United Arab Emirates University
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Limiting the Shareholder and Partner Liability in Joint-Stock and Limited Liability Companies: A Comparative Study Between Kuwait and U.S Laws
Get PDFpartner liability exemptions when faced with an attempt to pierce the corporate veil and attach individual liability for ongoing business decisions. The issue is that although piercing the corporate veil rule serves as an important tool for holding decision-makers accountable for misconduct in public companies and limited liability companies, the Kuwaiti legislature did not adopt this exemption If the promoter or the partner uses the company for fraudulent or illegitimate purposes, If he treats the company’s funds as his own personal funds, or if he does not separate his personal interest from the company’s interest, or if he causes incurring obligations by the company even though he certainly or purportedly knows that the company is not able to perform such obligations on their maturity, or if such obligations have been incurred due to his gross negligence or wrongdoing, if he violates the provisions of the Law or the company’s Memorandum of association or Articles of Incorporation, or if he exceeded its authority or committed fraud or gross negligence in carrying out his duties. Thus, and through the comparative-analysis method, this study seeks essentially to answer the question of whether shareholder and partner liability can be pierced under Kuwaiti law. This is achieved through an understanding the governing philosophical basis for such an exemption through analyzing the piercing of the corporate veil doctrine as it exists in the United States. Finally, this study found that an absolute limited protection on shareholder and partner liability would adversely affect potential the rights of the company’s other financial stakeholders
ESTIMATING MARS SURFACE WIND STRESS AND DUST LIFTING USING REANALYSES BASED ON EMM AND OTHER SPACECRAFT OBSERVATIONS
Get PDFStudying Mars offers insights into terrestrial planet evolution and informs future human expeditions. This thesis examines dust dynamics in Mars’ lower atmosphere, focusing on understanding its weather and climate. We investigate the role of Near-Surface Wind Stress (NSWS) in dust lifting, using six reanalysis datasets, respectively: MACDA, EMARS, OpenMARS, ACS–TIRVIM (ExoMars observations of the MY34 Global Dust storm), EMM1 and EMM2. Following the parameterization approach by Newman et al. (2002a), areas of agreement and discrepancy among datasets were identified. Time series analysis revealed consistent results where datasets overlap temporally. Some differences were expected and shown due to the different Global Climate Models (GCM) used to generate each dataset. These variations might be due to the number of vertical levels in the models and need further investigation. Notably, global dust storms during Martian years 25, 28 and 34 resulted in increased drag velocities and vertical fluxes. MACDA results, though smaller, followed the same trends, suggesting the impact of model parameters. Developing enhanced datasets with better resolution can provide more reliable insights into Martian atmospheric dynamics. Future work should explore new methods with variable thresholds and roughness values, enhancing the accuracy and reliability of measured dust lifting rates on Mars
MOLECULAR AND BIOCHEMICAL ANALYSIS OF CYTOCHROME P450 2C19 AND 2D6
Get PDFPharmacogenomics (PGx) is a relatively new field of study. It links genetics to pharmacology since it deals with the influence of the genetic makeup of the individual on their ability to respond to specific medications. Some of the most important genes in this field, dubbed very important pharmacogenes (VIPs), belong to the cytochrome P450 (CYP) superfamily of drug metabolizing enzymes. The two members of this family that are the main focus of this thesis are CYP2C19 and CYP2D6. They play major roles in the metabolism of numerous medications, and it is therefore imperative that variations within those genes in various populations are detected in an efficient and timely manner, as well as establishing their impact on the function of the encoded enzymes.In this study, seven variants in CYP2C19 that have been detected in the Emirati population were analysed to determine their potential effects on the enzyme’s activity. Major aims of this thesis were to perform in silico analysis, generate the seven target variants in mammalian expression vectors, express them in mammalian cell lines, and measure the resulting enzyme’s activities. The variants were successfully generated by site-directed mutagenesis using two expression vectors as templates and were expressed in COS and Hek293T cells. However, the enzymatic activity tests using lysates from those cells were inconclusive and, therefore, further analysis, perhaps using different kits, are needed to further establish the impact of those variants.For CYP2D6, a long-range PCR-based technique was optimized and utilized to detect gene copy numbers using DNA extracted from blood samples isolated from psychiatric patients to determine their CYP2D6 metabolic status. In particular, this test was used to detect if the patients have a deletion star allele (CYP2D6*5) or duplication of CYP2D6. The results indicate that this approach could be used to implement genetic testing to determine CYP2D6 copy numbers in patients requiring medication metabolized by this enzyme
DEVELOPMENT OF GUIDANCE, NAVIGATION, AND CONTROL SYSTEMS FOR MULTI-SPACECRAFT ASSEMBLY IN PROXIMITY OPERATIONS
Get PDFThis thesis presents the development of Guidance, Navigation, and Control (GNC) algorithms for multi-spacecraft assembly in proximity operations. A 3-DOF mathematical model of spacecraft relative translational motion is derived using the Euler-Lagrange method. Additionally, a 6-DOF mathematical model of spacecraft relative translational and rotational motion is derived using the twistor method, with consideration for the kinematic coupling effect. A new Linear Time-Invariant (LTI) model is developed based on the twistor model, which is utilized in the design of the GNC systems. Both LTI Model Predictive Control (MPC) and Linear Time-Varying (LTV) MPC algorithms are employed to develop Guidance and Control (G&C) systems using the 3-DOF translational model. These algorithms consider mission constraints such as collision avoidance, Line-of-Sight (LOS), and input saturation. A novel linear representation of the LOS constraint is developed using the Taylor expansion to simplify the optimization problem while avoiding ambiguity. Furthermore, decentralized G&C systems are developed using the Discrete-Time Periodic Riccati (DTPR) method, based on a discrete Linear Time-Periodic (LTP) model of spacecraft relative translational motion. The stability of the system and the synchronization of the members are analyzed using the Lyapunov method. In addition, a new technique is developed to prove the stability of multi-agent discrete LTP systems under input saturation using the invariant-set method. The twistor model is also utilized to design G&C systems using decentralized MPC and Linear Quadratic Regulator (LQR) methods. The optimal trajectories of the spacecraft are generated using the Lagrange method, and the results are compared to identify the most efficient method. Regarding the navigation systems, the Unscented Kalman Filter (UKF) is employed to develop two relative navigation systems for spacecraft relative 6-DOF motion. First, the Taylor expansion is utilized to obtain the residuals of the state covariance and measurement noise covariance matrices. Second, the State Noise Compensation (SNC) method is utilized to determine the first-order approximation of the residuals, while the Stirling Interpolation Formula (SIF) is employed to evaluate the second-order approximation. The integrated GNC systems are verified through real-time testing using dSPACER® SCALEXIO LabBox, demonstrating the ability to apply the proposed systems in practical applications
RISK FACTORS FOR EATING DISORDERS AMONG UAE UNIVERSITY STUDENTS: THE ROLE OF FAMILY DYSFUNCTION AND ATTACHMENT STYLES
Get PDFA topic that is highly researched nowadays in the UAE is eating disorders (EDs). They are characterized by a persistent disturbance of eating-related behaviors that can result in altered consumption of food. Literature has suggested that there are several factors that can make an individual vulnerable to EDs, including family dynamics and attachment styles. This thesis is an attempt to examine the impact of family dynamics and early attachment on mental health wellbeing. The main objective is to examine how family dysfunctional concepts (rigid, chaotic, enmeshed, and disengaged) and attachment styles (close, dependent, and anxious) can be potential risk factors for EDs in university students in the UAE. Using a cross-sectional design with convenient sampling, a survey was distributed to 375 university students at two universities in Al Ain, UAE. The survey encompassed demographic information, the Family Adaptability and Cohesion Evaluation-IV (FACES-IV) to examine the family dysfunctional type, the Eating Attitude Test-26 (EAT-26) to measure the risk of developing EDs, and the Revised Adult Attachment Scale (RAAS) to examine the attachment style. For family dysfunctional concepts, results of multiple regression analyses indicated that chaotic and rigid family dysfunctional styles were related to the risk of EDs development. Specifically, rigid and chaotic dysfunctional styles were associated with dieting behaviors and bulimia and food preoccupation behaviors. In addition, a relationship between rigid family dysfunctional style with oral control behaviors was also revealed. For attachment styles, multiple regression analyses revealed that anxious and close attachment styles were associated with the risk of EDs development. The results also showed that anxious attachment style was related to dieting and oral control (R2=.018, behaviors. Moreover, close and anxious attachment styles were associated with bulimia and food preoccupation behaviors. In conclusion, rigid and chaotic family dysfunction and close and anxiety attachment styles were suggested to play a role in Eds development and EDs behaviors too. This study highlighted the multifaceted nature of EDs, emphasizing the central role that family dysfunction and attachment styles play in their development
DATA-DRIVEN MODELING OF STUDENT PERFORMANCE IN THE TIME OF DISTANCE LEARNING
Get PDFOne of the important aspects that all academic institutions work towards improving is Student Performance. It is obviously the primary indicator of success or failure of institutions. Student performance predictions are vital to instructors and educational decision makers to help, across all levels, tailor learning according to the students’ needs. Therefore, it is essential for Higher Education Institutions to predict student performance in distance learning which has been, and remains, the primary method of learning in some countries due to Corona Virus pandemic. For this reason, this research is going to predetermine a fitting definition of student performance in time of distance learning by surveying literature and collecting new effective factors affecting students’ performance. New concepts and attributes are discovered and considered in the new definition. Furthermore, a primary objective of this thesis is to build a prediction model for student performance during distance learning, where the new definition and its subsequent attributes are considered. The data-driven model is empirically validated, and the obtained results show the outperformance of our proposed approach; particularly the appropriateness of the introduced student performance definition as well as the machine learning based technique from which the student performance prediction model is derived. We strongly believe that such a model will benefit the educators and guide them on how to accurately make decisions based on student performance in the distance learning settings
TEACHER’VIEW ABOUT DUAL ENROLMENT OF STUDENT WITH DISABILITIES IN SPECIAL AND INCLUSIVE PRIVATE SCHOOL
Get PDFThe education of children with disabilities is challenging. Special and inclusive schools cannot offer meaningful access to education to children with disabilities. Currently, schools strive to provide access to education in a dual context: a certain number of days at inclusive schools and others at special schools. However, information on how teachers are contending with such practices is limited. This study explored teachers’ views on the education of students with disabilities in the dual enrolment education system in the United Arab Emirates (UAE). The social education model was conceptualised to understand teachers’ perceptions, collaborative efforts, resources and challenges to dual enrolment practices. The study sample comprised 10 teachers: five special education teachers and five general education teachers. They were recruited from Al Ain, the third largest city in the UAE. An interview guide was developed based on the research question and the study framework to collect data from the study participants. The data were subjected to thematic analysis following these guidelines: reading, coding, categorising, thermalizing and reporting. The findings of this study indicated that teachers had positive views on dual enrolment and appreciated the current practice of providing accessible education to children with disabilities in two settings. Despite the participants’ positive responses to dual enrolment, results showed poor implementation of the dual enrolment system for students with disabilities. This finding is due to a lack of collaboration, communication and a shared plan to support the development of children with disabilities across schools. The study concludes with a recommendation for a national framework to guide the implementation of a dual enrolment system in the UAE
ASSOCIATION OF HUMAN LEUKOCYTE ANTIGEN (HLA) ALLELES WITH ATOPIC DERMATITIS IN THE UAE POPULATION
Get PDFIn the face of the increasing global prevalence of Atopic Dermatitis (AD), a chronic inflammatory skin condition, this thesis seeks to elucidate the genetic underpinnings of AD within the UAE population. Previous literature has underscored the ethnic-specific involvement of Human Leukocytes Antigen (HLA) genetic variations, especially within HLA-A and HLA-DRB1 genes, in the pathogenesis of various skin diseases, including AD. Leveraging this knowledge, our research specifically aimed to investigate the association between these HLA variants and AD in the UAE. Utilizing a comparative approach, the frequencies of HLA-A and HLA-DRB1 variants were assessed in AD patients vis-à-vis a control group. Our data, based on frequency data and corroborated by z-test and chi-square statistical analyses, indicated a non-specific association of any of the HLA-A or HLA-DRB1 variants within AD susceptibility or protection
INVESTIGATION OF POOL BOILING HEAT TRANSFER ON MODIFIED COPPER AND ALUMINUM SURFACES
No full textThis thesis presents an investigation of pool-boiling heat transfer using the surfacemodification method. The studied boiling surfaces were smooth and rough pin-fins embedded on the copper and aluminum surfaces. This study visualizes bubble formation and departure diameter. Experimental testing aims to predict the heat transfer coefficients for different heat fluxes over smooth and rough pin-finned surfaces. The surface modification method allows changing the boiling surface characteristics, which can lead to enhanced heat transfer. Several factors were studied, including the heat-transfer coefficient, heat flux, bubble departure diameter, and formation time. Four surfaces were used for conducting the pool boiling experiment: a smooth copper surface, a pin-fin copper surface with a width and length of 1 mm and a height of 2 mm with a spacing of 2 mm, a smooth aluminum surface, and a rough aluminum pin-finned surface with 0.5×0.5×1 mm with and a spacing of 2 mm. The experimental testing results compare the smooth and rough surfaces for each of the copper and aluminum materials, showing the differences between the bubble diameter sizes and the bubble formation and departure times at different heat fluxes (low, medium, and critical flux). It was found that the bubble diameter, bubble departure, and formation time increased as the heat flux on the smooth and rough pin fins increased. The study investigated the bubble diameter size and formation/departure times for different heat fluxes on smooth and pin-finned copper and aluminum surfaces. The results are as follows: the bubble diameter sizes (low, medium, and critical heat fluxes) on the smooth copper surface were 0.2803 cm, 0.437 cm, and 0.67 cm. While the bubble formation and departure time (low, medium, and critical heat flux) were 0.2859 s,0.305 s, and 0.4025 s. As for the pin-finned copper surfaces, the bubble diameter sizes (low, medium, and critical heat fluxes) were 0.745 cm, 1.38 cm, and 1.95 cm and the bubble formation and departure times on the pin-finned copper were 0.184 s, 0.207 s, and 0.417 s. For the smooth aluminum surface, the bubble diameter size (low, medium, and critical heat fluxes) were 0.63 cm, 0.96 cm, and 1.27 cm, and the bubble formation and departure times (low, medium, and critical heat fluxes) were 0.27 s, 0.36 s, and 0.40 s. The bubble formation and departure times (low, medium, and critical heat fluxes) were 0.27 s, 0.36 s, and 0.40 s.
The pin-finned aluminum surface had bubble diameter sizes (low, medium, and critical heat fluxes) of 0.24 cm, 0.30 cm, and 0.83 cm. While the bubble formation and departure time (low, medium, and critical heat fluxes) were 0.11 s, 0.13 s, and 0.21 s, respectively. It was concluded that the rough pin-finned copper surface showed an improved boiling heat transfer coefficient and higher heat flux at lower wall superheat temperatures than the smooth surface. In addition, a Computational Fluid Dynamics (CFD) simulation for boiling heat transfer was developed to conduct a comparison with the experimental results and to study the volume fraction of vapor, velocity, and temperature of the generated bubbles
USE OF ROOT ENDOPHYTIC ENTEROBACTER SP. SA187 FOR THE IMPROVEMENT OF ABIOTIC STRESS TOLERANCE OF TOMATOES GROWN UNDER GREENHOUSE CONDITIONS
No full textAgricultural productivity is largely affected by climate change. These climatic alterations translate into adverse abiotic stress conditions, such as heat, drought, and salinity, which restrict the geographical distribution of plants and limit their crop yields. Extreme conditions primarily affect semiarid and arid regions, causing severe environmental and economic repercussions. Plant growth-promoting rhizobacteria (PGPR) have been proposed to overcome these challenges. The desert plant endophytic bacterium Enterobacter sp. SA187 has shown beneficial effects on plant growth and salt stress tolerance in the model plant Arabidopsis thaliana in vitro, as well as under field conditions in different crops. This study aimed to assess the effectiveness of Enterobacter SA187 in terms of plant growth, antioxidant enzyme activity, oxidative damage, and transcriptomic changes under various stress conditions. Tomato plants were subjected to a variety of stress treatments, including salt and heat, with and without bacterial inoculation. We evaluated plant growth, fresh and dry weight, chlorophyll content, Na+/K+ ratio, and activities of the antioxidant enzymes SOD, POD, and CAT, along with transcriptomic changes. According to our findings, the inoculation of plants with Enterobacter SA187 considerably enhanced plant growth and stress tolerance. The treated plants showed increased antioxidant enzyme activity and decreased oxidative damage, suggesting a more effective defense mechanism against reactive oxygen species induced by stress. Additionally, the Na+/K+ ratio in leaves and roots decreased when Enterobacter SA187 was present, indicating enhanced ion homeostasis and decreased sodium uptake under challenging circumstances. Transcriptome sequencing using RNA-seq of tomato roots grown under salt and heat stress revealed the upregulation and downregulation of certain pathway genes related to abiotic stress, such as HKT, SOS, and HFA2. The potential of root endophytic bacteria, such as Enterobacter SA187, as biotechnological tools for improving crop stress tolerance is highlighted by these findings. This study advances how plants and microbes interact to support plant development and stress resistance. Further research is required to determine the effectiveness of Enterobacter SA187 in actual agricultural contexts and to clarify the underlying processes of these interactions. These findings indicate the use of root endophytic bacteria to increase crop stress tolerance, which has implications for sustainable agriculture and food security