United Arab Emirates University
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EVALUATION OF NATIVE PLANT INTEGRATION, SUBSOIL AMENDMENT, AND ‘FOODSCAPING’ AS MEANS OF INCREASING THE ENVIRONMENTAL FEASIBILITY OF PUBLIC URBAN GREENERY IN THE GULF REGION
Get PDFPublic parks and gardens greatly contribute to the residential and touristic value of cities of the Gulf Region, but their maintenance is associated with high environmental and economic costs. The high potential evapotranspiration and summer temperatures greatly limit the choice of suitable landscaping plants, and light sandy soils with a high weed potential challenge the water management. The United Arab Emirates is characterized by a rapid urban development and population growth, resulting in increasing competition between green amenities and crop farming for irrigation water, cultivable land, and workforce. Various strategies and technologies have been proposed to increase the resource use efficiency of UAE’s urban greenery, such as the replacement of exotic by native xerophytic vegetation, amendment of the soil, water saving irrigation practices, as well as the integration of crop production with ornamental plantations (‘foodscaping’). However, little is known about how such techniques could be integrated into existing landscape management concepts, and there is a need to comparatively assess resource saving potentials. For this purpose, two field experiments were conducted in public urban parks in the city of Al Ain, UAE, as part of the present study. The first one tested eight native and four exotic plant ornamental species for their performance under four levels of supply with mineral fertilizer and irrigation water in form of treated sewage effluent (TSE). One year after establishment, the native plants provided a similar ornamental value at up to 70 % reduced irrigation water expenditure compared with standard exotic plant stands. The native plants were also found to have a positive impact on the soil physical and chemical properties. The second field experiment tested the hypothesis that subsoil amendment in combination with water supply to the subsoil via deep pipes would increase the water use efficiency of ornamental plant stands. The results of this experiment revealed that, irrespective of the mode of water supply, the native plant species grew more biomass and tended to outcompete neighbouring exotic plants when grown in mixed stands. The soil amendment had no impact on the plant performance, but deep pipe irrigation reduced the emergence of weeds. Based on literature research, site observations, and satellite image mapping, the present study also evaluated the potential contribution of foodscaping to Al Ain’s supply with fresh fruits and vegetables. This study revealed that foodscaping could potentially contribute around 10 % to the total fruit and vegetable consumption of urban residents, which is notable, given that the Gulf Region currently imports more than 90 % of its food. For a preliminary assessment of risks pertaining to urban crop production, date fruits from palms growing along roads within and outside of Al Ain were sampled and analysed for their element concentrations. The results revealed that some fruits grown near roads contained elevated levels of certain heavy metals, likely from atmospheric deposition. Based on the results of the present study it is concluded that the resource saving potential of alternative soil amendment or irrigation technologies for public urban greenery is rather low. A far greater potential seems to lie in a modification of the composition of urban landscape plantations. It is recommended that strategies for the integration of native plants and crops into urban gardens and parks are further developed. These would need to take differences in competitive strength between native and exotic plant species into account, as well as the potential contamination of plant material in the proximity of roads
UAE STUDENTS’ PERCEPTIONS OF THE RELATION BETWEEN STUDYING SCIENCE THROUGH STEM AND THEIR ASPIRATIONS FOR STEM CAREERS: THE CASE OF GRADES 9 AND 10 IN AL FUJAIRAH
Get PDFScience, technology, engineering, and mathematics (STEM) education in the United Arab Emirates (UAE) is receiving growing attention because the country’s massive economic growth has created a need for STEM-qualified graduates. Educational policymakers and curriculum developers in the UAE are, therefore, advocating the development and implementation of STEM at all academic levels. Studies have emphasized that STEM education positively affects students’ ability to solve problems, be innovative, think critically, and be technology literate. This quantitative study aimed to explore students’ level of interest in STEM and the impact of studying STEM on their future career aspirations. Specifically, this study examines the following research questions: (1) what is the level of interest in STEM among ninth and tenth-grade students in Al Fujairah? (2) What is the relation between studying science through STEM and students’ aspirations for STEM careers? (3) Are there significant genderbased and grade-level differences among students in their career aspirations and interest in STEM? (4) What is the effect of students’ participation in STEM lessons on their attitudes toward STEM? A quantitative approach was adopted to collect data from grades 9 and 10 students using a survey. The sample consisted of 1,100 students from grades 9 and 10 for the first survey and the researcher considered 104 students to test their interest in STEM from pretest and posttest STEM schools for the second survey. A repeated-measures analysis of variance revealed that students in STEM programs had significantly different career aspirations and future goals compared with those not in STEM. To investigate the relation between STEM field interest and career goals, Pearson product-moment correlation coefficients were calculated. Interest in science and the desire to pursue careers in the field were positively correlated. Further, the results demonstrated a statistically significant impact of gender (i.e., girls show more interest than boys). Considering the significance of STEM education today, activities can be conducted to increase students’ interest and engage them in STEM. Findings may drive positive developments in UAE STEM education by informing policymakers regarding the advantages of STEM classes in enhancing students to enroll in STEM classes and pursue STEM careers
SYNTHESIS AND STRUCTURE-PROPERTY RELATIONSHIPS OF SUSTAINABLE NANOSTRUCTURED MATERIALS TOWARDS ENERGY AND ENVIRONMENT APPLICATIONS
Get PDFThis doctoral research aims to advance clean energy technologies by developing specialized nanostructured materials. The study covers significant research themes, each forming separate sections in the thesis, explaining the important role of nanostructures in enhancing the efficiency and sustainability of energy devices and photocatalytic technologies. The enduring effort toward stabilizing and improving the efficiency of dye-sensitized solar cells (DSSCs) has stirred the solar research community to follow innovative approaches. The primary objective of the research is centered on electrode materials design, which improves photoanodes\u27 light-harvesting efficiency (LHE). To improve the Photoanode of DSSCs, a Metal-Organic Framework (MOF) derived porous photoanodes were developed which can effectively absorb dye molecules and improve LHE, resulting in high power conversion efficiency (PCE). Doping is a prospective methodology to tune the bandgap and broaden spectral absorption. Hence, a novel and cost-effective synthesis of high surface area transition metal (TM) doped TiO2 nanocrystals (NCs) via the MOF route for DSSCs is explored. The TM dopants (i.e., Co, Mn, Fe, Ni), in TiO2 lead to enhanced light absorption in the visible region. Among the TM dopants, a remarkable PCE of 7.03% was obtained for nickeldoped samples with increased Jsc (14.66 mA/cm2) due to the bandgap narrowing and porous morphology of TiO2. As a second objective, platinum nanoparticles (Pt NPs) incorporated into multiwalled carbon nanotubes (MWCNT) composites with lower Pt content were developed as an efficient bifacial counter electrode (CE) material for DSSC applications. Pt NPs were homogenously decorated over the MWCNT surfaces using a simple polyol method at relatively low temperatures. CEs fabricated using Pt/MWCNT composites exhibited excellent transparency and power conversion efficiencies (PCE) of 6.92 % and 6.09% for front and rear illumination. These results emphasize the significance of tailored nanostructures in optimizing the performance of optoelectronic devices and are expected to bring significant advances in DSSCs. Furthermore, as a third objective, the developed Iron (Fe) doped MOF derived materials were applied for their performance studies for supercapacitor applications. The pseudo capacitors were fabricated using both TiO2/FeTiO2 material as electrodes with KOH electrolyte at 0.6 V and studied the super capacitive performance using CV, GCD, and EIS analysis. A remarkable cycling life of 78% up to 25000 cycles and a superior capacitance of 925 F/g were obtained using the synthesized material. The fabricated asymmetric supercapacitor exhibits supercapacitive performance, favorable rate capability, and exceptional flexibility. The obtained properties demonstrate that nanostructured Fe-doped TiO2 is an attractive active electrode material for high-performance supercapacitor applications. As a fourth objective, an efficient composite material based on Ag NPs, MOF-derived Cobalt-doped TiO2 NPs, and MXene is developed for clean water production via photocatalysis. A simple one-pot solvothermal method fabricated Ti3C2 MXene decorated with MOF-derived Cobalt-doped TiO2 and Ag nanoparticles (Ag NPs). The composite material combines the unique antibacterial properties of Ag NPs, high absorptive properties of metalorganic framework (MOF)-derived cobalt-doped titanium dioxide (TiO2), and catalytic properties of MXene. The resulting composite materials were characterized thoroughly to examine their effectiveness in the photocatalytic degradation of industrial dyes (methylene blue and methyl orange). The results show that 0.025 mg and 0.05 mg of the composite can degrade the MO and MB dyes respectively under the action of sunlight in 60 min
CHARACTERIZATION OF THE POTENTIAL OF MOUSE MAMMARY TUMOR VIRUS (MMTV) TO DISRUPT MAMMARY EPITHELIAL CELL GENE EXPRESSION AND ITS CONSEQUENCES
Get PDFThe mouse mammary tumor virus (MMTV) is a betaretrovirus known to induce breast cancer in mice. Unlike most other tumorigenic retroviruses that target hematopoietic cells, MMTV primarily targets mammary epithelial cells for infection and transformation. This makes it a valuable model for studying human breast cancer, which also originates from mammary epithelial cells. MMTV is transmitted through milk, with the highest expression occurring in lactating mammary glands due to the mammary gland enhancer and hormone-responsive elements (HREs) in its promoter. However, not much is known about how MMTV affects these cells at the molecular level. Since elevated hormonal induction during pregnancy and lactation enhances MMTV expression, we used the HC11 mouse mammary epithelial cells, differentiable by prolactin, to investigate how MMTV impacts its gene expression under normal and differentiated states. The hypothesis under test proposed that MMTV enhances mammary cell differentiation to increase its expression and viral titers for transmission to the progeny. To test this hypothesis, we established a stable HC11 cell line constitutively expressing MMTV and successfully differentiated these cells through various protocols. mRNAseq analysis of undifferentiated and differentiated cells revealed MMTV’s surprising ability to induce global downregulation of ~ 74 & 70% of host genes, respectively. Quantitative reverse transcriptase PCR (RTqPCR) validated the disruption of the expression of key differentiation markers, β-casein and whey acidic protein (WAP), which was very puzzling since we observed a near complete inhibition of β-casein in the differentiated state and activation of WAP in the undifferentiated state. In fact, MMTV downregulated the prolactin signaling pathway itself, and notably the prolactin receptor expression, regardless of the differentiation state of the cells. To delve deeper into MMTV\u27s impact on prolactin receptor expression, the three known prolactin receptor promoters were cloned upstream of the luciferase (Luc) gene and tested in HC11 and HC11 MMTV cells. These assays revealed a downregulation of Luc expression by the promoters in the presence of MMTV. Test of individual genes of MMTV identified the MMTV envelope (env) gene responsible for suppressing the prolactin receptor promoter, an inhibition that was reversed upon env deletion, confirming its role in this process. Given the global downregulation of gene expression induced by MMTV, we explored MMTV\u27s potential modulation of epigenetic marks in HC11 cells to repress gene expression. Interrogation of our mRNAseq data indicated a significant upregulation of the de novo DNA methyltransferase, DNMT3L, confirmed by RT-qPCR and western blot analysis. siRNA knockdown of DNMT3L restored prolactin receptor promoter activity, suggesting its involvement in MMTV-induced inhibition of global gene expression. Based on these observations, we speculate that downregulation of the prolactin pathway induced by MMTV in mammary epithelial cells is used by the virus to alter the protein composition of mice breast milk so that more of the cell resources can be used to make virus particles than β-casein; yet the whey content is kept constant to provide sufficient nutrition, ensuring efficient virus transmission to the pups without compromising their health. Interesting, a similar observation has been reported in another milk transmitted retrovirus, the bovine leukemia virus, which inhibits casein synthesis in mammary epithelial cells, irrespective of their bovine or mouse origin. Additionally, our data suggests that the extensive suppression of gene expression induced by MMTV Env via DNMT3L predisposes HC11 cells to cell transformation, broadening the current notion that insertional activation of cellular protooncogenes is the primary mechanism by which MMTV induces tumorigenesis, while supporting the role of env as a potential MMTV oncogene. Significance: Together, our study sheds new light into how a cancer-causing virus like MMTV manipulates host gene expression to its advantage by: 1) altering breast milk composition for enhanced viral transmission to the progeny, and at the same time 2) disrupting global molecular pathways responsible for epithelial cell growth and differentiation using epigenetic modifications like DNA methylation to potentially induce mammary cell transformation in mice. Considering the possibility that MMTV may be crossing the species barrier into humans, if proven true, our study can have direct implications for human breast cancer as well
Digital Overload, Coping Mechanisms, and Student Engagement: An Empirical Investigation Based on the S-O-R Framework
No full textAs avid users, university students find themselves immersed in the deluge of content being created and shared on digital platforms, which makes digital overload a significant concern. The present study examines the effects of digital overload on university students’ psychological well-being and how the use of coping mechanisms might help to mitigate some of these effects. The study developed a research model based on the S-O-R (stimulus, organism, response) framework and gathered data from undergraduate students at a major public university in the United Arab Emirates. To minimize the threat of common method bias, data collection was conducted in two rounds separated by two weeks. Hypotheses were tested using a partial least square path modeling approach. The findings show that digital overload causes psychological strains among students such as technostress and exhaustion, which subsequently encourage them to adopt coping mechanisms. The findings also show that the adoption of coping mechanisms is positively associated with student engagement. The study contributes to the literature by shifting the focus away from information overload—emphasizing digital overload instead—and investigating how students can respond to it by using coping mechanisms
The Impact of Using Gamified Augmented Reality in Developing Learning Engagement and Quality of Learning Life among Tenth-Grade Physics Students
Get PDFThe research aimed to examine the impact of gamified augmented reality (AR) on engagement in learning and the quality of educational life. The research sample included (90) tenth grade students distributed in three schools, and they were distributed into three groups of (30) students in each group, the first experimental group taught using gamified AR, the second experimental group taught using non- gamified AR, and the third is a control group taught in the usual way in the classroom, and each school included an independent group of research groups. A quasi-experimental design was adopted to study the impact of using motivational augmented reality on learning engagement and the quality of educational life. The researcher developed a learning engagement scale that included (24) statements distributed over (3) axes, namely: Behavioural Engagement, Cognitive Engagement, and Emotional Engagement. A quality of educational life scale was developed consisting of (36) statements distributed over (6) axes, namely: Autonomy, empowerment, personal development, positive relationships, meaningful life, and self-acceptance. The research experiment was applied for two consecutive weeks in the first semester of the academic year 2022/2023. The results showed the effectiveness of motivational AR in developing engagement in learning and quality of educational life compared to non- gamified AR as well as compared to regular classes.
Keywords: gamified AR, gamification, engagement in learning, quality of educational life, physics cours
تأثير رؤية 2030 في مسعى الرياض لتصبح مدينة ذكية: أولوية القوة الناعمة لاستراتيجية التحول الاجتماعي على القوة الصلبة للبنية التقنية المادية
Get PDFتناقش الورقة عملية تحول الرياض لمدينة ذكية. يروج في الأدبيات التي تتعاطى مع المدن الذكية التعامل معها كغاية في حد ذاتها وليست وسيلة لغاية. في هذه الحالة يكون التركيز على العناصر المادية للمدينة كالمباني الذكية والبنية التحتية لتكنولوجيا المعلومات والاتصالات (ICT) وتطوير إنترنت الأشياء (IoT). على النقيض من ذلك، تتعاطى هذه الدراسة مع المدينة الذكية باعتبارها وسيلة لغاية، بمعنى أنها أداة مساعدة لتحقيق التحول الاجتماعي والانتقال لاقتصاد المعرفة. فهي بهذا تعطي الأولوية للإنسان على العناصر المادية في المدينة. لهذا أهم شيء يتم التركيز عليه هو إعداد السياسات الاستراتيجية لإحداث هذا التحول الاجتماعي المنشود. بناء عليه قامت الرياض بتبني رؤية 2030 الاستراتيجية التي تضم العديد من البرامج والمبادرات لتحقيق هذه الأهداف. تقوم منهجية الدراسة على استخلاص البيانات الثانوية من المصادر الحكومية كالمواقع الرسمية والتقارير الدورية للهيئات والمنظمات ذات العلاقة والأوراق البحثية ذات الصلة. تشير نتائج الدراسة إلى أنه في حالة مدينة الرياض الذكية، فإن للدعم السياسي من أعلى سلطة وبالتالي السياسات الاستراتيجية التي صيغت لتحويل الرياض إلى مدينة ذكية هي التي كان لها الدور الحاسم والأولوية على حساب الجوانب المادية التي تم تطويرها بناء على توجيهات هذه السياسات. إن الإرادة السياسية القوية هي أساس نجاح تحويل الرياض لمدينة ذكية. فهذه الإرادة السياسية هي التي تولت صياغة الرؤية الإستراتيجية 2030 وما تضمنته من برامج ومبادرات، وساهمت بالتالي في ضخ زخم كبير لتحقيق التحول الاجتماعي المنشود وإنشاء مجتمع المعرفة حيث يتم تطوير وتنمية الرأسمال البشري الذي يشكل اللبنة الأساسية لعمال المعرفة knowledge workers في مدينة الرياض الذكية. أما البنية التحتية التكنولوجية المتطورة وإنترنت الأشياء المتقدمة والمباني الذكية ومعها كامل المكونات الستة للمدينة الذكية فهي محصلة تابعة لهذا المجتمع المعرفي الذكي Knowledge-based society ولهؤلاء العمال المهرة والمبدعين Creative workers
MOLECULAR GEOMETRY CHANGES IN SOME CARBONYLS AND AROMATIC RINGS UPON ELECTRONIC EXCITATION: HERZBERG-TELLER VIBRONIC COUPLING AND UNITARY DUSCHINSKY ROTATION
Get PDFThe common assumption in probing the dynamical motion of molecules is that the molecular electronic activity depends weakly on vibrational coordinates on electronic excitation. Therefore, electron-vibration interaction, which is known as Vibronic Coupling (VC), may be ignored. The Herzberg-Teller theory of Vibronic Coupling (HTVC) is a breakdown of the Born-Oppenheimer Approximation (BOA) since nuclear and electronic degrees of freedom can no longer be separated. The inclusion of a single quantum of a non-totally symmetric vibrational mode changes the overall symmetry of the state and permits the transition. Often, this assumption may be invalid, especially in carbonyl and aromatic compounds. This thesis will use both quantum mechanics and electronic structure theory of molecules to probe the breakdown of this assumption in carbonyls (formaldehyde H2CO, acetaldehyde CH3CHO, and acetone CH3COCH3) and aromatic carbonyl compounds (benzaldehyde C6H5CHO and benzophenone C6H5COC6H5). This work will investigate the extent to which HTVC is significant by looking at nuclear coordinates deformation and electronic density redistribution upon electronic excitation. Non-totally symmetric vibrations are important to identify the coupled electronic states whereby intensity is borrowed from nearby electronic states in case of forbidden electronic transitions by symmetry in the FC region. This electronic density redistribution distortion may be due to the Duschinsky Matrix (DM) and HTVC interaction renders information on how the transition moment varies as the molecular geometry changes, giving rise to the non-Condon regime. This coupling should be probed to see if it is caused by orbital interaction and this interaction would give rise to non-adiabatic coupling. This molecular geometry alteration is so important for probing and hence understanding vibration-electron coupling in polyatomic molecules
The Perceptions of Teachers of Students with Autism Regarding Using Applied Behavior Analysis (ABA) to Improve Social Skills in Saudi Arabia
Get PDFAims: The purpose of this study was to investigate the perceptions and experiences of teachers of autistic students in Riyadh and Jeddah regarding the use of applied behavior analysis (ABA) to improve social skills. Methodology: I used a qualitative method to analyze phenomena under inquiry from three different data points: surveys (n=51), interviews (n=6), and phenomenologically (n=2). Results: The findings indicated that some of the main factors affecting how teachers view and utilize evidence-based practice (EBP) in their scope of practice are refresher training, skills, knowledge, peer support, and institutional policies. Discussion and conclusion were discussed.
Keywords: Special education, Saudi Arabia, Social skills, Autistic, Autis
Can Vocabulary and Grammar Hold the Doorway for College Reading Success? The Case of Arabic Learners of English
Get PDFReading is an important skill for college success. This study investigated cognitive predictors of English reading comprehension success among college students whose first language is Arabic. Knowledge of vocabulary/grammar emerged as the strongest predictor of reading success, followed by silent reading fluency, and then decoding skill. However, metacognitive awareness of reading strategies did not statistically significantly contribute to the model. Findings suggest that Arabic speakers draw on their vocabulary and grammar knowledge when tackling an English reading comprehension task, skills that are language specific to L2. Implications include the recommendation for placing the development of college students’ language reservoir at the heart of language programs, and incorporating silent reading fluency and decoding skill within these programs. The finding regarding metacognitive awareness of reading strategies brings into question whether a certain level of language proficiency must be met by language learners before reading strategies begin to contribute to reading comprehension achievement.
Keywords: Arabic speakers, Cognitive Model, college reading, decoding skill, EFL, ELL, English language learners, ESL, grammar knowledge, metacognitive awareness of reading strategies, reading comprehension, second and foreign language acquisition, silent reading fluency, vocabulary knowledg