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.24 0Item Restricted Genetics of Heat Tolerance in the Bengal and Assam Aus Panel of Rice(University of Aberdeen, 2024-07) Alonazy, Dalal; Price, Adam; Norton, Gareth; Barker, MartinRice (Oryza sativa L.) is considered as the main stable food and largest grain crop in many Asian countries since they rely on it for basic nutrition. During the past few years, the temperature in rice-growing regions has been rising, and extreme high temperature events are increasingly frequent, potentially causing crop damage. Heat stress caused by rising temperature over the optimal range is a significant abiotic stress affecting rice production. Heat stress can negatively affect plant growth, development and productivity, causing a loss of yield. Therefore, developing heat tolerant rice varieties is essential. In this work, heat tolerance was evaluated in 204 rice cultivars, mostly from Bengal and Assam Aus Panel (BAAP). High heat tolerant genotypes were identified using two approaches: spikelet fertility and chlorophyll fluorescence. For spikelet fertility, the heat tolerant genotypes identified were ARC 14965, ARC 10392 and Goria. For chlorophyll fluorescence, the genotypes identified were KALI AUS, Code No BI 93 and AUS 130. Genome-wide association (GWA) mapping was conducted on the heat tolerance trait with two million SNPs using an efficient mixed model (EMMA). The total number of QTLs associated with traits related to heat tolerance identified were 23 in fertility trait and 10 QTLs in photosynthetic trait. A number of these QTLs contained functional candidate genes. A total of seven candidate genes were identified for control/treatment ratio; SEC14, Hsp20, AP2/ERF, WRKY28, miRNA156, OsDjC56 and ZOS6-06 and three for QY trait after 60 minutes; PHD13, OsSTA65 and CGN. Additionally, RNA-sequencing analysis (RNA-seq) was conducted on spikelet fertility trait and well-known heat tolerant genes were detected such as (OsMYB55, OsHTASb and OsHSFC1b). Through the combination of GWA and transcriptomic analysis two excellent candidate genes associated with heat tolerance in rice were identified, namely; miRNA156 and OsDjC56. In addition, the candidate gene CGN in the leave study differentially expressed in the RNA-seq. In conclusion, the heat tolerant genotypes and QTLs and candidate genes identified in this study could be serve as valuable resource for further advanced research in rice heat tolerance and for breeding programs aimed at enhancing sustainable rice production. Such work could make an important contribution in supporting global food security worldwide.26 0