productivity variations across different work shift configurations and environmental conditions. The research focuses on two high-intensity construction tasks, with baseline productivities established through field observations. Simulation results reveal significant differences in optimal work strategies between the two regions, considering both heat stress and cumulative fatigue effects. In the humid coastal region, shifts starting between 12:00 AM and 4:00 AM showed the highest productivity, with the most effective work ban period from 10:00 AM to 1:00 PM. In contrast, the dry climate allowed for a wider window of productive hours, with the current 12:00 PM to 3:00 PM ban proving most effective. The research also explored the impact of breaks, indoor versus outdoor work, and various shift lengths on productivity, taking into account how fatigue accumulates under different environmental conditions. Model validation against field data demonstrated high accuracy, with mean productivity differences of -4.00% for Jubail and 1.19% for Qassim. The findings highlight the need for climate-specific work strategies and policies that address both heat stress and fatigue to optimize construction productivity while ensuring worker safety. The research provides valuable insights for industry practitioners and policymakers, suggesting that tailored approaches to managing both environmental stress and worker fatigue can significantly improve productivity and well-being in challenging climatic conditions.33 0Item Restricted Tapping the untapped genetic potential of moth bean (Vigna centifolia) – a high temperature stress tolerance legume.(Saudi Digital Library, 2023-12-12) Taher, Aeshah; Bhosale, RahulAbiotic stresses, such as drought and extreme temperatures, pose significant challenges to crop production. Understanding the impact of abiotic stress factors on crop plants is crucial for implementing effective strategies in unfavourable agricultural environments. Moth bean (Vigna aconitifolia), considered one of the earliest cultivated crops within the Vigna genus, stands out as a robust legume known for its exceptional resilience to drought and high-temperature conditions, making it a staple in arid regions. In this research, our focus revolves around unravelling the intricate dynamics of root and shoot growth, delving into the intricate root architecture system (RAS), all in pursuit of uncovering the mechanisms underpinning the plant's adaptability and the key traits associated with its remarkable abiotic stress tolerance in wild moth bean (TN67) and cultivated moth bean (ICPMO056). Methodology: Heat stress conditions were induced by subjecting seedlings to a 7-day exposure at 40°C prior to harvesting. Drought stress was simulated through limited irrigation, with both short-term (7 days) and long-term (27 days) durations. To comprehensively assess the combined impact of concurrent drought and heat stress, a 7-day experiment was conducted involving three distinct treatments: Optimal conditions, Heat, and a combination of Heat and Drought. Various parameters were measured, including primary root length (PRL), root and shoot mass, leaf number and size, and hypocotyl length. Results and Discussion: Based on our findings, TN67 (wild variety) demonstrates greater abiotic stress tolerance compared to ICPMO 56 (Commercial variety), as indicated by its less pronounced responses to the experimental conditions. Plant phytohormones, such as abscisic acid and auxin, are known to play a significant role in stress tolerance. To investigate their impact, hormone treatment experiments were conducted. The results revealed a consistent inhibition of primary root length but a concurrent promotion of lateral root growth, which is considered a stress tolerance mechanism. Conclusion: A deeper understanding of the underlying factors driving this inter-genotypic variation in stress sensitivity requires further investigation. Exploring the molecular basis of these differences presents an important direction for future research, which could lead to the development of more resilient crop varieties capable of withstanding the challenges posed by climate change-induced abiotic stresses.19 0Item Restricted Differences in Changes in Blood Pressure During Passive Heating(Saudi Digital Library, 2023-11-08) Alshehri, Adham; Leicht, Christof; O’Donnell, EmmaThe human body has developed intricate physiological processes in response to changes in the external environment; the aim of these processes is to maintain homeostasis. The aim of this study was to evaluate the effects of passive heating on blood pressure in both sexes in order to determine if these differences will exist. The exposure to passive heating in 15 healthy adults did not show statistical significance concerning the effects of heating (continuous and intermittent), time (pre- and post-trial), and interaction (heating × time) on brachial and central diastolic blood pressure nor brachial and central systolic blood pressure (P > 0.05). However, Females experienced a greater reduction in blood pressure during passive heating than males (P < 0.05). In conclusion, the results did not support the theory that passive heating would cause a sudden drop in blood pressure; however, a greater drop in blood pressure during passive heating was observed in females compared to males.9 0Item Restricted Sex Differences in Changes in Blood Pressure During Passive Heating(Saudi Digital Library, 2023-11-08) Alshehri, Adham; Leicht, ChristofThe human body has developed intricate physiological processes in response to changes in the external environment; the aim of these processes is to maintain homeostasis. The aim of this study was to evaluate the effects of passive heating on blood pressure in both sexes in order to determine if these differences will exist. The exposure to passive heating in 15 healthy adults did not show statistical significance concerning the effects of heating (continuous and intermittent), time (pre- and post-trial), and interaction (heating × time) on brachial and central diastolic blood pressure nor brachial and central systolic blood pressure (P > 0.05). However, Females experienced a greater reduction in blood pressure during passive heating than males (P < 0.05). In conclusion, the results did not support the theory that passive heating would cause a sudden drop in blood pressure; however, a greater drop in blood pressure during passive heating was observed in females compared to males.11 0