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Hybrid Liposome/Metal–Organic Framework as a Promising Dual-Responsive Nanocarriers for Anticancer Drug Delivery
No full textIn this work, liposome-coated iron (III) benzene-1,3,5-tricarboxylate (Fe-BTC) metal–organic framework is examined as a promising pH/Ultrasound dual-responsive nanocarriers for doxorubicin (DOX) delivery. The successful coating of the MOF particles (Lip-Fe-BTC) with the phospholipid bilayer (PBL) was established by direct fusion into the synthesized liposomes. The liposome coating was verified using several techniques, including dynamic light scattering (DLS) and transmission electron microscopy (TEM). The DLS measurements showed an increase in the average particle diameter of liposomes from 150 nm to 163.1 nm for Lip-Fe-BTC particles. The Fe-BTC particles had the highest average particle diameter (287.3 nm). These results demonstrated that the PBL reduced the aggregation of the particles and improved their dispersity in the release medium. The TGA results demonstrated the MOF’s excellent thermal stability. Furthermore, the nanocarrier’s loading efficiency and capacity were determined to be ~90% and ~13.5 wt.%, respectively. The in-vitro DOX release experiments demonstrated that the DOX-loaded Fe-BTC and liposome-coated Fe-BTC particles showed good pH and US dual-responsive capability, making them promising nanocarriers for drug delivery. The application of US enhanced DOX release from both Fe-BTC and liposome-coated Fe-BTC. In the case of Fe-BTC-DOX particles, the application of US enhanced the DOX release to around 38% and 67%, at pH levels of 7.4 and 5.3, respectively. Similarly, DOX release from the Lip-Fe-BTC-DOX particles reached ~35% and ~53%, at pH levels of 7.4 and 5.3, respectively. The MTT assay showed the biocompatibility and low cytotoxicity of these nanocarriers below 100 µg/ml.American University of Sharja
Microwave Triggered Release of Doxorubicin from Metal-organic Frameworks
No full textA Master of Science thesis in Biomedical Engineering by Syeda Fiza Fatima entitled, “Microwave Triggered Release of Doxorubicin from Metal-organic Frameworks”, submitted in November 2022. Thesis advisor is Dr. Rana Sabouni. Soft copy is available (Thesis, Completion Certificate, Approval Signatures, and AUS Archives Consent Form).Metal-Organic Frameworks (MOFs) are ideal candidates for a variety of applications based on their remarkable properties such as high surface area and porosity. A substantial number of studies have been conducted to examine the synthesis techniques of MOFs as well as their implementation in drug delivery, biosensing, adsorption, separation, etc. An extensive overview of the recent work performed to explore the structure, properties, and applications of MOFs was reviewed, in order to establish a strong foundation for this research. In recent times, stimuli responsive MOFs have been fabricated and investigated for their utilization in targeted drug delivery applications with the help of Ultrasound, Light and heat. We proposed the utilization of Microwaves (MW) for stimulus responsive in-vitro release of Doxorubicin (DOX) from MOFs named Fe-BTC and MIL-53(Al) for the purpose of drug delivery in cancer therapy. DOX was encapsulated into Fe-BTC and MIL-53(Al) overnight and the drug loading capacity was measured to be as high as 67% for Fe-BTC and 20-40% for MIL-53(Al). Several characterization tests were performed to confirm and explain the drug loading and releases mechanism from both MOF’s samples, including XRD, FTIR, TGA, BET, FE-SEM and EDX. Fe-BTC exhibited drug release efficiency of 54% after 50 minutes as a result of Microwave at 7.4 pH whereas 11% was achieved without Microwave. Similar observation was obtained at pH 5.3, however the release efficiencies in both cases were higher with Microwave (40%) compared to without (6%). MIL-53(Al) was observed to be more pH sensitive as it showed higher release (66%) after 38 minutes in pH 5.3as compared to 55% after 50 minutes at pH 7.4 with the application of Microwave irradiation. The experimental results revealed that both MOFs were highly heat responsive. Moreover, results of MTT assay revealed that the cells remained viable at different concentrations of the MOFs after two days of incubation verifying their biocompatibility which demonstrates that MOFs could be good candidates for tumour targeting. Additionally, the cells remained viable at different exposure lengths confirming that Microwave is a safe modality to use for triggering release of a drug from MOFs.College of EngineeringMultidisciplinary ProgramsMaster of Science in Biomedical Engineering (MSBME
Modeling of the In Vitro Release Kinetics of Sonosensitive Targeted Liposomes
No full textTargeted liposomes triggered by ultrasound are a promising drug delivery system as they potentially improve the clinical outcomes of chemotherapy while reducing associated side effects. In this work, a comprehensive model fitting was performed for a large dataset of liposomal release profiles with seven targeting moieties (albumin, cRGD, estrone, hyaluronic acid, Herceptin, lactobionic acid, and transferrin) in addition to the control liposomes under ultrasound release protocols. Two levels of ultrasound frequencies were tested: low frequency (20 kHz) at 6.2, 9, and 10 mW/cm2 as well as high frequencies (1.07 MHz and 3 MHz) at 10.5 and 173 W/cm2. At a low frequency, Hixson–Crowell, Korsmeyer–Peppas, Gompertz, Weibull, and Lu–Hagen showed good fits to our release profiles at all three power densities. At high frequencies, the former three models reflected the best fit. These models will aid in predicting drug release profiles for future in vitro studies.Dana Gas Endowed Chair for Chemical EngineeringAmerican University of SharjahSheikh Hamdan Award for Medical SciencesFriends of Cancer Patient
Unified Blockchain Platform or Carbon Emission Trading: A Comprehensive Smart Contracts System Integrated With The Internet Of Things Technology
No full textA Doctor of Philosophy Dissertation in Engineering Systems Management by Alia Al Sadawi entitled, “Unified Blockchain Platform or Carbon Emission Trading: A Comprehensive Smart Contracts System Integrated with The Internet Of Things Technology”, submitted in May 2022. Dissertation advisor is Dr. Malick Ndiaye. Soft copy is available (Thesis, Completion Certificate, Approval Signatures, and AUS Archives Consent Form).College of EngineeringDepartment of Industrial EngineeringPhD in Engineering - Engineering Systems Management (PhD-ESM
A Decision Support Tool for Smart Campus Applications – An AUS Case Study
No full textA Master of Science thesis in Engineering Systems Management by Mohamed Faisal Khatri entitled, “A Decision Support Tool for Smart Campus Applications – An AUS Case Study”, submitted in December 2022. Thesis advisor is Dr. Vian Shawket Ahmed. Soft copy is available (Thesis, Completion Certificate, Approval Signatures, and AUS Archives Consent Form).Since the last decade, advancement in the sciences around the world is causing an unstoppable incline towards smart technologies across multiple industries. Smart technologies come with numerous benefits ranging from reduced energy costs to productivity gains to lastly but very importantly, sustainability. One application of these smart technologies that attracts the objective of this thesis is “Smart campuses” which is basically the application of smart technologies to an educational institution. Few research provides the framework of the different available smart technologies that can be applied to a smart campus such as smart classrooms, smart transportation systems, smart operations and many more. However, applying all the available technologies at any campus would not be feasible in many institutes due to the various restrictions imposed by environment, culture and lack of funds, equipment, etc. Hence, this thesis involves development of a mathematical decision-making tool based on the Evidential Reasoning Approach for a successful implementation of smart applications to a university campus. The aim of this tool is to provide decision makers with rankings and utilities that enables them to decide on which smart applications (alternatives) are needed in the university based on certain inputs (attribute weights and beliefs at each evaluation grade). Upon building this tool, it was validated against 50 Truth data points from experts to analyze the quality of the tool. It was found that there is no statistically significant difference between the expert provided recommendations and the ones provided by the tool, even at a 0.05 significance level along with the area under ROC curve to be 0.734, depicting the tool performs as per expectations. Moreover, the tool’s performance evaluated using several metrics like accuracy, sensitivity etc. was upwards of 90% therefore further supporting the reliability of the tool. Lastly, the tool developed in this thesis is a generalized tool and hence can be used around the world with different number of alternatives and attributes by filling in the required inputs to the tool.College of EngineeringDepartment of Industrial EngineeringMaster of Science in Engineering Systems Management (MSESM
HEVC Video Encryption with High Capacity Message Embedding by Altering Picture Reference Indices and Motion Vectors
No full textA high capacity message embedding in encrypted HEVC video is proposed in this paper. The challenges addressed in this paper include keeping the encrypted video compliant with standardized decoders, correctly decrypting the video and finally, correctly extracting the message bits. The message embedding is achieved by altering the values of reference picture indices and motion vectors which results in scrambled video. Sixteen picture references are used in this work and therefore, combined with alteration of motion vectors, a maximum of six message bits can be embedded per coding unit. Motion vectors are altered by swapping their x and y components and/or changing their signs. This is achieved with full compliance with the HEVC video syntax. To extract message bits, an authorized decoder builds a classification model per video sequence and uses it for predicting the true values of the reference indices and motion vectors. As such, message bits are extracted and the video is correctly reconstructed to its unscrambled state. Coding units that result in misclassification are identified at the encoder and excluded from message embedding. This results in slightly lower embedding rates but ensures accurate video reconstruction. Using nine video sequences of various resolutions that are compressed using four different quantization parameters, the experimental results revealed that the true average message embedding rate is 2.7 bits per coding unit or 173 kbit/s. This is achieved with accurate video reconstruction at the expense of increasing the bitrate of the encoder by 3%. Comparison with existing work shows that the proposed solution is superior in terms of embedding capacity whilst reducing the excessive bitrate of the encoder
Simulation of the Dynamic Effects of Wave Slamming on Flexible Marine Structures
No full textA Master of Science thesis in Civil Engineering by Mutaman Tarig Mohamed Elyas entitled, “Simulation of the Dynamic Effects of Wave Slamming on Flexible Marine Structures”, submitted in December 2022. Thesis advisor is Dr. Mohammad AlHamaydeh. Soft copy is available (Thesis, Completion Certificate, Approval Signatures, and AUS Archives Consent Form).Flexible marine structures such as open piled jetties, which are comprised of a deck supported on piles, are commonly used in coastal areas around the world. Due to certain conditions, these structures are sometimes exposed to direct wave attack, in which the deck is exposed to vertical slamming load, possibly causing extensive local and global damage. Wave slamming is a complex phenomenon influenced by several parameters making it difficult to predict or quantify. Effects of wave slamming on flexible marine structures were investigated in three stages. Stage I included a review of a 3D physical modelling study conducted by a specialized company to investigate wave loading on a piled jetty structure located on the coastline of Dubai, UAE. Stage Ⅱ included a wave load prediction based on parametric equations. Stage Ⅲ included computational fluid dynamics (CFD) numerical modelling of the same jetty structure from StageⅠandⅡusing DualSPHysics software, which is based on smoothed particle hydrodynamics (SPH). Stage Ⅲ was divided into three phases. Phase 1 comprised of calibrating the CFD model against the physical modelling study by replicating the physical model setup and wave conditions in DualSPHysics. Phase 2 comprised of a sensitivity analysis for the inter-particle distance parameter in DualSPHysics, which represents the numerical model’s resolution and determines the required computational and storage demands of each simulation. Five inter-particle distances were investigated in Phase 2 with 0.005m selected as the suitable inter-particle distance to be used in Phase 3. Phase 3 comprised of simulating three relative wave parameters: (a) Relative Clearance (Δh /Hs), (b) Relative Wave Height (Hs / h), and (c) Relative Deck Width (B / λ). For each relative wave parameter, five different values were simulated to investigate their effect on the wave pressure imposed on the jetty. A control simulation was initially developed, which was then used as the base case for all the subsequent simulations. Wave pressure distributions were plotted for each simulation and the maximum pressures were compared to determine the trends caused by the varying parameters. Finally, results from the three stages were compared and recommendations were provided on the suitability of each method for the design of flexible marine structures.College of EngineeringDepartment of Civil EngineeringMaster of Science in Civil Engineering (MSCE
Decarbonizing the ceramics industry: A systematic and critical review of policy options, developments and sociotechnical systems
No full textCeramics are considered one of the greatest and earliest most useful successes of humankind. However, ceramics can be highly damaging to natural and social systems during their lifecycle, from material extraction to waste handling. For example, each year in the EU, the manufacture of ceramics (e.g., refractories, wall and floor tiles and bricks and roof tile) emit 19 Mt CO2, while globally, bricks manufacturing is responsible for 2.7% of carbon emissions annually. This critical and systematic review seeks to identify alternatives to mitigate the climate effects of ceramics products and processes to make their lifecycle more sustainable. This article reviews 324 studies to answer the following questions: what are the main determinants of energy and carbon emissions emerging from the ceramics industry? What benefits will this industry amass from adopting more low-carbon processes in manufacturing their products, and what barriers will need to be tackled? We employ a sociotechnical approach to answer these questions, identify barriers to decarbonise the ceramics industry, and present promising avenues for future research. In doing so, we show that environmental and energy challenges associated with the ceramics industry are not just limited to the manufacturing stage but also relate to the extraction of raw materials, waste disposal, and landfilling.UK Industrial Decarbonisation Research and Innovation Centre (IDRIC)The Bryden Centre projectEuropean Union's INTERREG VA Programm
Fluid properties impact on energy separation in Ranque–Hilsch vortex tube
No full textThis paper examines the energy separation in vortex tubes which is a passive device that can split a pressurized room temperature gas stream to hot and cold streams. The paper employs numerical simulations to investigate the impact of various working fluids such as helium, air, oxygen, nitrogen, and carbon dioxide on the energy separation in the vortex tube, using the SST k− turbulence model with viscous heating. A three-dimensional numerical investigation is sued to examine the effect of a single fluid property on vortex tube performance, while keeping the rest of the fluid properties unchanged, which is impossible to achieve via experimental study. The numerical investigation examines the influence of molecular weight, heat capacity, thermal conductivity, and dynamic viscosity on energy separation. The results show that energy separation performance improves with lower molecular weight and heat capacity, and higher dynamic viscosity of the working fluids, while no impact of the thermal conductivity is observed. Out of five gases tested in this study, helium has yielded the maximum temperature separation, while carbon dioxide has yielded the lowest performance. Results show that viscous dissipation contributes to the temperature separation in vortex tube